A new systematic review has found pit-and-fissure sealants to be effective regardless of tooth type or location. In fact, sealants on premolars may last longer and prevent more caries than those on first and second molars.
The authors decided to research the effectiveness of sealants after the ADA and American Academy of Pediatric Dentistry (AAPD) recommended pit-and-fissure sealants for primary and permanent molars in children and adolescents. Their results support the new sealant guidelines but also suggest that premolars can be effectively sealed as well.
"Based on the results of this comprehensive systematic review of randomized clinical trials, the performance of pit-and-fissure sealants ... do not seem to be negatively affected by mouth side, jaw, or tooth type," wrote the authors, led by Spyridon Papageorgiou, DDS, Dr med dent (Journal of Dentistry, November 2017, Vol. 66, pp. 8-17). "From the perspective of the sealant's clinical performance, all deciduous or permanent posterior teeth could be effectively sealed."
Dr. Papageorgiou is the attending dental physician at the University of ZĂĽrich Center of Dental Medicine in Switzerland. His fellow co-authors are from the Aristotle University of Thessaloniki in Greece and the Medical University of Vienna in Austria.
All posterior teeth can be sealed
Almost all adults in the U.S. eventually develop caries, which is a sobering statistic, and one that the profession is trying to curtail through prevention efforts, including placing sealants on the occlusal surfaces of children's and adolescent's teeth. Sealants have proved to be effective at preventing and arresting carious lesions, which is why the ADA and AAPD created the guidelines in 2016.
However, the guidelines don't mention premolars or distinguish between first and second molars. The researchers were, therefore, curious if the location of a pit-and-fissure sealant affected the sealant's longevity and ultimate caries prevention, as well as if premolars also could be effectively sealed.
To find out, they conducted their own systematic review by searching the scientific literature for randomized clinical trials related to pit-and-fissure sealants. They ended up with 16 trials with a combined total of 2,778 patients from 12 countries. The average patient age was 8 years old, and the sealants were applied to a mix of caries-free teeth and teeth with noncavitated carious lesions.
Overwhelmingly, tooth location did not have an effect on sealant performance. In terms of longevity and preventing caries, the researchers found no significant differences between sealants placed in the upper and lower teeth, right or left side of the mouth, or between first and second molars.
However, sealants placed on premolars developed fewer cavitated lesions and lasted longer than those placed on first permanent molars. While the difference was significant from a scientific standpoint, the researchers noted that it is still relatively small and the follow-up period was short.
"It is important here to stress out that the observed difference in caries incidence of sealed teeth does not lie solely with the significant better retention of the premolar sealant, but also to the inherent lower overall caries incidence of premolars compared to molars, even when left untreated," the authors wrote.
In addition, premolars have a different structure than molars and are exposed to less occlusal forces, which also may affect the statistic, they noted.
Support for the ADA/AAPD guidelines
The biggest strength of this systematic review was that it included thousands of patients from all over the world, and the results can be generalized to the average patient, according to the authors. However, because their review only included 12 trials, they were not able to analyze bias or heterogeneity as well as they would have liked.
These shortcomings suggest a need for future studies that take into account sealant longevity and caries prevention over a longer period of time, particularly for premolar sealants. Nevertheless, the authors noted that the ADA/AAPD sealant guidelines seem well-founded based on their findings.
"Results of the present meta-analysis seem to support the recent guideline of the American Dental Association suggesting the sealing of both primary and permanent molars, as no significant difference in sealant performance between primary and permanent molars was seen," they wrote.