Nghiên cứu điều trị tủy răng hàm lớn thứ nhất, thứ hai hàm trên bằng kĩ thuật thermafil có sử dụng phim cắt lớp vi tính chùm tia hình nón tt tiếng anh

108 INSTITUT E OF CLINICAL MEDICAL AND PHARMACEUTICAL SCIENCES --- TRAN THI LAN ANH RESEARCH ON ROOT CANAL TREATMENT OF FIRST AND SECOND MAXILLARY MOLARS BY THERMAFIL TECHNIQUE USING CO

108 INSTITUT E OF CLINICAL MEDICAL AND

PHARMACEUTICAL SCIENCES

-

TRAN THI LAN ANH

RESEARCH ON ROOT CANAL TREATMENT OF FIRST AND SECOND MAXILLARY MOLARS BY THERMAFIL TECHNIQUE USING CONE BEAM COMPUTED

108 Institute of Clinical Medical and Pharmace utical Scie nces

Name of supe rvisor:

1 Prof Trinh Dinh Hai, PhD

2 Assoc Prof Ta Anh Tuan, Ph.D,

Revie we r 1: Assoc Prof Truong Uyen Thai, PhD

Revie we r 2: Assoc Prof Dao Thi Dung, PhD

Revie we r 3: Assoc Prof Tong Minh Son, PhD

The thesis shall be defended in front of the Thesis Committee at 108 Institute of Clinical Medical and Pharmaceutical Sciences

At hour date month year 2020

The thesis can be found at:

1 The National Library

2 The Library of 108 Institute of Clinical Medical and Pharmaceutical Sciences

Q UESTIO N

The first and second maxillary molars havethe most complex root canal systemsin the arch Thecomprehensive investigat ion of the root canal system and three-dimensional obturating are important factors for successful treatment Cone Beam Computed T omography (CBCT ) which create 3-dimensional images of teeth and the surrounding structures has advantages, overcoming the disadvantages of the periapicalfilms, difficult to identify of canal system of molars with many root teeth as first, second maxillary teeth Thermafilobturation technique is ideally in the sealing with dense obturation, overcoming difficulties when obturation canals that are difficult to manipulat e with the pitch as in the first, second upper jaw group Combining advantages of CBCT film and Thermafil technique is guarantee for the success of the complex canal structures

of the first, second maxillary teeth to improve the quality of treatment and post-treatment evaluat ion marrow The effect of this combination has not been investigated in Vietnam Hence, we

conduct ed this study t itled "Research on the root canal tre atment

of the first and second m axillary molars by The rmafilte chnique uses Cone Beam Compute d Tomography”with the following

object ives:

1 Describe the morphological characteristics of the first and second

maxillary m olars root canal system based on Cone Beam Computed Tomography

2 Evaluation of the results of first and second maxillary m olars root canal treatm ent using Thermafil technique based on Cone Beam Computed Tomography

The urgency of the the sis:Saving a decaying tooth is

always a t op priority in our clinical practice For the first and second maxillary molars, the root canal system can be missed on the periapical film due to overlapping images Application of technological advances such as CBCT and Thermafilobturation technique improves t he quality of treatment and accurately evaluate the results of root canal treatment

Ne w contributions of the the sis: T he results of this study

showed the important of CBCT in diagnosis and determination of root canal system after root canal treatment Moreover, thermafilobturation technique has an excellent characteristic and obturates the canal and lateral and accessory canals when compare to other conventional techniques

The thesis has 122 pages including sections: problem statement (2 pages), overview (33 pages), subject s and Methodology (25 pages), results (20 pages), Comment (39 pages), conclusion (2 pages), recommendations (1 page) The thesis has 58 tables, 57 pictures, 111 references including Viet namese and English documents

Chapte r 1

O VERVIEW 1.1 Characte ristics of root canal system

1.1.2 Anatomical characte ristics of the first and second maxillary molars

1.1.2.1 First maxillary molars: Most First maxillary molars teeth

have three separate teeth The mesiobuccal root is the most complicated root on the arch, with a wide cross section in the

buccolingual dimension, or 2 root canal The distobuccal root and palatal root mainly has 1 canal

1.1.2.2 Se cond maxillary molars: Anatomical structure of second

maxillary molars is similar t o First maxillary molars but t he crowns are not square and big.Their roots are relatively close together or root fusion can be seen They generally are shorter than the roots of the first molar and not as curved Four canals are less likely

to be present in the second maxillary molar than in the first maxillary molars The ratio of Second mesiobuccal canal is not as high as First maxillary molars

1.2 Pulpal disease

1.2.1 Diagnosis of pulpal disease: The diagnosis is based on all

necessary information including medical and dental history, funct ional and physical symptoms, X-ray, assessment of periodontal status and clinical examination.According to the American Associat ion of Endodontic (2008), the terms that diagnose pulpal disease in clinical include: Reversible Pulpitis (acute, chronic), irreversible Pulpitis (acute, chronic), Pulp Necrosis (no infection, infection), Previously Treated, Previously Initiated T herapy Clinical terms for Periapical disease diagnosis: Symptomatic Apical Periodontitis, Asymptomatic Apical Periodontitis, Acute Apical Abscess, Chronic Apical Abscess

