Dental Corner: "A foundation for treating canine periodontal disease" (October 2006). On page 648 of the section "Plaque preventive sealant and gel," the article erroneously states that no studies have been published to document the effectiveness of OraVet Plaque Prevention Gel Sealant (Merial). The effectiveness of this sealant was demonstrated in the following study: Gengler WR, Kunkle BN, Romano D, et al. Evaluation of a barrier dental sealant in dogs. J Vet Dent 2005;22:157-159. We regret this error.