Atlas of Orthodontics Principles and Cinical Applications ppt

ella Dental Development The development of teeth begins in utero, but it is not until 2 to 3 years of age that all deciduous teeth appear in the toddler's mouth,I.2 The most common seq

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Atlas of

• Principles and

ical Applications

Baylor College of Dentistry Dallas, Texas

Principles and

ical Applications

A DiI 'isioti if

Ifarra1m Broce & Com pan y

P h i lade lp hia london T oronto

M o nt rea l Syd n ey T o k yo

Preface

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Atlas of Orthodontics: Principles and Clinical Applications was written with the

intention to introduce to the world of clinical orthodontics its first illustrated text

This colorful methodological presentation of the most up-t<rdate infonnation and

direct clinical application aims to aid the students of orthodontics in understanding

the logical sequence from diagnosis to a successful treatment In addition as the

innovations and revolutionary improvements in clinical orthodontics over recent

years have widened the scope of diagnosis and broadened the horizons of treatment

this work aims to serve as the most updated illustrated reference of all these new

advances Thus, the atlas can very easily serve as a guide to students, dentists and

orthodontists alike

Al Ias of Orthod o ntic s is an array of original photographs and drawings that high

-light the state.of-the-art modern practice of orthodontics with fresh, new ideas on

diagnosis, treatment planning, and, above all, therapy and its clinical application It

provides the reader with a step-by-step decision-making approach to the practice of

orthodontics The comprehensive yet easily readable text and the legends that accom

-pany the illustrations span the breadth of the references The clinician learns various

techniques from photographic material (in color) directly from the patient's mouth

This atlas offers a system that gives the best results while disclosing invaluable tips on

preventing clinical blunders that would lead to complications It methodically explains

the reasons for all the clinical techniques used based on fundamental biological and

biomechanical principles, so that the reader will easily understand the orthodontic

thinking process Furthermore, it will give the practitioner the satisfaction of being

able to apply clinically all that he reads While reflecting the most current accepted

treatment methods, its structured outline and continuity provide all the information

in an easy, commonsense formal No other book in the field of orthodontics focuses

on the clinical side of day-to-day practice with such an abundance of illustrations that

educate the reader on critical judgment and clinical modalities that give the best

treatment results It is an invaluable educational source of the art and science of

clinical orthodontics for the graduate and undergraduate student, for the general

dentist, and even for the most experienced orthodontist

My sincere appreciation is addressed to the following individuals for their signifi

-cant contributions to my education and academic endeavors in orthodontics: from

Baylor College of Dentistry, Drs Richard Cecn, Robert Gaylord, Tom Matthews, and

Peter Buschang, Rohit Sachdeva, Doug Crosby, Monte Collins, Joe Jacobs, Richard

Aubrey, Moody Alexander, Wick Alexander, Ed Genecov, Larry Wolford, Mr Stan

Richardson, and Mr Chris Semos; from the University of Minnesota, Drs William

Liljemark, Richard Bevis, Gerald Cavanaugh, T Michael Speidel, Kevin Denis, Mark

Holmberg, James Swift, Robert Feigal, Robert Gorlin, William Douglas, and the

former President of the American Board of Orthodontics, Lloyd Pearson; from the

University of Maryland, Dr Dianne Rekow; from Tufts University, Drs Nicholas

Darzenta and Anthi Tsamtsouris; from the University of North Carolina, Dr William

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Proffit; from the University of Southern California Dr Peter Sinclair; from the University of Iowa Drs John Casko and Samir Bishara; from the University of Athens, Drs Meropi Spyropoulos, Paul Apostolopoulos, and George Vouyouklakis; from the Medical College of Virginia, Dr Robert Isaacson; and from Louisiana State University, Dr Jack Sheridan; and from the University of Toronto, Dr Angelo

Metaxas

A special acknowledgment is addressed to one man who is an inspiration to many

in the field of orthodontics: Dr T.M Graber, Editor-in-Chief of the American J ournal

of Orthodonti cs 0 11(1 D enlofadal Orthopedics I am deeply grateful to him for his advice, recommendations, endless energy and enthusiasm, and the wonderful support

that all my academic endeavors have enjoyed from him

I am also grateful to all the students with whom I have had the distinct pleasure of working, from the undergraduate junior dental class at the University of Minnesota that presentcd me with the greatest honor of my academic life, the "Teacher of the Year Award" after my very first year in teaching, to the graduate students at the same

school and at Baylor College of Dentistry for their excellent work on all the cases that

we treated together Their critical thinking and quest for knowledge have certainly influenced me and the way I teach

ANTttONY D VIAZIS , DDS, MS

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Contents

Part A Preliminary Examination of the Patient

C hapter 7 Oral H ygien e Consi d crd ti o n s 29

C hapter 8 Period on tal Pl as ti c Surgery 35

Part B Facial and Cephalometric Evaluation

C hapter 2 Bolt o n and Mi c higan Standa rds 4 5

C hapter 5 Ant e ro posterior Skeletal A ssess m en t 59

C hapter 7 Cep halometric Dental Evaluati on 73

Part C Growth

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Chapter 2 Growth Superimposition / Eva luation 89

Cha pter J Biom ec hani cs of T oo th M oveme nt 105

C hapter 1 Orthodont ic M e t a l Fixed Appliances 1 17

C hapter 4 Direct Bonding o f Bm c kets / Adhesive 1 29

Appliances

C hapter 7 Thumb-Su c kin g a nd Hab it Co nt rol 235

CO n/enls • xi

Pari F Orthodontic Treatment Modalities

C hapter 2 Tooth Gui da nce (Serial Ex tra c ti on) 261

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C hapter $ T reatmen t Planning in th c Permancnt· 271

Dentition

C hapter 5 In c i so r EX lnl c tion / Mi ssing In cisor / 307

Second Molar Ex tra c ti o n Th cnl P Y

C hapter 6 Intru s ion M echa n ics / Co mprom ised 323

Period o ntium Thcmp y

C" e r

Chief Complaint

The examination or the patient in the office should always stan with the medical history, as is

done in any dental offiCC I

- 3 The dental clinical evaluation should follow, where

general notes, as well as an evaluation of the intraoral soft tissue, teeth, and oral function, and panoramic radiograph are made.2

•1 Any operative, periodontaL and

endodontic work (if needed) should be completed before initiation of onhodontic

treatment, whereas any tcmporomandibular joint (TMJ ) pain or dysfunction should

be addressed before the onset of onhodontic treatment (Table A 1.1) Permanent

prosthetic work should be done afterward

Inquiring about the patient's chief complaint, i e the reason he or she seeks orthodontic treatment, is of utmost importance The chief complaint must have been

met by the end of treatment, otherwise the patient will not be happy, even if the

orthodontic therapy is of the highest standards If the patient or guardian has unrealis

-tic expectations that may not be met with treatment, the clinician ought to educate

him or her so that he or she understands the limitations of the various therapeutic

modalities in modern orthodontics A good example is the change of the soft tissue (lips) as a result of extraction therapy A patient will not be satisficd if after 2 years of orthodontics, he or she has a beautiful occlusion accompanied by late nasal growth

that makes the lips appear more retrusive.· In addition, the low degree of predictabili y associated with the upper lip in rcsponse to orthodontic tooth movemcnt, possibly

caused by the complex anatomy or dynamics of the upper lip, I might cause able changes in the soft-tissue profile in crowded cases that involvc extractions of

undesir-permanent teeth Nononhodontic measures (i e rhinoplasty or genioplasty) should be

discussed with the patient before the stan of the orthodontic treatment I

4 • Pan A Pr eliminary EXa m i nOl ian of/ h e Par ie ni

Table 1 1 Cl ini cu l Information Form (DenIal)

General Information Parent n a m e Guardian na m e

P a ti ent h ei gh t Father' s height Mo ther 's h e i ght • P at ie nt mot iv ation

F a mil y hi s to ry o f ma loc clusion

Intraoral Soft -Tissue Evaluation

Pa th o logy Oral hygiene Atta ched gingiv a G ingi v al re ce ssi o n

Intraoral DenIal Evaluation and Panoramic Radiograph

U y poc;a lcilicat ion F ract ured CW" i11 Crownjbridgc

F • ne" IOna I Eval • ation Spee ch pathology Musc le tenderness I nt e rnal d e rnng e ment

Br e athing C l en ching Stage I (early or late clicking)

T o n g u e s i z e Deviation upon opening Stage III (acute lock) lip ton i ci t y Deviation upon closing S tag e IV ( f un ct io n o ff d is k)

T o n si l size R ange of motion ( R O M ) S tage V ( pain , grating sound )

References

I Talass MF, Tallas L, and Baker RC: Soft tissue pro file changes result i n g f rom re tract io n of max il la ry inc i so rs Am J Onhod Dc:qtofacial Onho p 9 1 : 38 5-394 , t98 7

