Retrospective clinical study of Osseotite implants: zero- to 5-year results

PURPOSE: Over the last few years, particular attention has been paid to the implant surface and its influence on the formation and maintenance of surrounding bone. The surface of Osseotite implants (Implant Innovations) is produced by a process of thermal etching, which produces a surface with an average roughness that is twice that of machined implants produced by the same manufacturer. In addition to reducing osseointegration time, this factor appears to favor its maintenance over time. This study presents the results of a clinical trial of Osseotite implants. MATERIALS AND METHODS: Five hundred fifty-five Osseotite implants were placed in 244 patients over 5 years, between September 1996 and September 2001. The average follow-up period from implant placement was 26 months (SD 13.1). RESULTS: After the first surgical stage, 8 failures were noted in 6 patients. Life table analysis showed a cumulative survival rate of 98.5%, but no implant was lost after prosthetic loading, with a 100% survival rate both for the mandible and for the maxilla. For the prosthetic loading time, only the implants with more than 12 months of loading were considered, obtaining an average prosthetic loading time of 34 months (SD 9.2). DISCUS SION: The implant survival rate after loading was 100% both in the anterior and posterior regions, and no difference was noted in relation to the different types of prostheses, or length and width of implants. CONCLUSION: The results obtained in this retrospective study population revealed an acceptable survival rate for these implant-supported restorations.     

A meta-analysis examining the clinical survivability of machined-surfaced and osseotite implants in poor-quality bone

PURPOSE: A frequently cited cause of dental implant failure is the inadequate quality of bone found at the implant site during osteotomy preparation. Although bone quality clearly can affect integration rates, additional variables, such as the implant surface conditioning, can also influence long-term implant performance success. The following report examines outcomes of clinical studies that monitored the performance of machined-surfaced implants and dual acid-etched Osseotite (Implant Innovations, Inc., Palm Beach Gardens, FL) implants isolating the effect of bone quality and implant surface conditioning. MATERIALS AND METHODS: Implant data are derived from eight prospective multicenter clinical studies representing 2614 machined-surfaced implants and 2288 Osseotite implants. All implant placement surgeries followed a two-stage surgical approach with an unloaded healing period of 4 to 6 months. Bone quality was assessed by operator perception of resistance during drilling and ranked as dense, normal, or soft. At the time of this analysis, implant follow-up from placement ranged up to 66 months for the Osseotite and 84 months for the machined-surfaced implants. To isolate the effect of bone quality, other baseline variables were compared to ensure equal distribution between groups. Baseline variables included patient demographics, locations, dimensions of implants, and types of restorative cases. Implant performance was analyzed using nonparametric survival analysis (Kaplan-Meier estimator). Cumulative success rates (CSR) were calculated and differences between implant-bone quality combinations were assessed using the log-rank method. RESULTS: For the machined-surfaced implants, the 4-year CSR in all bone sites is 92.7%. For the implants placed in good (dense and normal) bone, the 4-year CSR is 93.6% compared with the 4-year CSR in poor (soft) bone of 88.2% (P < 0.05). For Osseotite implants in all sites, their overall 4-year CSR was 98.4%, 98.4% in good bone, and 98.1% in poor bone. CONCLUSIONS: Bone quality therefore seems to have a definitive impact on machined-surfaced implants, but this effect was not observed in the Osseotite implant series.     

Clinical evaluation of dental implants with surfaces roughened by anodic oxidation, dual acid-etched implants, and machined implants

