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991.
OBJECTIVES: To report the modifications and complications of the Furlow palatoplasty for two-stage closure of the palate. PATIENTS AND METHODS: Prospective study of a consecutive series of 45 primary closures of the soft palate portion of clefts extending into the hard palate; mean (S.D.) age at repair 12 (2) months; median follow-up 4 years 4 months (range 2 months to 9 years). The hard palatal part of the cleft was closed in 18 patients at the mean age of 3 years 11 months. RESULTS: The main modifications that we made were the use of quilting sutures, lateral V-Y closures, and fibrin glue application, and the omission of lateral releasing incisions. Patients stayed in hospital for a median of 4 days (range 3-8 days). Two patients had postoperative partial obstruction of the airway and were given steroids. In six patients, a smaller portion of the oral layer of the wound broke down; it healed by secondary intention in five, but resulted in partial dehiscence in one. There were no oronasal fistulas in the 18 patients who had delayed closure of the hard palate part of the cleft. Secondary pharyngoplasty was not necessary in any patient. CONCLUSION: Furlow's technique has been modified for use in the two-stage closure of complete cleft palates (with or without cleft lip or alveolus) with an acceptable rate of complications.  相似文献   
992.
STATEMENT OF PROBLEM: Viscoelastic behavior can influence the fracture properties of glass ionomers, which is of clinical relevance. Glass-ionomer cements can display viscoelastic behavior, defined as having displacement rate- or strain rate-dependent mechanical properties. Understanding and describing the viscoelastic behavior of glass ionomers is important to understanding their clinical behavior. PURPOSE: The purpose of this study was to evaluate the viscoelastic behavior of 6 glass-ionomer cements and determine whether there was a correlation to fracture toughness. MATERIAL AND METHODS: Three conventional glass-ionomer cements (alpha-Silver, alpha-Fil, and Ketac-Molar) and 3 resin-modified glass-ionomer cements (Vitremer, Fuji II LC, and Photac-Fil Quick) were evaluated using measurements of compressive strength (CS), flexural strength (FS), and diametral tensile strength (DTS) at displacement rates of 0.5, 1.0, 1.5, and 2.0 mm/min. The CS and DTS specimens were cured in glass tubes and cut to 4 x 6-mm and 4 x 2-mm disk-shaped specimens, respectively. The FS specimens were cured in bar molds (2 x 2 x 15 mm). The fracture toughness (FT) specimens were cured in a minicompact mold to obtain precracked specimens. The mechanical testing results were compared statistically using generalized linear model/analysis of covariance and the Ryan-Einot-Gabriel-Welsch multiple range test at the alpha=.05 level. RESULTS: For all 3 mechanical properties, there was a displacement-rate dependence on the mechanical property. However, there were no differences in the displacement-rate dependence based on the type of material-conventional glass ionomer or resin-modified glass ionomer-for any of the mechanical properties. Only for FS test was there a significant difference based on the brand of material. There was no statistical difference in FT among the glass-ionomer cements tested, although the resin-modified glass ionomers tended to display higher FT. CONCLUSION: A larger sample size and a much wider range of crosshead speeds are necessary to support a correlation between viscoelastic behavior and FT.  相似文献   
993.
Evaluation of alveolar bone grafting: a survey of ACPA teams.   总被引:5,自引:0,他引:5  
OBJECTIVE: To evaluate the management of alveolar clefts by cleft palate and craniofacial teams in North America. DESIGN: An anonymous survey was mailed to 240 American Cleft Palate- Craniofacial Association teams across North America regarding alveolar bone grafting. The questionnaire included multiple questions about each team's approach to alveolar bone grafting and options for the missing tooth. RESULTS: Consensus was achieved in three areas: 90% of centers performed secondary alveolar bone grafting, 78% performed grafting between ages 6 and 9 years, and iliac crest donor site was the most popular site (83%). There was no consensus with respect to dental criteria for the timing of grafting, follow-up x-rays, or the use of a grading system for evaluating results. In addition, there was no consensus on the management of the missing tooth. CONCLUSION: There is wide acceptance of secondary bone grafting and there is a consensus for the age of grafting (6 to 9 years) and donor site (iliac crest). The disturbing finding was the lack of postoperative x-ray evaluation of the results. With so much variability in management, the use of a routine, standardized scale to measure postoperative results would allow for better outcome studies in alveolar bone grafting.  相似文献   
994.
Seventeen patients, who received an iliac crest onlay bone graft augmentation to their severely atrophic mandible with simultaneous placement of two endosteal implants by a modified surgical approach, were studied retrospectively. Follow-up ranged from 0.5 to 7.9 years after implant loading with an average follow-up of 4.3 years. Frequency of wound dehiscences and other postoperative complications, the extend of resorption of the initial graft, and the implant success rate were assessed. Two patients, who had a previous history of preprosthetic and implantological procedures at the surgical site, developed a serious wound dehiscence with loss of two implants in one patient and need for antibiotic treatment and sequestrectomy in the other patient. One implant was lost in two other patients with a negative surgical history, resulting in an implant success rate of 88.2%. The average resorption at the last follow up visit was 15% of the initial graft. Damage of the mental nerve was seen in 14.7% of nerves. Our preliminary data indicate that the procedure presented provides a reliable and predictable method for the construction of an implant-bearing overdenture in patients with a severely atrophic mandible. This one-step procedure can not be recommended for patients with a history of surgery in the anterior mandible.  相似文献   
995.
