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951.
A 32-year-old female patient was referred to an oral and maxillofacial surgeon with an asymptomatic swelling in the left mandibular premolar region. After extraction of these premolars and enucleation of the lesion histopathological examination confirmed the presence of a giant cell granuloma. This is a benign lesion and enucleation generally results in a permanent cure and is only recurrent in a few cases. Approximately 1 year after treatment, the patient was still free of recurrence and together with a prosthodontist, the appropriate rehabilitation of the resulting defect will be sought.  相似文献   
952.
Purpose: This retrospective study assessed the health of peri-implant tissues in patients with varying severity of chronic periodontitis.
Materials and Methods: Sixty-one subjects aged 44 to 70 years (median age 58 years) were recruited. Based on severity of periodontitis, 31 subjects were classified as having severe generalized chronic periodontitis, and the remaining 30 subjects had mild or no periodontitis. Social and medical histories were obtained from each patient. A comprehensive periodontal examination included: plaque index, gingival index, bleeding index, probing depth, clinical attachment level, and radiographic bone loss. Data were analyzed using Fisher's exact and chi-square tests for categorical variables, and t -test for continuous variables.
Results: There was a statistically significant greater loss of attachment ( p  < .05) around implants in the group with severe periodontitis compared to the no/mild periodontitis group.
Conclusion: Because of the greater loss of clinical attachment around implants placed in patients with generalized severe chronic periodontitis, close monitoring of these patients is suggested to prevent both development of peri-implantitis and recurrence of periodontal infection.  相似文献   
953.
AIMS: (i) To carry out meta-analyses to quantify the influence of the clinical factors on the efficacy of primary root canal treatment and (ii) to identify the best treatment protocol based on the current evidence. METHODOLOGY: The evidence for the effect of each clinical factor on the success rate (SR) of primary root canal treatment was gathered in three different ways: (i) intuitive synthesis of reported findings from individual studies; (ii) weighted pooled SR by each factor under investigation was estimated using random-effect meta-analysis; (iii) weighted effect of the factor under investigation on SR were estimated and expressed as odds ratio for the dichotomous outcomes (success or failure) using fixed- and random-effects meta-analysis. Statistical heterogeneity amongst the studies was assessed by Cochran's (Q) test. Potential sources of statistical heterogeneity were investigated by exploring clinical heterogeneity using meta-regression models which included study characteristics in the regression models. RESULTS: Out of the clinical factors investigated, pre-operative pulpal and periapical status were most frequently investigated, whilst the intra-operative factors were poorly studied in the 63 studies. Four factors were found to have a significant effect on the primary root canal treatment outcome, although the data heterogeneity was substantial, some of which could be explained by some of the study characteristics. CONCLUSIONS: Four conditions (pre-operative absence of periapical radiolucency, root filling with no voids, root filling extending to 2 mm within the radiographic apex and satisfactory coronal restoration) were found to improve the outcome of primary root canal treatment significantly. Root canal treatment should therefore aim at achieving and maintaining access to apical anatomy during chemo-mechanical debridement, obturating the canal with densely compacted material to the apical terminus without extrusion into the apical tissues and preventing re-infection with a good quality coronal restoration.  相似文献   
954.
We describe an unusual adverse reaction that was probably caused by taking ecstasy: the patient developed widespread oral and oropharyngeal mucosal oedema, which was triggered after he had taken ecstasy and alcohol. The reaction to this could have been fatal.  相似文献   
955.
A border outline for mandibular implant-retained dentures is described. The lingual extension of the impression is greatly reduced compared with a conventional mandibular denture. Because of the implant attachment, the shortened border is more comfortable and does not compromise denture retention. Improper implant position is also discussed with respect to denture extension.  相似文献   
956.
Phosphoric acid etching of dentin is critically reexamined in view of current adhesive resin development. Research and clinical experience both suggest that "total etch," the simultaneous etching of dentin and enamel, is a rational protocol with many modern adhesive resins.  相似文献   
957.
958.
Treatment of a patient who requires a mandibular complete prosthesis opposing a natural maxillary dentition presents a unique set of problems for the clinician. Proper prosthodontic care can not only result in a functional and comfortable prosthesis, but may reduce the rate of resorption of the remaining mandibular ridge.  相似文献   
959.
Recent studies have shown that maxillary molar teeth with furcation involvement can be retained for many years in a state of health. Removal of one or more roots may be required to create a morphology that can be maintained. Proper treatment planning is essential for long-term success. The indications for root amputation and surgical technique are described. Esthetic restorative procedures are illustrated.  相似文献   
960.
Punch biopsies were obtained from the buccal gingiva of the lower third molars. Thin nerve fibres, immunoreactive for calcitonin gene-related peptide (CGRP) or substance P (SP), with possible sensory function, were found in the propria often close to the epithelium, sometimes even penetrating into the basal layers. gamma-Melanocyte stimulating hormone (gamma-MSH)-like immunoreactivity was found in sparsely distributed single cells (except in one specimen containing a dense infiltration), resembling neutrophilic granulocytes of the propria. gamma-MSH was present in several single smooth axons and in thick axon bundles of the propria. Surrounding the blood vessels, neuropeptide Y (NPY), tyrosine hydroxylase (TH), vasoactive intestinal polypeptide (VIP) and peptide histidine isoleucine amide (PHI) immunoreactive nerve fibres were observed. NPY and TH-positive fibres probably represent sympathetic nerve terminals and VIP/PHI-immunoreactive ones may have a parasympathetic function. Papillae of the propria contained VIP-positive fibres not obviously related to blood vessels. The distribution in papillae of PHI-like immunoreactivity was similar but the PHI-positive reaction was also present in a few cells of the propria, especially near blood vessels. Somatostatin (SOM)-positive reaction occurred in a few dendritic-type cells near or in the epithelium and single nerve fibres close to the epithelium. Several thick axon bundles of the propria contained neurofilament (NF)-immunoreactive material. Some thin NF-fibres were found in the papillae and some seemed to penetrate into the epithelium. No galanin, methionine-enkephalin, parathyroid hormone or proctolin immunoreactive material was found. The rather rich content of several neuropeptides in human attached gingiva, as well as other neurochemical markers, is probably associated with sensory and autonomic functions.  相似文献   
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