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71.
目的评价釉基质蛋白(Emdogain)治疗牙周骨下袋的临床疗效。方法随机选择8名牙周基础治疗4周后的2 4 (4 8个位点)处骨下袋,试验组13处(2 6位点)进行翻瓣加Emdogain植入,另外11(2 2位点)处行改良Widman’s翻瓣术加以对照。术后6、12月复查,比较两组临床疗效。结果Emdogain组术前的探诊探度、附着丧失和出血指数分别为6 .3mm、7.0mm和2 .6 ;术后6月时分别为2 .9mm、3.6mm和1.4 ;术后12月为2 .8mm、3.5mm和1.2。改良Widman’s翻瓣组术前的探诊深度、附着丧失和出血指数分别为6 .2mm、6 .7mm和2 .8;术后6月时分别为3.9mm、4 .9mm和1.8;术后12月为3.8mm、4 .8mm和1.6。术后Emdogain和改良Widman’s翻瓣组的探诊深度、附着丧失和出血指数均比术前明显减少(P <0 .0 0 1) ,但Emdogain组上述指标明显低于改良Widman’s翻瓣组(P <0 .0 1)。结论翻瓣+釉基质蛋白(Emdogain)和改良Widman’s翻瓣术明显改善骨下袋患牙的临床指标,而前者的临床疗效优于后者。  相似文献   
72.
可流动复合树脂充填楔状缺损的体外微渗漏研究   总被引:2,自引:1,他引:2  
陈晨  吴友农  吴红霞 《口腔医学》2005,25(2):100-102
目的 研究可流动复合树脂充填楔状缺损离体牙模型的边缘微渗漏情况。方法 选择因正畸拔除的上颌前磨牙2 4个,于颊侧颈部釉牙骨质界处备V型洞后,随机分为3组,分别采用Aelieteflo可流动复合树脂,DyractAP复合体,GICTYPEII化学固化玻璃离子进行充填。经力循环、热循环后,2 %亚甲基蓝染色2 4h ,将每个牙齿自颊舌向沿长轴连续切3片。体视显微镜放大4 0倍观察充填体边缘染液渗漏情况。结果 3组间充填体微渗率差异有显著性(P <0 .0 0 1) ,以Aelieteflo材料的边缘微渗率最低(P <0 .0 5 )。3组牙合侧壁与龈侧壁微渗率间差异无显著性(P =0 .2 6 3)。结论 可流动复合树脂用于楔状缺损充填可以获得较好的边缘封闭性。  相似文献   
73.
MDIC种植体颧骨种植在全上颌骨缺损功能重建中的应用   总被引:5,自引:1,他引:5  
目的 :研究MDIC种植体在颧骨种植重建全上颌骨缺损的方法及临床效果。方法 :6例肿瘤治疗后全上颌骨缺损的患者 ,应用MDIC种植体在颧骨种植 ,通过种植修复体进行上颌骨缺损功能重建。结果 :重建后患者的面形明显改善 ,修复体固位良好 ,发音及咀嚼功能得到很好的恢复 ,植入的种植体可以实现骨结合并完成种植修复 ,行使功能。结论 :此方法可以实现全上颌骨缺损的功能重建。  相似文献   
74.
AIM: The aim of this controlled, parallel design clinical study was to compare the healing of intrabony periodontal defects following treatment with access flap surgery with and without debridement with an Er:YAG laser. METHODS: Twenty-three patients each of whom exhibited one deep intrabony defect were randomly treated with either access flap surgery followed by root surface and defect debridement using an Er:YAG laser (KEY3) (160 mJ, 10 Hz) (test), or with access flap surgery followed by root surface and defect debridement using hand and ultrasonic instruments (control). The following clinical parameters were recorded at baseline and at 6 months: plaque index; gingival index; bleeding on probing; probing depth (PD); gingival recession; and clinical attachment level (CAL). The primary outcome variable was CAL. No statistically significant differences between the groups were found at baseline. RESULTS: No serious adverse events were observed after any of the treatments. The results have shown that in the test group the PD decreased from 7.8+/-1.3 to 4.1+/-1.3 mm (p<0.001) and the CAL changed from 9.8+/-2.9 to 7.2+/-2.5 mm (p<0.001). In the control group the PD decreased from 7.8+/-0.8 to 4.6+/-1.6 mm (p<0.001) and the CAL changed from 9.2+/-1.2 to 7.7+/-1.6 mm (p<0.01). The test group displayed a higher tendency for CAL gain, although this tendency did not prove to be statistically significant. CONCLUSION: Within the limits of the present study, it can be concluded that: (i) at 6 months following treatment both therapies led to significant improvements of the investigated clinical parameters, and (ii) an Er:YAG laser may represent a suitable alternative for defect and root surface debridement in conjunction with periodontal surgery.  相似文献   
75.
