Yes. Adults whose back teeth are free of decay and existing fillings are candidates for sealants, particularly those with deep occlusal grooves or a history of occlusal decay. There is no age limit for sealant placement — the clinical indication is an intact, at-risk tooth surface, not a specific age range. If you have never had sealants and your back teeth have remained cavity-free, sealing them now is a worthwhile preventive step.