Objectives: This study was designed to evaluate two factors possibly influencing incidence of gingival abrasion during toothbrushing: (1) the abrasiveness of a dentifrice and (2) the possible influence of feedback of oral sensory perception.
Material and methods: For this purpose, two separate, single blind, randomized clinical experiments were performed. The two groups of subjects were requested not to brush their teeth 48 h, prior to the experiments. After staining with disclosing solution gingival abrasion sites were recorded as small (< or =5 mm) and large (>5 mm), both before and after brushing. The dentifrice experiment was a split-mouth design, including 36 subjects, brushing their teeth in two randomly selected contra-lateral quadrants, either with or without dentifrice, whereas the remaining two quadrants were brushed, using the alternative choice. The sensory perception feedback experiment was a full-mouth design, including 43 subjects and two separate brushing exercises with use of dentifrice. The first brushing-exercise was performed by a dental hygienist, excluding the feedback of oral sensory perception of the brusher. After a 4 weeks period of familiarization to the manual toothbrush, subjects brushed themselves in the same random order as the hygienist, using a fresh brush, thus including oral sensory perception.
Results: In the dentifrice experiment, the increment of small abrasion sites was 5.86 for brushing with and 5.75 without dentifrice. There was no statistically significant difference between brushing with and without dentifrice. Both with and without dentifrice, more small abrasions were found vestibular, (3.78 and 4.22, respectively) as compared with lingual (2.22 and 1.42, respectively) (p=0.027, p<0.001). In the sensory perception feedback experiment, the increment in small gingival abrasion sites was larger for the subjects brushing themselves (8.86) as compared with the professional brushing (2.94, p <0.0001). Subjects caused more abrasion on the vestibular surfaces (6.28) as compared with the lingual (0.60, p=0.0001), where the professional did not show this difference (vestibular: 1.88, lingual: 1.30, p=0. 1388).
Conclusions: No statistically significant difference in the incidence of gingival abrasion was found between brushing with dentifrice or without dentifrice. Neither did oral sensory perception seem to affect the incidence of gingival abrasion.
(c) Blackwell Munksgaard, 2005.