2 Proffit WR , and White RP, J r : Surg i cal · Orthod o ntic Treatment St Lou is MO : Mosby Y ea r Book 199 1

3 Proffit WR: Co ntem{IQraryOrrhodolUi c J SI Louis, M O : C V M os b y Co 1 86

4 Busc hang PH , Via z is AD , DelaCruz R , a nd Oakes C : H ori zo ntal gr o wth o f the soft·ti ss ue nose re l at i v e

to maxillary growt h Jain Orthod 26 : 111 - 11 8, 1 992

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Dental Development

The development of teeth begins in utero, but it is not until 2 to 3 years of age that all

deciduous teeth appear in the toddler's mouth,I.2 The most common sequence of

eruption starts with the lower central incisors, followed by the upper centrals in the first 6 months of life; the upper lateral and lower incisors crupt by the end of the first year of age; the upper and lower first deciduous molars, followed by the cuspids, appear by 18 months, and the lower and upper second deciduous molars erupt by the

cnd of the second year or as late as the third year of life 1 ): (see Fig FI.l S) Past this point, very little increase in dental arch width occurs Spacing is desirable in the primary dentition; lack of spacing means large teeth or small arches and is strongly

suggestive of crowding in the permanent dentition

The eruption of the permanent dentition starts around the age of 5 or 6 years with

the first permanent molars distal to the second deciduous molar tceth.l.2 The periods 5

to 8 years of age and 9 to 12 years of age are called early and late mixed dentition

stages, respectively Around 6.5 years of age, the lower central incisors erupl, followed

by the upper centrals by 7 years of age 1 ,2 The lower laterals erupt by age 7.5 years, followed by their maxillary counterparts at age 8 years or as late as 9 years of age l.l (see Fig F1.I6) At approximately 10 years of age, the lower permanent cuspids make

their appearance in the child's mouth, followed by the upper first bicuspids at age 10.5 years and the lower first bicuspids at age II years.1,2 The upper and lower second bicuspids erupt very close to each other at age 11 5 years, followed by maxillary

cuspids and the second permanent molars by the age of 12 years or as late as age 13 years.l,2 One must keep in mind that there is one significant variation of tooth

eruption in the population: teeth may erupt as early or as late as 2 years in relation to the average ages mentioned above and still be considered normaL

Teeth usually erupt when the roots arc one half to three quarters formed.2 After the end of the early mixed dentition stage, the upper incisors may have substantial spacing

as their crowns are inclined toward the distal This is called the "ugly ducking stage" and is considered a nonnal condition that will sclf-correct later on; it happens due to

the eruption path of the permanent cuspids as they come into position for eruption along the roots of the lateral incisors (Fig A2 1)

The sum of the mesiodistal width of the deciduous cuspid and molar teeth is 1.3 and 3.1 mm greater than the permanent cuspid and bicuspid tccth in the maxilla and the mandible, respectively (leeway space).2 This space is generally used in the perma ~

nent dentition to permit improvement of possible crowding of anterior teeth and also

to allow a slight mesial migration of the first permanent mandibular molar into a solid class I occlusion.2.) The leeway space may be quickly lost from premature exfoliation

of teeth and quick mesial movement of the permanent molar to an extent that the

lower second bicuspid may be blocked out toward the linguaJ2 (see Fig 06.7) It

should be noted that the last increase in dental arch width occurs as the permanent

cuspid teeth erupt into their position in the arch Expansion of the arches in this area

is questionable past this stage

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6 • ParI A Preliminar y t.:ramillation of/ h e Paticrll

A2 1

F ig ur e A2 1 The " ugly du ckling" stage of tooth development

In a study on the changes in the molar relation between the deciduous and

perma-nent dentitions, it was concluded that 6 1.6%, 34.3%, and 4 I % of patients end up with

a class I, class II, and class III permanent molar relationship, respectively.] Patients

who start with a full distal step in the deciduous dentition develop into a class II molar relationship; thus, treatment should be initiated in these cases as early as possible Conversely, almost half (50%) of patients who have a 50% class II primary

molar relation (end-to-cnd flush plane) develop a class I pe:nnanent molar occlusion,)

Close observation of these patients is nceded until a class I relation occurs,

References

I M oh l NO , Zarb GA C arl sso n GE , a nd Ru gh JO : A Textbook of Occlusiol! Ch ica go: Quintessence

Publi s hing 1988

2 Unde rgraduat e syllabu s Uni vers it y of M innesota, Depanm e n t of O n hod o n t cs Minnea pol i s, M N 1 989

3 Bi s hura SE, Hoppen s BJ , Ja cobse n J R and K o hout Fl C hang es in the molar rela t ions h i p between the

d ec idu o u s and pennan e nt d enti ti on: A longi tudinal s tudy Am J Onhod Dentoracial Onh op 93:19 - 28

1 988

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Articulated Casts

The most supero-anlcrior position of the condyle is musculoskclctally the most stable position

of the joint (centric relation),I-l In this position, the condyles arc resting against the posterior slopes of the articular eminences with the articular disks properly interposed and all of the muscles that coordinate joint movement at rest I

- 1 During rest and function, this position is both anatomically and physiologically sound A posterior force 10 the mandible can displace the condyle 10 an unstable posterior (or retruded) position Because the rctrodiscal tissues arc highly vascularized, well supplied with sensory nerve fibers, and not structured to accept forces, there is great potential for eliciting pain or causing breakdown,l.3

The position of the mandible where the relation of opposing teeth provides for maximum occlusal intercuspation is called centric ocdusion.I-4 This, ideally, should coincide with centric relation4

; this is what the clinician should strive for during orthodontic treatment In most cases, a slight discrepancy of about I mm also can be acceptable, where the position of the mandible in centric relation is slightly behind its position in centric occlusion

In contrast to craniometric variables, which have high heritabilities, almost all of the occlusal variability is acquired rather than inherited.5 Thus, a careful examination

of the patient's malocclusion is essential This is best done from a set of articulated casts in centric relation (CR) (Fig A3 I)

The following wax bite registration technique is suggested for proper recording of the patient's bitc': the right thumb is placed on top of the patient's chin with the right index finger under the patient's left gonial angle and the right second fmger under the patient's right gonial angle (Fig A3.2) The mandible is allowed to close (Fig A3.3) in such a manner that the lower incisors contact the anterior wax until a 2-mm posterior opening in the molar area is obtained (Fig A3.4) When the patjent squeezes the

muscle contractions scat thc condyles in a superior and slightly anterior position against the eminence.' The objective is to gain an index of both maxillary and mandibular incisal edges without making any tooth contacts The anterior wax is cooled down and removed while a soft posterior wax is placed against the maxillary posterior teeth (first molar and second premolar area) (Fig A3.5) The hard anterior wax is secured in the anterior region (Fig A3.6) and the mandible is gently manipu-lated into centric relation as described atxlVc (Fig A3.7) After the mandibular closurc

has been stopped by the limit of the indexes in the anterior section (Fig A3.8), both picces of wax are removed aftcr they are cooled down with air-spray (Fig A3.9) A

centric occlusion wax bite is also taken as the patient opens widely and bites all the way through the wax until the teeth touch fully

8 • rart A PT("iminary E x aminati Q n of rile Patient

A 3 1

Figure "'3 1 Arti c ulated casts on SA M 2 (Great Lak es , NY)

a rticulat or Onl y b y mounting th e casts are w e a bl e t o

notice any prematurities , fu n c ti ona l s hi fts, and th e exact

relationship o f t ee th i n ce ntri c re l ation H and-articu l ating

polished cas ts ca nnot capture init ial tooth c o nt acts

A3 3

Figure A3 3 The patient' s mandible i s allow ed to close ge ntl y

A3 2

F"tgUre A3 2 H and ma n ipulati o n for record ing ce ntri c re l a

-tion (C R ) pos iti o n: th e clinician's right thumb is placed on

t o p o f the patient's c hin , th e right in dex finger under th e

pati ent's l e ft go n ia l angle , and th e righ t seco nd fin ge r un d e r

the patient's righ t gonial angle

A3 4 Figure "'3.4 The closing moti o n is stopped when the lo wer

in c i so rs come in contact with th e ant erior w ax Note th e bile opening in the bicuspid / m olar area No pos t erio r teeth are allowed to co ntact

A3.5

Flgur A3 5 A soft po s t e ri o r piece of wax i s pr esse d lightly

against the posterior teeth

rtgure Al 7 The mandibl e i s again very gently manipulated

into C R Note that th e anterior wax is held against the

upper a nt e rior teeth during the closing motion o f th e

Figure A3.8 Th e mandibular closing m otio n is s topped as soo n as the low er anterior t ee th come in co nta c t with the

h a rd anterior wax The posterior teeth made their c u s p

i ndent a tion s in the posterior wax , with o ut eve n coming in

co ntact with th e ir co unt e rparts Th is wa y, th e mu sc l es ha ve

gu ided a nd seated t he co nd yles i n th e m os t s upero-anteri or pos it ion again s t th e em in e n ce

10 • Pllrt A Preliminary Examination o/llw Patient

A3 9 Figure A3.9 The wax pieces are cooled down with air-spray before they are removed from the mouth

Once mountcd on the articulator, the dental casts are used to evaluate the following7

Overbite

The vertical overlap of teeth is the overbite (08) The 08 in the incisor area should

be approximately 2 mm (see Fig CI.I8)

Overjet

The horizontal overlap of teeth is the overjet (OJ) The OJ in the incisor area should

be 1 to 2 mm (see Fig C I.I8)

