Michel Willy Richter

Human immunodeficiency virus activity in rib allografts

PURPOSE The use of bone allografts involves the risk of transmitting infectious agents from the donor to the recipient as shown by historical surveys. A study was therefore undertaken to test the hypothesis that human immunodeficiency virus (HIV) activity can still be present after the freezing and thawing of ribs taken from an acquired immune deficiency syndrome (AIDS) patient at autopsy. MATERIALS AND METHODS Rib samples were harvested under sterile conditions and frozen at -80 degrees C. After different freezing periods, the samples were cultured with activated lymphocytes. P24 antigen determination in the supernatant fluid was used to test for viral activity. RESULTS Confirmation of viral activity was obtained after freezing periods ranging from 1 to 12 weeks. CONCLUSIONS HIV activity can be found in ribs of AIDS patients, and this outlives the cryoprotection of bone banking. Donor selection remains the main security in the use of frozen bone allografts.

Occurrence of a Pyogenic Granuloma in Relation to a Dental Implant

Pyogenic granuloma is an inflammatory vascular hyperplasia often occurring in the oral cavity. It appears in response to various stimuli such as low-grade local irritation, trauma, or female steroid hormones. A 32-year-old man sought care for a tender and bleeding lesion of the left posterior maxillary gingiva. The intraoral examination showed an exophytic ulcerated nodule measuring 1.0 cm, related to a dental implant placed in the upper left second premolar position. Radiographic examination showed an oversized healing cap. A provisional diagnosis of reactive inflammatory hyperplasia was made, and the lesion was excised and submitted for histologic examination. On microscopy, the surgical specimen showed an ulcerated nodule consisting of a delicate connective tissue stroma containing numerous blood vessels with plump endothelial cells, intermingled with abundant polymorphonuclear lymphocytes. A diagnosis of pyogenic granuloma associated with a dental implant was made. In this case it was the result of an inappropriate choice of a healing cap, thus allowing an accumulation of dental plaque and sustained chronic inflammation of the peri-implant tissue. A conservative excision and replacement of the healing cap were sufficient for definitive treatment.

Cysts of the temporomandibular joint. Report of two cases.

Two patients with a cyst of the TMJ are presented. One had a synovial cyst, the other a ganglion cyst. The differential diagnosis of these lesions is discussed.

treatment of mandibular fractures with rigid osteosynthesis: Using the AO system

PURPOSE This study evaluated the results achieved in the surgical treatment of all mandibular fractures at two university centers using the 2.7 AO mandibular system. PATIENTS AND METHODS A total of 227 patients presenting with 180 single fractures and 47 with double fractures (274 osteosyntheses) were included in this prospective study. RESULTS During a mean follow-up of 27.5 months (minimum, 12 months), an overall complication rate of 7% was observed. No infection justified early removal of the osteosynthesis material. CONCLUSIONS The systematic use of the technique recommended by AO for treating mandibular fractures, performed by thoroughly experienced operators on a compliant population, results in a low rate of complications and an early return to normal function.

Deliberate, fixed extra-articular obstruction: Treatment of choice for subluxation and true recurrent dislocation of the temporomandibular joint

Temporomandibular dislocation and subluxation are two pathological situations both characterized by hypermobility of the condyle. We believe that when luxation is recurrent and when subluxation becomes painful or is accompanied by disc dysfunction, surgical intervention is indicated. We are impressed by Gosserez and Dautreys (1967) method of augmentation of the tubercle, or extra-articular obstruction, which is a modification of Leclerc and Girards (1943) original procedure. The advantages of this technique are described and results are based on a series of 38 patients.

Homologous cancellous bone grafts for large jaw defects caused by bone cysts

For more than 10 years homologous bone stored at -20 degrees C has been used to fill large bone cavities after cystectomy. This article outlines the principles of collecting, storing, and preserving the homograft, presents special aspects of the surgical technique, and reports long-term results.

Infiltrating intramuscular lipoma of the temporal muscle. A case report with molecular cytogenetic analysis

Intramuscular lipomas are uncommon benign mesenchymal tumors which infiltrate skeletal muscle and are exceedingly rare in the head and neck region. Because of the infiltrating nature of the lesion and a high propensity for recurrence, they are sometimes difficult to distinguish from well-differentiated liposarcomas (WDLS). We report, the first case of an infiltrating lipoma of the temporal muscle in a 62-year-old white man who presented with a slow growing mass in the left temporal region. The histopathological examination showed diffuse infiltration of the striated muscle fibers by mature adipocytes. There were no lipoblasts or cells with atypical nuclei as described in WDLS. We performed interphase fluorescence in situ hybridization (FISH) analyses using painting probes for chromosome 12 and a specific probe for the MDM2 gene and comparative genomic hybridization. The results did not identify MDM2 or 12q amplification and therefore confirmed the benign nature of the lesion.

Osteonecrosis of the jaw after treatment with bisphosphonates: is irreversible, so the focus must be on prevention.

New generation bisphosphonates such as zolendronic acid, pamidronate, and alendronic acid have various indications in medicine. Initially, their use was restricted to patients with metastatic bone malignancy secondary to breast cancer, lung cancer, prostate cancer, or multiple myeloma. Their benefit in these conditions led to wider application for other bone pathologies, such as osteoporosis and Pagets disease.1 Their main effect is to inhibit osteoclast activity; however, they also seem to have antiangiogenic effects, …

Intraoral venous malformation presenting with multiple phleboliths

Venous malformations are the most common of all vascular anomalies. Phleboliths are described as characteristic of such malformations; furthermore, when they are encountered in the major salivary glands, they must be differentiated from salivary calculi. We report a case of an intraoral venous malformation in the left retromolar area with multiple phleboliths.

A destructive calcium pyrophosphate dihydrate deposition disease of the temporomandibular joint.

A case of calcium pyrophosphate dihydrate (CPPD) crystal deposition arthropathy of the temporomandibular joint is reported. The patient presented a 10-year history of swelling and pain of the left preauricular region. Magnetic resonance imaging showed a calcified mass filling the joint space and destroying the roof of the joint. Radiographs showed chondrocalcinosis of other joints. The authors discuss the diagnosis of this arthropathy and the reason why the temporomandibular joint is more affected than the other joints in the patient reported.