The combined application of topical fluoride and fissure sealant--results after 2 years

Effectiveness of Sealants in Adolescents with High and Low Caries Experience

The aim of this 3-year longitudinal study was to analyze caries increment and the caries-preventive effect of sealants in adolescents in the setting of the German national health system. 434 pupils (193 male, 241 female) took part in compulsory school examinations at age 12 (mean 12.3 +/- 0.4 years) and 15 (mean 15.6 +/- 0.3 years) according to WHO criteria, including the examination of sealants. Mean DMFT increased from 1.78 (+/- 2.15) to 3.97 (+/- 3.68), mean DMFS from 2.79 (+/-4.07) to 6.94 DMFS (+/- 8.34), respectively. Logistic regression analysis showed that high caries incidence at the individual level was mostly associated with the type of school ('Gymnasium', RR = 0.3), gender (female, RR = 2.08) and high baseline DMFS (RR = 1.2 per surface), but not with the number of sealants. In an interaction model, adolescents with high baseline DMFS values had an even higher risk of caries increment with an increasing number of sealants compared to adolescents with fewer sealants (p = 0.047). At the tooth level, this effect was detected for first permanent molars, while sealants in premolars and second permanent molars did not result in a statistically significant caries-preventive effect due to the low caries incidence on these surfaces. Thus, sealants on occlusal surfaces of first permanent molars were only protective in individuals with low or moderate caries activity (p = 0.006), which indicates the need for other measures to reduce caries activity in high risk adolescents. In addition, rates of 19% lost sealants and 18% carious or filled surfaces in 3 years suggest a discrepancy between sealant retention under real-life conditions and the results of controlled clinical trials.

Evaluation of a school-based fluoride mouthrinsing and clinic-based sealant program on a non-fluoridated island

For many years the children of Guam have experienced a high prevalence of dental caries. Surveys conducted on the fluoride-deficient island found that caries levels were double those of US mainland children. In 1976 a school-based fluoride mouthrinse program was initiated involving over 22,000 children in grades kindergarten through eight in weekly rinses with 0.2% neutral NaF. A clinic-based dental pit and fissure sealant program was added in 1984 to the fluoride mouthrinse program. Over 15,000 children participated annually in the sealant program where more than 75,000 teeth were sealed the first year. After 8 yr of fluoride mouthrinsing (1976-1984) mean DMFS scores were 1.79 surfaces per child lower compared to baseline, a decrease of 0.22 DMFS per child per year. During this period proximal DMFS scores decreased 61%, buccal-lingual surfaces 31%, and occlusal surfaces 7%. After 2 yr of fluoride mouthrinsing and sealant application combined overall DMFS scores decreased an additional 2.34 surfaces per child, a reduction of 1.17 DMFS per child per year. Most of this decline took place on pit and fissure surfaces. For the 10-yr period a reduction of 4.13 DMFS per child was seen--a decline from 7.06 DMF at baseline to 2.93 DMF surfaces per child in 1986. This long-term evaluation indicates that dental sealants when used in combination with fluoride mouthrinse were particularly effective in lowering the prevalence of dental caries. Schoolchildren in participating grades on Guam now have dental caries rates close to those of US schoolchildren.

A laboratory and clinical evaluation of three dental luting cements

The loss of material from specimens of three luting cements was measured after continuous erosion cycling in the laboratory. The glass ionomer luting cement showed significantly less material loss than the zinc polycarboxylate and zinc phosphate luting cements. Two hundred and fifty restorations cemented with one of the three materials were studied clinically for marginal integrity and retention over 3.5 years. The data were tested using survival analysis. Zinc phosphate cement gave the best clinical performance. Possible explanations for the poor correlation between the findings in the laboratory and clinical study are discussed.