title: Learning root debridement with curettes and power-driven instruments. Part II: Clinical results following mechanical, nonsurgical therapy.
abstract: OBJECTIVE
  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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Department of Periodontology, School of Dentistry, University of Kiel, Kiel, Germany Unit of Periodontology, School of Dentistry, University of Greifswald, Greifswald, Germany. reuhling@konspar.uni-kiel.de
authors.forename: A
authors.initials: A
authors.lastname: Rühling
authors.forename: J
authors.initials: J
authors.lastname: König
authors.forename: H
authors.initials: H
authors.lastname: Rolf
authors.forename: T
authors.initials: T
authors.lastname: Kocher
authors.forename: C
authors.initials: C
authors.lastname: Schwahn
authors.forename: H C
authors.initials: HC
authors.lastname: Plagmann
mesh_terms: D003754:Dental High-Speed Equipment; D003762:Dental Instruments; D012534:Dental Scaling / Q000295:instrumentation*; D006801:Humans; D008348:Manikins; D010512:Periodontal Index; D010517:Periodontics / Q000193:education* / Q000295:instrumentation; D010518:Periodontitis / Q000628:therapy*; D014092:Tooth Root; D016896:Treatment Outcome