A digital technique for fabricating an interim implant-supported fixed prosthesis immediately after implant placement in patients with complete edentulism

The conversion of a denture into an interim implant-supported, screw-retained restoration has become the standard method for immediate interim restoration in patients with complete edentulism. The most critical steps of the denture conversion process are the creation of appropriate denture access holes to prevent displacement of the denture by the interim cylinders and removal of the denture flanges to facilitate both good esthetics and accessibility for oral hygiene after the denture is connected to the interim cylinders. This article presents a digital technique for designing and fabricating an interim implant-supported, fixed prosthesis for edentulous patients. The interim prosthesis has cylinder access holes that are digitally prefabricated and a denture flange part that is designed to be easily sectioned. This technique facilitates more straightforward and efficient immediate restoration for edentulous patients after implant placement.     

The effects of exposing dental implants to the maxillary sinus cavity on sinus complications.

OBJECTIVE: The aim of this study was to investigate whether dental implant exposure to the maxillary sinus cavity increases the risk of maxillary sinus complications. STUDY DESIGN: An implant was placed bilaterally in the maxillary sinus of 8 adult female mongrel dogs in a way that it penetrated the bone and mucous membrane of the maxillary sinus floor to the extent of 2 mm, 4 mm, or 8 mm. The implants were left in place for 6 months. RESULTS: Radiographic and histologic examinations did not show any signs of pathologic findings in the maxillary sinus of the 8 dogs. CONCLUSION: This study indicates that implant protrusion into the maxillary sinus cavity is not related to the development of sinus complications in canines.     

A comparative histologic analysis of tissue-engineered bone using platelet-rich plasma and platelet-enriched fibrin glue.

OBJECTIVE: The aim of this study was to compare the effects of platelet-rich plasma (PRP) and platelet-enriched fibrin glue on bone formation in bone tissue engineering. STUDY DESIGN: PRP was mixed with bone marrow mesenchymal stem cells and bone morphogenetic protein-2 (BMP-2), and the composites were injected into the subcutaneous space on the dorsum of nude mice. On the contralateral side of the dorsum, platelet-enriched fibrin glue/bone marrow mesenchymal stem cells/BMP-2 composites were injected. Bone formation was evaluated after 12 weeks. RESULTS: The volumes of subcutaneous nodules formed in nude mice were 55 +/- 18 microL at the PRP/bone marrow mesenchymal stem cells/BMP-2 sites and 135 +/- 27 microL at the platelet-enriched fibrin glue/bone marrow mesenchymal stem cells/BMP-2 sites. Histomorphometric analysis demonstrated that the nodules contained 14.9 +/- 4.1% newly formed bone when using PRP and 19.8 +/- 3.6% newly formed bone when using platelet-enriched fibrin glue. CONCLUSION: The results indicated that the osteogenic characteristics of platelet-enriched fibrin glue are superior to PRP in bone tissue engineering.     

Learning curve for gastric cancer surgery based on actual survival

Gastric Cancer - The aim of this study was to investigate learning curves for surgeons performing D2 lymph node dissection based on actual patient survival. A total of 3,284 patients with gastric...     

Cyanoacrylate adhesive for closing sinus membrane perforations during sinus lifts

INTRODUCTION: Sinus lift procedures depend greatly on fragile structures and anatomical variations. The procedure may cause sinus membrane perforations, which can lead to graft infection and early failure. AIM: To assess the efficacy of cyanoacrylate adhesive in the management of large perforations of the maxillary sinus membrane during sinus lifts. MATERIAL AND METHODS: Six rabbits were used in the study. Sinus membrane perforations (about 1.5 cm in length) were repaired with cyanoacrylate adhesive on one side of the maxillary sinus. On the contralateral side, an identical laceration was not repaired. Histological evaluation was performed 2 weeks after the operation. RESULTS: Wounds repaired with cyanoacrylate adhesive showed newly formed continuous epithelium across the previous perforation site and there was sinusitis on the contralateral side. CONCLUSION: These results support the clinical use of cyanoacrylate adhesive for repairing sinus membrane perforations.     

Platelet-enriched fibrin glue and platelet-rich plasma in the repair of bone defects adjacent to titanium dental implants

PURPOSE: The aim of this study was to compare the effects of platelet-enriched fibrin glue and platelet-rich plasma (PRP) on the repair of bone defects adjacent to titanium dental implants. MATERIALS AND METHODS: In 6 mongrel dogs, 3 screw-shaped titanium dental implants per dog were placed into the osteotomy sites in the tibia. Before implantation, a standardized gap (2.0 mm) was created between the implant surface and the surrounding bone walls. Six gaps were left empty (control group), 6 gaps were filled with autogenous particulate bone mixed with PRP (PRP group), and 6 gaps were filled with autogenous particulate bone mixed with platelet-enriched fibrin glue (fibrin glue group). RESULTS: After 6 weeks, the bone-implant contact was 59.7% in the fibrin glue group, 29.2% in the PRP group, and 10.2% in the control defects; this difference was statistically significant (P < .05). DISCUSSION AND CONCLUSION: Greater bone-implant contact was achieved with platelet-enriched fibrin glue than with PRP. The results indicate that platelet-enriched fibrin glue can induce a stronger peri-implant bone reaction than PRP in the treatment of bone defects adjacent to titanium dental implants.     

A comparative study of the posterolateral and anterolateral approaches for isolated acetabular revision

Purpose  

Although isolated revision of the acetabular component has become an increasingly common option for revision hip surgery, opinions differ regarding the ideal surgical approach for reducing postoperative instability. The purpose of this study was to compare the clinical and radiographic results of isolated acetabular revision performed using a posterolateral and an anterolateral approach.     

Injectable bone using chitosan-alginate gel/mesenchymal stem cells/BMP-2 composites.

AIM: Several injectable materials have been used as osteogenic bone substitutes. However, none has gained universal acceptance. This study was performed to investigate whether or not chitosan-alginate gel/mesenchymal stem cells/bone morphogenetic protein-2 composites are potentially injectable materials for new bone formation. MATERIAL AND METHODS: The composites were injected into the subcutaneous space on the dorsum of nude mice to investigate new bone tissue formation. The composites were examined histologically over a 12-week period. RESULTS: The composites injected into the mouse were able to stimulate new bone formation, which was trabecular in type. CONCLUSIONS: This study showed that chitosan-alginate gel/MSCs/BMP-2 composites could become clinically useful injectable materials to generate new bone.