Autogenous bone ridge augmentation using the mandibular symphysis as a donor.

Potential host sites often present less than optimal dimensions or quality than are required for implant placement. This paper emphasizes a variety of surgical technique designed to optimize these areas. There are a number of anatomic sites available to serve as donors for autogenous bone grafting. They include the tibial plateau, the calvarium, the mandibular rami, the iliac crests and the symphysis of the mandible. Although each has the potential of presenting risks, the symphysis serves a singularly beneficial source. The techniques of harvesting bone, and utilizing it for a variety of grafting procedures is described, the benefits of such utilization are emphasized and the risks of such operations are reviewed.

An in vitro comparison of the computerized tomography/CAD-CAM and direct bone impression techniques for subperiosteal implant model generation.

Subperiosteal implants are currently fabricated by using the classic two-stage direct bone impression technique or by the use of the one-stage computer tomography/computer-assisted design-computer-assisted manufacture (CT/CAD-CAM) method. This study compares the accuracy of the two techniques by using cadaver maxillae and mandibles as the models for fabrication of casts. Seven cadaver jaw specimens were collected and subjected to direct bone impressions and to CT scans. Those derived from the direct bone impressions were poured in die stone, while the CT scans were sent for fabrication of CAD-CAM-generated casts. On each of the 14 models so produced, a cast grid was fabricated that was designed as a measuring device. The preciseness of fit of each grid was subjected to analyses that presented levels of accuracy. Statistical evaluation of these levels, reduced to numerical indices, revealed that the direct bone techniques resulted in acceptable castings in seven of seven cases, whereas the CAD-CAM method yielded adequate castings in five of seven cases.

The role of incision design and location in the healing processes of alveolar ridges and implant host sites.

This research examined the nature and role of a linea alba, found consistently at the crest of edentulous ridges in dogs. Angiovist dye was used to outline the microvasculature in these regions. The findings demonstrated a zone of avascularity directly beneath each linea alba. When novel incision designs were used in the gingivae and the outlined mucoperisteal flaps were elevated and then replaced, alterations in underlying bone morphology were noted. In a subsequent study during which implants were placed, a direct relationship was noted between incision design and level of pericervical bone support.

Evaluation of the Periotest as a diagnostic tool for dental implants.

The Periotest is examined as a possible replacement for outdated, inconsistent dental implant stability diagnosis tools. The Periotest has the advantage of offering reproducible findings by measuring the levels of subclinical mobility using an ultrasonically vibrating probe. The Periotest is successful in assessing the stability status of an implant, but it can detect the quantity of bony osseointegration only in terminal cases. Radiography proved to be a more sensitive method of determining pericervical bone loss; therefore, periapical radiographs in addition to the Periotest device were found to offer the most reliable assessment of an implant's status.

A human clinical and histologic report of an osseointegrated titanium alloy root form implant.

Endosteal implants fail for a variety of reasons. These include failure to osseointegrate, long-term loss of osseointegration, and invasion of a vital structure or anatomic placement that prohibits its use. This case report describes the removal of an implant because of patient discomfort secondary to invasion of the mandibular canal. These histologic findings offered a unique opportunity to examine an osseointegrated human dental implant section.

Management of the iatrogenically displaced anterior sublingual floor.

Trauma and neoplasms may be responsible for ablative procedures performed in the anterior mandibular region. This surgery, as well as alveoloplasty, ridge augmentation, and placement of subperiosteal implants, may be responsible for the anterior malpositioning of the floor of the mouth along with its adnexa, which brings Wharton's carunculae directly over the crest of the ridge. A technique has been devised to correct this problem.

A modified occlusal registration and implant transfer technique.

The technique for the transfer of implant and abutment position to a working cast has been hindered by multiple transfers and record reproductions. These serve only to delay completion of the patient's prosthetic requirements. A transfer technique that uses custom impression trays fabricated from surgical templates allows for a single-visit transfer of centric occlusion, vertical dimension, tooth position, and implant or abutment location in one procedure. This streamlines treatment and allows for quicker delivery of final prostheses.

The use of a particulate, microporous, calcified copolymer as a ridge maintenance device in dogs.

HTR polymer Synthetic Bone was found to be an osteoconductive, biocompatible, reliable nonresorbable matrix ridge maintenance material (Ridge Preservation). When used as socket implants immediately after the extraction of teeth over a one-year period in 16 beagle dogs, HTR was observed clinically and radiographically and compared with controls (unimplanted, sutured) extraction sites. As the control areas resorbed, the stability and effectiveness of the synthetic bone material in the operative sites became more clearly delineated. Quantitative analyses could not be made using radiographic techniques, but radiographs supported by subjective clinical observations as well as study casts taken of the height and width of the implanted areas, showed greater ridge retention compared with controls. Histological sections demonstrated dense laminar bone gradually forming into and around the HTR particulate material.