Title: Stability and Osseointegration in Piezo-Implants Versus Cylindrical Implants
Trevor Fujinaka (Presenter)
Lorena Corzo, Boston University
Wanpeng Xu, Boston University
Taisuke Ohira, Boston University
Serge Dibart, Boston University
Objectives: Piezoelectric surgery has shown encouraging effects on healing and is utilized to split narrow alveolar ridges before implant placement. A new wedge-shaped titanium “Piezo-implant” requires piezoelectric osteotomy instead of conventional rotary instrumentation. This study measured stability, osseointegration, and alveolar ridge changes comparing “Piezo-implants” and conventional threaded cylindrical implants.
Methods: 3 months post-extraction, 18 conventional cylindrical implants (Nobel ActiveTM) and 18 wedge-shaped “Piezo-implants” were placed in a split-mouth design in 3 minipigs (n = 36). The cylindrical implant sites were prepared with rotary instrumentation while the “Piezo-implant” sites were prepared using piezoelectric surgical inserts (Fraunhofer CMI). Implant stability was tested (Periotest®) immediately after implant placement and after euthanization at 4, 8, and 12 weeks. Quantitative microCT analysis (Scanco Medical®) assessed peri-implant alveolar bone volume and osseointegration. Histologic and histomorphometric measurements evaluated peri-implant healing and bone-to-implant contact. Submicron x-ray imaging determined bone structure along the implant surfaces.
Results: The stability of “Piezo-implants” was significantly greater compared to cylindrical implants at 4, 8 and 12 weeks (P<0.05). A multiple linear regression model (R-square=0.69) demonstrated a significantly higher bone volume fraction (BV/TV) in the mandible (t ratio=6.21, p<0.01), significant increase of BV/TV over time (t ratio=5.21, p<0.01), and significantly higher average BV/TV in “Piezo-implants” (t ratio=-2.38, p<0.01). Histological evaluations demonstrated that “Piezo-implants” had a greater % BIC at 4 and 12 weeks, a greater new bone growth % at all time points, and a slight increase in bone maturation at 12 weeks when compared to the cylindrical implants. High-resolution x-ray imaging exhibited a tighter interface between implants and alveolar bone formation in the “Piezo-implants”.
Conclusions: “Piezo-implants” had a more desirable healing, greater stability, and may be suited for narrow ridge spaces without additional ridge augmentation. Thus, the novel wedge-shaped “Piezo-implant” system should be considered a viable option in cases with narrow alveolar bone. Further research is needed to establish clinical validity.