assess the efficiency of dental plaque control in decay teeth, gingivitis prevention for the 12 years- old pupils at some schools in the suburb of hanoi

ABBREVIATION CPITN Community Periodental index of treatment needs CI-S Calculus index simplified DMFT Decay missing, filling teeth PDT Permanent decay teeth SS Secondary school R R

MINISTRY OF EDUCATION AND TRAINING MINISTRY OF HEALTH NATIONAL INSTITUTE OF HYGIENE AND EPIDEMIOLOGY

SUBURBS OF HANOI

Major: Epidemiology Code: 62 72 70 01

ABSTRACT OF DOCTOR OF MEDICINE THESIS

Hanoi - 2012

THE PROJECT WAS COMPLETED AT NATIONAL INSTITUTE OF

HYGIENE AND EPIDEMIOLOGY

Supervisor:

1 Associate professor Doctor Trinh Dinh Hai

2 Doctor Dao Thi Dung

At … o’clock, day …… month …… Year 2012

The thesis can be found at:

1 National library

2 Library of National Institute of Hygiene and Epodemiology

ABBREVIATION CPITN Community Periodental index of treatment needs

CI-S Calculus index simplified

DMFT Decay missing, filling teeth

PDT Permanent decay teeth

SS Secondary school

R Rate

G Gingivitis

ODH Oral and Dental Hygiene

WHO World Health Organization

INTRODUCTION

Decay teeth and gingivitis were two popular diseases among the oral and dental diseases in the world as well as in our country The diseases could be suffered very early as soon as teething (6 months of old) If the diseases were not treated timely, it could produce a side-effect in site or the whole body, affecting to the physical and aesthetic development of the child in the future

In 20 recent years, thanks to the remarkable progress of science technology, it was found that the reason and pathogeneswas of the oral and dental diseases was caused by the dental plaque Then the appropriate preventive methods was found; however, the preventive methods for the oral and dental diseases was very simple, not too difficult, did not require the expensive equipments, the high professional technicians and the low expenses, easy to implement in the community, in particular in the schools

In 2001, according to the investigation results on the oral and dental health national wide, there were 90% people suffered by the oral and dental diseases, whereas the operation of the oral and dental preventive network did not satisfy the requirements Therefore, at the present, the oral and dental prevention was the key mission of the Othodonto – Stomatology major

In Hanoi, the investigation results on the oral and dental health in

2007-2008 with the pupils of primary and secondary schools showed that the rate of oral and dental diseases were increased under the ages

To strengthen the school of dentistry program, as well as find out the new methods linking with the school of dentistry program aiming at raising the quality, effectiveness of oral and dental diseases prevention for the pupils, within the framework of the project “Assess the efficiency of school of dentistry activities in Hanoi in 2009-2010 of National Institute of

Othodonto – Stomatology”, we researched the theme: “Assess the

efficiency of dental plaque control in decay teeth, gingivitis prevention for the 12 years- old pupils at some schools in the suburb of Hanoi” to:

1 Describe the reality, some factors relating to the decay teeth, gingivitis, dental plaque and knowledge, attitude, practice about the oral and dental care for the 12 years-old pupils at some secondary schools in Gia Lam, Quoc Oai District, Hanoi City in 2009

2 Assess the efficiency of dental plaque control in the decay teeth, gingivitis prevention for the 12-year-old pupils at 04 secondary schools of two researched districts

NEW CONTRIBUTIONS OF THE THESIS

1 The thesis provided the valuable reference information for the specialized scientists about the oral and dental diseases, the oral and dental care knowledge, attitude, practice and the reality of oral and dental care at some secondary schools in the suburb of Hanoi

2 The research result presented the effective intervention model to control the dental plate, help the school medicine managers develop the effective preventive methods for the decay teeth, gingivitis in the community

STRUCTURE OF THE THESIS

The theswas had 125 pages; Introduction: 03 pages; Overview of document: 34 pages; Subject and research method: 26 pages; Research result: 34 pages; Discussion: 25 pages, Conclusion and Recommendation:

