Tomographic evaluation of iliac crest bone grafting and the use of immediate temporary implants to the atrophic maxilla

Sixteen consecutive patients with atrophic maxillae, who had been referred for bone augmentation using iliac bone grafting before the placement of dental implants, received a full clinical examination and underwent a CT scan before and after surgery. Linear vertical and horizontal measurements were made before and 6 months after surgery. Differences in mean bone gain or loss for each area were compared between a group that received an immediate total provisional prosthesis on temporary immediate implants (test group, 12 patients) and a control group (four patients). Both groups showed significant horizontal bone gain in all regions and vertical bone augmentation in the posterior regions. The test group showed no significant difference for bone gain compared to the control group, but half the test group had problems during treatment. Bone augmentation of the atrophic maxilla with iliac crest bone grafting resulted in sufficient vertical and horizontal bone augmentation to install six or eight implants in all patients and successfully rehabilitate them. The results suggest that the use of total provisional prostheses on temporary immediate implants meets the aesthetic demands required, but should be used with care and in special cases.     

Stability of bone grafting and placement of implants in the severely atrophic maxilla

A severely atrophic maxilla can be restored by bone grafts to allow the insertion of implants. We present 30 consecutive patients treated with autogenous inlay and onlay bone grafts from the iliac crest to the floor of the maxillary sinus and the alveolar crest. A total of 200 implants were inserted 4-6 months after bone grafting. A mean vertical increase in bone thickness of 14mm was achieved. After a mean bone loss of 1.3mm during the first year after bone grafting only minimal resorption was observed during the second and third year. Seven implants failed to integrate and a further four implants were lost during follow-up.     

Endosseous implants and bone augmentation in the partially dentate maxilla: an analysis of 17 patients with a follow-up of 29 to 101 months

PURPOSE: The aim of this study was to analyze the survival rate of endosseous implants placed in the partially dentate maxilla treated with sinus inlay block bone grafts. MATERIALS AND METHODS: Seventeen patients were subjected to bone augmentation procedures prior to or in conjunction with implant placement. Bone volumes were regarded as insufficient for implant treatment unless a bone grafting procedure was performed. The patients were treated with sinus inlay block bone grafts and endosseous implants in a 1- or 2-stage procedure. A total of 69 implants were placed in the patients who were followed for 29 to 101 months (mean, 53.1 months). The retrospective patient group was also prospectively followed using a standardized clinical and radiographic study design. RESULTS: The implant survival rate was 91.3% (63/69). All implants were lost during the period from abutment connection to connection of the definitive prosthesis. All bone grafts were stable. Bone grafts supported 48 implants, of which 5 failed (10.4%). In the residual bone, 21 implants were placed, of which 1 failed (4.8%). All patients received a fixed partial prosthesis, which was stable during the follow-up period. CONCLUSION: The results of this investigation revealed a satisfactory clinical outcome of implant placement in grafted partially dentate maxillae after a mean follow-up of 53.1 months.     

上颌窦内提升术用于严重骨萎缩患者种植修复3年疗效观察

目的：研究单纯上颌窦内提升术用于严重骨萎缩患者种植修复的临床疗效。方法：对2008～2009年上颌后牙缺失伴缺牙处余留骨高度不足5 mm的22例患者行单纯上颌窦内提升术,同期植入Straumann？？ SLA种植体32颗。术后6、12、24、36个月复查并行X线片检查。结果：所有种植体均于术后3~6个月成功负载,其中1颗种植体在负载12个月时脱落,其余种植体稳固,无相关并发症出现。种植体在36个月时的存留率为96.88%。术后6、12、24、36个月的根尖片显示,上颌窦内种植体周围骨高度持续稳定增加,36个月时骨高度增加 （3.41±0.42） mm,边缘骨丧失（1.21±0.46） mm。结论：单纯上颌窦内提升同期植入种植体,能有效解决上颌后牙区严重骨萎缩时的牙种植修复问题。     

Oral implants in combination with bone grafts. A 3-year retrospective multicenter study using the Br?nemark implant system.

