ITI种植体支持修复的临床研究

目的：评价非埋藏式ITI种植体修复牙例缺失的临床效果。方法：68例牙列缺失的患者，种植144颗ITI种植体。上颌种植牙于植牙后4～6个月行上部结构修复，下颌种植体于植牙后2～3个月行上部结构修复，种植后及义齿修复后的临床观察期为1～3年。结果：种植成功率为99．3％，义齿修复后行使功能的成功率为100％，有2例患者出现套冠脱落，未出现上部结构松动和折断现象。结论：非埋藏式种植体(ITI)修复牙例缺失有很高的成功率和良好的修复效果。     

下颌种植覆盖义齿附着体临床与力学研究

下颌种植覆盖义齿由种植体和上部结构组成。附着体是连接上部结构和种植体的固位装置。本文从（1）义齿的固位和稳定。（2）种植成功率，（3）患者满意度，（4）力学分析四个方面对下颌种植覆盖义齿的常用附着体加以综述。     

非埋藏式种植体支持的单个牙种植体效果评价

目的 评价非埋藏式种植体（ITI）在单个牙缺失种植修复中的效果。方法 65例共104颗单个牙缺失病例，采用ITI种植体种植修复，并进行定期随访观察。结果 种植后愈合期无1例种植体脱落，1a成功率与100％，5a成功率为99．1％，修复并发症主要是固位螺丝松动和八角基台折断。结论 非埋藏式种植在单个牙缺失的种植修复中有很高的成功率。     

球帽附着体种植覆盖义齿修复牙槽嵴重度萎缩无牙下颌

目的：总结分析BEGO种植体系统球帽附着体固位覆盖义齿,修复重度牙槽骨萎缩无牙下颌的临床应用与效果。方法：对重度牙槽骨萎缩、普通义齿固位极度不良的7例下颌无牙颌患者,在下颌骨前牙区植入2-3枚BEG0柱形螺旋种植体,共植入种植体17枚,后期采用球基台作球帽附着体固位覆盖义齿修复,定期复诊观察评价种植和覆盖义齿修复效果。结果：全部17枚种植体均顺利一期愈合,愈合周期平均3个月,球帽附着体覆盖义齿修复后经6-12个月观察,义齿稳定、咀嚼功能恢复理想,容貌改善明显,患者满意。结论：种植体支持球帽附着体固位覆盖义齿修复牙槽骨重度萎缩无牙下颌,可有效恢复咀嚼功能,改善患者容貌,提高患者生活质量,同时球帽附着体修复,简单经济,易于保持口腔清洁,可以推广。     

杆-卡结构种植覆盖义齿修复

本文对5例无牙颌患者，6副种植体支持的杆-卡结构种植覆盖义齿作2年的追踪观察资料作了总结。种植体为覆盖义齿提供了满意的支持。固位和稳定作用，增进了咀嚼功能的发挥。未见种植体松动和牙槽骨严重吸收。正确拟订治疗计划，术后戴用过渡性修复体，杆卡符合一定力学要求，正确处理义齿关系等均促成种植体的高成功率（100％）。修复后的定期检查，维护修复体、种植体及杆的清洁，对确保修复的成功具有重要意义。杆卡结构种植覆盖义齿修复牙槽嵴严重吸收的无牙颌是可行的。     

种植覆盖义齿修复牙槽骨严重萎缩的无牙下颌

目的：本文报告用Replace种植体或MIC种植体支持、用夹子和杆固定种植覆盖义齿修复牙槽嵴严重萎缩的无牙下颌患者的治疗程序，重点介绍了修复体制作要点，评价了种植覆盖义齿的修复效果。方法：在每个无牙下颌前牙区植入2～3枚Replace种植体、或MIC种植体。连接基台，制作做固位用的杆结构。覆盖义齿通过放置在组织面的塑料或合金夹子固位到杆结构上.用该方法修复严重萎缩的无牙下颌19例，其中，17位患者按期进行了复查，从种植效果和修复效果两个方面对复查患者的治疗结果进行了评价。结果：17位按期复诊者的43枚种植体及其支持的杆结构稳定。修复后咀嚼功能恢复良好，面容和语音功能有显著改观，患者对种植修复治疗结果都感到满意。结论：用种植组合体固住的下颌半口覆盖义齿修复严重萎缩的无牙下颌，能够有效地恢复咀嚼功能，改善面容，提高语音的清晰度，达到预期的效果。     