Crowding

The best and most accurate way to evaluate the existing arch length discrepancy is by measuring the width of all the teeth in the arch with a campus, as well as measuring the actual arch length.' A clinical way to assess crowding is by "eyeballing" it, taking into consideration the average width of various major teeth (bicuspids- 7 mm; cuspids- 8 mm; lower incisors- 6 mm; upper centrals - IO mm) By subtracting how much tooth material is blocked out of the arch or is in a crowded position, one

may very quickly evaluale the space that is needed to obtain good tooth alignment

This is undoubtedly a very crude method, but one that clinical experience has shown

to approximate (+ 1 mm) to the exact discrepancy (sec Figs 06.6, D6.7, D9.18,

09.19, F4.62 F4.63, F5.3, F5.4 F5.11, F5.12, F5.24, F5.25) The cause of crowding

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C'Iulpltr J A f//CII /OIN Costs • 11

may differ from one subject to another or there may be morc than one factor

contributing to the development of crowding in any onc individual B

Crossbite

Crossbilc occurs when one or morc teeth arc in an abnonnal buccolingual relship.? Single-tooth crossbitcs arc usually dental in nature (see Figs E4.1, E4.2)

ation-Multiple-tooth crossbitcs are anterior (sec Fig C1.I3) or posterior (sec Figs e 1.1 3

C1.26, C1.30) and usually skeletal in nature.? Anterior looth crossbites may be

"pseudo class III" (due to a shift) (see Figs F1.I6, F1.I 7) or "true class III" (true

skeletal) (see Fig C1.13),7 Posterior crossbitcs arc unilateral or bilateraL Unilateral, multiple-tooth crossbites arc usually the result of a side shift to one side from a

bilateral skeletal crossbite The vast majority of multiple-tooth crossbites are bilateral and are due to a constricted maxilla (see Fig F4.I05) Multiple-tooth crossbiles

should be corrected as soon as possible (the youngest known patient is 3 years old) to avoid the possible development of a skeletal malocclusion or abnormal eruption of

teeth, as well as to improve the patient's esthetics9 (sec Figs F1.l2 through FI.1 5)

Dental Midlines

The facial midline (see Fig B l.l ) (middle of eyebrows, tip of the nose, cupid's bow)

should coincide with the upper dental midline (between the upper centrals) and the

lower dental midline (between the lower centrals) (sec Fig 09.27) If a compromise must be made due to the patient's malocclusion, it may be best to leave the lower

midline off by I to 2 mm (a lot of patients do not show their lower tccth upon smiling) The upper denial midline should coincide with the facial midline for an esthetically pleasing smile (see Fig A8.3)

Tooth-Size Discrepancy

A3.10

A tooth-size discrepancy (TSO) exists when the size of the lower or the upper tccth is

not in proportion with that of their counterpans.IO- 12 An anomaly in the size of the upper lateral incisors is the most common cause, but variations in bicuspids or other tccth may be prescnt7 (see Figs A3.1O, F3.7, F5.22) In such a case, it would be impossible to obtain an ideal OB/OJ relation of 2 mm when the cuspids are in a class

FIgU r e A,3 10 Small upper left l atera l Spa ces w ere l e ft next

\ 0 i \ for prosthetic work

12 • ' >art A Pr eliminary Examinati o n of till! Pa tient

I occlusion If there is excess maxillary tooth material, we will end up with an excessive OJ (sec Fig FS.8); if the excess is in the mandibular arch, then minimal

OB/OJ will exist and the cuspids will occlude in a slight class III relation

A large percentage of patients have mesial-distal tooth-size discrepancies,

approxi-mately 13.8% and 9.2% for the mandibular and maxillary dentitions, respectively I I

Such discrepancies, if left untreated, could lead to future posttreatment relapse, cially in the mandibular incisor area Interproximal reduction will, in most cases,

espe-alleviate such discrepancies

A method used to assess TSD is Bollon's analysis.1,ll If alterations of tooth size are

to be done in the upper arch, the sum of the width of the lower anterior teeth is

multiplied by 1.3 to give the dimensions of the ideal upper arch for these particular

lower anteriors.IO If alterations of tooth size are to be done in the lower arch, then the

width of the upper anterior teeth is multiplied by 775 to give the ideal lower arch.1O

If the TSD is in the posterior teeth, then they may be selectively reduced in width,

enough to obtain a class I cuspid relation (see Figs F3.7, F3.8) Interproximal redu

c-tion should be done in the upper or lower arch in order to make these teeth fit in

relation to their counterparts

3 Ameri c an Academy of Cran i o mandibular Disord ers: C ran iomandibufar {Jis o rdcrs : G uideline s fo r £~af ­

uoti o n , Diagn os is and Manag e ment M c Neill C, ed Chicag o: Quintessence Pub l ishing, 1990

4 Pa rker WS : Centric relation and ce ntri c occ lusion - An o rthod o nti c responsibility Am J Orthod

Dentofacial Orthop 74 :4 8 1-5 00 , 19 78

5 H arri s EF , and Johnson MG : H eritabili t y of c raniome t ric a nd occ l usal v ariables: A l ongitu di nal sib

a n al y si s Am J Orthod Den t of acial O rt hop 99 :258-2 6g , 1 991

6 Carlson G : Advan ces in Orthod on t ics: Seminar Se ries ( Course Syllabus) M i nneapoli s M N 1988

7 Proffit WR : Co ntemporary Orlhodonlic s St Louis, MO: C V M os b y Co., 198 6

8 Richardson ME : The role of t h e third molar in the cau se o f late l ower arch cro wding : A re view Am J

Orthod Dcnt of acial Orth o p 95:7 9 - 83 1989

9 Vadiakas G , and Viazis AD : Anterio r c rossbite co nnecti on in th e prima ry dentition Am J O rthod Den t of a cia l Orthop 1 02: 1 60 - 1 6 2, 1992

1 0 W o l ford LM : Surgica l - on h odontic oom:ct ion of dentofacial and craniof ac ia l deformiti es-Syl la bu s

Ba y lor Col lege of Denti s try, Dallas TX , 1 990

II C rosb y DR and Al e xand er RG: Th e occurrence of tooth size di scre pan cies among different

malocclu-sion gr oups Am J Orthod Dentofacia l Orth o p 95: 457 - 461, 1989

12 Bolt on WA : The clinical application of t oo th si z e anal y sis Am J Orthod Dcntofa cial Orth op 4 8:5 04

-529,1962

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A careful dental and rndiographic (panoramic or periapical) evaluation may reveal a number of

situations that need to be addressed before the initiation of orthodontic mec

hano-therapy

Ank ylosis

Ankylosis,' a localized fusion of alveolar bone and cementum, is the result of a

defective or discontinuous periodontal membrane and is apparently caused by

me-chanical, thermal, or metabolic trauma to the periodontal membrane during or after tooth eruption It occurs most often in the primary dentition (see Fig 010.8) in the

mandibular teeth, and in molars It can sometimes be detected from radiographic evidence of periodontal membrane obliteration or by a sharp or ringing sound upon

percussion and by lack of tooth mobility or soreness, even with heavy, continuous orthodontic forces '

In the primary dentition, ankylosis is usually treated by simple neglect, restoration,

or extraction.l Ankylosis of a permanent tooth, however, is more complicated if

orthodontic treatment is planned Intervention can include luxation, corticotomy, or

ostectomy I Most infra-occluded and ankyloscd primary molars with a permanent successor

exfoliate normally.2 The decreased height of the alveolar bone level at the site of the

infra-occluded primary molar has been reponed to normalize after the eruption of the permanent successor Infra-occlusion and ankylosis of primary molars docs not con-stitute a general risk of future alveolar bone loss mesial to the first permanent molars

Primary Failure of Eruption

Primary failure of eruption describes a condition in which nonankylosed, usually

posterior teeth fail to erupt, either fully or partially, because of failure of the eruption mechanism.l - S The teeth most commonly involved are the deciduous and permanent

molars, although premolars and cuspids may also be affected.$ There appears to be no mechanical impediment to eruption in these cases.' Unilateral situations occur more frequently than bilateral ones A posterior open bite, caused by a primary failure of

eruption, will not respond to orthodontic treatment; a segmental alveolar osteotomy offers the only possible treatment modality

Dia stemas

Midline diastemas arc qui e common among individuals (see Fig F4.11) Closing

them poses no problem orthodontically, but in many patients they lend to re-open,

especially ifcaused by an abnormal labial frcnum.6

14 • Part A I'fI ' fim i nar y Examinati o n oj lhe Path'nl

•

It is important to close th e space ort hod o nti ca ll y as soon as poss ib le and t he n

perform th e s ur gical procedure of ab nonnal la b ial frenum , th us allowing healing of

th e ti ss ues to occ ur with the teeth in th e ir n ew l y establis h ed positions.6 It is sugges t ed

that when the fr en um i s wide a n d attached below the mucogi n giva l j un c ti on in

ker'J tinj zed ti ssue , it often will regenerate after frenectomy ' T o preve nt t h i s from occurring, epi thelial graft from th e palate i s placed over the area on removal of t h e

frenum , preventing it s ingrowth.'

