种植区CT骨密度与扭矩相关性研究

目的通过研究种植区CT骨密度值与扭矩值之间的关系来预测种植体的初期稳定性。由此通过CT扫描来决定该区骨质状况是否适合种植,制定出更加可靠的治疗计划。方法该样本选取了本院12例种植患者的58颗种植体。利用Simplant种植设计软件根据CT影像数据来选择种植位点并制作手术导板,通过软件来测量模拟种植体周围的CT平均骨密度值,通过手术导向模板引导钻孔,按既定的位置植入种植体。测量种植体旋入时所用的扭矩,统计骨密度值与扭矩值并分析两者之间的相关性。结果在临床病例的评估中,骨密度与扭矩之间有着很大的相关性,相关系数为0.671。结论通过术前CT分析及种植模拟可以定量种植位点的骨质,并预测种植体初期稳定性。由此可以帮助手术医师选择最合适的种植方位,种植类型以及外科种植技术,从而制定出更加可靠的治疗计划。     

上颌后牙区骨量不足条件下的牙种植术研究进展

<正>种植体植入区具有足够量的健康骨组织是牙种植成功的关键因素之一,然而由于天然牙拔除后,牙槽骨即发生生理性吸收,剩余牙槽嵴的宽度在1年内将减少约25%,且此过程持续进行,最终可导致50%的牙槽骨丧失。而上颌后牙区由于上颌窦的存     

即刻牙种植近期临床效果研究

目的探讨即刻牙种植的近期临床效果及手术技巧。方法 25颗无法保存的牙齿微创拔除后,即刻植入种植体,采用骨引导再生技术16例,采用埋入式愈合技术19例,非埋入式愈合技术6例,在3～8个月后全部完成修复,修复后平均追踪12个月,进行定期的临床和X线片检查。结果 25颗种植体均达到骨整合标准,获得成功,使用良好。复查X线片种植体颈部边缘骨吸收均小于1.5mm。结论术前认真分析,灵活运用手术技巧,即刻种植可以取得良好的近期临床效果。     

后牙区线性体层X线影像在牙种植术前设计中的应用

目的：分析后牙区线性体层X线影像在口腔种植术前设计的应用价值。方法：54例上下颌后牙区缺牙,拟行种植修复的患者,接受术前X线检查,采用sirona公司数字化牙科X线机ORTHOPHOSXGplus对拟手术区行线性体层及曲面体层X线摄影,对得到两种X线影像,利用SIDEXIS5.0软件的测量功能和定位钢珠在拟种植方向上的影像放大率校正后,分别测得种植区骨量,即牙槽嵴顶到下颌管上缘或牙槽嵴顶到上颌窦底的高度,采用配对t检验的统计学分析方法,分析测量值的差异有无统计学意义。结果：在两种投照方法得到的X线影像上,测得的骨量值间差异无显著性（P〉0.05）;线性体层x线影像可以更直观地了解拟种植区重要解剖结构,便于指导种植体植入的方向,尽可能地利用牙槽骨骨量,同时避免损伤重要解剖结构。结论：在后牙区,应用线性体层X线影像结合曲面体层X线影像的方法,做牙种植术前设计,可以近一步降低种植手术损伤重要结构的风险。     

15例上颌前牙种植的美学临床研究

目的：评价ITI种植系统用于上颌前牙列缺损修复的临床应用和短期疗效并总结牙种植治疗中的经验教训。方法：50例患者的缺牙区植入ITI种植体78颗并完成义齿修复,临床观察12～36个月,其中15例为上颌前牙区种植美学修复。6例上颌植入区骨量不足者,用Bio-Oss人工骨粉植入缺损区及Bio-Gide可吸收生物膜覆盖。结果：50例患者总共78颗种植体稳固无松动,种植部位无疼痛或不适,短期种植成功率100%。2颗上颌前牙种植修复后牙龈乳头缺失。患者满意度为92.3%。结论：ITI种植系统在牙列缺损修复中有的成功率很高,但患者对前牙缺损修复美学效果要求也越来越高,软组织的处理对最后的美学效果十分重要。     

牙周炎患者即刻修复的临床观察

目的：对牙周炎患者行即刻修复进行临床观察研究。方法：选择于2008年5月至2009年5月期间在中山大学光华口腔医学院附属口腔医院种植科就诊的具有牙周炎病史的牙列缺损或牙列缺失患者,共31例（男16例,女15例）。所有患者均已行完善的牙周治疗。共植入种植体107枚,均于手术当天完成树脂临时修复。术后3个月行永久修复。结果：31例107枚种植体中,下颌18例66枚种植体,上颌13例41枚种植体,修复后成功率为100%.结论：牙周炎病史患者行完善的牙周治疗后,行种植即刻修复也可获得满意的短期临床效果。     