软衬材料固位的全下颌种植覆盖义齿三维有限元应力分析

目的 探讨弹性缓冲装置对种植覆盖义齿应力分布的影响，为优化种植覆盖义齿设计提供依据。方法 应用三维有限元法，对采用弹性软衬材料和非弹性材料固位的全下颌种植覆盖义齿进行应力分析，对比义齿本身和支持组织应力分布的差异。结果 ①无弹性材料缓冲的覆盖义齿对斜向载荷的抵抗性差，种植体颈部—皮质骨界面应力峰值为垂直载荷的2．4～9．2倍。垂直及斜向载荷，种植体及基托均有较高的应力集中。②弹性软衬材料固位的覆盖义齿，垂直及斜向载荷时，种植体—骨界面及义齿本身应力分布较均匀，避免了较大的应力集中。结论 弹性软衬材料应用于全下颌种植覆盖义齿时，表现了良好的应力缓冲作用，降低了种植体—骨界面应力峰值，减少机械性并发症的发生，有利于提高种植覆盖义齿的远期成功率。     

下颌无牙颌杆卡种植覆盖义齿修复的临床疗效观察

目的 评价下颌杆卡种植覆盖义齿的临床效果。方法 15例下颌牙列缺失患者，分别制作成粘膜支持型、种植体粘膜共同支持型和种植体支持型杆卡种植覆盖义齿。戴牙后定期检查义齿固位力、稳定性和种植体周牙龈状况，摄X线片了解种植体骨结合状况。结果 修复后随访2年，种植体周牙龈状况基本正常，X线片显示种植体与骨结合良好，种植体周骨平均丧失0．7mm，粘膜支持型组患者牙弓后段牙槽嵴吸收逐渐加重，义齿前后翘动度加大；种植体支持型和共同支持型组患者均未发现牙弓后段牙槽嵴有明显的吸收。结论 杆卡固位种植覆盖义齿具理想固位力和稳定性，粘膜支持型设汁会导致牙弓后段牙槽嵴明显吸收，须慎用。     

下颌种植覆盖义齿修复后满意度的调查分析

目的 比较牙列缺失患者行下颌半口义齿和下颌种植覆盖义齿修复的主观感受。方法 对16例戴用下颌半口义齿后又行下颌种植义齿修复的患者，采用自拟修复前初诊问卷和种植修复后问卷调查，由患者本人就诊时填写。结果 种植固定义齿与下颌半口义齿在舒适、功能、固位等方面存在明显差异。结论 牙列缺失患者行下颌杆卡式种植覆盖义齿，较下颌半口活动义齿修复能更好地满足患者需求，获得高质量的义齿。     

种植体磁性固位下颌覆盖总义齿的应用

目的：探讨种植体磁性固位下颌覆盖总义齿的临床应用。方法：在下颌全口缺牙且伴有牙槽骨重度吸收患的前牙区选择性植入2－4颗BLBC种植体，4－5个月后全口义齿修复，藏牙3周后，在种植体上旋转磁固位的上部结构并安装永磁体在相对应的义齿组织面内。分别测量患使用种植体一磁固位系统前后的固位力、咀嚼效率。结果：下颌总义齿的固位力、咀嚼效率在使用磁性固位体前、后均存在显性差异。结论：种植体支持的磁固位覆盖总义齿，对于改善下颌全口缺牙且伴有牙槽骨重度吸收患的咀嚼功能有一定作用。     

Non‐submerged osseointegrated dental implants with ball attachments supporting overdentures in patients with mandibular alveolar ridge atrophy. A short‐term follow up.