Root Re sorption

R oot resorption occurs in every patient who undergoes orthodonti c treatment I n the

m ajority of cases , it i s a mere blunting of th e r oot apices In some pa ti e nt s, it i s more

seve r e for r easons that see m to be idiopathic wit h the exceptio n of p r evio u sl y

trau-m at i zed t ee th , which are m ore susce pt i b le t o r eso rpti o n a nd l oss o f vital it y (F i g

A4 1 ).' Around 16.5% of pati e nt s have approx imat ely I mm of resorp ti on o f t h e

maxillary incisor teeth ' Maxilla ry incisors h ave been reported t o be th e m ost susce

p-t ib l e to th i s seve r e resorp ti on , w ith other t eeth less affected A r ecent stud y showed

th at 3% of patients ha v e seve r e resorption (grea t e r th a n one q u a rt er of th e root length) of bo th maxillary cent ral incisors (Fig A4 2)

Less re so rpti o n is observed in patients tr ea t ed before age II yea r s, perhaps due to a preventive effec t o f the thick layer of pre d ent i n on yo u ng , undevel o ped rool s.9 C on-

ta c t o f ma xi ll ary in c i sors w it h t he lin g ual co rt ica l plat e m a y pr edi s pose to r esorp t io n ' Cla ss III patients ar e overrep r esented in the group with seve r e r esorption '

Figu r e A4 1 Trauma to these central in c isors from a bicycle accide nt led to their severe root resorption and loss of vitality

FI~

of roo

,

A4 , 2

Figure A4.2 R eso rpt ion o f ce ntral incisor t ee th after 2 years

of o rthod o nt ic treatme nt One quarter t o one t hird o f th ese

treatment time is the most significant factor for occurrence of root shortening In a

recent long-tenn evaluation of root resorption occurring during orthodontic trea

t-ment, it was shown that there are no apparent changes after appliance removal except

remodeling of rough and sharp edges.!2

Impacted Cuspids

Impaction of the cuspid tccthll- 20 is caused primarily by the rale of root resorption of the deciduous tccth, disturbances in tooth eruption tooth size/arch length discrepan-

cies, rotation or trauma of tooth buds, premature rOOI closure, ankylosis, cystic or

neoplastic formation, clefts, and idiopathic causes Most of the impactions arc unil

at-eral and on the palatal side 16 The evidence of maxillary impaction ranges from 0.92%

to 2 2% ; maxillary impaction is twice as common in females than in males, I6 The

incidence of mandibular impaction is much less, 0.35%,16 Impacted cuspids may

cause resorption of the adjacent incisor teeth; thus, their extraction or uncovering and

movement into thc dental arch is necessary (Fig A4.3) Potential incisor resorption cases from impacted cuspids are those in which the cuspid cusp in periapical and panoramic films is positioned medially to the midline of the lateral incisor (0.71 %).!6

The risk of resorption also increases with a more mesial horizontal path of eruption.2!

16 • J'a rt " P rrii m mar} ' E xa m i nal ioll of/h I ' I ' m i m l

M.3 Figure A4 3 An impacted c uspid ha s c aused almost c omplete resorption of the lateral incisor tooth and signifi c ant de- str u c ti on o f th e ce n tral in ciso r tooth

Surgical uncovering of these teeth is the standard treatment procedure, followed by direct bonding of an orthodontic bracket onto the tooth and mechanical traction with

elastics or springs to bring the teeth into the arch (see Fig F4.58) An apically repositioned nap for labially situated cuspids is recommended I Adequate attached gingiva need be present (or surgically placed) to avoid mucogingival problems Wire

ligation ("lasso" type) instead of direct bracket placement onto the uncovered tooth is prohibited because it leads to loss of attachment and to external root resorption and ankylosisY In addition, any surgical exposure beyond the cement- enamel junction

leads to bone loss

Treatment of cases with impacted cuspids is quite lengthy, depending on the

position and orientation of the impacted tooth in the bone.'6•'7 It may take between

12 and 30 months Also, at the end of treatment, these teeth will show the presence of

a 5- to 7-mm pocket, usually on the distal side They display significantly more loss

of periodontal support on the buccal and palatal surfaces than do normal teeth.11 Excellent oral hygiene will preserve these teeth throughout life without further sequelae

An alternative to surgical uncovering and lengthy orthodontic treatment of pacted teeth is the autotransplantation of these teeth Autotransplantation should be performed at a stage when optimal root development of the transplant may be expected; namely, one half to three quarters of the full root length I' When transplan-tation is performed at an earlier stage of root development, the final root length may

im-be shorter than desirable If autotransplantation is performed at a later stage of root

development the risk of root resorption increases The surgical procedure should be

as atraumatic as possible and requires a surgeon well acquainted with the method

Teeth transplanted with incomplete and complete root formation show 96% and

15% pulp heal ng, respcctively.'9 The size of the apical foramen and possibly the

avoidance of bacterial contamination during the surgical procedure are explanatory factors for pulpal healing Trauma to the periodontal ligament (PDL) of the trans-

plant is the explanatory factor for the development of root rcsorption '9

.'" in&!

cu

Cliapll'r 4 Radiographic f : l'ulliuli o n • 17

A rairly new technique, transalveolar transplantation, is used to remove large

amounts or bone with a bur except ror a thin layer close to the root surface.20 This

bone is then very gently removed with an elevator to avoid damage to the cementum

The tooth is stored in the socket throughout the operative procedure Finally the

cuspid is moved through the alveolar process into its determined position A sectional

arch wire is used to stabilize but not immobilize the transplanted cuspid Sometimes,

grinding or the antagonist tooth is required to avoid traumatic occlusion A postope

r-ative orthodontic appliance check is perrormed I week later, when the sutures are

removed Further orthodontic controls are performed every 2 weeks ror 6 to 8 weeks

Tooth Transpositions

A4.4

Transposition has been described as an interchange in the position or two permanent

teeth within the same quadrant or the dental arch.22-n The maxillary permanent

cuspid is the tooth most rrequently involved in transposition with the first bicupid 22,2 ~ less orten with the lateral incisor (Fig A4.4).12·24 The retained deciduous

s-cuspid may be the primary cause for deviation of the permanent cuspid from its

normal path of eruption

If the mandibular cuspid and lateral incisor have already erupted in their

trans-posed position, correction to their nonnal position should usually not be attempted.22

Alignment in their transposed position with reshaping of their incisal surraces will n01

damage the tccth or supporting structures and will present an acceptable esthetic

result If one or the transposed or adjacent teeth is severely affected by caries or trauma or if there is a severe lack or space, extraction of that tooth should be considered.22

•23 Ir tooth movement is undertaken to correct the transposition, in order

to avoid root interference or resorption during treatment and to prevent bony loss at

the cortical plate of the labially positioned cuspid, the transposed tooth (premolar or

lateral incisor) should first be moved palatally, enough to allow ror a frce movement

of the cuspid to its normal place.22.23 This last method is the least desirable treatment

of choice

Figure AU Transposed maxillary right cus pid as it i s

erupt-ing dis tal to the first bicu s pid Note th e retained primary

cuspKl

18 • Part A Pr elimi/Jaf}' Examinal i on oj/ he Pal iem

Supernumerary Teeth

Supernumerary (extra teeth) or congenitally missing teeth occur Quite frequently among patients.u The most common situation of a supernumerary tooth is a meso-dens between the central incisors, which may prevent their nonnal eruption The most frequent missing teeth are the upper laterals (see Fig F5.30), followed by the

lower second bicuspids, the upper second bicuspids, and lower incisors Of course, the third molars (wisdom teeth) arc missing in a large percentage of the population

Third Molars

The role of mandibular third molars in the relapse of lower anterior crowding after

the cessation of retention in orthodontically treated cases has provoked much specu· lation in the dental literature over many years.21 Most practitioners are of the opinion that third molars sometimes produce crowding of the mandibular anlerior teeth.2

• A number of studies over recent years have substantiated very clearly that the presence

of third molars does not appear to produce a greater degree of lower anterior crowd· ing than that which occurs in patients with no third molars.21.29 Therefore, the recommendation for mandibular third molar removal with the objective of relieving interdental pressure and thus alleviating or preventing mandibular incisor crowding is not justified 28,29

4 Ireland AJ : Familial posterio r o pen b it e: A primary failure of eruption Br J Onhod 18:233-237 199 1

5 Nashed RR and Holm es A : Case report - A pos t e rior open bit e Br J Orthod 1 7: 4 7 - 53, 1 990

6 Bishara SE: Management o f diastemas in o rthod o nt ics Am J Onhod 6 1 :55- 6 3, 1 972

7 Tak ei H: Periodontal prob l e m - solving for ort hod ontics Summa ri zed b y Turle y PK Pacific Coast

Societ y of O rt hodon ti sts Bullet i n Spring, 34 - 36, 1 991

8 unge L, and L inge 80 : Patient characteristics and tre-oltmen t variables associated with api ca l root resorption during orthodontic treatment Am J Onhod Dcnt o facial Onhop 99 :35 -43 199 1

9 Kale y J, and Phillips C; Factors rel ated t o root resorp t ion in edgewise practi ce Angle Onhod

61:125-131 1991

10 Hickham Jt! : Oire<:tional forces revisited J Clin Orthod 2 0 :626- 637,1986

II McFadd en WM , Engstrom C, Engstrom H and Anholm JM : A study of th e relation s hip between incision intrusion and root shorteni ng Am J Orthod Dentofacial Onhop 96 :3 90-39 6, 1989

