Histologic evaluation of recombinant human platelet-derived growth factor-BB after use in extraction socket defects: a case series.

Recent advancements in the arena of therapeutic molecular enhancement have shown favorable clinical findings for periodontics. However, further studies to optimize clinical outcomes using this technology are warranted. Twelve premolar extraction sockets were assigned randomly for treatment with 0.3 mg/mL recombinant human platelet-derived growth factor (rhPDGF-BB) combined with either a collagen containing anorganic deproteinized bovine bone (xenograft) or beta-tricalcium phosphate (b-TCP). Histologic evaluation of extraction socket healing was performed at 3 months. Histologic findings were similar with b-TCP and the xenograft, having 21% and 24% vital bone, respectively. The use of rhPDGF-BB with either b-TCP or a xenograft resulted in uneventful socket healing. At reentry, all implants were placed without the need for further grafting, and 100% implant success was recorded at the time of final evaluation (restoration completion).

Histologic evaluation of a stem cell-based sinus-augmentation procedure.

BACKGROUND: Predictability has been demonstrated for the long-term success of dental implants placed simultaneously with or after a sinus-augmentation procedure. However, the time required to obtain optimal bone formation can be from 6 to 9 months or longer with grafting materials other than autogenous bone. For this reason, there is interest in a surgical technique that does not require the harvest of autogenous bone but still results in sufficient bone formation within a relatively short time frame. METHODS: The purpose of this case series was to evaluate the bone formation following sinus-augmentation procedures using an allograft cellular bone matrix containing native mesenchymal stem cells. Biopsy and histologic evaluation were performed after approximately 4 months of healing. RESULTS: Histomorphometric analysis revealed an average vital bone content of 33% (range, 22% to 40%) and an average residual graft content of 6% (range, 3% to 7%) for the five cases reported that had an average healing period of 4.1 months (range, 3 to 4.75 months). CONCLUSION: The high percentage of vital bone content, after a relatively short healing phase, may encourage a more rapid initiation of implant placement or restoration when a cellular grafting approach is considered.

Bone augmentation techniques.

BACKGROUND: The advent of osseointegration and advances in biomaterials and techniques have contributed to increased application of dental implants in the restoration of partial and completely edentulous patients. Often, in these patients, soft and hard tissue defects result from a variety of causes, such as infection, trauma, and tooth loss. These create an anatomically less favorable foundation for ideal implant placement. For prosthetic-driven dental implant therapy, reconstruction of the alveolar bone through a variety of regenerative surgical procedures has become predictable; it may be necessary prior to implant placement or simultaneously at the time of implant surgery to provide a restoration with a good long-term prognosis. Regenerative procedures are used for socket preservation, sinus augmentation, and horizontal and vertical ridge augmentation. METHODS: A broad overview of the published findings in the English literature related to various bone augmentation techniques is outlined. A comprehensive computer-based search was performed using various databases that include Medline and PubMed. A total of 267 papers were considered, with non-peer-reviewed articles eliminated as much as possible. RESULTS: The techniques for reconstruction of bony defects that are reviewed in this paper include the use of particulate bone grafts and bone graft substitutes, barrier membranes for guided bone regeneration, autogenous and allogenic block grafts, and the application of distraction osteogenesis. CONCLUSIONS: Many different techniques exist for effective bone augmentation. The approach is largely dependent on the extent of the defect and specific procedures to be performed for the implant reconstruction. It is most appropriate to use an evidenced-based approach when a treatment plan is being developed for bone augmentation cases.

Modified semilunar coronally advanced flap.

BACKGROUND: Correction of mucogingival recession deformities with a variety of periodontal plastic surgery procedures has been described, each demonstrating a variable degree of success. A modified semilunar coronally advanced flap is described for the treatment of recession defects on multiple adjacent teeth. METHODS: Semilunar incisions were made apical to the recession defects, starting within mucosa and extended mesio-distally, arching more coronally to terminate apical to the papillae mesial and distal to the teeth exhibiting the defects. The papilla between the teeth with recession was coronally advanced after a split-thickness dissection and sutured more coronally, over the deepithelialized portion of the original papilla. The flap design gave better mobility and stability to the repositioned pedicle than previously described semilunar coronally advanced flap procedures. RESULTS: Seven cases treated with this approach healed without complication and remained stable throughout the 8 to 22 months of post-surgical observation. CONCLUSIONS: This technique will be particularly valuable when previous attempts for root coverage with soft tissue autografts have resulted in residual recession defects on adjacent teeth and in a thicker-tissue biotype that would be amenable to partial-thickness dissection. An adequate thickness of tissue that will allow a partial-thickness flap dissection is required to avoid tooth or alveolar bone fenestrations. This technique provides better control over flap repositioning than previously described semilunar coronally advanced flaps.

Squamous odontogenic tumor: diagnosis and management.

The squamous odontogenic tumor (SOT) is a rare, benign, locally infiltrative neoplasm of the jaws that appears to originate from the rests of Malassez. It has been confused with other pathologic entities such as ameloblastomas, carcinomas, and fibromas and clinically may resemble localized periodontal disease. The tumor is often asymptomatic, although it can present with symptoms of pain and tooth mobility. A characteristic radiographic appearance is that of a triangular-shaped or semi-circular lucency associated with the roots of erupted teeth. Histologically, the tumor is characterized by the formation of variably sized nests and cords of uniform, benign-appearing, squamous epithelium with occasional vacuolization and keratinization. Treatment of SOT by conservative surgical excision is normally curative with rare episodes of recurrence reported. Since the clinical presentation of SOT may mimic more common pathologic entities, this case report reinforces the need for careful histologic evaluation of all lesions found in the periodontium.