Method: DPBRN dentists enrolled 50 consecutive restorations placed on previously unrestored adult tooth surfaces, up to four per patient. The DPBRN comprises dental practices mainly from five regions: Alabama/Mississippi, Florida/Georgia, Minnesota, Permanente Dental Associates, and Scandinavia. Patient and restoration characteristics were collected during the visit. Dentist/practice information was obtained from previous surveys. Preoperative depths were diagnosed with methods routinely used in each practice for previously unrestored occlusal and/or proximal surfaces. Analysis of variance and logistic regression were done using generalized estimating equations to assess dentist/practice and patient predictors of enamel lesion restorations, accounting for clustering within practitioner and patient.
Results: 229 practitioner-investigators placed 5,532 restorations involving an occlusal surface and 4,166 involving a proximal surface in 4,397 patients; 1,447 included both occlusal and proximal surfaces (95% of eligible restorations were enrolled). About 13% of occlusal and 6% of proximal caries lesions were confined to the enamel based on preoperative assessment (p<.0001). DPBRN region, patient age, and patient sex (proximal only) were significantly associated with the percentage of enrolled enamel lesions (p-values <0.05). The percentage of enrolled lesions limited to enamel varied by DPBRN region from 20% to 3% for occlusal lesions, and 12% to 1% for proximal lesions. Dentists in the southeast US regions had the highest percentage of enamel lesions restored. Other patient and dentist/practice characteristics were not related to enamel lesion enrollment.
Conclusion: The significant differences in the percentage of enrolled enamel lesions between DPBRN regions, and lack of association with indicators of patient caries risk and other dentist/practice characteristics, suggest that the external environment (e.g., patient preferences, reimbursement model) has a substantial influence on dentists’ treatment decisions. Support: U01-DE-16746, U01-DE-16747.