title: Comparison of Er:YAG laser, piezoelectric, and drill osteotomy for dental implant site preparation: a biomechanical and histological analysis in sheep.
abstract: OBJECTIVE
  The aim of this study was to examine the influence of implant bed preparation, using either Er:YAG laser ablation, piezoelectric surgery or drill osteotomy, on osseointegration of titanium dental implants after 4, 6, and 8 weeks.
  
  
  METHODS
  A total of 108 implants (Camlog) were placed in the pelvis of 6 sheep (18 implants/sheep). Implant sites were prepared by an Er:YAG laser, a dental drill or a piezoelectric device. For each time period, six implants were used for biomechanical removal torque testing and six implants for a semi-quantitative histological assessment of the bone-to-implant contact (BIC).
  
  
  RESULTS
  An initially missing implant adjusted site preparation led to slightly higher BIC and torque values in the piezoelectric and laser groups due to a press-fit effect after 4 weeks. Statistical analysis of the average mean BIC after 4, 6, and 8 weeks revealed no significant differences (P > 0.05) between the different osteotomy techniques. Comparison of individual removal torque values showed the highest value for laser osteotomy after 8 weeks (1,698.50 +/- 67.52 Nmm), which was significantly higher than the corresponding value for drill osteotomy (P = 0.006).
  
  
  CONCLUSIONS
  Although BIC and removal torque values decreased in the laser and piezoelectric groups at 6 weeks during an active remodeling process, favorable and superior BIC as well as torque values could be demonstrated at 8 weeks. Thus laser and piezoelectric osteotomy seem to be at least comparable to drill osteotomy, concerning early osseointegration and implant stability.
authors.affiliation: Competence Center for Applied Biotechnology and Molecular Medicine, University of Zürich, Winterthurerstr. 260, CH-8057 Zürich, Switzerland. stefan.stuebinger@cabmm.uzh.ch
authors.forename: Stefan
authors.initials: S
authors.lastname: Stübinger
authors.forename: Kristina
authors.initials: K
authors.lastname: Biermeier
authors.forename: Beatus
authors.initials: B
authors.lastname: Bächi
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Ferguson
authors.forename: Robert
authors.initials: R
authors.lastname: Sader
authors.forename: Brigitte
authors.initials: B
authors.lastname: von Rechenberg
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D016723:Bone Remodeling; D001842:Bone and Bones / Q000000981:diagnostic imaging / Q000473:pathology; D003757:Dental Implantation / Q000379:methods*; D015921:Dental Implants; D005260:Female; D053685:Laser Therapy; D053844:Lasers, Solid-State / Q000627:therapeutic use*; D023421:Models, Animal; D016348:Osseointegration; D010027:Osteotomy / Q000379:methods*; D010388:Pelvis; D011182:Postoperative Care; D011859:Radiography; D012756:Sheep; D014025:Titanium
chemical_list: D015921:Dental Implants; D014025:Titanium