Repetitive Coronal Polishing Yields Minimal Enamel Loss.
Purpose: The American Dental Hygienists’ Association recommends selective polishing because of risk of enamel removal and lack of documented therapeutic value. The initial study documenting enamel loss from polishing used methods not acceptable for clinical use, while results from other studies are inconsistent. This study examines the effect of simulated life-time polishing on enamel thickness. Enamel loss from polishing is compared to the enamel thickness just coronal to the cementoenamel junction (CEJ) to relate results to clinical application.
Methods: Eight premolars and 18 molars were polished 150 times with coarse prophy paste, then pre- and post-polishing micrometer measurements were compared. Eight unpolished premolars and 18 unpolished molars were used as control groups. Average enamel thickness from 10 premolars and 10 molars just coronal to the CEJ was chosen to represent minimal enamel thickness, and was calculated using digital radiography. T-tests were used to compare group means.
Results: The mean measurement difference was significantly higher for the premolar treatment group than the control group, but no difference was noted between molar treatment and control groups. Neither treatment group demonstrated significant abrasion when compared to average minimal enamel thickness. Root abrasion was noted on 5 molars.
Conclusion: The results of our study indicate that polishing may remove enamel, but the quantity removed is unlikely to be clinically relevant. Root surface abrasion seen on molars is disturbing, considering stain often occurs on exposed mandibular anterior root surfaces and may cause repeated and prolonged polishing. Further investigation into alternative stain removal methods is recommended.