A retrospective, multicenter, Scandinavian study of bone grafting of alveolar processes of severely atrophic jaws in combination with implant insertion was conducted with 150 patients. Five different grafting techniques were assessed: local or full onlay; inlay; combination of onlay/inlay grafts; and LeFort I osteotomies. The majority of the patients were treated using a one-stage approach (n = 125) and all had autogenous bone grafts. A total of 781 Br?nemark implants were inserted, of which 624 were placed in bone grafts and alveolar bone. Twenty-five patients (17%) dropped out during the follow-up period of three years. Within the remaining patients, 77% of the inserted implants (n = 516) were still in function at the end of the follow-up period. A further ten implants were kept mucosa-covered, resulting in an overall implant survival rate of around 80%. Onlays, inlays and LeFort I osteotomies showed almost the same success rates (76-84%), whereas the onlay/inlay technique gave rise to less favourable results (60%). Most of the observed losses (n = 131) took place during healing and the first year of loading. More implants were lost when they were inserted simultaneously with the grafting (23%) than when they were placed in a second stage (10%). The latter technique was used mainly in combination with local onlay grafting (16/25). The failure percentage for implants inserted in non-grafted bone (11%) was lower than for those inserted in bone grafts and alveolar bone (25%). The surviving implants of treated and followed patients served, in 88% of the cases (n = 110), to support fixed bridges or overdentures, albeit, in some instances (n = 23), after additional implant placement. In only 15 patients was it necessary to fall back on conventional removable prostheses or fixed partial bridges.     

Augmentation grafting of the maxillary sinus and simultaneous implant placement in patients with 3 to 5 mm of residual alveolar bone height.

This study assessed the efficacy of augmentation grafting of the maxillary sinus with simultaneous placement of dental implants in patients with less than 5 mm of alveolar crestal bone height in the posterior maxilla prior to grafting, although the procedure has traditionally been contraindicated based on empirical data. A total of 160 hydroxyapatite-coated implants was placed into 63 grafted maxillary sinuses in 63 patients whose crestal bone height in this region ranged from 3 to 5 mm. Patients were followed for 2 to 4 years after the placement of definitive prostheses. There were no postoperative sinus complications. Following uncovering of the implants at 9 months after surgery, there was no clinical or radiographic evidence of crestal bone loss around the implants. Histologic examination of bone cores from the grafted sites revealed successful integration and a high degree of cellularity. All patients maintained stable implant prostheses during follow-up. These findings indicate that the single-step procedure is a feasible option for patients with as little as 3 mm of alveolar bone height prior to augmentation grafting, utilizing hydroxyapatite-coated implants and autogenous bone.     

Bone grafting to the maxillary sinuses, nasal floor and anterior maxilla in the atrophic edentulous maxilla: A two-stage technique

This study presents the results from 20 consecutive patients treated with an autogenous bone graft from the iliac crest. In ten patients the graft was placed in the maxillary sinuses and the floor of the nose (inlay group). Ten patients, in addition to the inlay graft, had a corticocancellous bone block secured with mini-screws to the anterior maxillary ridge (inlay/onlay group). Endosteal implants (Brånemark^®) were placed six months after surgery. A total of 136 implants were placed, of which eight failed to integrate during the six-month healing period. A further 15 implants were lost during the follow-up period. For the inlay group the average follow-up period was 22 months and for the inlay/onlay group 19 months. Donor site morbidity was significantly less when iliac bone was harvested with a trephine (inlay group) than in patients treated with our routine procedure for bone harvesting (inlay/onlay group). Surgical technique, donor site morbidity, implant survival and patient acceptance are presented.     

Sinus lifting procedure. I. One-stage surgery with bone transplant and implants

A prospective study of one-stage surgery with intrasinus bone transplant and implants has been performed in 26 patients (13 males and 13 females). The aim of the study was to evaluate the success rate with the one-stage sinus lifting procedure in patients with a need for bony augmentation of the alveolar process. Fifteen patients were partially dentate and 11 edentulous. The mean height of the alveolar ridge was 2.5 mm preoperatively (range 1-5.5 mm). 126 fixtures were inserted, 93 in grafted bone and 33 in alveolar bone. Twenty-two patients have been followed for three years, 21 for four years and 11 for five years. The clinical overall survival rate was 69.6% although only 61.2% in grafted bone. Ten of the patients had varying degree of sinusitis post-fixture installation. At the end of the study, 23 patients had permanent bridges. The survival rate was low for inlay supported implants when the one-stage surgical technique was applied. Two-stage surgery may be a safer method.     

