The effect of chewing apples on dental plaque and food debris.

The aim of the present study was to assess the eleansing effect of the chewing of apples. The plaque situation in 47 children 12 years of age was assessed by tlie Plaque Index System. Judging from plaque incidence values, the chewing of apples had no cleansing effect on moderate amounts of plaque. A similar experiment with 57 children of the same age showed, however, that food debris was removed by chewing apples. (Received for publication 25 February, accepted 10 May 1974) The chewing of hard fruits and vegetables has been assumed to cleanse the teeth. Judging from experimental studies in adults, however, the chewing of fibrous food seems neither to affect the amount of dental plaque formed within 18 days''nor the gingivitis which develops in the abscence of active oral hygiene". Regular chewing of apples, on the other hand, has been found to reduce gingival disease in children, but deposits at the gingival margin were not assessed''. Since there is a causal relationship between plaque and gingivitis," the apparent discrepancy between the findings in adults and children may be related to the amount of plaque at the gingival margin. Plaque and gitigivitis have been recorded frequently in Norwegian children^''''"'•'•. The present study was conducted to assess a possible cleansing effect of apple chewing on the amount of plaque in children. Furthermore, the effect of this procedure on the oral clearance of food particles was evaluated. MATERIAL AND METHODS The material comprised 12-year-old children attending primary schools in Porsgrunn, Norway. Children with orthodontic appliances were excluded. Effect on plaque. The plaque situation of 47 children was assessed by the Plaque Index System. The maxillary and mandibular first molars and the incisors were recorded, i.e. 48 recordings in each child. One day after this initial plaque scoring, 24 children (the apple group, chosen at random among the participants) were asked to eat a whole unpeeled apple and then to rinse the mouth with tap water. Immediately after this procedure, the plaque situation was re-scored. Twenty-three children (the control group) only rinsed with tap water before the re-examination. The children performed their conventional oral hygiene between the recordings. The percentage frequency of the Score 2 is 100/48 of the nominal values. The frequencies of the Score 2 also express the plaque situation in children'. The incidence of plaque was assessed for each individual by paired comparison of the frequencies of the Score 2 from the two examinations. A possible effect of chewing apples on the amount of plaque was indicated by alteration in the incidence values. Comparisons within and bet\veen groups were evaluated by t-tests, a = 0.01. Effect on food debris. Twenty-seven children (chosen at random) were asked to eat a bun and then an apple (the apple group) while 30 children received only tlie bun. In order to detect food particles easily, the buns contained nycockin (Color Index No. 16255). Within 5 minutes after the eating of the red bun, the number of surfaces with food particles was recorded. RESULTS AND DISCUSSION Effect on dental plaque. The mean initial frequencies of the plaque Score 2 were 51 % and 52 % of the total number of the plaque scores (Table 1). No areas were assigned Score 3. Judged by the initial frequencies of the Score 2, there was no significant difference in amount of plaque between the groups (t = 0.52, d. f. = 45). The same frequencies of 162 BiRKELAND AND JORKJEND Table 1. Percentage frequencies (mean ± s.d.) of Plaque Index Scores 0 and 2 at the initial recording of 12-year-old children (48 PI I scores per child)