The use of cortical heterologous sheets for sinus lift bone grafting: a modification of Tulasne's technique with 7-year follow-up.

In this article, the authors describe their experience with using cortical deantigenated equine bone sheets in sinus lift grafting procedures performed on 23 patients. The technique employed resembles that described by Tulasne but avoids the need for using harvested calvaria bone and introduces some additional operating variants. The use of heterologous cortical bone sheets effectively managed even large lacerations of the Schneiderian membrane and allowed for immediate stabilization of the heterologous bone granules. Average histomorphometric values for bone cores collected six months after grafting, at the time of implant placement, were: newly formed bone tissue, residual bone substitute, medullary spaces. At seven year follow-up, clinical and radiographic examination indicated that the use of the bone sheets preserved the regenerated bone volume. In conclusion, the use of heterologous cortical bone sheets in association with granular bone graft material enabled long-term stabilization of the graft material and effective management of intra-surgical complications.

A possible novel objective intraoperative measurement of maxillary bone density.

AIM: Implant survival and success rates are strictly related to the density of the bone they are placed in. Bone density, in fact, affects both implant primary stability and implant micromovements after implant positioning. Current bone density classifications rely on subjective, scarcely reproducible evaluations. A novel implant micro motor featuring a bone density measurement probe has been recently introduced. The objective of this study was to test such bone density measurement system for its capability of distinguishing different bone density areas in the upper and in the lower jaw. METHODS: 1254 implant placement sites had their bone density measured during standard implant placement at a single clinical facility. After data collection bone density distribution was statistically analyzed in order to test the hypothesis of a non-homogeneous distribution in four different predefined anatomical maxillary zones, namely pre-antral (between teeth from 14 to 24) and sub-antral (more distally) in the upper maxilla and interforaminal (between and including teeth from 34 to 44) and retroforaminal (more distally) zone. RESULTS: Measured bone density values, organized according the named four anatomical zones, produced a statistically significant inhomogeneous pattern (P<0.001). Density distribution was consistent with data from literature, but not always corresponding with the one achieved by applying the well known Misch classification. CONCLUSION: The measuring system we tested allowed to distinguish different and clinically significant anatomical zones according to their different bone density, and can represent a fundamental diagnostic tool to plan the proper implant placement steps.

Treatment of a bone defect consequent to the removal of a periapical cyst with equine bone and equine membranes: clinical and histological outcome.

AIM: While deproteinized bovine bone and bovine membranes have been well studied and can yield good results when used to treat bone defects and peri-implant dehiscences, enzymatically deantigenated equine bone and equine membranes have emerged as possible alternative biomaterials. The objective of this study was the clinical and histological assessment of such materials: equine bone granules, an equine collagen membrane and an equine pericardium membrane. METHODS: Enzymatically deantigenated equine bone and an equine collagen membrane were used to restore a bone defect caused by the removal of a bone cyst in the upper anterior maxilla. After 4.5 months, an implant was placed and a bone core sample was obtained from the grafted site. Implants threads, though, were exposed. This defect was grafted with a mixture of autogenous and equine bone and covered with an equine pericardium membrane. RESULTS: Four months after implant placement the peri-implant bone levels were maintained. A prosthesis was delivered three months later providing functional and esthetic rehabilitation. Also four-year follow-up controls showed implant success. Histological analysis of the bone core revealed that the graft material had undergone remodelling, and a fair amount of newly formed vital bone was present at the time of sample collection. CONCLUSION: The deantigenated equine bone is biocompatible and undergoes osteoclastic remodelling. Both the equine collagen and pericardium membrane acted as effective barriers for guided bone regeneration.