Osseointegrated dental implants in conjunction with bone grafts

This paper relates to the experience with 12 patients who received osseointegrated dental implants of the Branemark design associated with bone grafts. 4 patients had iliac crest grafts, 2, of which were inserted together with the implants. Two had metatarsal reconstruction of the anterior mandible with the implants installed at a later date. 2 patients had particulate marrow grafts with immediate installation of the implants. Of the remainder, 1 had a late implantation of a myo-osseous flap utilizing the clavicle and the other delayed implantation of a split rib graft. The mean age of the patients in this series is 49.5 years. The mean loading time for completed cases is 18 months. 7 patients have had their dentition successfully restored, 3 lost the initial implants, 2 of which have been re-operated. One patient died prior to loading and one awaits the final surgical procedure. The results of the particulate marrow and split rib grafts were disappointing. The remainder suggest that osseointegrated dental implants may be utilized with appropriate bone grafting techniques to restore the dentition in patients with severe bone loss or following the surgical ablation of malignant disease.     

Use of HTR synthetic bone as an augmentation material in conjunction with immediate implant placement: a case report

Immediate placement of dental implants (DI) in fresh extraction sockets is associated with remaining voids around the DI and often a partial dehiscence or thin facial alveolar plate. Bioplant HTR synthetic bone (HTR) was used as a ridge preservation/augmentation material in conjunction with this method of DI placement. A 61-year-old white woman requiring extraction of tooth 12 opted for immediate DI placement. HTR was used to fill the remaining socket void and enhance the facial ridge width, and primary closure was attempted with sutures. DI uncovering was performed at about 6 months. Measurements were taken to the nearest 0.5 mm of the internal socket width and total site width at DI placement and uncovering. The internal socket width was essentially maintained (6.8 vs 6.6 mm), and the total ridge width showed a change from 8.7 to 9.1 mm. The results of this case suggest that HTR is a useful adjunct in the placement of immediate DIs for the preservation of ridge width.     

骨移植与骨引导再生技术联合应用修复种植体周围骨缺损的实验研究

目的:评价不同的骨移植材料结合钛膜和胶原膜修复种植体周围骨缺损效果,为临床决策提供实验依据.材料与方法:8条健康成年杂种犬拔除双侧下颌前磨牙3个月后,每侧缺牙区植入4枚钛钉,并于钛钉颊侧制造骨缺损,分别植入自体骨、Bio一oss、1:2的自体骨和Bio-oss混合物、2:1的自体骨和Bio-oss混合物.两侧分别覆盖钛膜和胶原膜.5个月后取材,通过影像学、组织学和免疫组化学技术观察骨缺损区生成新骨的质量和成骨活性.结果:种植钉无松动脱落.2例钛膜暴露但无脱落,无胶原膜暴露.钛膜下的钛钉顶部被新生骨覆盖,在胶原膜覆盖的钛钉颊侧骨面凹陷,钛膜侧新骨高度大于胶原膜组.X线片可见钛钉与骨结合紧密,钛膜侧植骨区饱满,密度较高.硬组织磨片显示种植钉与植骨材料形成了良好的骨整合,胶原膜组的骨-种植体接触率(BIC)和种植体周围骨面积(BA)均略高于钛膜组,但两者无统计学差异.2:1自体骨和Bio-oss的混合物的BIC和BA均高于1:2比例组,有统计学差异.2:1比例组与1:2比例组植骨材料相比,骨缺损处新生骨成熟度高.饱和苦味酸-天狼猩红-偏振光法和免疫组织化学SABC法观察I型胶原和骨钙素,各组未见存在显著差异.结论:自体骨、Bio-oss及自体骨和Bio-oss不同比例的混合物,在修复种植体周围3mm骨缺损时,均可获得满意效果,但自体骨比例大者骨整合程度更好.钛膜下新骨生成量大于胶原膜,但质地和活性无明显区别.讨论:修复种植体周围小的骨缺损(＜3mm)时,选用哪种骨移植材料都可以.钛膜虽然容易暴露,但它的帐篷作用好,其下成骨量大,价格便宜,适于国内推广使用.     