PURPOSE: The purpose of this study was the clinical and radiographic comparison of dental implants with surfaces roughened by anodic oxidation (TiUnite), dual acid-etched implants (Osseotite), and machined implants. MATERIALS AND METHODS: Seventy-four patients (mean age, 52.8 +/- 14.2 years; range, 23 to 80 years; 41 men and 33 women) received 198 dental implants-58 TiUnite implants (25 patients), 52 Osseotite implants (27 patients), and 88 machined implants (22 patients). Clinical measurements and radiographs were evaluated at the time of surgery, at the restorative phase, and 2 years postloading. To account for statistical correlation among multiple implants in the same subject, a "per patient" mode of analysis was conducted. A 1-way analysis of variance of bone loss was conducted by type of implant as well by area of the mouth. In addition, differences in mean bone loss were tested for bone density category, gender, and smoking status using Student t tests. RESULTS: Eighteen TiUnite implants (31.0%) were placed in the maxilla and 40 (69.0%) in the mandible. The Osseotite group included 29 maxillary implants (55.8%) and 23 mandibular implants (44.2%). The machined group included 49 maxillary implants (55.7%) and 39 mandibular implants (44.3%). All 198 implants were considered radiographically and clinically successful. No mobility, signs of infection, or inflammation were detected. DISCUSSION: Implant size, location, bone quality, gender, age, and smoking did not influence the comparative clinical outcomes of the 3 groups (P > .05). A trend toward greater coronal bone loss in the TiUnite group was detected. CONCLUSION: Within the limitations of the present study, TiUnite, Osseotite, and machined dental implants had similar short-term clinical outcomes. No statistically significant differences in bone loss could be detected among implant groups or among the different regions of the oral cavity. The present data underlined the significance of surgical and prosthetic treatment planning.     

Osseointegration of Osseotite and machined titanium implants in autogenous bone graft. A histologic and histomorphometric study in dogs

It has been shown that a roughened implant surface results in a higher percentage of bone to implant contact (%BIC) than a machined one. A modified implant surface using a dual thermo-acid etching process (Osseotite) has been introduced and evaluated clinically, mechanically and histologically. The aim of the present study was the histological evaluation of the %BIC between the Osseotite or machined surfaces and the autogenous bone graft. Twenty-two custom-made split-type 10-mm-long implants having two opposing surfaces (Osseotite and machined) were placed between the cranial and caudal dorsal iliac spine at the iliac wing of two adult mongrel dogs. An artificial bone defect was created leaving a 2 mm empty space around the coronal 5 mm of the implants, while the apical 5 mm was stabilized in the existing basal bone. The defects around the implants were filled with particulate autogenous bone graft, covered by an Osseoquest membrane, and left to heal for 5 months. All inserted implants showed a complete integration in the bone tissue. It was found that the resulting %BIC at the Osseotite surface was significantly higher than at the machined one in both regenerated (46.44+/-15.81% vs. 28.59+/-12.04%) and basal bone areas (32.32+/-15.09% vs. 17.25+/-7.40%). The findings of this study imply that the use of autogenous bone graft resulted in significantly higher %BIC values in the regenerated area than in the basal bone area itself, for both implant surfaces.     

Surface characteristics of electrochemically oxidized implants and acid-etched implants: surface chemistry, morphology, pore configurations, oxide thickness, crystal structure, and roughness

PURPOSE: This study was undertaken to investigate surface properties of surface-modified titanium implants in terms of surface chemistry, morphology, pore characteristics, oxide thickness, crystal structure, and roughness. MATERIALS AND METHODS: An oxidized, custom-made Mg implant, an oxidized commercially available implant (TiUnite), and a dual acid-etched surface (Osseotite) were investigated. Surface characteristics were evaluated with various surface analytic techniques. RESULTS: Surface chemistry showed similar fingerprints of titanium oxide and carbon contaminant in common for all implants but also revealed essential differences of the elements such as about 9 at% Mg for the Mg implant, about 11 at% P for the TiUnite implant and about 12 at% Na for the Osseotite implant. Surface morphology of the Mg and TiUnite implants demonstrated a duplex oxide structure, ie, an inner barrier layer without pores and an outer porous layer with numerous pores, whereas the Osseotite implant revealed a crystallographically etched appearance with pits. The diameter and depth of pores/pits was < or = 2 microm and < or = 1.5 microm in the Mg implant, < or = 4 microm and < or = 10 microm in the TiUnite implant, and < or = 2 microm and < or = 1 microm in the Osseotite implant, respectively. Oxide layer revealed homogeneous thickness, about 3.4 microm of all threads in the Mg implants. On the contrary, TiUnite showed heterogeneous oxide thickness, about 1 to 11 microm, which gradually increased with thread numbers. Crystal structure showed a mixture of anatase and rutile phase for the Mg implants. With respect to roughness, Sa showed 0.69 microm in the Mg implant, 1.35 microm in the TiUnite implant, and 0.72 microm in the Osseotite implant. CONCLUSIONS: Well-defined surface characterization may provide a scientific basis for a better understanding of the effects of the implant surface on the biological response. The surface-engineered implants resulted in various surface characteristics, as a result of different manufacturing techniques.     