Non‐submerged, hollow screw ITI‐Bonefit dental implants with ball attachments supporting overdentures were used as alternative treatment to combined vestibulo‐lingual‐plasty with free split‐thickness skin graft and removable dentures in 40 consecutive patients with mandibular alveolar ridge atrophy. One hundred and fifty‐six non‐submerged fixtures were installed. Ball attachments were mounted on the fixtures and implant‐supported overdentures inserted 34 months after fixture installation. The observation period after implant activation and prosthesis insertion varied from 1 to 3 years with a median observation period of 2 years. The overall success rate of individual implants was 99%(155/156). The prosthesis function rate was 100%(40/40). The 1‐year success rate of individual implants was 99%(155/156) with a prosthesis function rate of 100% 40/40. No persistent surgical, periodontic or prosthodontic complications were observed. The results indicate that non‐submerged osseointegrated ITI‐Bonefit dental implants with ball attachments supporting overdentures can be a successful alternative to combined vestibulo‐lingualplasty with free split‐thickness skin graft and removable dentures, and as successful as the use of submerged dental implants.     

In vitro investigation of various attachments for overdentures on osseointegrated implants

summary Primary splinting of fixtures with bar attachments has proved to be clinically effective for overdentures on osseointegrated implants in the edentulous mandible. However, in vitro investigations indicate that a more favourable force transfer to the individual fixtures can be attained by secondary splinting of four implants with conical double crowns. This observation could be confirmed in the present study by measurement of implant deflection in a model of the mandible by means of interferometric optical holography. Telescope crowns with conical interface brought about functionally more even movement characteristics of the implants compared to rigid or jointed bar attachments. Moreover, the conical double crowns always ensured a stable position of the denture in contrast to jointed attachments. These results underscore the need to test conical double crowns clinically as anchors for overdentures on osseointegrated implants.     

A long-term study of implants supporting overdentures as a model for implant success

BACKGROUND: Implant-supported overdentures have been a common treatment for edentulous patients for the past 20 years, achieving good clinical results. The purpose of this study was to examine survival and success rates of implants supporting overdentures in the maxilla and mandible and to examine the influence of factors related to patients, implant procedure, implant data, and follow-up period on implant success. METHODS: During a 10-year period (1990 to 2000), 285 implants were placed in 62 patients to support 69 overdentures (seven patients had overdentures in both jaws). Patients ranged in age from 45 to 85 years (mean 64.5 years). The files of 61 patients, including 277 implants supporting 68 overdentures (14 maxillary and 54 mandibular), had measurable radiographic post-exposure follow-up (range 6.63 to 110.93 months, mean 37.93 months) for cervical bone loss (CBL) measurements. Bone loss was measured by radiographic examination in which the mean number of exposed threads in mesial and distal sides of the implant was considered. Implants were rehabilitated by overdentures with bar (N = 52) or ball (N = 16) attachments. RESULTS: Implant survival rate was 96.1% (11/285 did not survive) and total 10-year cumulative survival rate was 95.4% (maxilla, 83.5%, mandible, 99.5%). The success rate was 70.4% (maxilla, 41.9%; mandible, 80.8%) when using Albrektsson et al. success criteria. A logistic regression analysis showed that the maxilla (P <0.0001) and a short follow-up period (up to 5 years) (P = 0.017) were the most influencing factors enhancing CBL. CONCLUSIONS: 1) Survival of implants supporting overdentures was very high; 2) implants supporting overdentures in the maxilla had greater CBL than in the mandible; and 3) new criteria of implant success should be considered.     

Marginal tissue response adjacent to Astra Dental Implants® supporting overdentures in the mandible. A 2‐year follow‐up study.

