Learning root debridement with curettes and power-driven instruments. Part II: Clinical results following mechanical,nonsurgical therapy

BACKGROUND, AIMS: In a manikin study we recently assessed how effectively student operators were able to learn scaling with curettes (GRA) and power-driven instruments (PP). Calculating the debrided root area effectiveness was low in both groups without systematic training or without a motivational program. After 10 weeks (20 h) of training, operators reached a high effectiveness of 84.7% (GRA) and 81.6% (PP). The purpose of the present study was to evaluate the clinical outcome of nonsurgical treatment as performed by these student operators. METHODS: In a clinical trial, 19 students trained in the use of Gracey curettes for 10 weeks (=20 h) (GRA10) and Periopolisher system for 1 week (=2 h) (PP1), and 20 students trained in the use of Gracey curettes for 1 week (GRA1) and the Periopolisher for 10 weeks (PP10) treated one patient each in a split-mouth design. At baseline and 6 months, we recorded probing depth (PD), probing attachment level (PAL) and bleeding on probing (BOP) by computer-assisted probing. Statistical analysis was carried out for moderate (category B) and deep sites (category C). Groups were compared using Student's t-tests (p<0.05). RESULTS: Category B sites showed a PD reduction of 1.2/1.0 mm (GRA10/GRA1) and 1.1 mm (PP10/PP1). PAL gain was 0.5/0.3 mm (GRA10/GRA1) and 0.4/0.2 mm (PP10/PP1). In category C sites, PD reduction was 2.1/2.3 mm (GRA10/GRA1) and 2.0 mm (PP10/PP1) with a PAL gain of 0.6/0.9 mm (GRA10/GRA1) and 0.4 mm (PP10/PP1). BOP was significantly lower in all groups. CONCLUSION: The results show that student operators who had received a systematical training on manikins and had attained different effectiveness results were able to treat periodontally diseased patients successfully using both Gracey and Periopolisher instruments.