Clinical evaluation of polyamide polymer burs for selective carious dentin removal

The aim of this study was to evaluate the carious dentin removal efficacy of new rotary polyamide burs capable of selectively removing infected dentin without removing sound dentin.

This study included 40 subjects with bilateral occlusal carious lesions on mandibular first permanent molars. The lesions were randomly assigned to receive one restoration after carious dentin removal with a polymer bur and the second after removal of carious dentin with a carbon steel round bur. Both procedures were completed by a single operator in one appointment. The efficacy of caries removal, time taken for caries removal, and patients' perception of the treatment were evaluated. The restorations were evaluated immediately and after six months using intraoral periapical radiographs (IOPA).

The results revealed statistically significant differences between the polymer burs and carbon steel burs with respect to caries removal efficacy (p<0.001) and the time taken for caries removal (p<0.001). No statistically significant results were obtained regarding patients' perception of the treatment and longevity of the restorations.

Carbon steel round burs remove caries lesions more efficiently than polymer burs but they tend to contribute to the over-preparation of the cavity. Polyamide burs were found to be self-limiting and lose their cutting efficiency on reaching affected dentin and do not cut sound dentin. The time required for caries removal using the polymer bur was significantly longer than when using a carbon steel round bur.

One of the goals of conservative dentistry is to develop a method for removing caries-infected dentin while preserving caries-unaffected dentin. The use of polymer burs appears to offer a straightforward and efficient means for achieving this goal and conserving healthy tooth structure.