Low intensity lasers have been used by clinicians to improve healing and reduce pain in humans. Lasing also results in new bone formation around hydroxyapatite implants and a significant increase in the total bone area. However, the exact mechanism of cell biostimulation by laser is still unclear. This study biochemically assessed the effects of low intensity laser (Gallium-Arsenide) using 4 and 22.4 mW cm(-2) power density on the bone healing process after surgically creating bony cavities in rat mandibles. Rats (n = 24) were divided into two groups each treated with specific energy, 4 or 22.4 mW cm(-2), for 3 min each day post-surgery. Surgical cavities were created on both sides of the mandible: the left served as an untreated control, the right was treated with laser. All rats were sacrificed after 1, 2 and 4 weeks of treatment. In the newly formed callus, accumulation of radiocalcium and alkaline phosphatase activity was measured to indicate osteogenic activity. One-way anova with repeated measures showed that the low intensity laser using 4 mW cm(-2) power density significantly increased radiocalcium accumulation from 2 weeks post-surgery, whereas 22.4 mW cm(-2) had no effect. No changes were noted in the activity of alkaline phosphatase with the laser treatment. These results suggest that laser therapy of low power density is effective on the bone healing process in artificially created osseous cavities by affecting calcium transport during new bone formation.  相似文献   
76.
OBJECTIVES: The purpose of the present parallel-design, controlled clinical trial was to evaluate the treatment outcome of periodontal furcation defects following flap debridement surgery (FDS) procedure in cigarette smokers compared to non-smokers. MATERIALS AND METHODS: After initial therapy, 31 systemically healthy subjects with moderate to advanced periodontitis, who presented at least one Class I or II molar furcation defect, were selected. Nineteen patients (mean age: 40.3 years, 15 males) were smokers (>or=10 cigarettes/day) and 12 patients (mean age: 44.8 years, 3 males) were non-smokers. Full-mouth plaque score (FMPS) and full-mouth bleeding score (FMBS), probing pocket depth (PPD), vertical clinical attachment level (v-CAL), and horizontal clinical attachment level (h-CAL) were assessed immediately before and 6 months following surgery. RESULTS: Overall, statistically significant v-CAL gain was observed in smokers (1.0 +/- 1.3 mm) and non-smokers (1.3+/-1.1 mm), the difference between groups being statistically significant (p=0.0003). In proximal furcation defects, v-CAL gain amounted to 2.3+/-0.7 mm in non-smokers as compared to 1.0+/-1.1 mm in smokers (p=0.0013). At 6 months postsurgery, non-smokers presented a greater h-CAL gain (1.3+/-1.1 mm) than smokers (0.6+/-1.0 mm), with a statistically significant difference between groups (p=0.0089). This trend was confirmed in both facial/lingual (1.4+/-1.0 versus 0.8+/-0.8 mm) and proximal furcation defects (1.2+/-1.3 versus 0.5+/-1.2 mm). The proportion of Class II furcations showing improvement to postsurgery Class I was 27.6% in smokers and 38.5% in non-smokers. After 6 months, 3.4% of presurgery Class I furcation defects in smokers showed complete closure, as compared to 27.8% in non-smokers. CONCLUSIONS: The results of the present study indicated that (1) FDS produced clinically and statistically significant PPD reduction, v-CAL gain, and h-CAL gain in Class I/II molar furcation defects, and (2) cigarette smokers exhibited a less favorable healing outcome following surgery in terms of both v-CAL and h-CAL gain.  相似文献   
77.
Abstract –  The aim of this study was to investigate the long-term effects of the use of human cadaveric solvent-dehydrated bone graft and duramater as a barrier membrane for the treatment of oroantral communication. Standard oroantral osseous defects were created in five minipigs. Subjects received cancellous bone graft in the form of block or microchips, duramater or a combination of bone and membrane. Uneventful healing was achieved in all of the subjects, clinically including the control site which did not receive any material. The operated bone segments were evaluated both by radiological and histological examinations after 6 months. Radiological evaluation was carried out using bone density analysis software and histological evaluation made by light microscopy. Radiological and histological results revealed that bone grafting of oroantral osseous defects improved the bone quality. However, application of duramater did not change this activity, both alone or combined with bone grafts. Within the limits of this experimental study, although solvent-dehydrated bone grafts were found superior and could be applied for the healing of osseous oroantral defects, resorbable membranes did not contribute to this process.  相似文献   
78.
