Cleaning Effectiveness and Surface Roughness of Ultrasonic Driven Periodontal Instruments

Objectives: The aim of the present in vitro-study was to evaluate the cleaning effectiveness of different ultrasonic driven slim curved periodontal instruments to remove artificial debris from molar roots and the resulting surface roughness. Methods: 30 human molars were randomly selected into 6 groups. All roots were covered with artificial calculus. Teeth of each group were mounted in line into silicone. Periodontal pockets were simulated with a width of 0.5 mm. The root surfaces were cleaned using the following combinations of ultrasonic systems and instruments within 5 min: Piezon Master (PM) 400 with PL 1/2 (A), PM700 with PL1/2 (B), CavitronJetPlus with Dentsply FSI 10R/L (C), Symmetrie IQ3000 with Hu-Friedy US4L/R (D), Perio Scan with Sirona-PE2/3 (E) and manual curettes for control (X). Afterwards the roots were photographed. The approximal (AP) and buccal/ oral (BO) areas that could be cleaned as well as those with remaining calculus were assessed computer assisted. Surface roughness RA was measured profilometrically. Statistical analysis was carried out (one-way ANOVA, Bonferroni/Dunn correction, t-test, α=0.05). Results: Generally, calculus could be cleaned at least as efficient as manually (X: 72±28%) with all ultrasonic driven instruments. PM700 and CavitronJet (B: 92±11%, C: 96±15%) obtained best results with C-BO being significantly higher than X (p<0.0003). PM700 performed not significantly better than PM400 (A: 88±13%). D with scaling instrument tips showed no advantage compared to rounded curved instrument tips of the other ultrasonic groups (A-C,E). No significant differences were found between BO-AP sides (p>0.05). Resulting surface roughness varied between 5.1±2.3µm (C) and 9.3±5.9 (B) with no significant differences between all groups (p>0.05). Conclusions: All ultrasonic driven systems with periodontal instruments were able to clean at least as effective and with comparable smoothness as manual curettes and without differences regarding the root side. The effectiveness depended on power device and instrument tip.