12 Remington ON J oondeph DR , Artun J , Riedel RA , and C hapk o MK : Long-term ev aluati on of root resorpti o n occ unin g during orthodontic treatm e nt Am J Orthod Dcntofacial Orthop 96: 43 - 4 6, 1989

13 Bishara SE , K o mmer DO McNeil MH , Mantagana LN Oestler U , and Y oun gqui s t HW: ment of impacted c uspid s Am J Orthod 69 : 37 1- 387 , 19 7 6

Manage-14 Vanarsdall RL, and Co m H : Soft-tissue management of labially positioned un eru p t ed tee th A m J Onhod 72:5]-64 , 1977

1 5 Bo yd Rl : Clin i ca l a ssess ment of injuries in orthodon t ic m ove ment of impacted t eet h Am J Onhod

82 : 4 78- 486 1 982

16 Bishara SE : Impa ct ed maxillary canines : A review Am J Onhod Dentofa ci al Orthop 10 1 : 159 - 17[ ,

1992

1 7 Wisth PJ, N o rderal K , and Boe OE: P eriodontal status of o rthod ontically treated impacted ma~iI1ary

c uspids Angle Orthod 46 : 69 -7 6 1976

18 Lagerstom L and Kristcrson L : Influenc e of orthodon ti c treatment on root developm e nt of

autotrans-planted prem o l ars Am 1 Orthod 89: [46 - 1 5 0 , 1986

19 Andreasen JO Paulsen HV , Vu Z Ahlqui s t R , Bayer T and Schwartz 0: A long - t enn s tud y of 370

autotransplantcd premolars Eur J Onhod \2 : 3 - 50, 1990

20 Sagne S , and Thilandcr B : Transalveolar transpla.ntat io n of maxillary cu s p ids A f o ll o w - up study B r 1

Orthod 12 : 14{I - 14 7, 1990

2 1 Ericson S a nd Kurol J: Resorpti on of maxil lary la t e ral incisors caused by ec t opic e rupt io n of the

c uspids Am J Orthod Dent o facial Orthop 9 4 : 503 -5 1 3, 1 988

22 Shapira Y , and Kun i nek MM : Tooth transpositions - A review o f the l iteratu re and treatm e nt co n erations Angle Orthod 59:271-276, 1989

sid-Chapler 4 Ra diographic El ' uillufion • 19

23 Laptook T and S illin g G: C uspid tran sposition - Approaches t o treatment J Am Den t Assoc

107 :7 46 - 7 4 8, [9&3

2 4 Gholston LR , and William s PR : Bil ate r al transpo sition of m axi lla ry cus p ids and lateral incisors : A rare

con dit io n Journal of Dentistry for Ch i ldren 5 I :58 - 63 [984

25 J os hi M R, a n d Bhatt NA: Cuspid transposi t io n Oral Surg Oral Med Oral Path ol 3 I : 49 -5 4 1971

26 U nd ergraduate Syllabus U n ivers i ty of M in n esota O rt hodon t ic Department , M i nneapolis MN 1 989 ,

27 , Ka p lan RG : M andi bular t h ird molars and postretenti o n crowd in g Am J Orthod 66 : 4 11 - 430 1974

28 Ades AG , J oo ndeph DR lillIe RM and OJapko MK : A l o n g-te nn Study of th e re la t o n sh i p of th ird

molars to c hanges in th e mandibular dental arch Am J Orthod [)entofacial Orthop 97:323 - 335, 1990

29 Southard TE Sout ha rd KA, and W eeda LW: M esial force from unerupted third mol a rs Am J Orthod

C lla

The Temporomandibular Joint

The key to understanding temporomandibular disorders (TMOs) is in the differential diagnosis

of joint (internal derangement) versus muscle pathology (myofacial pain) or a

combi-nation of the tw o , l - 6 Internal derangement of the temporomandibular joint (TMJ) refers to any abnormal anatomic relation between the three parts of the TMJ, namely, the condyle, the disk, and the articular fossa.1.4,6 The most common internal derange-

ment is that of anterior disk displacement, which results in the clinical sign of "clicing" or "popping" as the condyle snaps over the posterior band of the disk and on to

k-it during mandibular movements' (stage I) The click may again be audible in a

closing movement as the condyle slips off the back of the disk, and this is termed a reciprocal c1ick.I • • 6 This clicking on and off the disk is called anterior disk displace-

One should keep in mind that as much as 50%, if not more, of the population has

one sign of joint dysfunction (noise, tenderness, etc.); the female to male ratio ranges

from 3: 1 to 9: 1, and only 5% of the patients with signs and symptoms are in need of

TMJ therapy.6 During the TMJ examination of the patient, the clinician should look

for possible sore muscles (in the neck and mouth area) and any "clicking" noises (with

the usc of a stethoscope or digital palpation), as well as any deviation on opening and

c1osing7- 9 (the mandible will deviate toward the side of an anteriorly dislocated disk),

any signs of bruxism and clenching (it is nighttime clenching that in many cases

results in morning headaches), and the overall strain-level status of the patient

The mouth should be able to open anywhere between 35 to 45 mm Onen, the

patient may have a "closed lock" where he or she cannot open the mouth because the displaced disk is hindering mouth opening (stage III) At other times, the patient

cannot close the mouth, "open lock," because a posteriorly displaced disk may not

allow the condyle to return to its position in the fossa.7- 9 This may occur in the

orthodontic office during bracket placement where the patient's mouth remains open for a long period of time If the joints demonstrate a high level of mobility ("loose

joint"), it should be noted in order to avoid overstretching the already compromised

ligaments.· Any crepitus joint sound (a cracking sound indicating a rough condyle,

disk, or eminence surface) may be the result of direct long-term bone contacts

between the fossa and the condyle"· (stage IV) Unless the condition stabilizes at this

point, pain and degeneration of tissues may develop, resulting in severe dysfunction·

(stage V)

The management of TMJ disorders ranges from behavior modification,

pharmaco-therapy, and palliative home care to physical therapy, orthopedic appliance therapy,

and surgical treatment.··6 The description of these is beyond the scope of this text

•

22 • J 'a r l A Pr elimifJa r, ' E xam;fJ(1/;QfI oj/he Pa /iem

AS 1

Figure AS 1 An i nterocclusal :lppli:ln cc (splint)

Exce ll en t sources a r e ava i lab l e i n the l t era tur e on s u ch t rea t ment modalit i es ' - 6,10

Sc lf -<:are , i nclu d i n g a soft die t ( n o g u m or c affei n e) , l mited f u n c tion , hea t , and self- m assage , s h o u ld be ins tit uted 2 D isk di sp lacem e n t may be an ada pt at i on t o s t ab il-

i y a n d s h o ul d n ot n ecessa ril y be v i ewed a s pat h o l ogic 2 It is mos t p robab ly d u c t o a

s l ow a lt era ti o n a n d no t t o traum a 2

No ort h odont i c t rea tm e nt s h o u ld be i n i ia t ed befo r e poss i ble TMJ pain or d ys func

-t io n i s u n der con t rol Some tim es th i s can be addressed w it h si m u lt a n eou s ort h odo nt ic

t herapy , bu t i n n o case s h ou ld it be postponed u n t il aft e r o rt hodon ti c tooth

move-me nt In m os t cases , an i n t eroc clu sa l a p p li ance (s pl i nt ) genera ll y i mp r oves t h e TMJ

s tatu s o f th e pa ti e n t 1I An int eroc clu sa l ap pl ia n ce is ge n era ll y co n sidered to be a

re m ov abl e d ev i ce m a d e of h ar d acry l ic r esi n t hat fit s between the maxi ll ary and

ma n d ib ul a r t cc t h (Fig AS, I ) It s ta bi li zes an d i mproves t h e f u nct i on of t he TM J and

t he m ast i catory sys t em a n d pro t ec t s t h e tee th f rom a tt ritio n and the TMJ fro m

t ra umatic l oadi n g In so m e in s t a n ces , h oweve r , T MJ s u rgery i s th e tr ea t me nt moda lit y

of c h o i ce , w h ic h is so m e tim es com bin ed w ith o rth ognat hi c s ur gery 1 2

