Ken Miyamoto

Lobular capillary hemangioma of the oral mucosa: clinicopathological study of 43 cases with a special reference to immunohistochemical characterization of the vascular elements.

Clinical and histopathological features were investigated in 43 cases of oral lobular capillary hemangiomas (LCH) with a special reference to characteristics of the vascular elements. The lesions affected females more than males by a ratio of 1:1.5. Average age of the patients was 52.7 years. The lesions involved the gingiva (n = 15), the tongue (n = 13), the labial mucosa (n = 10) and other sites. The lesions appeared usually as a pedunculated mass with ulceration; size of the lesions was up to 15 mm. Histologically, a lobular area and an ulcerative area were distinguished. The density of vessels was about 1045/mm2 and 160/mm2 in the lobular and ulcerative areas, respectively. The average diameter of the vascular lumen was 9.1   5.6 mm (range: 2.8–42.0 mm) and 18.8  20.9 mm (range: 5.6–139.7 mm) in the lobular and ulcerative areas, respectively. In the lobular area, most of the vessels had an inner layer of endothelial cells showing positive reaction for von Willebrand factor (vWF) and CD34, as well as an outer layer of mesenchymal cells showing positive reaction for alpha‐smooth muscle actin (ASMA). However, in the ulcerative area, there was a variety of types of vessels consisting of various proportions of both endothelial and ASMA‐positive perivascular mesenchymal cells. These results indicate that most of the vascular elements in the lobular area resemble more pericapillary microvascular segments than they do capillaries. Thus, the authors propose the term ‘lobular pericapillary hemangioma’ to represent this type of lesion.

Effects of a single arthrocentesis and a COX-2 inhibitor on disorders of temporomandibular joints: A preliminary clinical study

Our aim was to examine the short-term effect of combined treatment with single arthrocentesis and a COX-2 inhibitor on 26 patients with severe symptoms of temporomandibular joint (TMJ) disorders. The severity of the disorders was graded according to the degree of restriction of mouth opening and pain score on a visual analogue scale. Synovial fluid was collected from the superior joint space of the affected TMJ, and arthrocentesis was done with isotonic saline, 200ml. Subsequently, etodolac, 400mg/day, was given for 2 weeks. At 14 days, patients were re-examined and further specimens of synovial fluid were collected. Patients generally lost their symptoms and the severity of the disorders improved significantly (P<0.01). The concentrations of total protein and albumin in synovial fluid decreased with no statistical significance. However, the concentration of matrix metalloproteinase-3 and its ratios to total protein and albumin did decrease significantly (P<0.05). Our results suggest that a larger controlled study is necessary to clarify the contributory effect of arthrocentesis and etodolac for patients with severe symptoms of TMJ disorders.

Biochemical Aspects of the Pathogenesis of Temporomandibular Joint Disorders

Abstract Various molecular and inflammatory mediators, and matrix metabolites have been reported in the synovial fluid of patients with temporomandibular joint disorders. Additionally oxidative stress and the accumulation of free radicals may lead to tissue damage in all tissues, including the temporomandibular joint. These molecular events can trigger the degradation of collagen, hyaluronic acid, and proteoglycans, leading to the development of articular pathology. In this paper, the literature is reveiwed with an emphasis on synovial fluid, and the scientific evidence categorised to theoretically consider the aetiology and pathology of temporomandiblar joint disorders.