The 'mini'-implant has arrived

There is no question that dental implants have been the most influential change in dentistry during the last half-century. In general, they are well-proven and highly useful. However, the diameter of standard implants (approximately 3.75 mm), along with the frequent need to graft bone to allow for their placement, have limited their use for those who most need implants. The introduction, approval and continuing observation of success of smaller-diameter mini-implants have stimulated use of implants in situations in which standard-sized implants could not have been used without grafting. The result has been more patients who have been served successfully at reduced cost with minimized pain and trauma--patients who could not have been treated with implants otherwise. Continuing research is needed for further verification of the acceptability of mini-implants.     

Postoperative maxillary cyst following sinus bone graft: report of a case

Sinus bone grafting with autogenous bone is routinely performed to allow placement of endosseous dental implants. Although numerous maxillary sinuses have been successfully grafted, some complications of this procedure have been reported. These include maxillary sinusitis, resorption, infection and possible failure of grafts, loss of implants after 1-stage surgery, and oroantral fistulae. Only one case of postoperative maxillary cyst developing in the graft has been reported in the literature. Here, the authors report a similar case that necessitated grafting of the cyst with autologous iliac bone.     

Demineralized perforated bone implants in craniofacial surgery.

Between July 1990 and September 1991, demineralized perforated allogeneic bone implants (Pacific Coast Tissue Bank, Los Angeles, CA) were placed in 72 patients. Because many patients received more than one implant, a total of 248 implants were used in 80 procedures. The technology of processing demineralized bone implants is described in detail. All patients were operated on by one surgeon (K.E.S.) at the Humana Craniofacial Institute in Dallas, Texas. Forty-one patients had craniofacial deformities, 16 had secondary deformities following cleft lip and palate repair, 8 had bony defects following removal of tumors, and 10 had various skeletal deformities following trauma. Of the 72 patients, 6 had two surgical procedures during which additional implants were inserted. Implants placed in the cranial vault and the maxillary complex, including alveolar grafts, were inlay grafts, whereas implants placed in the orbital, nasal, paranasal, temporal, and malar areas were onlay grafts used for contouring, augmentation, or both. Complications were limited to delayed wound healing in 6 patients. According to our observations, demineralized perforated bone implants represent an encouraging alternative to autogenous bone grafting. Further clinical and experimental studies are necessary to obtain more information about this material.     

The use of autologous bone for augmentation procedures leads to low prevalence of peri-implantitis–a retrospective study over a 20-year period

The aim of this study was to compare the prevalence of peri-implantitis in implants inserted into pristine bone (control) to implants where autologous bone was used for grafting procedures (study).All patients who underwent implant surgery during a 20 years interval by one maxillofacial implant surgeon and received a prosthodontic rehabilitation afterwards were eligible for inclusion in the study. Periimplant bone resorption and periimplant disease were assessed.Of 421 patients 384 (91.2%) patients responded to a recall after having been treated over a 20-year period by one maxillofacial surgeon and several dentists. A total of 110 patients had 239 implants in pristine bone, and 274 patients had 607 implants placed in combination with autologous bone grafting procedures. Mean time in function was 74 months (range 15–236 months). In all, 342 implants (34.8%) were in function for longer than 7 years. A total of 64 implant sites (7.6%) in 39 patients (10.2%) showed signs of peri-implant mucositis. In addition, 17 implants (2.0%) in 14 patients (3.6%) revealed signs of peri-implantitis, of which five implants were in the control group (2.09%) whereas 12 implants were in the study group (1.98%), with no statistically significant difference (p = 0.8405). More than half of the patients with peri-implantitis had a history of periodontitis. Three implants were lost due to peri-implantitis and four implants failed for other reasons, resulting in an overall success rate of 99.2% in 846 implants.ConclusionsWithin the limitations of the study it seems that the use of autologous bone still is a relevant option when performing augmentation procedures because of the low prevalence of peri-implantitis.     

Reconstruction of an atrophied posterior mandible with the inlay technique and inorganic bovine bone block: a case report

A 53-year-old woman underwent bilateral reconstruction of her severely atrophic posterior mandible using inlay inorganic bovine bone block grafting. Four months later, a bone specimen was taken for histologic evaluation and eight dental implants were placed. These implants were loaded with a provisional prosthesis after another 4 months. When the definitive prosthesis was inserted 8 months postsurgery, all implants were osseointegrated. Histologic analysis showed that the grafted bone was lined with newly formed bone. The results indicate that inorganic bovine bone blocks might serve as an alternative to autogenous grafting for posterior mandibular augmentation using the inlay technique.     