非血管化骨移植种植体以及即刻种植体与软组织结合的实验观察

目的:观察非血管化骨移植种植以及即刻种植体钛金属表面与软组织的结合状况,分析影响二者结合的因素。方法:拔除狗的一侧下颌前磨牙,4周后截除无牙下颌骨段,自体非血管化髂骨移植同时植入纯钛种植体修复下颌骨缺损。对照组动物拔除一侧下颌前磨牙时同期在牙槽窝内植入同样的种植体,缝合牙龈。在术后4、8、16周处死动物,以40g/L中性多聚甲醛灌注固定后,取种植体颈部周围软组织。肉眼观察2组动物种植体与周围软组织结合的紧密程度;HE染色观察结合上皮的组织结构;透射电镜观察结合上皮与种植体结合面细胞超微结构。结果:2组动物在术后4周时,种植体顶端已出龈暴露在口腔内,颈部周围的软组织已达初步封闭;两者的结合还较疏松,软组织较薄,细胞膜的表面突起较少。术后8周时,种植体的颈部软组织已完全封闭,软组织与钛表面结合紧密,即刻种植组动物可见明显的结合上皮;超微结构可见结合上皮有较多的细胞膜突起。术后16周,2组的结果与8周时相似。整个实验过程未发现桥粒结构的形成。结论:在没有明显创伤和感染的情况下,两者均可形成良好的结合;即刻种植体与周围软组织结合较非血管化骨移植种植体更致密。2种种植方法结合上皮与钛表面都不能形成桥粒结构。     

Success of dental implants placed in intraoral block bone grafts

BACKGROUND: The purpose of this study was to evaluate the survival and success of dental implants placed in alveolar bone following augmentation using intraoral block bone grafts. METHODS: A consecutive retrospective study was conducted on patients who had onlay bone grafts for vertical or horizontal augmentations followed by dental implantation from 1999 to 2001. Files of 50 healthy patients who received 129 implants in augmented sites were reviewed. Implant survival, radiologic implant success (marginal bone loss), and complications were recorded. RESULTS: Follow-up from time of implantation ranged from 6 to 67 months (mean: 24.3 +/- 11.2 months). Ranges of implant widths and lengths were 3.25 to 4.7 mm and 10 to 16 mm, respectively. The overall survival rate was 96.9% (four implants were removed). Marginal bone loss around implants ranged from 0 to 3.3 mm (average: 0.22 +/- 0.45 mm). Only 5% of the implants presented marginal bone loss > or =1.5 mm over the follow-up time. CONCLUSIONS: Intraoral bone block graft surgery is a predictable operation for the use of dental implants. Implant placement in augmented areas presents high survival and radiologic success rates with minimal bone loss.     

嵌贴式植骨术在牙槽嵴严重吸收患者牙种植术中的应用

目的:总结嵌贴式植骨方法进行缺牙后重度吸收牙槽嵴骨增量的植骨技术及其效果。方法:15例重度吸收牙槽嵴患者接受了嵌贴式植骨术,分别于植骨12～24周后植入种植体,共植入26枚种植体。术后16～24周行种植体基台连接术及烤瓷冠或烤瓷桥修复。结果:术后12周复诊二期植入种植体者,术中见植骨块吸收很少,所有患者均成功完成了种植修复。15例植骨患者中,3例出现术后感染,但仍获一定程度的骨增量效果,12例无并发症。所有病例修复后追踪24～48周,无种植体脱落。结论:嵌贴式植骨技术应用于严重吸收牙槽嵴骨增量操作简单,效果可靠。     

Placement of implants into ridges grafted with bioplant HTR synthetic bone: histological long-term case history reports

Following alveolar ridge grafting procedures for ridge preservation, for example, the immediate filling of extraction sockets, and ridge augmentation, for example, the building up of the atrophic jawbone, punch biopsies were obtained at various times postextraction prior to the placement of endosseous root-form implants. These histological sections provided an opportunity to study the bony regenerative response to an osteoconductive synthetic graft material and longer term interactions over a period from 8 months to 12 years. The formation and remodeling of healthy dense lamina of bone in areas where bone voids previously existed either from healed or immediate extraction sockets or where there was jawbone atrophy resulting from multiple tooth loss was observed. The grafting procedures enabled dentists to place implants into sites that would have been impossible if not for these preimplant grafting procedures. The jawbone areas studied involved grafted single sites and quadrants as well as full arch augmentation with a calcified microporous copolymer (Bioplant HTR Synthetic Bone, Bioplant Inc, South Norwalk, Conn) graft material. Retrospective case reports of 24 patients were followed radiographically and clinically to 12 years post-alveolar-ridge grafting and subsequently to 5 years after implants were placed into these augmented ridges. Implant and grafting histories from 4.7 months to 17 years are reported for three of these patients. General applications of synthetic bone grafting before implant placement are recommended.     

The immediate loading of dental implants

The aim of this article is to identify current opportunities for the immediate loading of endosseous dental implants. A biologic basis for the clinical parameters associated with success and failure of immediately loaded implants is presented, and select clinical situations where immediate loading is presently advocated will be illustrated. The wide-ranging applications of the immediate-loading concept for endosseous dental implants will be introduced; however, further experimental validation is necessary before incorporating all of these various expedited therapeutic approaches into practice.     

