Healing at implants installed in osteotomies prepared either with a piezoelectric device or drills : an experimental study in dogs

Objective: To compare osseointegration and marginal bone level at implants placed in osteotomies prepared with either conventional drills or a piezoelectric device. Material and methods: Three months after the extraction of all mandibular premolars and first molars, two recipient sites were selected. The osteotomies were randomly prepared with either conventional drills (drill sites) or a piezoelectric device (piezoelectric sites). Implants were installed and a submerged healing was allowed. The animals were euthanized in groups of six after 4 and 8 weeks of healing. Biopsies were obtained for histological preparation. Coronal level of osseointegration (bone level) and bone-to-implant contact percentage (BIC%) were evaluated. Results: After 4 weeks of healing, the bone level was 0.6 ± 0.9 mm for the piezoelectric sites and 1.6 ± 0.7 mm for the drill sites (p = 0.173). After 8 weeks, the respective measures were 0.9 ± 0.3 mm and 1.0 ± 1.1 mm (p = 0.917). After 4 weeks of healing, a new bone apposed onto the implant surface was found at fractions of 54.9 ± 6.7% and 55.1 ± 16.6% for the piezoelectric and the drill sites, respectively (p = 0.674). The respective total bone fractions, including new and old bone, was 64.0 ± 4.8% and 63.4 ± 20.4% (p = 0.917). After 8 weeks, a new bone increased to 67.4 ± 6.7% and 62.9 ± 12.5% for the piezoelectric and the drill sites, respectively (p = 0.463). The respective total bone fractions were 70.4 ± 5.5% and 67.8 ± 12.1% (p = 0.753). Conclusions: The use of a piezoelectric device for implant site preparation is a safe procedure that allows a proper integration since the early periods of healing similar to that observed using conventional drills.