Design, Development and Assessment of Dental Sealants with Anti-caries Functionalities Using Bimodal Agents

Abstract

Dental caries presents a high prevalence worldwide despite the availability of various prophylactic means, including the daily use of fluoride toothpaste, water fluoridation, dental sealants, oral health educational programs, and various mouth-rinses. Dental sealants were introduced to prevent dental caries in the pits and fissures of the occlusal surfaces. Sealants act as a physical barrier to prevent food accumulation in the pits and fissures. The current evidence suggests that sealing the occlusal surfaces of permanent molars in children and adolescents reduces caries up to 24 months when compared to no sealant. However, epidemiologic findings have shown an increase in sealant failures with increasing caries risk status due to biofilm accumulation at the sealant-tooth interface with further caries development. Thus, there is a need to develop new approaches to improve oral health care and decrease dental caries through the suppression of cariogenic biofilm formation in the sealant-tooth interface and dental materials surfaces. We proposed the development of novel dental resin-based sealant formulations with anti-caries functionalities intended to prevent caries development or progression. The sealing formulations contain two biointeractive agents; nano amorphous calcium phosphate (NACP) dimethylaminohexadecyl methacrylate (DMAHDM), a promising antibacterial monomer. The role of NACP content as a source of localized calcium and phosphate ions release delivered from a dental material for sealant applications and its combined use with the antibacterial monomer, DMAHDM, to impair anti-biofilm function were investigated. We comprehensively assessed the newly-designed formulations using in vitro biofilm models and analytical testing to investigate the potential biological effects of these novel materials on human enamel repair. We found that the formulation containing 20% NACP and 5% DMAHDM greatly reduced and modulated the cariogenic biofilm with effects on the virulence factors of key microorganisms. The combinatory formulation also presented a robust release of calcium and phosphate ions that imparted changes in the mineral loss of enamel. The formulation of a dental sealant with antibacterial and remineralizing potentials is a promising approach to prevent dental caries on the occlusal surfaces of children’s and adolescents’ teeth.