The aim of this study was to evaluate the marginal tissue response adjacent to implant supported overdentures. Twenty edentulous patients had 2 Astra Dental Implants® placed in the canine region of the lower jaw. New overdentures were retained by individual ball attachments in 11 patients and by a bar attachment in 9 patients. Periodontal registrations were recorded 0 months, 6 months, 12 months and 24 months after the overdentures were inserted. One of the 40 fixtures was lost at the stage of abutment connection. No fixtures were lost during the 2‐ to 4‐year observation period and no fixtures showed any periodontal signs of failure. At the 2‐year examination, no pocket depths adjacent to the implants exceeded 4 mm and no bone loss exceeded 3 mm. The mean annual bone loss was less than 0.2 mm during the first 2 years. The preliminary results from this limited study were promising and showed that two osseointegrated Astra Dental Implants® could successfully retain an overdenture in the lower jaw. However, long‐term observation is needed for a definate evaluation of this treatment concept.     

Mandibular overdentures stabilized by Astra Tech implants with either ball attachments or magnets: 5-year results

PURPOSE: The purpose of this work was to report on the use of implant-stabilized overdentures in the mandible using the Astra Tech implant system with either ball attachments or magnets as the retentive mechanism. MATERIALS AND METHODS: Mandibular overdentures that used ball attachments on 2 implants were provided for 13 edentulous patients; 12 edentulous patients were provided with mandibular overdentures with magnet retention, using 2 implants in 10 patients and 3 implants in 2 patients. Once they were comfortable, the participants were placed on annual recall. Any other visits were initiated by the patients. Detailed records were kept for all visits. At the annual recall the following parameters were monitored: plaque levels, mucosal health, marginal bone levels, and the patients' assessment of the treatment. The patients were followed for 5 years. RESULTS: There was no statistical difference between the 2 groups for mucosal health and postinsertion maintenance. The magnet group had more abutment surfaces covered with plaque. Statistical analysis of the patients' subjective assessment of their treatment showed that the magnet group was less comfortable and chewing was less effective. CONCLUSION: The results indicate that both ball attachments and magnets used on isolated Astra Tech implants in the mandible are viable treatment options. Both attachment mechanisms provided patient satisfaction, although the ball attachments were better in this respect than the magnets.     

Implant-supported mandibular overdentures retained with ball or telescopic crown attachments: a 3-year prospective study

PURPOSE: The aim of the present study was to evaluate implant survival, peri-implant conditions, and prosthodontic maintenance requirements for implant-supported mandibular overdentures in atrophic mandibles retained with ball or resilient telescopic crown attachments during a 3-year period. MATERIALS AND METHODS: Twenty-five patients with edentulous mandibles each received 2 Camlog root-form dental implants in the mandibular interforaminal (canine) region. The denture attachment system was chosen randomly; 13 patients received ball attachments and 12 patients received resilient telescopic crowns. Implant survival, implant mobility (Periotest values), and peri-implant conditions such as bone resorption, pocket depth, Plaque Index, Gingiva Index, Bleeding Index, and Calculus Index values were assessed for each implant. In addition, detailed prosthodontic maintenance was evaluated during the follow-up period and the 2 retention modalities were compared. RESULTS: There were no differences in implant survival, implant mobility (Periotest values), and peri-implant conditions between the 2 retention modalities. During the 3-year period significantly more complications/interventions for maintenance purposes were registered in the ball group (62 interventions) than in the telescopic crown group (26 interventions; P < .01). CONCLUSION: The results indicate that both ball attachments and resilient telescopic crowns used on isolated implants in the edentulous mandible are viable treatment options. Implant success and peri-implant conditions did not differ between ball attachments and telescopic crowns used as retention modalities for implant overdentures, but the frequency of technical complications was significantly higher with ball attachments than with resilient telescopic crowns.     

