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131.
132.
Becker S Schön R Gutwald R Otten JE Maier W Hentschel R Jüttner E Gellrich NC 《The British journal of oral & maxillofacial surgery》2007,45(4):326-327
Teratomas are benign tumors containing cells from ectodermal, mesodermal and endodermal layers. They occur in about 1 in every 4000 births and most commonly in the sacrococcygeal region, followed by the ovaries. Congenital epignathus teratomas are rare embryological neoplasms localised in the region of head and neck. An epignathus is found in approximately 1:35,000 to 1:200,000 live births. This accounts for 2-9% of all teratomas. Size and location of the neoplasm in the oronasopharynx is variable. Teratomas are partly undiagnosed at the time of birth. They may exist with an intracranial extension or as small polyps. Large epignathi can lead to difficult management during and after birth. The case of a newborn girl with a combination of an epignathus and a cleft palate is described. The epignathus presented as a huge mass extending out of the mouth of the infant girl. On the day of birth debulking of the extraoral portion of the tumor, followed by intraoral exstirpation, was performed. The results of the histologic examination indicated a congenital epignathus. Six months later a recurrence was found. 相似文献
133.
Cementifying fibromas are rare fibro-osseous tumours that are usually found in the jaws. We report a 10-year-old boy who presented with a mass in the frontal bone causing frontal bossing and proptosis. The preoperative diagnosis was not clear despite computed tomographic and magnetic resonance imaging. The lesion was resected completely and found to be a cementifying fibroma. It was reconstructed at the same operation and he made a good recovery with no sign of recurrence. 相似文献
134.
Kokubo Y Tsumita M Sakurai S Torizuka K Vult von Steyern P Fukushima S 《Journal of oral rehabilitation》2007,34(7):503-507
This study evaluated the fracture loads of three-unit all-ceramic bridges on implants; the core frameworks of the bridges were made of zirconium oxide. Three core framework designs were fabricated according to the design of the bars between the retainers: (i) straight, (ii) curved in the occlusal direction, or (iii) curved in the gingival direction. A static load was applied at the centre of the pontic, and the mean initial crack and final fracture loads were measured and compared. The core framework curved in the occlusal direction had the highest final fracture loads; there were significant differences (P < 0.05) in the mean final fracture load, whereas initial fracture load, which fractured of veneered porcelain, did not show significant differences among three designs. The all-ceramic bridges on the implants made with Procera zirconium core frameworks had high final fracture load. The core framework design that curved in the occlusal direction helped the framework withstand the occlusal load, which results in reliable prostheses, especially in the molar region. 相似文献
135.
Quantitative methylation analysis of resection margins and lymph nodes in oral squamous cell carcinoma 总被引:1,自引:1,他引:1
Shaw RJ Hall GL Woolgar JA Lowe D Rogers SN Field JK Liloglou T Risk JM 《The British journal of oral & maxillofacial surgery》2007,45(8):617-622
Resection is the preferred treatment for oral squamous cell carcinoma, and pathological staging of the resected specimen is crucial. The role of molecular biology in the diagnosis of minimal residual disease has not been fully investigated and may improve staging. Multiple adjacent specimens were taken from the tumour, the invasive front, the surgical margin, and the lymph nodes of 20 specimens from patients with oral cancer. Bisulphite-treated DNA from these specimens was assayed quantitatively with pyrosequencing methylation assays (PMA) of CpG islands within the gene promoters of the p16 and CYGB genes. Results were recorded with histopathological results, and compared with clinical outcome. Biological and technical replicates confirmed the reliability of the techniques. PMA upgraded 13 of the 20 surgical margins, 6 of which subsequently had a recurrent tumour. Not all of these recurrences were predicted and the effects of adjuvant treatment make firm conclusions difficult. 相似文献
136.
AIM: To compare the remineralisation effects of different child dentifrices on primary teeth. DESIGN: In vitro single-section technique and pH-cycling model. METHODS: Primary teeth were painted with nail varnish, leaving a 1 mm wide window before placing in demineralising solution for 96hr to produce artificial carious lesions 150-200 microm deep. Teeth were longitudinally cut into approximately 100-150 microm thick sections and assigned to three groups (n = 7). Sections in Group A were exposed to Perioe Children's Toothpaste (LG, Korea), Group B to Colgate Pokemon (Colgate-Palmolive, Thailand) and Group C to Vicco (Vicco Laboratories, India). Polarised light microscopy and microradiography was used to evaluate lesion depth, before and after 7 days pH cycle. RESULTS: Mean lesion depths in Groups A and C increased by 11% and 14% respectively, while Group B demonstrated a lesion reduction of 3%. Comparisons using ANOVA and Student-Newman-Keuls tests showed that Groups A and C were significantly different from Group B (p < 0.05), but there was no significant difference between Groups A and C. CONCLUSIONS: Based on the data obtained, Colgate Pokemon remineralised initial carious lesions. In addition, when compared to Colgate Pokemon, Perioe Children's Toothpaste failed to show 'healing' efficacy even though it is claimed to contain fluoride. 相似文献
137.
A clinician evaluates a tooth for its quality of health. Once accomplished an estimate of longevity and survival is estimated. With current knowledge about the survival and success of implants a decision is made as to whether to extract or to treat and maintain the tooth. Questions and doubts abound in the decision making process in regards to the prognosis of an individual tooth. Unfortunately in dentistry, as in all biologic sciences, there are no straightforward answers to questions. This article will attempt to review the literature in this area to aid the practitioner in the decision making process with regards to the compromised tooth. The article will focus on the single tooth or implant restoration. Other factors such as the strategic value of a tooth and financial limitations in relation to long-term prognosis will also be discussed. 相似文献
138.
This study was conducted to determine the fluoride intakes in 94 preschool children aged 3, 4 and 5 (n = 30, 30, 34, respectively) residing in Yokkaichi, Mie Prefecture (< 0.16 ppm F water supply). The parents duplicated all the diets that their children ingested on 3 separate days during a 1-year period. The acid-diffusible fluoride in the diet was isolated by the acid-diffusion technique and measured with a fluoride electrode. The mean daily fluoride intakes from diet alone by children aged 3, 4 and 5 were 0.30 mg (n = 29, SD 0.19), 0.28 mg (n = 30, SD 0.19) and 0.30 mg (n = 34, SD 0.19), respectively. The total estimated mean values from diet and dentifrice were 0.35 mg (n = 29, SD 0.22, range 0.13-1.00), 0.33 mg (n = 30, SD 0.19, range 0.13-0.86) and 0.39 mg (n = 34, SD 0.18, range 0.18-1.01), respectively. It was concluded that the mean (+/-SD) total fluoride from diet and dentifrice in 3- to 5-year-old Japanese children was 0.35 +/- 0.19 mg/day (0.021 +/- 0.012 mg/kg body weight). 相似文献
139.
140.
Natsume N Niimi T Furukawa H Kawai T Ogi N Suzuki Y Kawai T 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2001,91(2):157-161
There have been many reports on congenital anomalies associated with cleft lip and/or palate (CL/CLP) in Japan. However, these reports included data only on patients who came to hospitals; thus the real situation regarding these anomalies remains unclear. Therefore, we surveyed newborns at all delivery facilities in the central area of Japan for the presence of these anomalies, following their progress for 12 consecutive years; at the end of that time, questionnaires were collected and analyzed. In this article, we describe our results. 相似文献