Effectiveness of oral health education on eight to ten year old school children in rural area of Magway Region, Myanmar

Background: Oral diseases are common and widespread around the world. Many oral health problems are preventable and early onset is reversible. Myanmar faces many challenges in rendering oral health services and about 70 percent of total population resides in rural areas. These relate to the availability and accessibility of oral health services. Therefore, oral health education is one key element to prevent oral diseases and to promote oral health. Methods: A quasi-experimental study was carried out at Basic Education Middle Schools in rural areas of Magway Township to study the effectiveness of oral health education on knowledge and behavior of eight to ten years old school children. A total of 220 school children, 110 from intervention school and 110 from control school, participated in this study from 2015 to 2017. Data for knowledge and behavior were collected before and after intervention in the two groups by using self-administered questionnaire. Tooth brushing method data were collected by direct observation with checklist. Oral health education was provided at eight weekly intervals for one year in the intervention group. After one year and six months, oral health knowledge and behavior were determined in the intervention group only to measure retention. Chi-square test, two samples t test, One way repeated measure ANOVA were used for data analysis. The study was approved by the Ethics Review Committee of University of Public Health in Yangon, Myanmar. Results: After education, a positive net effect of intervention and significant improvement was found in the intervention group compared to the control group regarding oral health knowledge (p<0.05) except one that is foods that can cause dental caries (p=0.107) and behavior (p<0.001). Retention of mean ± standard deviation on knowledge and behavioral scores were 2.45±1.12, 3.79±1.12, 4.07±0.98 and 1.56±0.90, 3.60±1.21, 3.24±1.31 at baseline, at one year after education and at six months after cessation of education

respectively, and, total knowledge and behavioral scores were significantly improved (p<0.001) among the school children in the intervention group.
Conclusion: The repeated oral health education was effective to promote and sustain oral health knowledge and behavior. Word counts: 342 Background One cannot be healthy without oral health. Oral health and general health should not be interpreted as independent entities. Oral diseases can affect the ability to work at home, at school or on the jobs [1]. Children with poor oral health tend to struggle in school, may lack self-esteem and may have less success later in life. Healthy baby teeth are extremely important for eating, smiling, talking and keeping the space for adult teeth [2]. Oral health status has a direct impact on general health and conversely, general health influences on oral health. Children who suffer from poor oral health are 12 times more likely to have restricted activity days than those who do not [3]. In the United States, more than 50 million school hours are lost annually because of oral health problems which affect children's performance at school [4].
Dental caries affects 60-90% of school age children and most of the adults. Periodontal disease is prevalent in 50-90% of adults, becoming severe in 10-15% of them, while gingival diseases occur in majority of children and adolescents of Kuwait [5]. Although dental caries is a prevent able disease, it is the most prevalent diseases in children of America [1]. In Myanmar, knowledge, attitude and practice pertaining to oral health among rural population were low [6] and oral health status among five year and twelve year old children were not satisfactory [7]. Dental public health care services are required more than before to reduce high level of dental caries in twelve to thirteen year age group in Myanmar [8]. Three month oral health education gave positive effect on total KAP scores and plaque scores of the study group aged twelve year old school children in Myanmar [9]. Myanmar populations have low opportunity to take sufficient oral health education because of inadequate dentist population ratio [10].
In order to assess the magnitude of the preventive task it is necessary to know the oral health situation of the school children. Myanmar faces many challenges in rendering health care services including oral health services and about 70 percent of total population resides in rural areas. These relate to the availability and accessibility of oral health services. Therefore, oral health education plays a pivotal role to solve the oral health problems, to prevent common oral diseases and to promote oral health of the rural population. Oral health promotion through schools is recommended by the World Health Organization for improving oral health and for prevention of dental diseases among school children. In Myanmar, oral health education programs are already existed and oral health services are provided to the school children yearly by a dental surgeon as part of functions of school health team but these oral health programs are not strengthened. The number of dentist is inadequate to provide dental services effectively to the school children and oral health education is believed to be an effective method for promoting oral health. The children aged eight to ten years among the school children are suitable for identifying oral health status and for providing primary prevention because of mixed dentition, both primary teeth and permanent teeth. Hence the current study was planned to obtain updated information on the oral health situation of the school children in

Data collection method
The research question was developed and reviewed by the experienced dental specialist.
The question consists of demographic characteristics, knowledge and behavior on oral health. Oral health education (OHE) was given to the intervention group only at eight weekly intervals for one year. An oral health education session for a period of about 45 minutes was prepared on key oral health messages such as structure and functions of teeth, types of dentitions, causes and prevention of common oral diseases, importance of brushing teeth twice daily, proper tooth brushing technique, importance of regular dental visit. Chalk and blackboard, dent form model, charts, toothbrush and toothpaste were used as oral health education aids. Proper tooth brushing technique (modified bass technique) was demonstrated on a dent form model. After completion of the whole study, an oral health education session was also conducted for the children in the control group.
A pilot survey was done on the 30 students to ensure the clarity of interpretation. A visit was paid to each school before data collection to discuss the research procedure with the school headmaster and written informed consent was obtained from the caregivers. At the beginning of the study, the baseline data were collected in both groups by using a selfadministered questionnaire except one behavioral question that is 'method of tooth

