RESUMO
The aim of this study, performed in Bangkok, was to evaluate the possibility of reducing fissure caries development using an antimicrobial varnish, Cervitec. Children aged 7-8 years and 12-13 years, 251 in each age group, with at least 2 sound contra-lateral permanent molars, were selected. A split mouth method was used with one test and one control tooth within the same jaw. At baseline and after two years all children were investigated for DMFS and DMFT. In addition, the size of any cavities was estimated. From 200 children, plaque samples of test and control occlusal surfaces were collected at baseline and after one year and processed to estimate the number of mutans streptococci. Mutans streptococci in saliva were estimated by the Strip mutans method. Cervitec varnish, containing 1 per cent chlorhexidine and thymol was applied at baseline, after 3-4 and after 8-9 months. The results showed that: Cervitec varnish reduced fissure caries development significantly; the levels of salivary mutans streptococci at baseline were significantly correlated with caries status at baseline and with total caries increment over the two-year period; caries development in a fissure was significantly correlated to the level of plaque mutans streptococci at that same site; three months after the last varnish application, a certain reduction of mutans streptococci in plaque could be seen in the test teeth; comparing the size of the lesions, more large cavities were found in the untreated teeth. It is concluded that varnishes should be considered as further options for prevention of fissure caries, possibly in more individualised programmes or in combination with already established methods.
