RESUMO
Objective @# To evaluate the effects of root calculus residue and root cement preservation by ultrasonic subgingival scaling and root planing (SRP) with or without perioscopy.@*Methods @# Twelve teeth extracted due to severe periodontitis were randomly divided into three groups with four teeth in each group: ① Endoscope-assisted SRP group. The root surfaces of the affected teeth were cleaned with an EMS ultrasonic treatment instrument. ② Traditional SRP group. The affected teeth were treated by ultrasonic subgingival scaling and hand root planing with a Gracey curette. ③ Untreat group. The above operations were performed by the same senior physician. Under local anesthesia, each tooth was scraped for 10 minutes and then extracted. The residual amount of calculus on the root surface after plaque staining was observed and recorded. The thickness of the retained cementum at 1/3 of the root neck was measured.@*Results@# The residual rate of calculus on the root surface was the lowest in the endoscope-assisted SRP group, which was significantly different from the traditional SRP group and the untreated group (P < 0.001). Histological observation showed that the mean residual cementum thickness at 1/3 of the root neck increased gradually from the cemento-enamel junction (CEJ), 2.5 mm below the CEJ and 5 mm below the CEJ. Ultrasound SRP assisted by endoscopy caused less damage to the cementum and preserved the cementum better than traditional subgingival scaling (P < 0.001). @*Conclusion@# Compared with traditional SRP therapy, endoscope-assisted SRP treatment can remove subgingival plaque and calculus more effectively and can better preserve the cementum of the root surface.