Surgical Prosthodontics--A Shift in Patient Treatment at the University of Tennessee Graduate Prosthodontic Program (Case Report].

Over recent years Dentistry has evolved, and as such, we have been able to make strides in restoring edentulous patients with dental implants. Recently, the specialty of Prosthodontics, in addition to the prosthetic rehabilitation of complex dental patients with fixed, removable, implant, and cosmetic dental needs, has begun to shift into the surgical realm of patient treatment. This report outlines a minimally invasive technique for sinus floor elevation, on the controlled use of drills and osteotomes, while simultaneously placing implants through a guided protocol. The rational for such a technique is that it provides a predictable and repeatable method of attaining vertical ridge augmentation as well as correct implant placement in order to obtain ideal restorative reconstructions. In addition it provides the dentist with the autonomy to treat patients requiring implants from start to completion with a great deal of control. Postoperative radiographs reveal the amount of vertical height gained and concomitant implant placements.

A systematic approach to definitive planning and designing single and multiple unit implant abutments.

With an increase in the availability of implant restorative components, the selection of an appropriate implant abutment for a given clinical situation has become more challenging. This article describes a systematic protocol to help the practitioner more thoughtfully select abutments for single and multiple unit fixed implant prostheses. The article examines the evaluation, planning, design, and fabrication processes for the definitive restoration. It includes an assessment of a variety of factors, namely restorative space, soft and hard tissues, the location of the implant platform, the type of platform connection, platform switching indications, tissue collar heights, emergence profile, implant angulation, and finally the design and esthetic options for the final implant abutment.

Nanometer-scale features on micrometer-scale surface texturing: a bone histological, gene expression, and nanomechanical study.

Micro- and nanoscale surface modifications have been the focus of multiple studies in the pursuit of accelerating bone apposition or osseointegration at the implant surface. Here, we evaluated histological and nanomechanical properties, and gene expression, for a microblasted surface presenting nanometer-scale texture within a micrometer-scale texture (MB) (Ossean Surface, Intra-Lock International, Boca Raton, FL) versus a dual-acid etched surface presenting texture at the micrometer-scale only (AA), in a rodent femur model for 1, 2, 4, and 8weeks in vivo. Following animal sacrifice, samples were evaluated in terms of histomorphometry, biomechanical properties through nanoindentation, and gene expression by real-time quantitative reverse transcription polymerase chain reaction analysis. Although the histomorphometric, and gene expression analysis results were not significantly different between MB and AA at 4 and 8 weeks, significant differences were seen at 1 and 2 weeks. The expression of the genes encoding collagen type I (COL-1), and osteopontin (OPN) was significantly higher for MB than for AA at 1 week, indicating up-regulated osteoprogenitor and osteoblast differentiation. At 2 weeks, significantly up-regulated expression of the genes for COL-1, runt-related transcription factor 2 (RUNX-2), osterix, and osteocalcin (OCN) indicated progressive mineralization in newly formed bone. The nanomechanical properties tested by the nanoindentation presented significantly higher-rank hardness and elastic modulus for the MB compared to AA at all time points tested. In conclusion, the nanotopographical featured surfaces presented an overall higher host-to-implant response compared to the microtextured only surfaces. The statistical differences observed in some of the osteogenic gene expression between the two groups may shed some insight into the role of surface texture and its extent in the observed bone healing mechanisms.

The effect of a bioactive collagen membrane releasing PDGF or GDF-5 on bone regeneration.

Regenerative procedures using barrier membrane technology are presently well established in periodontal/endodontic surgery. The objective of this study was to compare the subsequent effects of the released platelet-derived growth factor (PDGF) and growth/differentiation factor 5 (GDF-5) from collagen membranes (CMs) on bone regeneration in vitro and in vivo. In vitro studies were conducted using MC3T3-E1 mouse preosteoblasts cultured with or without factors. Cell viability, cell proliferation, alkaline phosphatase (ALP) activity and bone marker gene expression were then measured. In vivo studies were conducted by placing CMs with low or high dose PDGF or GDF-5 in rat mandibular defects. At 4 weeks after surgery new bone formation was measured using µCT and histological analysis. The results of in vitro studies showed that CM/GDF-5 significantly increased ALP and cell proliferation activities without cytotoxicity in MC3T3-E1 cells when compared to CM/PDGF or CM alone. Gene expression analysis revealed that Runx2 and Osteocalcin were significantly increased in CM/GDF-5 compared to CM/PDGF or control. Quantitative and qualitative µCT and histological analysis for new bone formation revealed that although CM/PDGF significantly enhanced bone regeneration compared to CM alone or control, CM/GDF-5 significantly accelerated bone regeneration to an even greater extent than CM/PDGF. The results also showed that GDF-5 induced new bone formation in a dose-dependent manner. These results suggest that this strategy, using a CM carrying GDF-5, might lead to an improvement in the current clinical treatment of bone defects for periodontal and implant therapy.

A screw-connected sectional impression tray for patient with limited opening.

A procedure for fabricating a 2-piece custom tray is described. Implant analogs and gold cylinders are used to maximize the precision of the fit and the stability of the tray.

Management of the maxillary cancer patient--what the general dentist should know.

BACKGROUND: Maxillary defects are created following surgical treatment of patients with benign and malignant neoplasms, trauma or congenital defects. The size of these defects influences the degree of debilitation. CASE DESCRIPTION: This patient lacks the conventional support, stability and retention when fabrication of the prosthesis is planned. The prosthesis that is used to close this palatal defect is called the hollow bulb obturator. CLINICAL OUTCOMES: It improves speech, deglutition, esthetics and function for the patient.

A review of implant abutments--abutment classification to aid prosthetic selection.

With an increase in the availability of implant restorative components, the selection of an appropriate implant abutment for a given clinical situation has become more challenging. This article describes a classification system that will help the practitioner understand the different implant abutments available and therefore be able to understand the selection of abutments for single and multiple unit fixed implant prosthesis.