Methods: School children aged 7-9 years in Shenzhen, China, were clinically examined. Permanent first molars with deep occlusal fissures or fissures with signs of early caries were selected and randomly allocated into one of the above four groups. Treatments were provided by local dentists in the schools. Follow-up examinations at 6-month intervals were conducted by two calibrated examiners using caries probes, disposable mouth-mirrors, and an intra-oral LED light source. Status of the molars and the sealants was recorded.
Results: A total of 422 molars in 161 children were treated at baseline, and 377 (89.3%) of them were examined after 24 months. No significant difference in effectiveness among the four preventive methods was found; 96.4% for FS, 92.7% for ART, 91.7% for NaF, and 95.9% for SDF (Chi-square test, p>0.05). Logistic regression analysis results show that fissure with signs of early caries at baseline had a higher chance to develop into a caries cavity after 24 months (odds ratio 7.47, p<0.001), irrespective of the preventive treatment received (p>0.05). The material cost per tooth for the treatments in the 24 months were US$0.3 for FS, US$1.0 for ART, US$0.5 for NaF and US$1.0 for SDF. Treatment times for the two sealants were similar, about 3-4 minutes per tooth, while that of topical fluoride application was much shorter, less than 30 seconds.
Conclusions: The 24-month effectiveness of the four methods in preventing fissure caries was similar but their material and time cost was different.
Funded by the University of Hong Kong (Ref: CRCG #200607176110).