3 pages There were 44 tables, 6 figures, 1 diagram and 4 charts in the thesis Besides, there were 139 documents in the reference, of which there were 60 documents in Vietnamese and 79 documents in English; the appendix section had 22 pages

Chapter 1 OVERVIEW OF DOCUMENTS

The oral and dental diseases were the very popular diseases on the world as well as in Vietnam, of which the decay teeth and gingivitis were the most popular diseases Previously, the decay teeth and gingivitis were very popular in the developed countries due to the diet with much sugar and milk However, in the two recent decades, the reality of decay teeth in two groups of countries (developed and developing countries) was conversed The rate of decay teeth in the developing countries was increased due to lack of drinking water with fluoride, the diet with much sugar, and the unvalued dental education The developed countries considered the dental education as the national policy, fluoride the

drinking water, implemented the diet with less sugar, used the toothpaste with flour, filled the teeth slot so that the rate of decay teeth was significantly reduced

Previously, most of the countries in the world concentrated on the oral and dental diseases treatment, recovered the chewing function and aesthetic, so that it was very costly Today, thanks to the remarkable progress of the science technology, it was found that the reason and pathogenesis of the dental diseases were caused by the dental plaque, and then the preventive methods were very effective In some countries, the decay teeth, gingivitis was significantly reduced Therefore, WHO recommended that all the countries worldwide should prevent the oral and dental diseases early at the age of pupil, which was the most feasible strategy

Vietnam was the developing country, in the recent years, the socioeconomic situation has been developed, the nutrition had many changes such as using much sugar, milk, etc, whereas the community was not aware enough about the risks, evils as well as the preventive measures for the oral and dental diseases Many research works showed that in many local areas, the oral and dental diseases tended to be increased, while the operation of the oral and dental disease preventive network did not satisfy the requirements Therefore, at the present, the work of preventing the oral and dental diseases was the key mission of the othodonto – stomatology major

To solve this situation, in many previous years, the othodonto – stomatology major actively performed the mission of initial oral and dental health care, of which the key mission was the school of dentistry work with 04 contents: Educate dentistry for the pupils, use the gargle with 0,2% flour weekly in the school, fill the teeth slot, examine and treat early the oral and dental diseases in the school However, the implementation and effectiveness of this work were different under each group of ages, each period Partly, the reason was that the knowledge, attitude and practice of the pupils on the oral and dental care were various under each period, each place; so that the rate of oral and dental diseases for the pupils was still high The intervention researches showed that if the preventive measures for the oral and dental diseases were implemented well, the rate of oral and dental diseases would be significantly reduced It was very practical to strengthen the preventive measures for the oral and dental diseases, particularly for the ages of pupil and useful to save the national budget, reduce the burden for the Public Health Sector; reduce the costs for the society to improve the public health

On the national dentistry conference in 2010, according to the report

of National Institute of Othodonto – Stomatology, over 80% of people was suffered by the oral and dental diseases, with the high rate of the disease as today, if it only concentrated on the treatment and recovery without the preventive treatment, it couldnot finish the endless treatment needs for the community; the payable costs and budget were very big and it will lose much time of the patients and doctors However, at the present, the network of othodonto–stomatology surgeries was very little, the group of specialized doctors was not enough, the budget was narrowed Despite thanks to the socialization, a number of private hospitals, consulting-rooms were significantly increased (but only in the cities), which solved a part of treatment demand for the people; it still costs a lot of expenses, time of the individuals and society So that the prevention work of oral and dental diseases was very important and essential One of the important methods

in the oral and dental diseases prevention work was the Dental Plaque control method

The dental plaque or biofilm was one bacteria community living in the organized structures in the interface between a hard side and liquid existed in the teeth surface The bacteria in the dental plaque lived in each micro-cluster in one shape of extracellular polymer substances By using the PCR technology, it was found that there were 500 species of different bacteria in the dental plaque The dental plaque was considered as the most important exotic agent in the oral and dental diseases The dental plaque could make the damages because of the two impact mechanisms: Direct impact: Enamel made dental plaque become weak, disintegrate cell, peel

of many gummy tissues leading to gingivitis, prostaglandine destroyed alveolar bone Indirect impact: caused by bacteria and secretion of bacteria

as a antigen These antigens stimulus the immune reactions ion site as well

as the whole body Then, the intermediary products of the immune reactions destroy the organization of gums The capacity making the decay teeth of the dental plate was based on its adhesion into the teeth, the capacity making acid from C12 and C6 and pH of oral environment

