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91.
Background: There is limited information regarding marginal bone‐level changes around immediately loaded implants placed with the osteotome technique. The aim of this case series is to prospectively evaluate the clinical and radiographic outcome of immediately loaded implants placed with the osteotome technique over a 12‐month period. Methods: Eighteen patients in need of oral prosthetic rehabilitation that included single implant placement in positions #4 to #13 and/or #20 to #29 participated in this prospective trial. A modified implant installation procedure with an under preparation of the implant bed using the osteotome technique and immediate loading of the implant was performed. Clinical examinations were performed at 2 weeks, 6 months, and 12 months of follow‐up. Radiographic examinations were performed at implant installation and at the 6‐ and 12‐month follow‐up visits. Results: One implant failed to integrate and was removed at 3 months after implant installation. Four of 20 implants had insertion torque value >35 Ncm. The mean marginal bone loss was ‐0.09 mm at the 6‐month and ‐0.19 mm at the 12‐month follow‐up visits. Conclusion: The present case series indicates that implants placed with the osteotome technique and immediately loaded did not demonstrate a high insertion torque and exhibited minimal marginal bone loss. 相似文献
92.
OBJECTIVES: The present study aimed at evaluating the marginal bone resorption and the peri-implant tissue conditions around Narrow-Neck ITI implants in the implant-prosthetic treatment of the agenesis of maxillary lateral incisors. MATERIAL AND METHODS: Thirty patients affected by monolateral or bilateral agenesis of the maxillary lateral incisors were selected. Thirty-four ITI-SLA Narrow Neck implants were inserted and loaded about 4 months after the surgical procedure. The final restorations were realized using Aureo Galvan Crowns veneered with feldspathic ceramics. The follow-up period ranged from 24 to 39 months. Both marginal bone resorption and soft tissue quality were evaluated. The data were statistically analysed using analysis of variance (ANOVA) for repeated measures, one-way ANOVA and Tukey's post hoc test (P=0.05). RESULTS: During the 24-39-month follow-up period, no implant showed either pain and sensitivity or mobility. After 39 months of functional loading, a cumulative survival rate of 97.06% and a cumulative success rate of 94.12% were calculated. CONCLUSIONS: In case of maxillary lateral incisor agenesis, the implant-prosthetic approach has proved to be a reliable and predictable treatment for both re-establishment of function and aesthetics. Satisfactory values of marginal bone resorption over time and optimal conditions of peri-implant tissue around Narrow-Neck ITI implants were found. 相似文献
93.
Nedir R Bischof M Vazquez L Szmukler-Moncler S Bernard JP 《Clinical oral implants research》2006,17(6):679-686
OBJECTIVE: The aim of the present pilot study was to evaluate: (1) the predictability of an osteotome sinus floor elevation procedure with ITI-SLA implants without placing a bone grafting material, and (2) the possibility to gain bone height without filling the created space with a bone grafting material. MATERIAL AND METHODS: Seventeen patients received 25 implants protruding in the sinus. Most implants (21/25) were 10 mm long, eight were inserted in type 2 bone, 12 in type 3 and five in type 4 bone. At implant placement, the mean residual bone height (RBH) under the maxillary sinus was 5.4+/-2.3 mm; it was 5.7+/-2.6 mm on the mesial side and 5.1+/-1.9 mm on the distal side. Nineteen implants had less than 6 mm of bone on at least one side and six implants had less than 6 mm on both sides. A healing period of 3-4 months was allowed before abutment tightening at 35 Ncm. The percentage of stable implants at abutment tightening and at the 1-year control was calculated. The endo-sinus bone gain and the crestal bone loss (CBL) at the mesial and distal sides were measured. RESULTS: Abutments were tightened after 3.1+/-0.4 months. All implants but one (96%) resisted the applied 35 Ncm torque. At the 1-year control, all implants were clinically stable and supported the definitive prosthesis. All showed endo-sinus bone gain; the mean gain was 2.5+/-1.2 mm. The mean CBL was 1.2+/-0.7 mm. Endo-sinus bone gain and RBH showed a strong negative correlation (r=-0.78 on the mesial side and -0.80 on the distal side). A good correlation (r=0.73) was found between implant penetration in the sinus and endo-sinus bone gain. CONCLUSION: Elevation of the sinus membrane alone without addition of bone grafting material can lead to bone formation beyond the original limits of the sinus floor. Despite a limited RBH at implant placement, a healing period of 3 months was sufficient to resist a torque of 35 N cm and to lead to a predictable implant function at the 1-year control. 相似文献
94.
Malo P de Araújo Nobre M Lopes A Moss SM Molina GJ 《Journal of the American Dental Association (1939)》2011,142(3):310-320
BackgroundImmediate-function implants have become an accepted alternative for fixed restoration protocols in edentulous mandibles on the basis of documented high success rates. The All-on-4 concept (Nobel Biocare, Göteborg, Sweden), a surgical and prosthetic protocol for immediate function involving the use of four implants to support a fixed prosthesis in patients with completely edentulous mandibles, represents one of these protocols. The authors conducted a study to document long-term follow-up of the All-on-4 concept.MethodsThis longitudinal study included 245 patients with a total of 980 immediate-function implants (four per patient), all placed in the anterior region, to support fixed full-arch mandibular prostheses. The inclusion criterion was having an edentulous mandible, or a mandible with hopeless teeth, in need of fixed implant restorations.ResultsA total of 21 implants failed in 13 patients, giving cumulative patient-related and implant-related success rates of 94.8 percent and 98.1 percent, respectively, at five years, and 93.8 percent and 94.8 percent, respectively, with up to 10 years of follow-up. The prostheses’ survival rate was 99.2 percent with up to 10 years of follow up.ConclusionsThe results support the conclusion that use of the All-on-4 immediate-function implant concept in completely edentulous mandibles is viable in the long term.Clinical ImplicationsHigh prosthesis survival rates can be achieved by the use of four implants to support a full-arch fixed prosthesis in the mandible. 相似文献
95.