Data management and analysis
The data were checked for completeness and consistency daily and analyzed by using SPSS version 16.0. Descriptive statistics was computed for all variables. Differences between intervention and control groups responded to the knowledge and behavior questions by correct answers before and after intervention were calculated. The net effect of the intervention programme was estimated by subtracting the percentage change pre-to post-intervention in control students from that for the intervention students.  Table 2 shows correct knowledge and proper behavior on oral health among the school children between the two groups. In the intervention group, the correct proportion was higher in after intervention than in before regarding all knowledge questions and, in the control group, the correct response rate before and after intervention were nearly the same except main cause of tooth decay and gum diseases. In comparing the two groups before intervention, about 16% of intervention students and 12% of control students gave the true answer with regard to main cause of tooth decay. The majority of school children in both groups gave the true answer with regard to behavior about devices using in tooth brushing before as well as after intervention. Before intervention, about 7% of school children in intervention group and nearly 5% of school children in control group used dental floss to remove food debris stuck between the teeth. Regarding pattern of tooth brushing, nearly 5% in intervention group and only 3% in control group brushed their teeth according to the recommended method. Before intervention, no significant differences were found between the two groups in four out of five knowledge questions and in three out of five behavior questions (p>0.05). These were knowledge about the main cause of gum diseases and behavior about frequency and occasion of tooth brushing (p<0.05). After intervention, significant differences were found between the two groups in four out of five knowledge questions and in all behavior questions (p<0.05). The only one knowledge question shows no significant differences between the two groups was 'foods that can cause dental caries' (p>0.05). Table 3 shows percentage changes in response to knowledge and behavior on oral health before and after intervention between the two groups and a positive effect of oral health education for a period of 45 minutes at eight weekly intervals for one year was noted.

Discussion
At the beginning of the study, minimum age of the school children in both groups was eight year and maximum age was ten year. The duration of the study lasted for one and half year. There was no attrition in both groups after intervention. The correct response rates were more or less the same between the two groups before intervention in almost all of knowledge questions except one that is question concerning with main cause of gum diseases, in which correct answer rate of control students was significantly greater than that of intervention students. It may be possible that even in the absence of health education, some children might have tried to search and get correct answers and gain knowledge through various sources like social media, TV, toothpaste advertisements, etc.
After one-year-intervention, significant differences were observed between the two groups in almost all of knowledge questions except one that is question concerning with foods that can cause dental caries. This may be attributed to the school co-curriculum wherein some general information about unhealthy effect of sweetened foods and drinks on teeth is taught to the school children in the primary classes. No significant differences were found between the two groups before OHE in three out of five behavioral questions and with regard to frequency and occasion of tooth brushing, significantly more of the students in the intervention group brushed their teeth twice per day and also cleaned their teeth in the morning before breakfast and at night before going to bed compared with their control counterparts. This might be due to unequally in accessibility and availability of dental health services among the students. However, the proportion of correct behavior was significantly higher in all behavioral items for the intervention group following OHE. This may be because of methods applied and materials used in the OHE session. When the present study assessed the percentage changes in response to knowledge and behavior on oral health before and after intervention between the two groups, a positive net effect of intervention was observed. The improvement in overall knowledge and behavior was found in the intervention group as compared to the control group after OHE which may be ascribed to the mode of OHE. It was delivered to the students by means of an interactive talk around key oral health messages and the students who can give the correct answer were rewarded to participate actively and to get more interest in the OHE session. Well prepared and repeated OHE which would probably improve knowledge and enhance behavior. The OHE emphasized the importance of frequency, occasion and method of tooth brushing, use of tooth brush and tooth paste, and use of dental floss. A large teeth model was used to demonstrate the recommended method of tooth brushing to visualize all the students and after demonstration, some students were picked up in front of the class to show the method of tooth brushing step by step to know whether the students understand well. The finding of the present study was in accordance with an intervention study conducted in Ireland wherein an oral health intervention for six weeks was done amongst primary school children aged seven to twelve year and positive changes were observed in oral health knowledge and behaviors [11]. Other studies done in Chandigarh, Northern India [12], in Tanzania [13] and Greece [14] reported that school based OHE program was highly significant improved knowledge and behavior. In a study done in Kyauktan and Tharkayta Townships of Yangon Region in Myanmar, significant improvement of knowledge, attitude and practice scores on oral hygiene was found between the baseline and three months after intervention among 12 year old school children [9]. In India, a systematic review was conducted in a total number of 40 articles to assess the effectiveness of oral health education programs on knowledge, attitude, practice and oral health status. In their review, they reported that oral health education was effective in improving knowledge on oral health in all studies, however, with regard to practice outcome, thirteen studies were found to be effective and two studies were not effective [15]. These disparities might be due to differences in target age group, methods and duration of oral health education program and background characteristics of the study subjects. The present study showed that the eight weekly oral health educations for one year had a statistically significant effect on total knowledge and behavior scores of the oral health among the school children in the intervention group even though stopping of the education program for six months after one-year OHE and it was found that the students in the intervention group had sustainability on positive knowledge and behavior. In similar to the present study, a study done in India documented that reinforcement through repeated OHE sessions in the intervention schools resulted in significant improvement in oral health knowledge and practices even after cessation of the program [16]. Another study done in the northwest of England reported that schools with more frequent exposures to the program had better scores than schools with fewer exposures [17]. with the students and may be essential for the achievement of long-term benefits.

Conclusions
The repeated oral health education comprising of lecturing with interactive talk, demonstration and supervised tooth brushing method at eight weekly intervals for one year was found to be effective to promote and sustain correct knowledge and behavior among the school children.