Methods to control the dental plaque: Mechanic methods: brushing teeth, cleaning spaces between teeth, sprinkling method Chemical method: Use gargle for preventing and reducing the dental plaque with flour to reduce the decay teeth, etc Overcome and repair the errors: Position of teeth, adjacent joints, repair the wrong teeth function

Nutrition regime and preventive propaganda

Chapter 2

SUBJECT AND RESEARCH METHOD

2.1 Subject, place and time of research

2.1.1 Research subject

- 12 years-old pupils, regardless of gender, were willing to join in the

research, excluding the pupils who change the school

2.1.2 Research place, time:

- 6 secondary schools of Gia Lam and Quoc Oai Districts, Hanoi

- Research time: 5/2009 – 3/2011

2.2 Research method [32], [33], [34]

2.2.1 Research design

Cross-descriptive epidemiology methodology with analysis,

intervention epidemiology methodology with control

2.2.1.1 Cross- descriptive epidemiology methodology

Main purpose selection: + Quoc Oai District: Dong Quang, Thach Than

and Quoc Oai Town Secondary Schools

+ Gia Lam District: Co Bi Secondary School, Trau Quy Town and Da

Ton To assure the medical ethics, took all pupils of 06 schools with 1022

pupils, examined dental and oral; interviewed KAP about oral and dental

Among 6 secondary schools, we chose 04 schools and contigently

distributed into 2 groups, the intervention group with 2 schools, 306

puplis: Dong Quang- Quoc Oai District (156 pupils) and Trau Quy Town-

Gia Lam District (150 pupils), the comparison group with 02 schools, 303

pupils: Quoc Oai Town- Quoc Oai District (152 pupils) and Da Ton- Gia Lam District (151 pupils)

- Identified the reality of KAP of the pupils about oral and dental care

- Identified some factors relating to decay teeth , gingivitis

2.3.2 Assess the effectivess of dental plaque control in decay teeth, gingivitis prevention for the 12 year-old pupils in 04 secondary schools

of 2 researched districts

- Tested the dental plaque control intervention method for the research

subject: Cooperating 03 methods: dentistry education method, mechanic method: guide brushing with supervision under the innovated Bass method and chemical method (use gargle)

- Assessed the effectivess of dental plaque control by the oral and dental

diseases reality, by the PI debris indexes (using color indicator), CI-S index, DI-S, OHI-S and KAP about the oral and dental care of the pupils

2.4 Intervention assessement:

- Directly interviewed the pupils by questionaire

- Examined teeth of pupils (by bill of WHO) for assessement

- Assessed eefficiency index and intervention index:

Used efficiency index to assess some changed indexes (rate %) after intervention in comparison with before intervention:

Efficiency index (EI) (%) = / p1 – p2/ x 100

p1

+ p1 : Rate before intervention

+ p2 : Rate after intervention

Used intervention index (II) (rate %) to assess the intervention effect between the intervention group and the comparison group:

Intervention index (%) = Efficiency index (intervention group) – Efficiency index (comparison group)

Compared the result of the collected indexes before and after intervention and give the essential conclusions

Chapter 3 RESEARCH RESULTS

3.1 Reality of decay teeth, gingivitis, dental plaque, knowledge, attitude, practice about oral and dental care and some factors related

to oral and dental diseases for the pupils

3.1.1 Reality of decay teeth, gingivitis and dental plate for the pupils

3.1.1.1 Reality of decay teeth

Table 3.1 Permanent decay teeth rate of the pupils under district

- Rate of pupils who were permanent decay teethof both two districts was low 31.1%