T h e clinic i a n mu s t mak e every possib l e a tt e mpt t o e n sure t hat o rt hodont i c m chano th e r apy does no t aggravate a p a t ie nt 's comp r omised T M J status 13

e lj In t he

tr ea tm en t of class II pa ti e nt s with d eep b ites a n d hi gh cus p s, a fl at plate of a c ry li c t h at

is pla ce d over th e occl u sa l s u r fa ces of th e l ower pos t e ri o r t eet h in conjunc t io n w ith fixed a ppli a n ce t h era p y ma y pre v en t a n y unn ecessary d is tal p ress u res on th e co n -

d y l es.7 One must be c a ref ul , h o w eve r , no t to crea t e pos t e r io r ope n bi t es I n t he

t rea tm e nt o f class III pa t ien t s , chin-cap an d class 111 e l as ti cs th a t exe rt di st al pressure shou ld no t be used du ri ng s l eeping hours , w h e n t h e mu sc l es are r e l axed a n d t here f o r e

w h e n th ere is m ore d is tal p ress u re o n th e co n dy l es.7 In th e re t e nt io n p h ase of a d eep

b it e o n e m ay co n s id e r th e u se o f a H aw l ey b i e p l at e t o p reve nt th e b it e f r om ge tt i n g

d ee per a n d thu s exe rtin g di s tal p ress u re o n th e c on d y l e ? TMJ d ysfu n c ti o n sy mpt oms a ft e r ort h odo nt ic th era p y m ay occ ur in an in div i dua l case, b u t in ge n e ral th e r e see m s t o be no con n ec ti o n be t wee n functio n al d i s t ur ban ces

a nd w e ll-pl a nn ed o rth odo nt ic th e rap y.16 Scvem l good , sc i en t ific , co nt ro ll ed , l o n g- t e rm

s tudi es indi ca t e th a t o rthod o nti cs i s n o t a ca u se o f TMJ d ys fun c ti o n ,17 - 19 No da ta

e xi s t t o s u p port th e no t io n that o rth odo nti c tr ea tm e nt o f c hild re n or ad ult s pr eve nt s

o r l owers th e risk of subseque ntl y d eve l o pin g TMD 20 P os t o nh odo nti c pa t ie n ts w ho

we r e t rea t e d in various tm di ti ona l w ays of ort h odo nt i c tr ea tm e nt h ave no m ore T MD

sy mptom s t han do peo pl e w ith unt re at ed m a l occ lu sio n o r pe o pl e wi t h n o rm a l occ lu

-s i o n s 20 I f T MD sy m p t o m s ari se durin g o rt hodon ti c t r ea tm en t, observa t io n an d co m

-m o n se n se are th e bes t a ppr oac h es.20 If th e s y mpt o m s a r c pa inf ul , it m a y be n ecessary

A S :

AS 2

Cbapler 5 Tlrl' T''nr[IQTomo"dibulur Joint • 23

to modify active therapy: reduce forces, stop headgear, eliminate direct mandibular

distalizing forces, minimize interareh elastic use, and eliminate gross occlusal

coverage splints These measures will allow sore muscles and joints to recover so

treatment may proceed.20

Orthodontic treatment does not appear to pose an increased risk for development

of TMJ sounds or symptoms, irrespective of whether extraction or nonextraction

treatment strategies are Used 21 The original growth pattern that caused the teeth to be

selected for extraction-rather than the extraction itself-is the most likely factor responsible for the frequency of TMD reported years later.22 Bicuspid extractions and

subsequent orthodontic treatment do not lead to irreparable damage of TMJ mucles.23 Condylar position is unrelated to extraction treatment and to bite depth.2<I It

s-has been shown that the claim that bicuspid extraction and incisor retraction must, of

necessity, lead to unsightly profiles and distal mandibular displacement cannot be

supported.2S Persons who have undergone orthodontic treatment have a significantly

lower clinical dysfunction index than those who have nol.26 Orthodontically treated

patients arc not more likely to develop TMD signs while undergoing treatmentY A

relation between either the onset of TMJ pain and dysfunction and the course of

orthodontic treatment or the change in TMJ pain and dysfunction and the course of

orthodontic treatment has not been cstablished.2S

At the end of the orthodontic treatment, the patient should be left with a healthy,

functional occlusion in centric, excursive, and protrusive movements.29•30 Centric occlusion (maximum intcrcuspation) should coincide with the centric relation posi-

tion (rest position) (Fig AS.2) In excursive movements on the working side (the side

to which the mandible is moved when food is chewed), the max.illary cuspid should

cOntact the mandibular cuspid, whereas no posterior teeth should contact at any point (mutually protected occlusion) (Fig AS.3) In the event that cuspid guidance cannot

be achieved (due to severe wear, absence of maxillary cuspids or cuspids in place of

laterals) the maxillary buccal cusp inclines of the posterior teeth should be in even

contact with the mandibular buccal cusp inclines of the lowers (unilaterally balanced occlusion or group function) In both cuspid guidance and group function, there

should be no tooth contacts on the side opposite the working side (nonworking or

balancing side) In protrusive movement, there should be no posterior tooth contact

A5 3 Figure AS.2 Pati en t in centric occl u s ion that co in c ides with

ce ntri c relation

Figure A5.3 C u sp id guidance in exc ursiv e m ove ment ( work ing s id e) Note the clearance or post e ri or tooth co nta cts There i s also pos terior di sc lu sion of tee th on the other

-(balancing) sid e

24 • PIIr' A Prelim i n ary E x am i Ja /i o n o f /h e P a /ienl

when the maxillary six anterior teeth contact the eight most anterior mandibular tccth

in an edge-to-edge position (in both cuspid guidance and group function scenarios) (F;g A 5 A )

3 Williamson EH : Occ lusi o n and TMJ d y s function J a in Orthod 1 5:3 9 3 - 4 10, 198 1

4 Ok eso n JP : M an a g emen t oj T e mpo ro m a nd ib u la r D is order s an d Occ/ ll s i o n 2 nd ed S I Lou i s: C V

Mosb y C o , 1 9 89

5 M o hl NO Zarb GA, Carlsson GE and Rugh JD : A T e xt book of Occiruion C h ic a go : Quint esse n ce Publishing, 1988

6 Ameri can Acad e m y of C raniomandibula r Disorders : Cr an i o m a n dibula r JJi s ord er s: Guideline s f or E ' · a/·

li D/ i o n , D i agn o si s a n d Man age m ent M c N eill C, cd Ch icago : Qu i nt esse n ce P u b l ishin g, 1988

7 Williamson Eli : Occ lus io n a nd TMJ d ys function Jain Qnhod 1 5:3 3 3 - 350, 1 8 1

8 Williamson EH : Occlusion : Understanding or mi s understanding Angle Onhod 46:86 - 93 19 7 6

9 W ya tt WE: Preventing adve~ eff ects on th e TMJ through o nhod o nti c treatm e nt Am J O nhod Denl o facia l Orthop 9 1: 493 - 499 , 1 9 87

10 N e ff PA : Occ l u s ion and function Georgetown Unh ' e rsit y Sch ool of Den t s t ry, Wa s hingt o n , DC , 1 975

11 Bocr o RP: The physiology o f splint th e rap y: A lit e rature review Angle Orthod 5 9 : 1 S -180 19 89

1 2 Bell WH: Mod e rn Pra c/ i c e in Orth og nath ic and It(> co n.\·tru c/ il' /, Surger y v o l s 1 - 3 Philadelphia : W B Saunders Co • 1 9 2

1 3 Roth RH : T e mporomandibu la r pain - Dysfunction and occl usal rel a t io nsh i ps An gle Onhod 4 3: 13

6-I S3 , 1 973

14 Roth RH : Fun e tional occlusion for th e onhodontisl Jain Orthod Pan 1 ,25: 3 2 - 5 1 ; Part 2 , 25 : 100

-1 23: Pan 3 , 2 5: 174 - 198 ; P a n 4 , 2 5 :2 4 6 - 2 6 5, 1981

15 R ot h RH , and Ware WH : Orthogn a thi c t rea tm e n t in pat ie nt s wi t h t e mporom a nd i bular j oin t

pain-d ys function J a in Orthod 14 : JOiI - 12 0 , 198 0

16 K c b K, Bak o pul os K , and Witt E : TMJ funct i on with and without o rthod o nt i c t rea tment Eu r J Orthod 13:192 - 196 , 1991

1 7 Bak er RW , Catania lA , and Baker RW , Jr : Occl usio n as it re lat es t o TMJ : A s tud y o f t he l it era ture

NY Sta t e Dent J Jan ua ry 57 : 3 6 - 3 9, 1 99 1

1 Sad o wsk y C , a nd Polson AM : TMD and funct i o n al occ l us io n after onh odo ntie treatm en t : R es ul ts of

tw o l o ng·term studies Am J Onhod 86 :3 86 - 390 , 1984

19 Sad o wsky C , and SeGol e E : Long-t e rm s tatu s o fTMl fun c ti o n and fun ct i o nal occ lu sio n after o nh dont ic t rea tm e n t Am J Onhod 7 8 : 201 - 2 1 2 , 1980

o-2 0 Greene CS : Onhodo n ti cs, orthodon t ist s and TMD Summarized by Cro u e h D L P aci fi c C oa s t Socie t y

o f O n hod o n ti s IS Bulletin , Wint e r , 33 - 35, 1990

Chaptt'r 5 The TemporO llla/ldibular Join{ • 25

2 1 Sadowsky C Theisen TA and &tko l s E I : O n hodon tic t reat men t and TMJ sounds -A longit udinal

Sl ud y Am 1 Orthod Dento f acial O rt hoJl 99:44 I - 44 7, 199 1

22 Dihbets JMH , and van der Weele LT: Extrxtion onhodonti e tre a tm en \ and cran iomandibular dys

function Am J Orthod Dentofacial Orthop 99:210-219 1991

23 Kundinger KK Austin S P, C hristensen LV Donegan SJ , and Ferguson 01: An evaluation ofT MJ and

jaw muscles after orthodontic treatment involving premolar extractions Am J Orthod Dentofacia!