Inter-implant bone height changes in anterior maxillary immediate and non-immediate adjacent dental implants

BACKGROUND: The purpose of this study was to evaluate inter-implant bone crest height changes between immediate and non-immediate dental implants placed in the anterior maxillary region. METHODS: A retrospective study was conducted on consecutively treated patients requiring at least two adjacent implants in the anterior maxillary region that were placed in the same operation during 1994 to 2004. Files of 45 healthy patients reporting 200 implants were reviewed. Age, gender, smoking status, and implant characteristics (coating and dimensions) were recorded. Inter-implant bone measurements were taken on two panoramic radiographs from each patient: one after implant placement and the other at the last follow-up. The distance between adjacent implants was measured at the implant-abutment interface (implant platform). RESULTS: Overall, 130 inter-implant gaps were found. Follow-up ranged from 8 to 146 months. Two-tailed Pearson correlation tests revealed a negative correlation between inter-implant distance and bone loss (P = 0.036). Mean peak-crest bone loss for immediate implants was higher than for delayed implants (P = 0.026). There was more bone loss when hydroxyapatite (HA)-coated implants were used, although no statistical significance was observed. No statistically significant difference was found between the different locations in the anterior maxilla. No correlation was found between patient's age, smoking habits, and bone loss or between follow-up time and bone loss. CONCLUSIONS: A negative correlation was found between inter-implant distance and bone loss at the inter-implant bone crest in the anterior maxillary region. Bone loss was small in this study cohort.     

A comparative evaluation of immediate dental implant with autogenous versus synthetic guided bone regeneration

Immediate implant is a placement of the implant immediately into fresh extraction socket site after tooth extraction and is considered to be a predictable and acceptable procedure. The present work is designed to evaluate the periodontal condition after immediate implant placement and the success rate of implant with autogenous versus synthetic guided bone regeneration. Twenty adult male patients with an endodontic failure, tooth fracture decayed tooth (hopeless tooth) were included in this study. Patients were divided into 2 groups: One group (I) received immediate implants augmented with autogenous bone graft, and the other (group II) received immediate implants augmented with a synthetic bone graft. The results revealed that there was a significant difference between the groups for pocket depth and clinical attachment level. The difference between the groups was statistically highly significant only at 12 months (P < .01). In addition, there was statistically significant difference between the groups at 9 and 12 months (P < .001). Moreover, there was significant decrease of marginal bone loss in group I compared with group II (P < .01). In addition, there was statistically significant difference between the both groups at 9 and 12 months for bone density (P < .001). Moreover, there was significant decrease of marginal bone loss in group I compared with group II (P < .01). In conclusion, the immediate dental implant placement with autogenous bone graft showed a significant superiority to synthetic bone graft. In addition, the immediate placement-delayed loaded dental implant remains the procedure of choice for predictable achieving of osseointegration.     

Influence of platelet-rich plasma added to xenogeneic bone grafts on bone mineral density associated with dental implants

PURPOSE: The purpose of this study was to assess the bone mineral density changes after bone regeneration therapy using xenogeneic demineralized freeze-dried bone graft (DFDBG) plus platelet-rich plasma (PRP) and DFDBG alone in 3-wall peri-implant defects in dogs. MATERIALS AND METHODS: The mandibular premolars and molars of 9 adult hound dogs were removed surgically, and 90 sites were prepared for implant placement. Before implant placement, a total of 162 mesial and distal 3-wall peri-implant defects were surgically created. Defects were randomly assigned to three groups: DFDBG + PRP, DFDBG alone, and no treatment. Animals were sacrificed at 1, 2, and 3 months, and specimens were subjected to bone mineral density (BMD) and bone mineral content (BMC) analysis with a peripheral dual x-ray absorptiometry densitometer. RESULTS: The effect of treatment on BMD and BMC differed significantly by month of sacrifice (P = .030 and P = .035 for the month-by-treatment interactions, respectively). BMD differed significantly between peri-implant defects treated with DFDBG alone and untreated defects at 3 months (mean BMD of 0.6667 for DFDBG alone versus 0.5606 for untreated defects; P < .001). BMC also differed significantly between peri-implant defects treated with DFDBG alone and untreated defects at 3 months (mean BMC of 0.0276 for DFDBG alone versus 0.0236 for untreated defects; P = .001). No other pairwise comparison of the treatments within each month of sacrifice or at the overall treatment effect across all three months demonstrated significant differences. DISCUSSION: PRP has been proposed as an autogenous source of growth factors, which may increase the speed and completeness of healing. This study did not demonstrate a significant improvement in BMD or BMC when PRP was combined with DFDBG. Defects where grafting material was used, either with or without PRP, did demonstrate slightly greater BMD and BMC than those left untreated. CONCLUSION: This study found that the addition of PRP to xenogeneic bone grafts did not significantly alter BMD or graft maturity levels in this animal model.     