Immediate function with the zygomatic implant: a graftless solution for the patient with mild to advanced atrophy of the maxilla

PURPOSE: In many edentulous maxillae, posterior alveolar atrophy calls for bone grafting. Patient treatment acceptance is increased by eliminating grafting using tilted implants, especially the zygomatic implant in combination with immediate function. The purpose of this study was to evaluate a protocol for immediate function (within 2 hours) of 2 zygomatic and 4 standard implants (Nobel Biocare) supporting a fixed prosthesis in the completely edentulous maxilla. MATERIALS AND METHODS: This clinical study included 14 patients with 83 immediately loaded implants (28 bilateral zygomatic and 55 premaxillary implants) supporting a complete maxillary denture converted to a fixed provisional prosthesis immediately following the surgical procedure. After 6 months of use, a new fixed metal-supported prosthesis was fabricated. RESULTS: Fourteen patients treated with immediate loading of zygomatic implants were followed for at least 12 months. All patients reported minimization of postoperative pain and security during speech, animation, and mastication. No failures occurred during the follow-up period. Discussion: The patients in the study could have been candidates for sinus grafting. With the present concept these patients benefited from a less invasive procedure (1 surgical procedure and no grafting) and immediate rehabilitation (prosthesis attached directly after surgery). CONCLUSION: The high survival rate, increase in patients' immediate functional ability, and reduction of morbidity following the surgical procedure render this procedure a viable treatment option for the completely edentulous maxilla.     

Implant treatment without bone grafting in edentulous severely resorbed maxillas: a long-term follow-up study.

PURPOSE: To evaluate retrospectively the surgical outcome of tilted implants in severely resorbed edentulous maxillas as an alternative to bone grafting and the prosthodontic outcome of posterior extension bridges on tilted implants. PATIENTS AND METHODS: A total of 33 consecutive patients with severely resorbed edentulous maxillas participated in the study. In these patients, the maxillary bone volumes were insufficient for conventional placement of implants to support a fixed prosthesis. As an alternative to bone transplantation, a surgical technique with fenestration of the maxillary sinus to visualize the total amount of maxillary bone was used, followed by implant placement in a tilted manner along the anterior maxillary sinus wall. Thus, 4 to 6 implants of optimal length could be installed in each patient. Nineteen patients were included in this long-term follow-up study and were eligible for clinical evaluation at 8 to 12 years (mean, 10 years) after second-stage surgery. Each patient was examined clinically and radiographically. RESULTS: The 19 patients had a total of 103 implants. In 2 of these patients, 3 fixtures were lost during the first year after second-stage surgery. All other patients had all implants intact with functionally fixed dental prostheses, corresponding to a success rate of 97%. Radiographic examination showed bone resorption in 10% of the implants (10 implants in 5 patients with a total number of 27 implants), with a mean bone loss of 1.2 mm. Mucositis was seen in 47% of the patients. CONCLUSIONS: This long-term follow-up study (mean time, 10 years) demonstrates that patients with a severely resorbed maxilla can be treated successfully with conventional implant treatment. This simplified surgical technique can be an alternative to the more resource-demanding technique with bone grafting.     

牙列缺损患者倾斜植入种植体稳定性的影响因素分析

临床上少数牙缺失患者缺牙部位牙槽骨存在严重吸收时,应用轴向种植需采用植骨或上颌窦底提升等方法,通过增加骨量以达到种植要求,但仍具有上颌窦黏膜穿孔或损伤下颌神经管的风险。一些临床医师采用倾斜种植方法以减少增骨手术的创伤,缩短修复期。倾斜植入的种植体的稳定性一直是关注的重点,本文收集近年来的相关文献,就影响倾斜植入稳定性的因素进行综述。     

Bone grafting of cleft lip and palate patients for placement of endosseous implants.