Orthop 1 00 :110- 11 5 1991

24 GiancHy AA Hugh es HM , Wo hlgem uth P and G ildea G: Co ndylar position and extraction treatment

Am 1 Orthod Dc:ntofa cia l Ort hoJl 93:210 -2 05 1988

25 Lueck e PE III and J ohnsto n LE, Jr : The effect of maxillary fiJ"!it prem o lar extraction and incisor

retraction on mandibular position: Testing th e central dogma of "functional orthodontics " Am J

O rt hod Den t of acial Orthop 1 01: 4 - 12 1 992

26 Egennark I and ThiJandc r B : Cra niomandib ular di so rd eB with §pCCial reference to orthodon tic trea t

-m en t: A n evaluation f o m child h ood to ad u lthood Am J Ort hod Dent of a cial Orthop 101 :28- 3 4 , 1 992

27 Hi rata RH H e ft NW li ema ndez R and King G J : Longitud i nal study of signs of te mporomandibular

disorders ( TMD) in onhod ont icall y lrealed and nonlTCatOO gro ups Am J Orthod Den to facia l Ort hop

101 :35- 40 ,1 992

28 Rendell lK Norton LA and Gay T ; Orthodontic t rea tm ent and temporomandibular joint d isorders

Am J Orthod Dentofacial Orthop 101:84 - 87 1992

29 Parker WS: Centric relation and ce ntric occlusion - An orth odon ti c res pon sibi lity Am J Orthod

74:481 - 500 1978

30 Andrews LF : Th e six k eys to normal occ l usion Am 1 Orthod 62:296 - 309 1972

e ll f e r

A thorough functional evaluation is an essential part of the development of the patient's

stomatognathie problem list Habits should be evaluated carefully, keeping in mind that approximately 50% of children without malocclusions have what is considered to

be bad habits I The duration and intensity may be more important than the actual presence of an abnormal condition.'

Nasal obstruction, causing mouth-breathing and a lowering of the mandible and tongue, may produce remarkable changes in the dental and facial relationships! (Figs A6.1 and A6.2) If, after the age of 5 years, especially in the early mixed dentition

stage of 6 to 8 years of age, the child has difficulty breathing through the nose, a

referral to the otolaryngologist would be most appropriate Although the liter.Hure is replete with statements that airway impairment alters facial and dental growth, there is

substantial evidence to the contrary.)

In a recent study of mandibular and maxillary growth in boys after a changed

breathing mode 5 years after adenoidectomy, it was found that there was almost a

4 mm greater mandibular growth (statistically significant) but no change in maxillary growth direction.· Conversely, there was also no change in the breathing mode in 20%

of the sample A concurrent studyS on the relation between vertical dentofaeial mor

-phology and respiration in adolescents concluded that different breathing modes may

be behaviorally bascd, rather than airway dependent, and that intervention to alter the

nasal airway and thus to influcnce dentofacial growth is unjustified What may be an

excellent therapeutic modality for one patient docs nOI indicate that it will have the

same effect in the majority of patients Although there seems to be a weak tendency

among mouth breathers toward a class II skeletal pattern, increased anterior facial

height, high mandibular plane angles, and retroclincd incisors-all characteristics of a long face-a more thorough anaJysis of respiratory pattern is required to support the dedsion for clinical intervention.6

28 • PBn A Pr e/ im i nar , Ex a m i na li on oflh e Pallenl

Figure A6 1 Severe nasal obstru c ti on has led to mouth

-breathing and s ignificant c h a n ges in thi s pat ient's facial

c haract e ri sti cs, suc h as hypotoni c res t posi ti o n and lip

2 Linder Aronson 5; Nasore.ylira~ ~ AD iVlbtldt:wJ ri ) 9.' tkl~: i.'Y" -J;:.1 ~ <lJ'"" IW.-In"

Graber lW, cd 51 Louis : C V MosQv Co_ 1986 116 - 1 2 1

J Melsen B ; CI/rrml Co nf ro vI'rJ · i( ' f in Ortlwdunli cs C hi c ago; Quintessen c c Publishing, 199 J

4 Woodside DG, Lindcr - Aronson S, Lundstrom A , and McWilliam s J : Mandibular and ma~illary growth aft c r c hanged modc of breathing Am J Orthod Dent o facial Orthop 1 00 : 1- 18 199 1

5 Fklds IIW , Warren DW , Black K , and Phillips CL: Relationship between \"cnical dentor aci a l m o rphol

ogy a nd r espirat ion in ad o lescen ts Am J Orthod Dcn t o facial Orthop 99 : J 4 7 - 15 4 1991

6 Ung N Koenig T , Shapiro PA Shapiro G a n d Trask G : A qu a nl i ta t i\ ' c assessment of respir u o ry patterns and their e lf ects o n de ntofacial dc~"CIopm ent Am J Orthod Den t of acial Onh o p 9 8 : 523 - 532

1990

c

E

Ciia

Oral Hygiene Considerations

Enamel demineralization (Fig A7.1) is associated with fixed orthooontic therapy in an ex·

tremely rapid process that is caused by a high and continuous cariogenic challenge in the plaque developed around brackets and underneath ill·fitting bands! (Fig A7.2)

teeth, it is not surprising that gingival inflammation tends to increase in orthodontic patients as well.l -Ii

very important throughout the duration of orthodontic treatment.l - 4 Proper brushing

and flossing three times daily is recommended, followed by fluoride mouth rinses once

a day.5 The combination of daily brushing with a fluoridated dentifrice, coupled with

daily rinsing with a fluoride wash provides complete protcction for the orthooontic

at risk.7 Toothbrushing with a relatively new electric, counterrotational power brush is highly advisable A rotary electric toothbrush is more effective than conven-

-ing orthodontic treatment with fixed applianccs.B A recent study that compared

electric and manual toothbrushing found that the use of the electric system resulted in

overall lower plaque scores.2 Another study of the effectiveness of the new appliance

months with the electric counterrotational toothbrush than following brushing with the

long term as well; a study showed that children who received onhodontic treatment had a greater reduction of plaque and gingivitis than children who did not.' This was related more to behavior factors than 10 improved tooth alignment.'

Orthodontic treatment during adolescence has no discernible effcct on late perio

-dontal health.' In the absence of compromising conditions (e g high decayed

-missing-filled (teeth) [DMF] scores, periodontitis), adult patients are not inherently

more likely than adolescents to lose dental support (e.g crestal bone height) during

pro-gression of marginal periodontitis will occur due to orthooontic tooth movement

and that the patient visits the periodontist every 3 to 4 months for check_ups.11-11 Oral irrigators generally enjoy a high mle of compliance with adults.l ! Oral rinses such as

Listerine, can be effective adjuncts if compliance is good.!! Cases with unmanageable

gingival inflammation can be put on a 6-week regimen of rinsing with Pcridex (

Proc-tor & Gamble) twice daily 11 (Figs A7.3 and A7.4) Dental cleaning will be needed at

the end of the 6 weeks 10 remove stain II Surgical treatment is generally employed for

definitive pocket reduction postorthodontical1y In addition, although grafting before orthodontics to prevent recession of prominent lower anteriors is highly recom-

-treatment patient because most recession occurs quickly and then stabilizes.1i Bony

30 • Pllrl A Prel imina r y £ X aminat ioll of/h., P ati ent

Figure A7 1 Severe enamcl demineralizati on and white spo t

formation due to lack of proper oral hygiene after 2 years

of orthodon ti c th e rap y

Figure A7 3 Severe gingival infl ammation, des p ite th o r ough

brushing This patient was p la ced on Peridex ( Pr octor and

d ernea th the soft-tissue overgrowth

dehiscenccs can be created during the treatment phase, especially with a thin alveolar

process, by inflammation or overzealous brushing6 (Figs A 7.5 and A 7 6)

During orthodontic treatment, forces should always be kepI within physiological limits,12 with the appliances and the mechanics used as simple as possible.6 In general,

the forces used in adults should be kept at a lower level than those used in children Light , continuous, intrusive forces should be maintained during tooth displace-

ment.14,15 When dealing with teeth with bony defects, especially in the anterior regions

(i.e , flared upper incisors with palatal bony defects), it is advisable to consider

me-chanics that will intrude those tceth.14,u Even if no intrusion takes place, this intrusive

force may negate the effects of the extrusive component 14 If the onhodontist is contemplating bodily movement of teeth into areas of intrabony pockets, it is often

prudent for the periodontist to do an open debridement procedure to prepare the root

surface adjacent to the pocket 16 Bodily movement of teeth can enhance bone growth

and reattachment if the periodontjum is properly prepared,"

Figure ease ,

ment

Figure A7.5 This patient, who has ex t e n sive periodontal

dis-ease, would not be a good candi dat e for o rthodontic treat

-ment

C hap[~r 7 Orallly!-:il'lll' Conside rati ons 31

Figure A7.6 Ovenealous brushing in combination with a prominent occlusion and thin tissues has led to gingival recessio n gingiva l clefts and tooth abrasions