骨移植共同期或延期种植修复颌骨功能临床初探

目的:对2000年2月至2005年12月治疗的颌骨功能重建患者做回顾分析。方法:对8例因良性肿瘤术后,创伤造成颌骨缺损患者,进行骨移植,同期或延期种植术;选择性应用骨粉和骨生长引导膜;角化牙根移植,义齿修复。结果:8例患者共植入38枚种植体,除1枚未实现骨愈合外,37枚修复重建全部成功,取得颌面部外形与功能均理想效果。结论:颌骨损伤后,采用非血管化和血管化骨游离移植,进行即刻或延期牙种植修复技术,能使患者取得颌骨功能性重建。     

骨移植复合种植义齿进行颌骨缺损功能重建的临床研究

目的评估对颌骨缺损患者行自体骨移植复合种植义齿修复重建的临床疗效。方法自2007—2012年,对11例因肿瘤、外伤造成颌骨缺损的患者,进行自体骨移植及延期植入种植体,并进行种植体支持的义齿修复,对修复后患者口颌系统的功能、外观进行评价和随访。结果本研究11例患者的自体移植骨均成活;共植入41枚种植体,除2例共4枚种植体发生种植体周围龈炎外,其余种植义齿功能及美观恢复均较理想。结论由外伤或肿瘤引起的颌骨缺损采取血管化或者非血管化自体骨移植,复合种植义齿的应用,能为患者恢复较好的外形和功能;种植体周围进行角化牙龈的移植有利于种植义齿耐受摩擦及咀嚼压力,并有利于维护种植体周围黏膜组织的健康。     

Evaluation of hard tissue replacement composite graft material as a ridge preservation/augmentation material in conjunction with immediate hydroxyapatite-coated dental implants

BACKGROUND: Immediate placement of dental implants (DI) in fresh extraction sockets is associated with remaining voids around the DI and often a partial dehiscence or thin facial alveolar plate. Bone replacement grafts are often used to correct these problems. This study evaluated the use of a layered composite of PMMA (poly-methyl-methacrylate), PHEMA (poly-hydroxyl-ethyl-methacrylate), and calcium hydroxide grafts (HTR) as a ridge preservation/ augmentation material used in conjunction with an immediate DI placement technique. METHODS: Twenty-three patients requiring 1 or 2 extractions that were treatment planned for immediate DI placement received 4.0 or 3.25 mm diameter hydroxyapatite-coated cylindrical implants in the extraction sockets. HTR was used to fill the remaining socket void and enhance the facial ridge width. A collagen hemostatic was placed to cover the DI sites, flaps released, and primary closure attempted with sutures. DI uncovering was performed at about 6 months. Measurements were taken to the nearest 0.5 mm of the internal socket width and total ridge width at DI placement and uncovering. RESULTS: Thirty DIs were placed in the 23 patients. Mean initial internal socket width was 6.9 mm. The total ridge width showed a mean change from 9.1 mm to 8.4 mm; 60% of the areas showed a net increase or no change, while 40% showed a decrease in overall ridge width. DI success rate was 97% out to 6 months of loading. CONCLUSION: The results of this study suggest that HTR is a useful adjunct in the placement of immediate DIs for filling of socket voids and preservation of ridge width.     

Resonance frequency analysis in immediate loading of dental implants

Immediate loading of dental implants aims to shorten treatment time. Stability at implant insertion is critical to success. The aim of this prospective study is to compare primary implant stability, measured by insertion torque (IT) with resonance frequency analysis (RFA) expressed as ISQ. Patients requiring implant therapy were treated by teeth extractions, placement of 1-9 MIS implants, bone augmentation as needed and fixed provisional restorations. We measured IT and ISQ for non-submerged loaded (NSL), non-submerged non loaded (NSNL) and submerged (S) implants. 14 patients, aged 34-79 years, were recruited. 53 implants were inserted (38 maxillary & 15 mandibular). 30 implants, 18 in fresh extraction sites, were immediately loaded. ISQ was 63.3 +/- 2.8 (S.E.), 67.2 +/- 3.5 (S.E.) and 58.8 +/- 2.7 for the NSL, NSNL and S groups, respectively (p = 0.0459). IT was 40.4 +/- 1.8 Ncm, 46 +/- 4.0 and 35.3 +/- 2.1 (p = 0.0646). ISQ and IT were not statistically different between extraction vs. non-extraction and augmented vs. non-augmented sites. We found a significant difference in IT between maxillary & mandibular sites, and a significant correlation between ISQ & IT and between ISQ & implant diameter. These data suggest that ISQ is correlated to IT and is influenced mainly by implant diameter and not by implant length, location or bone level. Finally, a case including immediate implants, bone augmentation and immediate provisional restoration is presented.