OBJECTIVE: Fixation of a prosthesis or single tooth replacement using osseointegrated implants has the potential to overcome functional and psychological inconveniences that many patients experience from such appliances. However, the dimensions of the recipient site are relatively often inadequate for implant placement. This study assessed grafting of this site with autogenous bone as a solution for the latter problem. METHODS: Ten cleft lip and palate patients had bone grafts; six had iliac crest grafts to the maxillary sinus floor (31 implants), and four had chin bone grafts to the local defect in the anterior maxilla (six implants). Implants were inserted during the grafting procedure (one patient) or after 3 months (nine patients). RESULTS: No inflammation of the bone grafts or the maxillary sinus occurred. One implant was lost during the healing phase. Four single tooth restorations, one fixed bridge, and five implant-supported overdentures were made. During the follow-up, which was 47 months (range, 28 to 65 months) in the anterior maxilla group and 56 months (range, 28 to 68 months) in the posterior maxilla group, no loss of implants was observed, and all prosthetic appliances functioned well. CONCLUSIONS: It is concluded that bone grafting followed by placement of dental implants can serve as a reliable alternative for conventional prosthetic rehabilitation of cleft patients.     

Bucco-lingual bone remodeling around implants placed into immediate extraction sockets: a case series

BACKGROUND: Implants placed immediately after tooth extraction have shown high percentages of clinical success. Few studies in the scientific literature have observed the horizontal bone remodeling in the buccal-lingual direction after immediate placement of implants. The aim of this study was to analyze bone healing and coronal bone remodeling around 15 implants placed immediately after tooth removal without the use of guided bone regeneration (GBR) techniques. METHODS: Ten patients received a total of 15 implants placed immediately after removal of 15 single-rooted teeth. All implants were placed within the alveolar confines, limiting, in most cases, small peri-implant bone defects. After implant placement, the distance from the buccal to lingual bone plate was measured. No membranes or filling materials were used. Primary flap closure was performed in all cases. RESULTS: At second-stage surgery, all peri-implant defects were completely filled and the distance from buccal to lingual bone was measured again. The pattern of bone healing around the neck of immediate implants showed an absence of peri-implant defects and a narrowing of bone crest width in a buccal-lingual direction. The mean distance between buccal bone and lingual bone at the time of implant placement was 10.5 mm (+/- 1.52) and, at second-stage surgery, 6.8 mm (+/- 1.33). CONCLUSIONS: The coronal bone remodeling around immediate implants showed a healing pattern with new bone apposition around the neck of the implants and, at the same time, bone resorption with horizontal width reduction of the bone ridge. The small peri-implant bone defects were completely healed without the use of GBR procedures. An absence of complications during the healing period was also observed, probably due to the absence of barrier membranes and grafting materials.     

Bone grafting and insertion of dental implants followed by Le Fort advancement for correction of severely atrophic maxilla in young patients

The atrophic maxilla often results in lateral, anteroposterior and vertical disproportion of the maxillary arches. This paper presents the case of a 40-year-old male with a severely atrophic maxilla who underwent oral rehabilitation. He was treated with onlay and inlay iliac bone grafts followed by vestibuloplasty and dental implant placement 170 days after initial bone grafting. The dental implants were uncovered after 4 months of healing. The patient also underwent orthognathic surgery for correction of the maxillary basal bone and to improve implant positioning. At the 48-month follow-up there were no complications.     

Implant treatment without bone grafting in severely resorbed edentulous maxillae.

PURPOSE: This article describes the surgical technique for implant treatment in severely resorbed edentulous maxillae without any alveolar reconstruction before or combined with implant placement. PATIENTS AND MATERIAL: Fifteen patients with severely resorbed edentulous maxillae were treated with osseointegrated implants and fixed dental prostheses. All patients were initially considered to be treated with bone grafting because of a lack of sufficient bone volume for conventional treatment. Preoperative radiographic examinations showed that the height of the alveolar crest was on average 7.4 mm at the 4-mm-width level (Classes V to VI). RESULTS: By fenestration of the maxillary sinus and uncovering the nasal floor, the maxillary bone could be visualized and used maximally for installation of implants. By angulation of the implants and permitting two to five uncovered fixture threads on the palatal aspect, implants of optimal length could be installed. Eighty-six implants were placed (four to six implants in every patient). One implant was lost during the observation time (range, 36 to 54 months; mean, 45 months). All patients had stable fixed prostheses at the end of the observation time. CONCLUSION: This cost-effective surgical technique may be considered as an alternative to more resource-demanding techniques such as bone grafting in patients with severely resorbed edentulous maxillae. However, further prospective comparative studies are necessary for full evaluation.