AIM: The purpose of the present study was to investigate the effectiveness of a regenerative procedure based on supra-crestal soft tissue preservation in association with combined autogenous bone (AB) graft/enamel matrix derivative (EMD) application in the treatment of deep periodontal intra-osseous defects. METHODS: Thirteen consecutively treated patients, seven females and six males, aged 30-65 years, three smokers, were included. A total of 15 deep, one- to two-wall intra-osseous defects were selected. Immediately before surgery and 6 months after surgery, pocket probing depth (PPD), clinical attachment level (CAL), and gingival recession (REC) were recorded. RESULTS: PPD amounted to 9.4+/-1.8 mm before surgery, and decreased to 4.7+/-1.2 mm post-surgery (p<0.0000). CAL varied from 10.5+/-2.0 mm pre-surgery to 6.2+/-1.7 mm post-surgery (p<0.0000), with CAL gain averaging 4.3+/-1.4 mm. Fourteen (93.3%) defects presented CAL gain >/=3 mm. REC change was 0.4+/-0.7 mm. CONCLUSIONS: Results from the present study indicated that a regenerative procedure based on supra-crestal soft tissue preservation and combined AB/EMD treatment leads to a clinically and statistically significant improvement of soft tissue conditions of deep periodontal intra-osseous defects.  相似文献   
79.
The aim of this controlled retrospective study was to evaluate the influence of an IL-1 gene polymorphism on the clinical and radiographic healing outcomes of GTR therapy. The study included 47 adult periodontitis patients with 94 deep intrabony defects treated by GTR using different membrane materials. The following clinical parameters were recorded at baseline and 12 months after surgery: papillary bleeding index (PBI), gingival recession (REC), probing pocket depth (PPD), clinical attachment level (CAL), and the vertical relative attachment gain (V-rAG). Bone changes in the defect regions due to GTR therapy were quantitatively evaluated using digital subtraction radiography (DSR). Polymorphisms of the IL-1A gene at position - 889 and of the IL-1B gene at position + 3953 were analyzed by PCR. Statistical analysis was performed using the Mann-Whitney-U and the Wilcoxon-Signed-Rank tests (alpha = 0.05). The study comprised 19 IL-1 genotype positive (IL-1 +) patients and 28 IL-1 genotype negative (IL-1 -) patients. Twelve months after GTR therapy, both patient groups revealed statistically significant PPD reductions and CAL gain [median (25/75% percentiles)]: Delta PPD [IL-1 + : 4.0 (2.5/5.0) mm; IL-1-: 3.8 (3.0/4.9) mm], Delta CAL [IL-1 + : 3.5 (3.0/4.8) mm; IL-1 -: 3.0 (1, 2/4, 5) mm]. V-rAG amounted to 60.0 (47.7/78.6)% in IL-1 + patients and 53.1 (43.4/81.9)% in IL-1 - patients. Both patient groups showed significant bone density gain in 40% (IL-1 +) and 43.6% (IL-1 -) of the initial defect area due to GTR. Neither the clinical nor the radiographic healing parameters revealed any statistically significant differences in the GTR healing outcome between IL-1 + and IL-1 - patients. In conclusion, these 12-month findings indicate that the IL-1 gene polymorphism has no influence on the clinical and radiographic regeneration results following GTR therapy.  相似文献   
80.
Sixty-four sets of human teeth were collected with the aim of evaluating the role of trauma from occlusion in the etiology of destructive periodontal disease. Before the jaws were taken out, a careful bite analysis was carried out. After fixation of the jaws, impressions were taken and plaster of Paris models were made. Finally, a set of 14 radiographs were taken. On the basis of the "clinical" records postmortem, the study models and the radiographs, the jaws were sectioned. Only mesio-distal sections were included in the present analysis. The total number of interdental spaces examined was 106. The following observations were made: 1. Before any loss of periodontal fiber attachment has taken place, the configuration of the interdental septum is entirely dependent on the location of the cemento-enamel junction (CEJ) of the two neighboring teeth. The alveolar crest does not approach the apical border of the junctional epithelium closer than about 1 mm. Thus, if the CEJ is located at different levels on two neighboring teeth, the marginal termination of the interdental septum will be oblique, forming an acute angle with the "lowest" tooth. 2. Loss of periodontal fiber attachment could invariably be related to the apical growth of subgingival plaque, and downgrowth of plaque was always associated with an inflammatory process which involved lysis of the attachment fibers within a distance varying between 0.2 and 1.8 mm from the apical border of the plaque. Subsequently, the JE proliferated down to cover the denuded root surface. 3. Reduction in height of the alveolar crest could also be related to the downgrowth of plaque. The distance from plaque to bone was never found to be less than 0.5 mm and never more than 2.7 mm. The configuration of the interdental septum always seemed to be determined by the level of the plaque on the two neighboring tooth surfaces. Thus, if the plaque had reached the same level on both sides, the crest of the interdental septum assumed a horizontal outline; if plaque had proliferated down to different levels, the crest of the interdental septum was oblique and an angular defect hereby established. 4. In the present material no evidence was found to indicate that functional (traumatic) forces can act as a co-factor in the causation of angular defects. In fact, such defects were found equally often adjacent to "nontraumatized" as to "traumatized" teeth. 5. Infrabony pockets were invariably associated with downgrowth of subgingival plaque.  相似文献   
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