1.2.2 Root canal tre atment

1.2.2.1 Determine and maintain working length, working width during cleaning, shaping and obturatingroot canal systems

Working length: According to Johnson W et al., There are more than

50% of root canals without apical constriction, especially with apical

disease, so t hat there is uniformity in the treatment limit of the apical foramen, terminatingthe preparation is usually chosen t o be 0.5 to 1

mm short of the radiographic apex

Working width - size and root canal taper at the end of the cleaning

and shapingroot canal: due to t he initial size of the root canal, the cleaning and shaping and obturating technique root canal system

1.2.2.2 Cleaning and shaping root canal system

Cleaning root canal system: the common option is a combination of

sodium hypochlorite and ethylene diamine tetra acetic acid (EDT A)

To clean the complete root canal system, especially at the apical third of the root canal, the lateral and auxiliary canal, or the C- shaped canal, endodontic ultrasound systems are used widely Calcium hydroxide is widely used place in root canal between appointments due to its ability to dissolve organic tissue, kill bacteria, detoxify and act as a slow-release substance due to its low solubility in water

Shaping root canal system : the most popular shaping method today is

the use of a rotating NiT ifile

1.2.2.3 Obturatingroot canal system: The obturation is aim to seal

the entire root canal system in three dimensional to prevent the invasion of microorganisms from t he mouth or the area around the teeth into the root canal system

Thermafil technique: A technique developed by Johnson W.B

Thermafil was commercialized in the early 1990s, with Gutt aPercha (GP) α phase covering hard plastic core but still ensuring flexibility

Α phase GP is warmed by a oven, put into root canal with the core in the center to help compress the soft GP flowing into the root

canalsystem Gencoglu N et al assessed that the number of lat eral root canal found that more lateral canal sealed with T hermafil, followed by System B / Obtura, Horizontal, Microseal, Quick-Fill, Soft core Samadi F et al (2014) found that root canal Thermafil technique produces a higher percentage of GP in root canal, creating

a more homogeneous obturat ing block than warm GP compacting or cold GP horizontal compaction at apical third of root s According to Zogheib C et al., Thermafil technique give adequate obturationwithoutvoids and gaps in the obturatedroot canals

1.2.3 Assess the re sults of root canal treatment

1.2.3.1 Asse ssment of root canal obturating quality: In addition to

clinical evaluat ion, the most necessary factor is to evaluate t he root canal obturating results in terms of length, shape and density Root canal obturating must seal into the root canal walls, the obturatingmaterial must be tightly compressed, closed and sealed in the shape of root canals into a homogeneous GP block

1.2.3.2 Follow u p afte r tre atment: to maintain healthy or monitor

wound healing of apical area Success aft er t he root canal treatment

is that there are no clinical and radiographs signs of periapical lesions

1.3 Den tal radiography

1.3.1 PeriapicalRadiographs:The film is the most popular filmin

the dental treatment and a useful t ool to make a diagnosis, planning, and evaluate the outcome following endodontic treatment it has low cost; low radiation compares to the other x-ray techniques However, it can cause distortion, overlap and miss images The images can only be seen in the mesial and distal direction

1.3.2 Cone Beam Computed Tomography (CBCT):The significant

of advanced diagnosis tool such as CBCT over the traditional methods has been proven T his advance technique assists dental practitioner to identify root morphology, number of canals and other factors which can affect the final outcome of the treatment

Images can be displayed and investigat ed in the three orthogonal planes, axial, sagittal, and coronal simultaneously In CBCT film, sagittal, and coronal slices are made all along the length of the root, axialslices are perpendicular to the axis of the root with the thickness

of the slice usually 1mm The axial section shows the shape, the number of the root, the root canal, which is the most advantage of CBCT compared to periapical films Coronal slices shows the root canal morphology, the root canal curvature in the bucal - langualdirection Sagitalslices shows root canal images in mesial - distal direction.In the root canal treatment, the use of small field CBCT images to show a few teeth and the surrounding structure is suitable for minimizing radiation dose while good image quality, specific distinction structures such as enamel, dentin, root cavity, alveolar bone and cortical bone, tooth anatomical structure, root canal system characteristics, pathological image of root, etc According to Zheng et al, Zhang R and cs, CBCT effect ive in studying the external and internal morphology of the teeth, helping to optimize the results of root canal treatment A study by Abubara et al (2012) showed that CBCT determined the Second mesiobuccal canal number compared to the periapical film, clearly showing that untreated root canals.Research by many authors such as Yoshioka T

et al., Anita A et al., Estrela et al., Venskutonis T et al., showed

that CBCT film was more sensitive, identifying lesions accurately than the periapical film, the difference is more pronounced in the molars According to Estrela et al, CBCT film accurately assesses the curvature of the canals, helping to minimize errors and fractures during pulp treatment