Edentulous areas of the mouth need special attention during the treatment-planning phase, especially if attempting to move teeth through these spaces,11.I1 When attempt-

ing to close the edentulous space of a lost first molar by mesial and distal movements

of the second molar and premolar, respectively, one should expect a definite loss of bone averaging more than I mm around the second molar and 0.5 mm around the

premolar tooth, 7 As much as 4 to 5 mm of reduction in vcnical bone height can OCC Ur.17 Closed spaces are difficult to maintain in these patients as well," In addition

the longer the treatment tenure the greater the amount of root resorption of the second molar,·7 • 1 Although younger patients respond more favorably older patients seem to resist the opposition of new alveolar bone.'7

In cases of overerupted maxillary molars, where the use of conventional fixed appliances would lead to undesired extrusion of the adjacent teeth (extrusion happens

much faster than intrusion), a single-stage osteotomy is used to reposition the volved tooth with its surrounding bone at the proper level 19 Onhodontic tooth movement with sectional archwires will stabilize Ihe result before the bone heals

in-completely,,9 In cases where teeth need to be extruded, ample time needs to be given for "bone fill-in" around the new position of these teeth (1 mm/month),20

In patients with mild incisor irregularity or anterior tooth size discrepancies, proximal enamel is removed during orthodontic treatment, and the roots are brought into closer proximity, In other patients with unusual crown/root morphology, root proximity is inevitable in order to produce alignmenl of the crown, The clinician

inter-need not be overly concerned, because these situations do nOI seem to result in a higher predilection for periodontal brcakdown.2'

32 • l 'B rt A Preliminary Examiltalion oflhe Pmicnl

A 7.7

Finally, one should be very careful in cases with a prominent dentition relative to

the alveolar cortical plate with thin, overlying sort tissue and inadequate oral hygiene

Recession can occur quite rapidly The donor site should be carefully evaluated for

the existence of fenestration or dehiscence22 (Figs A 7.7 and A 7 8)

A7 B

Figure A7 7 Severe g in g i va l recess io n of a ll t h e l owe r a n

te-rio r tee th tha t was created wi th in a f ew m o nt hs of o nh

o-do nt ic trea tme nt T hi s was a result o f t oot h m ove m e n t in

a n en viron mc nt w i h poo r o ral h ygie n e, p romi ne nt r oo t s,

4 D avies TM , Shaw W C, W orth ingt o n HV Ad d y M D ummer P , and Kingdon A : Th e effect o f ort h odontic t rea t me n t on p l aq u e and gi n giv i tis A m J Ort h od Dentofac i al Ort h op 99: 155 -16 2 1991

5 S h annon I L: P revention of deQ.lcifica t io n in ort h odo nt ic patients J ain Orthod 15 :695- 705, 1981

6 Artun J : Long- t cnn periodontal response to o rt hodon t ic treatm e nt -S ummary b y H awlc y B P acific

Coast Society of Orthodontists B ulletin, Spring 4 2 - 4 3, 1991

7 O'Reilly MM , and F ea t hers t one JOB : De m inera l iza t ion and remineralil.a t ion aro u nd orthodontic pliances : An in vitro study Am J Ort hod Dentofacial Orthop 92 : 33 - 40 , 1987

ap-8 Boyd R L, MUTnlY p and R obe rtson P B : Eff ec t of rOlary electric too t hb ru s h venus manual t oot h brush

o n pe ri odonla l sta t us d u ri n g ort h odo n t c t rea t me nt Am J Orthod Ocn tof a ci a l O rt hop 96 : 3 4 2-347,

1 989

9 P olso n AM , Sub t e n ly JD H e it ner S W P o l so n A P , Sommers E W, I k er HP, and Reed B E : Lon g-ter m

periodo n ta l sta t us a n c r o rth odon t ic t rea t m en t A m J Orthod Dcn to fa ci a l Orthop 93 : 5 t -58, 1988

10 fl anis EF and Bak er W C : Loss o f roo t le n gth and c res la l bone height be f ore and during t rea t menl in adolesce nt and ad u lt o rth odo n tic pa t ie n ts Am J O n hod Oc n to f ac i al O rt hop 98:463-469, 1 990

I I Boyd R L: Ca n ad u l ts wi th pe ri odon tit is be lreated o n hodon t ica1J y? Sum m ary b y Qu in n R S Pacific Coast Socie t y of Ort h odo nti sts Bull e t in , Spring 48 - 49, 1 991

1 2 El i assen LA, fl ugoson A K u ro l J , and Siwe H: Th e effects of orthodontic Ire'dtmen t o n periodontal

t issues i n patients with red u ced periodontal suppo rt , Eur J Orthod 4: 1-9 1982

13 Page R: Frontiers i n periodo n tics Summary by Nic h ols O Pacifie Coast Society o f Orthodon t ists

B ulletin Spring 39- 4 1, 1991

14 K essle r M: I nterrela t ionshi ps betwee n o rt hodon t ics and periodonti cs Am J Ort h od 70: 154- 172 19 7 6

I S M elsen B : Adu l t ort h odontics , J a in Ort hod 22:630-641, 1 988

1 6 !-I OSI E Zachrisson B Y and Ba l d a u f A: Orthod o nti cs and Pl'riod o nli cs C h icago: Qu i ntessence Pu bl i ing , 1 985

sh-,

o.aptcr 7 OraillY81('ne CQlIsi(/,'r(Jf itms • 33

1 7 Goldberg D, and Turley PK: Onhodonlic space closure of the edentulous maxillary first molar area in

adu lt s Int erna t iona l Journ al of Adult Ort h odontic and Orthogn.l1hic Surgery 4:255 -266 1989

18 Stepovic h M L: A clinica l st ud y o n closing edentu l ous spaces in the mandible Angle Orthod 49

:227-233.1979

19 M ostafa YA , Tawfik KM , and EI-Mangoury N H : Surgical orthodontic treatment f or overcruptoo

max ill ary mo l ars.} Q in Or1hod 1 9:350-35 1 1 985

20 SJx'rTY T P : The role of too t h ext ru sion in treat m en t plann ing for on hogna t hic s urgery I nternati ona l

J ournal o f Adu l t O rt hodon t ic and Onhogna th ie Surgery 4 : 197 -2 11, 1988

21 Artun }, Kokich VG, and Osterberg SK : Long-term effect of root proximity on periodontal health after

orthodontic treatment Am J Onhod Oentofacial Orthop 91: 125 - 130, 198 7

22 Viazis AD Cori naldesi G, and Abrolmson MM : Gingiva l recess i on and feneStrJtion in orthodontic

treatment.} C l in Orthod 25:633 - 636, 1990

ell

For years covering exposed roots with soft-tissue grafting has been the ultimate goal in

periodontal mucogingivai surgery Today that goal has been largely met with the usc

of various techniques I _ of The larger arena of esthetic enhancement now dominates our

thought processes in dentistry Periodontal plastic surgery is the term used to describe

surgical procedures performed to correct or eliminate anatomic, developmental, or traumatic deformities of the gingiva and alveolar mucosa, I These procedures would also include treatment of marginal tissue recession, excessive gingival margins and

localized alveolar ridge deficiency, and exposure of unerupted teeth for orthodontic treatment.)

Excessive gingival display is a condition resulting from exccssive exposure of maxil

-lary gingiva during smiling, commonly called gummy smile or high lip line.) This

condition may be caused by a skeletal defonnity, a soft-tissue deformity, or a combination of the two Another cause is short clinical crowns due to incomplete cxposure

-of the anatomic crowns If short clinical crowns result in a gummy smile gingival

contouring may be accomplished to achieve the desired csthetic result

Periodontal plastic surgery may be used not only to enhance esthetics but also to aid in orthodontic treatment by a variety of means The gummy smile can be man-aged to create proper clinical crown length and achieve pleasing gingival contours Diagnosis of this problem can be made by the orthodontist early in treatment Evalu-ation of the smile line, lip line, and tooth length can help differentiate between excessive gingival display due to vertical maxillary excess (Fig AS.I) or insumcient

crown length (Figs AS.2 through AS.S) Furthermore, the establishment of the ginal tissue at the level of the ccmcnto-enamel junction ( eE J ) enhances esthetics and

mar-creates a situation in which the orthodontist can have a larger comfort zone when treating periodontally involved cases

In addition, successful root covcrage techniques can aid in the treatment of quate attached gingiva as well as root sensi ivity and unesthetic appearancc Root coverage techniques for treatment of cuspid marginal tissue recession in the past have been relatively unpredictable procedures Soft-tissue grafting was done primarily to increase the band on attached gingiva In 19S2, a predictable technique was described

inade-for covering Toots using the free gingival graft following citric acid root conditioning.l

In 1985, the subepithelial connective tissue graft for improved esthetics in root coverage grafting was introduced Since then, it has proved especially useful in the treat-

-ment of gingival recession (Figs A8.6 through AS.9)

36 • Part A i7(' hmi nurJ' £mm i na l O Il oj l hI.' PU lil'fll

AB , 2 Figure AB.2 Excessive gingival display due to in s uffi cie nt

Fl gc quw

"""'

InClS

fig u re AS 4 Anterior view: lower in c isor spacing and

figure A S e Soft-tissue recession in the maxillary ce ntral

Cha p te r 8 P{'riodonwl !,la s /ic Surgery 37

Figur e AS S The same pat i ent as in Figure A8.4 afte r pe ri

o-donta l plasti c s urgery

Figure A8 7 Th e same pati e nt a s in Figure A8 6 I month

in th e CEJ area or the cen t ral incisors