Sir, the habit of chewing areca nut with or without tobacco receives little attention, especially their toxic effect on hard tissues. People are switching over to smokeless tobacco and areca nut products due to the ban on smoking in public places.

The effects of areca nut chewing products on hard tissues are scanty or not available. We hypothesised that the hardness of areca nut and tobacco present in chewing products might have a role in the causation of dental attrition and sensitivity.

Thus we have randomly collected the data on attrition and sensitivity of the 169 subjects (123 chewers and 46 non-chewers) attending Government Dental College, Ahmedabad, India. The data was analysed using the Chi square test.

The result suggests that areca nut and tobacco chewing are having adverse effects on teeth as a significantly higher percentage of attrition was observed among chewers as compared to non-chewers.

Further analysis of data on the basis of different chewing habits indicated no significant difference in the number of attrition cases between maya (containing areca nut, lime and tobacco), gutkha (consisting of areca nut, catechu, lime, cardamom and unspecified flavouring agents) and mixed (gutkha, maya, pan, tobacco, arecanut) chewers.

Sensitivity towards cold beverages was also significantly higher among the chewers in comparison to non-chewers. Collaert and Fischer reported that local pulpal inflammation, traumatic oral hygiene and dietary habits have been considered in the etiology of dentine hypersensitivity1.

They also suggested that dentine hypersensitivity is probably caused by a change in fluid flow in the dentinal tubules, which in turn excited the nerve endings located at the pulpdentine border.

The higher sensitivity towards cold foodstuffs could be attributed to excessive load on mastication on the teeth due to the chewing of tobacco and areca nut. These chewing materials might have affected indirectly (excessive load of mastication of chewing material on teeth) the enamel layer covering the dentinal tubules and caused adverse effects on the tubules structure and function. The duration of habits did not show any definite trend, which indicates that some other natural factors such as ageing, structure of tooth etc. might also be responsible along with chewing habits for attrition and sensitivity.

Excessive abrasion of the incisal and occlusal surfaces of the maxillary and mandibular teeth might occur with the habitual use of coarse, abrasive chewing tobacco or cigars as suggested by Christen2. Bowles et al found insoluble particulate matter about 0.5% of the dry weight of average tobacco samples3.

The insoluble particulate matter of tobacco might be one of the underlying causes of higher attrition along with other factors such as the hardness of the areca nut, increased load of mastication on tooth due to chewing etc. The data suggest that areca nut and tobacco chewing are responsible for higher dental attrition and sensitivity. However, the data should be interpreted with caution for the general population as the subjects attended the hospital for some dental problem. Further, studies are in progress to substantiate these results. See Table 1

Table 1 Attrition and sensitivity among chewers and non-chewers. Figure in parenthesis is percentage; *P < 0.005
Full size table