Chapte r 2 SUBJEC TS AND METHO DS 2.1 Study subje cts : First and second maxillary molars are indicat ed

for root canal treatment of patients at the Hitech Department, Nat ional Hospital of Odonto-Stomatology of Hanoi, during 2016-

2019, teeth were eligible to be selected for research samples and patients voluntarily participated

2.1.1 Inclusion criteria: The patients is 18-60 years old and hasFirst

and second maxillary molars are indicated for non-surgical root canal treatment T eeth are diagnosed in 1 of the following diseases: Irreversible pulpitis, Pulp necrosis, Acute apical periodontitis, Chronic apical periodontitis

2.1.2 Exclusion criteria: The patients has systemic diseases

Patients cannot cooperate when performing treatment techniques and x-rays imat ure, periodontitis, internal and external teeth

p: success rat e aft er treatment, estimated at 90% (according to

research results of Peng L et al (2002)

a: t he level of st atistical significance, a here is det ermined to be 0.05

with 95% confidence level a = 0.05 → /= 1,962

d: is t he desired accuracy, taking d = 8%

From the above formula, we calculate the sample size as follows:

2.5.1 Record information before treatment: Administrative

information: age, gender, Symptoms of function, entity, pulp tests,

X-ray examination, diagnosis according to medical record

2.5.2 Investigation of root canal characteristics of teeth on

periapical film: The digital periapical film was taken with Yoshida

machine (Japan) Survey the number of roots, the number of root

canals, determining whether or not there is any periapical damage

2.5.3 Investigation of root canal characteristics of pre-treated teeth

on CBCT: CBCT taken with PlanmecaProMax 3D system (Finland),

endodontic mode, parameters: 5mA / 96kV / 12s / Ø 5,7x5,7cm /

200µm The data is exported into the DICOM file format (Digital

Imaging and Communications in Medicine) Analyze image on

computer with PlanmecaRomexis software (Finland) in 3 planes:

axial, coronal, sagital plane.Each film is read 2 times at intervals of 1

week, using a magnifying glass

2.5.3.1 Investigation of root num ber, root canal number,

appearance of Second m esiobuccal canal

2.5.3.2 Measure the distance between the orifices of canals

2.5.3.3 Noting the phenomenon of Fused Root teeth

2.5.3.4 Investigation of root canal morphologyof m esiobuccal root 2.5.3.5 Root canal curvature m easurem ent

2.5.3.6 Evaluation of periapicallesions on CBCT Record periapical

lesions in each root Use the length measurement tool to measure the optical circumference around the apex in the axial, coronal, sagital plane if available, choosing the largest size

2.5.3.7 Evaluate correlation of root and maxillary sinus floor: 2.5.3.8 Evaluation of maxillary sinus m ucosa thicknessbefore and after treatm ent:

2.5.4 Root canal treatment

2.5.4.1 Cleaning, shaping root canal system: Shaping root canal

system by Crown-Down technique with Ni-T i Protaper rotating files

2.5.4.2 Obturating root canal system : Dry the canal Apply AH Plus

at coronal third wall Warm the T hermafil, insert it to the working length Vert ical compress t he GP around the plastic core Additional

GP if needed Wait for GP t o stabilize, cut the shaft of Thermafil at the canal orifice T emporary cavity obturating with Caviton T ake CBCT film to check after obturating

Figure 2.21 Root canalfilling results on coronal slices of mesiobuccal root of First

maxillary molars

Figure 2.22 Root canal filling results on coronal slices of mesiobuccal root of second maxillary molars

Figure 2.23 Root canal filling results on axial slices

2.5.5 Clinical assessment 1 week after treatment

2.5.6 Evaluate the results of treatment after 6 months, 1 year, 2 years: clinical andCBCT examination

T able 2.11 Criteria for evaluating root canal treatment results after 6 months, 1 year, 2 years

Evaluation Criteria for evaluation

Success Painless, swollen and other symptoms, do not lose function,

X-ray has no bone loss, normal periodontal ligament

Failure T eeth have signs and symptoms of infection.And / or a new

X-ray lesion, increase the size of existing X-ray lesions Doubts There are no clinical symptoms but X-ray has periapical

lesions: new or constant size or only reduced size

2.7 Data processing: Stat a 14.0 software of WHO

2.8 Error control: Standardize treatment techniques, surveys, and

assessments T he process of inputting data into the machine is checked and reconciled 2 times

2.9 Ethics in research: T he study is conduct ed after the scientific

council of the 108 Clinical Medical Sciences Research Institute adopts the outline, following the ethical principles of human research

Chapte r 3 RESULTS 3.1 General characte ristics of the sample

Table 3.1 Distribution of patients by age and gender

3.2 Morphological characteristics of the root and root canal system of First and second maxillary molars on CBC T

Table 3.3 Root Number of First and second maxillary molars(M.M.)