目的:评价数字全景X片在测量非负荷期种植体周围牙槽骨吸收的应用情况。方法:观测、分析对比共26例病人50枚Camlog系统种植体的临床应用非负荷期间数字化X片和X线牙片上种植体周围牙槽骨吸收的情况。结果:50枚Carolog种植体植入后10天、两种X片骨吸收测量结果分别为0.65mm\0.81mm,两者之间无明显差异;第四个月(或六个月\下颌)分别为0.12\1mm\0.19mm,两者之间无明显差异。结论:本研究显示数字化X片在测量非负荷期种植体周围牙槽骨吸收的应用中有操作简单.重复性好、精确度高、变形可补偿等优点,有实际应用价值,值得推广。 相似文献
96.
A number of experimental data on biomimetic deposition CaP (BDCaP) coating implants have reported promising outcomes by histological evaluation. But little is investigated on the role of the BDCaP coating and osseointegration mechanism by interface shear strength. To make a direct biomechanical comparison between the BDCaP coating implants and the uncoated rough titanium implants (control), a well-established animal model for implants removal torque testing was employed in rabbits, using a self-matching experimental design. All implants had an identical cylindrical screw shape without any macroscopic retentive structure. After 2, 4, 6, 8 and 12 weeks of bone healing, removal torque testing was performed to evaluate the interfacial shear strength of each implant type. The torqued implants were sputter-coated with gold for morphology observation and observed with a field-emission electron microscopy. Results showed that the interfacial shear strength of the BDCaP coating implants was similar to that of the uncoated rough implants at 2 and 4 weeks of healing. The mean removal torque values of the BDCaP coating implants were lower than those of control implants (P < 0.05) after 6 weeks of healing. The removal torque values for both types of implants revealed similar mean values after 8 and 12 weeks of healing; there were no significant difference between the two types of implants (P > 0.05). It can be concluded that the BDCaP coating implants had no beneficial effect on the interfacial shear strength at early bone healing stage. 相似文献
97.
Cordioli G Mazzocco C Schepers E Brugnolo E Majzoub Z 《Clinical oral implants research》2001,12(3):270-278
This clinical study was undertaken to: 1) evaluate the use of bioactive glass Biogran combined with autogenous bone as grafting material for maxillary sinus augmentation with simultaneous implant placement using radiography and histology; and 2) document the short-term post-loading success of implants inserted in sinus cavities augmented with this material. Unilateral or bilateral sinus augmentation was performed in 12 patients with 3-5 mm of alveolar crestal bone height in the posterior maxilla prior to grafting. The sinuses were grafted with bioactive glass mixed in a 4:1 ratio with autogenous bone. Simultaneously, 2-3 threaded titanium implants were inserted into the augmented sinuses. Second stage surgery was carried out 9 to 12 months post implantation. At abutment connection, 10 core biopsy specimens were taken from different grafted sites and evaluated histologically. All 27 implants were clinically stable at second stage surgery. A mean increase in mineralized tissue height of 7.1 +/- 1.6 mm was evident when comparing the pre-surgical CT scans with those performed 9-12 months following the sinus augmentation procedure. Evaluation of the cores yielded a mean of 30.6 +/- 5.7% of bone tissue in the grafted sites. One implant failed during the prosthetic phase while the remaining 26 implants were stable 12 months post loading. This study suggests that Biogran/autogenous bone graft combination used in one-stage sinus augmentation yields sufficient quality and volume of mineralized tissue for predictable simultaneous implant placement in patients with 3-5 mm of bone height prior to grafting. 相似文献
98.
目的:评价下颌无牙颌种植固定修复早期负载的可行性和临床疗效。方法:14例下颌无牙颌病例共植入94颗ITISLA种植体,种植体植入后第6周完成固定修复。于植入当天、第4周、修复后1年行影像学检查,观察种植部位牙槽骨吸收情况。在植入即刻及第4周行共振频率分析。结果:种植体1年成功率为100%,修复体的1年成功率为100%。影像学检查示种植体周无低密度影;种植部位牙槽骨水平未见明显吸收,均位于种植体第一螺纹的冠方,从全景片测量得1年牙槽骨水平吸收为(0.3±0.94)mm。共振频率分析显示,植入即刻与第4周分别为69.54±4.29和63.14±5.57。结论:ITI SLA种植体固定修复下颌无牙颌早期负载是可行的。 相似文献
99.
The influence of periodontitis on the subgingival flora around implants in partially edentulous patients 总被引:2,自引:1,他引:2
The hypothesis that teeth act as reservoirs of micro‐organisms for the colonization of oral implants has recently been stated several times. The present study aimed at examining, in partially edentulous patients with severe periodontitis, whether pockets around teeth and implants harbored a comparable micro‐flora. In 6 patients (3 with refractory periodontitis and 3 with advanced chronic adult periodontitis), plaque samples were taken from a deep and shallow pocket around both teeth and implants for differential phase contrast microscopy and DNA probe analysis. The results showed important differences in the sub‐gingival flora between the 2 disease groups, as well as between deep and shallow pockets, around both implants and teeth. On the other hand, when pockets around teeth and implants with equal depths were compared a striking similarity was observed in the microbial composition. These observations confirm the hypothesis that pockets around teeth act as a reservoir and highlight the importance of periodontal health when oral implants are planned. 相似文献
100.
Aloufi F Bissada N Ficara A Faddoul F Al-Zahrani MS 《Clinical implant dentistry and related research》2009,11(1):37-40
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
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