3.1.1.2 Reality of gingivitis

Table 3.3 Number of pupils who were gingivitis under district

Gingivitis

Quoc Oai (n = 510)

Gia Lam (n = 512)

Total (n = 1022)

QT Rate

(%)

QT Rate (%) Qt Rate

(%) Non-gingivitis (CPITN=0) 295 57.8 318 62.1 613 60.0 Gingivitis (CPITN = 1;2) 215 42.2* 194 37.9** 409 40.0

p * - ** <0.05 (Quoc Oai and Gia Lam)

- Rate of gingivitis (CPITN=1.2) of the 12 years-old pupils in both two districts was medium 40.0%

3.1.1.3 Dental plaque reality of the pupils

Table 3.5 PI debris index reality of the pupils under district

Rate (%)

Total (n=1022) 49 4.8 79 7.7 793 77.6 101 9.9

p>0.05

- The dental debris rate for the pupils in two districts was at the different levels, ranked: Level 0, Level 1, Level 2, Level 3 The difference between the rates of dental debris reality did not mean statistic (p >0.05)

Table 3.9 Calculus reality of the pupils under district

Place

Quoc Oai (n=510) 81 15.9 247 48.4 143 28.0 39 7.7 Gia Lam (n=512) 112 21.9 330 64.5 58 11.3 12 2.3

3.1.2 Knowledge, attitude and practice about ODC of research pupils

3.1.2.1 Knowledge of Oral and Dental care

Table 3.15 the average mark of ODC knowledge of district’s pupils

Districts

Knowledge mark

Gia Lam (n=512) 108 21.1 122 23.8 282 55.1

Table 3.17 Pupil’s attitude of ODC (n = 1022)

It was needed to brush teeth after the main meals each day:

3.1.2.3 Practice about ODC

Table 3.18 Practice about ODC daily (n = 1022)

Method of oral and dental hygienve after the main meal

Number of teeth -brushing per day:

- After the main meal : 22.5%

- Number of teeth- brushing per day: 39.5%

Table 3.20 Time to brush and change the tooth brush (n = 1022)

Time to brush each time

- more than three minutes 309 30.2

Time to change tooth brush:

-The number of pupils who brushed their teeth under the regulated time (more than three minutes) only accounted for 30.2% and 32.5% was the scale to change their tooth brush timely ( three months one time)

Table 3.23 Oral and dental care after Eating, drinking sweet food and

beverage and beverages (n=1022)

Number of time of eating, drinking sweet food and beverage and

beverages each day:

Oral and dental hygience after eating, drinking sweet food and beverage and beverages

- 68.8% of pupils ate and drunk sweet food and beverage and beverages (biscuit, sweet, cream, pepsi, etc.) many times per day Only 4.1% of them

followed to brush their teeth after eating and drinking

Table 3.24 To take a latest visit to dentist for teeth examination

3.1.3 The relationship between ODH and DT and Gingivitis of pupils

Table 3.27 Relationship between ODH and PDT

- There was a close relationship between oral and dental hygiene and

Permanent DT with OR=2.8; P<0.05

Table 3.28 Relationship between ODH and Gingivitis

Good 118 11.5 331 32.4 p < 0.05

- There was a close relationship between ODH (good or not good) and O

(yes; no) with OR=2.9; p<0.05

3.2 Assess DP control efficiency in DT and G prevention to Pupils 3.2.1 DP control efficiency in the prevention of DT and G to Pupils

3.2.1.1 Dental plate control efficiency

Table 3.29 Plate Index (PI) in two group of pupils

% 36.9 87.7 36.7 34.0

PI > 2 QT 193 37 191 198 pp1-2<0.01

2-4 <0.01

80.8 77.1

% 63.1 12.3 63.3 66.0

- PI ≤ 2 after IV of IV group increased clearly in comparison with pre-IV

(EI =134,5%, p<0.01) In the comparison group, PI ≤ 2 decreased (II =

Level 1 QT 24 168 23 16 p1-2<0.01

p2-4 <0.01

600.0 630.4

pre-Table 3.31 Number of pupils with calculus