Effect of brushing the teeth before and after meals on salivary pH: A quasi-experimental study

Aim: To determine the difference in salivary pH before brushing the teeth, and 5, 30, and 60 minutes after eating and after brushing the teeth. Materials and Methods: This is a quasi-experimental study. The subjects were selected randomly with purposive sampling technique. Forty-five individuals were divided into three groups of 15 each, at test periods of 5, 30, and 60 min. Subjects had fulfilled the inclusion and exclusion criteria. The most common food consumed by the subjects was rice. Subjects were given instructions on how to brush their teeth, and collect and store saliva, and were instructed to use a toothpaste containing 1.12% sodium monofluorophosphate. The study was conducted in the morning, and after all the saliva sample tubes were collected, the saliva tubes were stored at 4°C. Salivary pH was measured with a pH meter (Mettler Toledo, Greifensee, Switzerland) before eating; before brushing the teeth at 5, 30, and 60 min after eating; and immediately after brushing the teeth. Data were analyzed with one-way analysis of variance (ANOVA) and General Linear Model repeated measure ANOVA (P < .05). Results: The average salivary pH when brushing the teeth at 5, 30, and 60 min after meals was 7.32 ± 0.19, 7.40 ± 0.16, and 7.42 ± 0.13, respectively. Based on the research conducted, there was no significant difference in salivary pH after brushing the teeth at 5, 30, and 60 min after meals (P < .05). There were differences in pH between the time before and after eating and also after brushing the teeth in each group of 5, 30, and 60 min intervals (P < .05). Conclusion: Brushing the teeth does not need to be delayed between 30 and 60 min after eating as the salivary pH will return to normal shortly after brushing.