PURPOSE: The aim of this study was to describe the revascularization process of autogenous bone block grafts placed with or without an expanded polytetrafluoroethylene (e-PTFE) membrane. MATERIALS AND METHODS: Thirty Wistar male rats had their mandibles augmented by either an autogenous bone block graft (group A) or an autogenous bone block graft covered with an e-PTFE membrane (group B). The animals were sacrificed by perfusion at baseline, 3, 7, 14, and 21 days after surgery. RESULTS: After 3 days, the presence of vascular sprouts derived from the recipient bed was observed in group A; more discrete sprouts were also observed in group B. After 7 days, revascularization continued, with vessels derived from both the recipient bed and the surrounding connective tissue in group A but only from the recipient bed in group B. At 14 days, group A showed penetration of vessels at the periphery of the graft; the vessels reached varying distances inside it. In group B, revascularization of the graft occurred mainly near its perforation, its borders, and at the recipient bed-graft interface. After 21 days, graft vascular penetration could be observed throughout the extent of the graft in group A but only approximately halfway through the graft in group B. DISCUSSION: The results emphasized the importance of the vascular network and of the revascularization process of the autogenous bone graft in new bone formation. Early vascular penetration and nutrition of the graft are key factors in its integration with the recipient bed. CONCLUSIONS: Revascularization of the bone graft occurred in both A and B. However, vascular sprouts originated only from the recipient bed in group A, while in group B the graft was penetrated by vessels from both the recipient bed and the surrounding connective tissue. The revascularization took place more promptly and was more intense and extensive in group A than in group B for all periods.  相似文献   
996.
Despite the introduction of highly active antiretroviral therapy (HAART), diffuse large B-cell lymphoma (DLBCL) remains a common malignancy in human immunodeficiency virus (HIV)-infected patients, especially the plasmablastic variant. About 50% of lymphomas in HIV patients are extranodal and half of them occur in the head and neck area. The main oral symptoms are pain, swelling, numbness and tooth mobility. We report the case of a 52-year-old patient with a known HIV infection and fracture of the angular region of the mandible. The fracture did not unite following open reduction and osteosynthesis. A biopsy performed at the time of revision revealed the diagnosis of a primary lymphoma in the mandible. After chemotherapy had induced complete remission of the lymphoma and autogenous iliac crest bone grafting had been performed the fracture united. Primary lymphoma in the mandible is a disease that presents with a nonspecific radiological appearance which may mimic osteomyelitis or periodontal pathology. A rapid and accurate diagnosis is critical for the appropriate treatment. In our experience HIV-positive patients with mandibular fracture should be treated according to the guidelines established for HIV-negative patients. However, risky compromises such as intraoral approach or hazardous fracture fixation should be avoided.  相似文献   
997.
Hernia formation following harvest of bicortical iliac crest bone occurs infrequently as a late complication and may lead to chronic pain at the donor site and rarely to obstruction and strangulation of bowel. We describe the use of a custom-made titanium plate used to reconstruct the iliac donor site following harvest of a DCIA composite free flap. A pre-operative 3D CT and stereolithography model of the ilium are used to fabricate a titanium plate of the desired shape and size. This plate is used to reconstruct the donor site defect at the time of primary surgery. This technique may reduce late complications following DCIA composite free flap harvest.  相似文献   
998.
The long spring-loaded distractor arms of maxillary distraction devices can cause pain and ulceration of the upper lip. We describe a simple method to relieve the tension and discomfort on the soft tissues using Silastic tubing.  相似文献   
999.
A bstract — The impact resistance of a polysulphone denture base polymer has been determined, and for comparison the impact resistance was also determined of a linear poly(methyl methacrylate) and four rubber-modified methacrylate denture base polymers. When tested under mouth conditions the polysulphone had an impact resistance more than four times as high as the poly(methyl methacrylate) and about twice as high as the most impact resistant rubber-modified methacrylate. Unlike some of the other materials tested, the polysulphone did not suffer a reduction in impact resistance on extended ageing under mouth conditions.  相似文献   
1000.
The purpose of this study was to survey the prevalence of streptococcal species, especially Streptococcus anginosus (which has been reported to be associated with cancer in the upper digestive tract), Streptococcus constellatus, and Streptococcus intermedius in the saliva of different age groups. A sequence analysis of 16S rDNA was performed and DNA quantified using real‐time polymerase chain reaction. The S. anginosus level increased with age, whereas the levels of S. constellatus and S. intermedius did not change. Streptococcus mitis was the predominant species in the saliva of all the age groups but, unlike the S. anginosus, the proportion of S. mitis in the salivary bacteria decreased with age. The increase in S. anginosus with age should be carefully monitored because of its association with diseases, including cancer.  相似文献   
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