Relationship between Polishing Techniques and Bacterial Count on Different Denture Base Materials

Introduction: Wearing of dentures cause alteration in the oral microflora and increasing in number of bacteria and candida. The polished and fitting surfaces of the denture are both affected. Different polishing techniques influence the total count of bacterial accumulation on the denture surface. Aim: To count the bacterial colonies after polishing three denture base materials before and after six months of denture wearing by different polishing techniques. Materials and Method: Eighteen patients were randomly selected for construction of maxillary partial denture. They were divided into 3 groups: Group 1: Patients received conventional heat-cured PMMA (Acrostone) denture. Group 2: Patients received thermoformed polyamide (NEWULTRA) denture. Group 3: Patients received thermoformed acetal (Bio Dentaplast) denture. In each group, three patients had their dentures polished by pre polishing with brown rubber disc and fine pumice with wet rag wheel, and the other three patients with the same technique but followed by tripoli compound with dry rag wheel. Evaluation of bacterial counting was conducted before denture wearing and after six months of denture wearing. Swabs were taken from the palate of the patients and bacteria were counted. Findings: No significant difference was found between technique no. I and no. II in decreasing the bacterial count between the tested materials. Thermoformed polyamide showed the highest bacterial count after six months of wearing denture polished by technique no. II followed by thermoformed acetal and heat-cured PMMA. Conclusion: The second polishing technique produced less surface roughness and bacterial colonization on the tested materials than the first one.