Use of particulate dentin-plaster of Paris combination with/without platelet-rich plasma in the treatment of bone defects around implants

PURPOSE: To evaluate the effect of particulate dentin-plaster of Paris with and without platelet-rich plasma (PRP) on bone healing and new bone formation around titanium dental implants in a canine model. Histologic sections and histomorphometric analysis of the defects were obtained at 6 and 12 weeks after surgery. MATERIALS AND METHODS: Three circular bone defects were surgically prepared in iliac crest sites in each of 10 animals. A total of 30 Avana dental implants were placed in the animals. They were self-tapping, screw-type implants, 10 mm in length and 4 mm in diameter, all made of commercially pure titanium. A titanium implant was placed centrally in each defect. In each dog, the defects were treated with 1 of the following 3 treatment modalities: (1) no treatment (control); (2) grafting with particulate dentin-plaster of Paris; (3) grafting with particulate dentin-plaster of Paris and PRP. RESULTS: Histologic analysis showed that all of the bone defects surrounding the implants that were treated with particulate dentin-plaster of Paris, with and without PRP, were filled with new bone. The defects that were not treated (control) demonstrated new bone formation only in the inferior threaded portion of the implants. DISCUSSION: Histomorphometric results revealed a higher percentage of bone contact with particulate dentin-plaster of Paris and PRP compared to the control and particulate dentin-plaster of Paris. CONCLUSIONS: These results suggested that bone defects around titanium implants can be treated successfully with particulate dentin-plaster of Paris, and that the outcome can be improved if PRP is also used.     

Focal osteoporotic bone marrow defects of the jaws

Twenty focal osteoporotic bone marrow defects of the jaws were analyzed clinically, histologically, and radiographically; the findings were compared with those from all known published cases. Radiologic and clinical criteria that are useful for making a definitive diagnosis are discussed, and five radiologic categories are proposed.     

Growth factor-mediated combination therapy to treat large local human alveolar ridge defects

The purpose of this case report is to demonstrate the effectiveness of a matrix consisting of recombinant human platelet-derived growth factor BB (rhPDGF-BB)-hydrated cancellous allogenic block graft in the reconstruction of large local human alveolar ridge defects. The results suggest improved bone regeneration when combining rhPDGF-BB with the allogenic block graft. The clinical and histologic evidence of new bone formation as well as bone remodeling supports the clinical potency of this growth factor-mediated therapy.     

Grafting of the buccal fat pad into palatal defects

Grafting of the buccal fat pad was performed in combination with lyophilized porcine dermis in six cases of palatal defects. The use of lyophilized porcine dermis not only simplified the surgical procedure but also permitted a proper prosthetic rehabilitation. This technique proved to have more advantages for palatal defects.     

Myoxomas of the jaws.

A retrospective study on 15 patients with myxomas of the jaws was carried out. Follow-up information was obtained in 10 patients. Clinical, radiologic, and microscopic features were examined and the results of extensive resection versus conservative surgery were evaluated. The results seem to be in favor of the latter. Four cases are presented in detail.     

Reconstruction for large defects of the scalp and cranium.

Thirty-one patients with large scalp and cranium defects were reconstructed with free tissue transfer and scalp flaps. Twenty-eight of the defects resulted after tumour resection, two after infection and one after an extensive burn. Thirty-one free flaps (mainly the latissimus dorsi myocutaneous and the radial forearm fasciocutaneous) and five large (> 200 cm2) scalp flaps were used. Major complications occurred in one patient who developed meningitis and finally died (3.2%), and in one patient who lost a latissimus dorsi flap (3.2%). There were no other significant problems with the remaining patients. All other free flaps and scalp flaps survived. Primary reconstruction with free tissue transfer was our first choice of treatment because of the wide spectrum of advantages of free flaps. However, in a limited number of cases there was an indication for large scalp flaps, which, when properly designed, gave satisfactory results.     

血管化骨移植修复颌骨严重缺损并种植义齿修复

目的:颌骨外伤、肿瘤或其他疾病常导致上下颌骨严重缺损,此时如何重建口腔颌面部的形态和功能一直是口腔修复的难点和挑战。本研究旨在观察血管化骨移植修复颌骨缺损并种植义齿修复的临床效果。方法:对12例颌骨严重缺损患者行血管化髂骨肌瓣或血管化腓骨肌皮瓣修复骨缺损,对牙列缺损患者采用手术导板指导移植骨块的定位,7例患者在导板指导下行同期牙种植体植入术。5例患者在术后4～6月行延期牙种植体植入术。3～4月后行种植义齿修复,其中种植覆盖义齿4例,种植固定义齿8例。结果:所有病例的血管化自体骨移植均获成功。种植义齿修复后经3～24月的临床观察,X片显示种植体与移植骨间未见透射影,2例发生种植体周围软组织增生,患者对形态和功能恢复感到满意。结论:血管化骨移植并种植义齿修复用于颌骨严重缺损的功能重建可获得良好的临床效果,其远期疗效有待进一步观察。     

Cholesterol granuloma of the jaws. Report of a case

A case of a cholesterol granuloma of the mandible, which manifested as a solitary radiolucent lesion in an edentulous area, is presented. There is a lack of accurate data regarding its nomenclature and pathogenesis. In this report, the literature is reviewed, the nomenclature is clarified and the pathogenesis discussed.     

Extracondylar osteochondromas of the jaws.

A review of the literature and the addition of two new cases have revealed that according to a histologic criterion there are presently twenty reported cases of osteochondroma of the jaws located outside the condyles. Although most of the extracondylar lesions have occurred on the coronoid process, cases are now reported on the maxilla and the body of the mandible. The clinical features of these lesions are compared with those located in the condyle, and the radiographic and surgical approaches of the extracondylar lesions are discussed.