Through current scientific evidence, the application of pit and fissure sealants in permanent dentition is a procedure consistently based on the prevention of caries, however, little evidence supports the performance of this technique in primary molars, and its application is reserved for high risk conditions. The objective of this systematic review was to answer the following question, formulated through the PICO strategy: Does the application of sealants contribute effectively to the prevention of caries in primary molars? Additionally, it was intended to understand the success rates inherent to the retention of sealants in this dentition. Bibliographic research of scientific articles published between 2005 and 2020 in the electronic databases PubMed, B-On, Cochrane Library and ScienceDirect, through research terms: pit and fissure sealants; primary teeth; primary molars; dental caries; prevention and retention, articulated through the boolean AND marker. Inclusion and exclusion criteria were established. For inclusion: clinical trials, randomized controlled trials, cohort and case-control studies, conducted in primary dentition and whose dental outcome was: the development of caries and/or, the rate of retention of pit and fissure sealants, comparing the intervention (sealant application) with the absence of application or with the implementation of other preventive measures. The methodological line followed for the selection of articles is presented in the PRISMA flow diagram. The methodological quality assessment of clinical trials was performed using a Cochrane tool and the Newcastle-Ottawa scale was used for the cohort study.
Regarding the efficacy of the application of sealants in the prevention of caries, three of the four studies included showed a positive association between the application of this technique and the lower incidence of caries. Although the studies of Joshi et al.; Hong et al. and Chadwick et al. share a similar methodology (application vs. non-application of sealant), in the latter, there was no significant association between the intervention and the outcome evaluated. Regarding the retention rate, it is verified that the authors consider, in a different way, different variables, namely, light curing cycles, acid conditioning techniques and different types of sealants, making it difficult to accurately evaluate them. However, it is verified that, overall, the application of this technique presents satisfactory retention rates in this dentition and can be applied effectively in primary molars. Given the effectiveness of the application of sealants in the prevention of caries in primary dentition, this measure should be included in a holistic preventive program, without being specifically reserved for children at high risk for this disease. Despite the anatomical characteristics less favorable to the retention of sealants, in this dentition, it is verified that due to their shorter period of permanence in the oral cavity, the retention rates are satisfactory. It is denoted, however, the need for future studies with stricter methodologies in order to obtain more robust results on this theme.
In conclusion, there is scientific evidence that demonstrates that the application of pit and fissure sealants in primary molars is an effective method to prevent dental caries.