Implant-supported mandibular overdentures retained with ball or bar attachments: a randomized prospective 5-year study

PURPOSE: The aim of the present study was to evaluate the periimplant conditions and the maintenance requirements for implant-supported overdentures in the mandible retained with ball or bar attachments during a 5-year period. MATERIALS AND METHODS: Twenty-six completely edentulous patients had two Astra Tech dental implants placed in the anterior part of the mandible. The denture attachment system for the patients was chosen randomly by drawing lots. Eleven patients drew the bar attachment system and fifteen patients drew the ball attachment system. Plaque Index, Gingival Index, and probing pocket depth were assessed around each implant. Periotest values were recorded, and periodically identical intraoral radiographs were obtained with a specially designed film-holding device. RESULTS: No implants were lost from baseline to the 5-year registration. The periimplant conditions were very healthy after 5 years. No significant differences of the periimplant variables were recorded between the bar and the ball groups. During the first year of function, significantly more complications/repairs were registered in the bar group than in the ball group. In the following years, no significant differences were registered. The mean frequency of complications/repairs per patient per year was 1.0 in the bar group and 0.6 in the ball group during the 5-year observation period. CONCLUSION: Two implants with ball or bar attachment supported an overdenture in the mandible for 5 years with a 100% survival rate. No differences in marginal bone loss or health of the periimplant mucosa were observed between bar and ball attachment, but the frequency of technical complications/repairs per patient was higher around bar than ball attachments.     

Immediate loading of dental implants placed in severely resorbed edentulous mandibles reconstructed with autogenous calvarial grafts

OBJECTIVE: The aim of this prospective study was to present the clinical outcome of immediately loaded dental implants placed in edentulous, severely atrophied mandibles, after reconstruction with autogenous multilayered calvarial grafts. MATERIALS AND METHODS: Six patients, two males and four females, aged 40-67 years (mean: 56 years) presenting with severely atrophied edentulous mandibles (Cawood and Howell class VI), were reconstructed with multilayered calvarial bone grafts placed in the intraforaminal area of the mandible. Five to 8 months afterwards, 23 dental implants were placed in the reconstructed areas (three to four implants per patient) and immediately loaded with implant-supported overdentures. Patients were followed with clinical and radiographic controls annually. RESULTS: Recovery after the reconstruction was uneventful in all patients. All 23 implants were osseointegrated 1-3 years after the start of immediate loading. The survival and success rates of implants were 100% and 95.7%, respectively. CONCLUSION: Results from this study showed that immediate loading of dental implants placed in severely atrophied edentulous mandibles reconstructed with calvarial bone grafts is a predictable procedure, which permits a successful dental rehabilitation with a shortening of treatment times.     

ITI implants with overdentures: a prevention of bone loss in edentulous mandibles?

Changes in the bone mineral content (BMC) of edentulous mandibles with osseointegrated ITI implants supporting overdentures were measured in vivo by dual-photon absorptiometry. The BMC measurements were performed 3 weeks postoperatively and at the 2-year follow-up visit. Measurements were made in the ITI site (anteriorly), the premolar region just behind the fixtures, and the standard site of the mandible for obtaining reference values of the age-related MBC loss. The increased function of the mandible after this treatment seems to cause a load-related bone formation that minimizes, or in some cases may counteract, the physiologic age-related BMC loss leading to osteoporosis.     

Two-implant mandibular overdentures: simple to fabricate and easy to wear

Success rates for titanium dental implants in the anterior mandible are very high. Because of these success rates, as well as lower costs, it is common to treat edentulous patients with just 2 implants and ball anchors for retention of the overdenture, instead of 4 implants and a bar. In this paper the fabrication of 2-implant overdentures is described. In a controlled clinical trial (to be reported elsewhere), 30 subjects received a 2-implant overdenture for the mandible and a conventional prosthesis for the maxilla. The 30 control patients received conventional complete dentures for both jaws. The stability of the overdentures was excellent, and the lingual dimensions of the denture could be reduced to the level of the mylohyoid line to provide more space for the tongue. In patients with tense labial musculature or a limited amount of attached gingiva, it was important to elevate the shoulder of the implant and ball abutment above the gingival level to avoid peri-implant problems. Significantly fewer visits for adjustment related to post-placement pressure spots were required for mandibular overdentures than for conventional mandibular prostheses.