Effectiveness of MySmile App for Improving the Oral Health of Secondary School Children:

The mean decrement in plaque score will be assessed using the Plaque Control Record developed by O'Leary Drake and Naylor in 1972

The mean decrement in plaque score from baseline to follow-up between the intervention and control group will be assessed. For this test, the plaque is disclosed using a two-tone disclosing agent. The great advantage of the two-tone effect is that it can differentiate a new and matured plaque. The presence (+) or absence (-) of plaque is recorded in a chart, and the plaque incidence in the oral cavity will be expressed as a percentage (%). To determine the plaque index of an individual, the total number of surfaces with plaque will be divided into the number of available surfaces times by 100. The mean decrement score is obtained by subtracting the mean score at follow-up from the mean score at baseline. Finally, the mean decrement scores of the intervention and control groups are compared.

The mean increment in gingival health will be assessed using Gingival Index developed by Silness and Loe in 1963

For the selection of tooth, six (6) index teeth will be used. Each tooth will be assessed by scoring 0 = normal gingiva, 1 = Mild inflammation- a slight change in colour and slight oedema. No bleeding on probing, 2 = Moderate inflammation. Redness, oedema and glazing. Bleeding on probing, 3 = Severe inflammation, marked redness and ulceration and tendency toward spontaneous bleeding. To calculate the index tooth score, the score for each four (4) scoring unit is summed up and divided into 4. To calculate the Gingival Index for the entire assessment, sum up the scores for all index teeth and then divide by six (total index teeth). This will provide an overall index score for the patient's gingival health. The mean increment score is obtained by subtracting the mean score at follow-up from the mean score at baseline. Finally, the mean increment scores of the intervention and control groups are compared.

The mean increment of oral health knowledge, attitude and practice using validated questionnaires.

It consists of 3 domains; (a)The Oral Health Knowledge domain(16 items). Each item is assessed by 1 correct answer from 3 options. Total score = sum scores of correct answers with a score range from 0-16; (b) Oral Health Attitude domain will have 4 subdomains (21 items). Each item is assessed using a 4-point Likert scale (strongly disagree to strongly agree). Total score = sum scores of all items with a score range from 0-21; (c) For the Oral Health Behaviour domain (8 items). Answers are analysed accordingly into 'good' and "less good' OHB. Next, a score of 1 will be given for an item with 'good' behaviour and a score of 0 for an item with "less good' behaviour. The percentage score for Oral Health Behaviour will be calculated by adding all the items, dividing by 8, and times 100. Mean increment scores of 3 domains are calculated by subtracting the respective scores at baseline from follow-up scores. The mean scores were compared between the intervention and control groups.