种植导航模板的计算机辅助设计和制造

目的：采用计算机辅助设计和制造技术制作种植导航模板,以确保种植体植入的安全性,获得理想的植入位置和方向。方法：应用牙科CT扫描患者上下颌牙弓,并转换成三维模型;取模并翻制牙颌石膏模型,测量牙颌石膏模型表面三维数据,获得点云数据文件,并转换成三维模型,并与CT获得的三维模型配准。按照种植体植入标准和要求计算机辅助设计种植导航模板,利用数控激光快速成型技术制作模板。结果：完成的计算机辅助设计和制造的种植导航模板实物质量稳定,精度较高。结论：种植导航模板能在术前确定种植位置以及方向,术中具有导航作用,具有一定的应用前景。     

Influence of Cusp Inclination on Stress Distribution in Implant‐Supported Prostheses. A Three‐Dimensional Finite Element Analysis

Purpose: The aim of this study was to assess the influence of cusp inclination on stress distribution in implant‐supported prostheses by 3D finite element method. Materials and Methods: Three‐dimensional models were created to simulate a mandibular bone section with an implant (3.75 mm diameter × 10 mm length) and crown by means of a 3D scanner and 3D CAD software. A screw‐retained single crown was simulated using three cusp inclinations (10°, 20°, 30°). The 3D models (model 10d, model 20d, and model 30d) were transferred to the finite element program NeiNastran 9.0 to generate a mesh and perform the stress analysis. An oblique load of 200 N was applied on the internal vestibular face of the metal ceramic crown. Results: The results were visualized by means of von Mises stress maps. Maximum stress concentration was located at the point of application. The implant showed higher stress values in model 30d (160.68 MPa). Cortical bone showed higher stress values in model 10d (28.23 MPa). Conclusion: Stresses on the implant and implant/abutment interface increased with increasing cusp inclination, and stresses on the cortical bone decreased with increasing cusp inclination.     

Implant‐Supported Obturator Overdenture for Extensive Maxillary Resection Patient: A Clinical Report

This clinical report presents an implant‐retained obturator overdenture solution for a Prosthodontic Diagnostic Index Class IV maxillectomy patient with a large oronasal communication and severe facial asymmetry, loss of upper lip and midfacial support, severe impairment of mastication, deglutition, phonetics, and speech intelligibility. Due to insufficient bone support to provide satisfactory zygomaticus implant anchorage, conventional implants were placed in the body of the left zygomatic arch and in the right maxillary tuberosity. Using a modified impression technique, a cobalt‐chromium alloy framework with three overdenture attachments was constructed to retain a complete maxillary obturator. Patient‐reported functional and quality of life measure outcomes were dramatically improved after treatment and at the two‐year follow‐up.     

Bacterial Persistence in Dentoalveolar Bone Following Extraction: A Microbiological Study and Implications for Dental Implant Treatment

Background: The microbiological status of apparently healed alveolar bone implant sites is unknown. Implant success may be compromised by site‐specific persistence of bacterial biofilm co‐aggregations contaminating healed alveolar bone. Purpose: The purpose of the present study was to investigate whether extraradicular infection can persist in apparently healed alveolar bone and to develop a surgical debridement strategy that favors implant osseointegration. Materials and Methods: The study was conducted on 32 private practice patients. Seventy‐seven microbiological samples were taken from 16 pre‐implant extraction sockets, 56 healed post‐extraction osteotomies at fixture placement, and five failed fixtures. Two of the healed osteotomy samples were healed retreatment sites. Tissue fluid and bone samples were analyzed by either anaerobic/aerobic culturing or DNA molecular techniques. All patients were treated ad modum Brånemark, with a two‐stage sterile surgical procedure. A search of the medical and dental literature revealed no evidence‐based or best practice recommendations for the use of debridement in implant therapy. Thus, we developed a new technique for the debridement of alveolar bone found to be contaminated by persistent biofilm or planktonic bacteria. Results: The results of the microbiological analysis of 77 bone and effusion samples from 47 implant sites of the 32 patients showed that overall, 32% (n = 25) had bacteria present in the sample. In 16 pre‐implant extraction sockets, 69% of samples were positive for the presence of bacteria (n = 11). Of 56 osteotomies with a minimum 3‐month healing at fixture placement, 21% revealed a positive culture (n = 12). Two‐stage failed fixtures had 100% positive cultures (n = 5) and it was evident from radiographs that all of these failed fixtures had the apical ends close to the former tooth root end. Based on these findings, we have developed a microbiologically based surgical debridement strategy to successfully re‐treat early infective failures and to place successful two‐stage fixtures. Conclusion: Bacteria can persist as a contaminant in apparently healed alveolar bone following extraction of teeth with apical or radicular pathosis. A new technique for surgical debridement to reduce and limit this bacterial contamination has been described.