A prospective multicenter study evaluating loading of osseotite implants two months after placement: one-year results.

Historically, the recommended time between placement and functional loading of machined-surface dental implants has been 3 months for the mandible and 6 months for the maxilla. However, such recommendations are a result of evaluating randomly chosen healing times during the initial phase of implant development and are based on the subsequent clinical outcome of either implant integration or mobility. In recent years, histologic and experimental studies have shown that specifically designed micro-topographic implant surfaces can result in increased bone-to-implant contact at earlier healing times than obtained with machined-surface implants. Histologic and clinical studies investigating early and immediate implant loading support the premise that implants can be placed into function earlier than previously recommended. With the development of specifically designed implant surfaces and the utilization of time-saving surgical (one-stage surgical protocol) and prosthetic (implant position indexing) techniques, patients are now being restored and returning to function sooner than previously thought possible. The purpose of this multicenter clinical investigation is to evaluate the efficacy of loading Osseotite dental implants (3i-Implant Innovations Inc., Palm Beach Gardens, Florida) at 2 months and to determine the effect of early loading on implant performance and survival. A total of 429 Osseotite implants were placed in 155 patients (87 females and 68 males; mean age 54.0 +/- 13.7 yr), at 10 study centers, and subsequently loaded 2.1 +/- 0.7 months following placement. A single-stage surgical protocol was followed, with implants indexed immediately or impressed 4 to 6 weeks following placement. Patient restorative treatments included placement of 83 single-implant provisional restorations and 129 splinted, two-, three-, and four-implant supported maxillary and mandibular provisional restorations. The mean time from prosthetic loading to the most recent follow-up evaluation was 10 +/- 1.3 months. Seven of the 429 implants did not integrate; of these, six were identified prior to loading and one was identified 1 month after loading. The cumulative implant survival rate was 98.5% at 12.6 months. The cumulative post-loading implant survival rate was 99.8% at 10.5 months. The preliminary results of this clinical investigation suggest that successful functional loading of the Osseotite dental implant is possible at 2 months following noncomplicated implant placement.     

A human histologic analysis of osseotite and machined surfaces using implants with 2 opposing surfaces

A human histologic study was conducted to compare the percentage of bone-to-implant contact (BIC) at 6 months for Osseotite and machined, commercially pure titanium implant surfaces. To eliminate potential influences caused by differences in bone density at different intraoral locations, 2 mm x 5 mm, threaded, 2-surfaced titanium implants were manufactured; 1 side received the Osseotite surface modification and the opposite side maintained a machined surface. In each of 11 patients, 1 test implant was placed in the posterior maxilla (Types III and IV bone) during conventional dental implant surgery. Following 6 months of unloaded healing, the conventional implants were uncovered, and the test implants and surrounding hard tissue were removed. Histologic analysis indicated that at 6 months of unloaded healing, the mean BIC value for the Osseotite surfaces (72.96% +/- 25.13%) was statistically significantly higher (P < 0.05) than the mean BIC value for the machined surfaces (33.98% +/- 31.04%). When the BIC values for the machined and Osseotite surface pairs were ranked from high to low based on the machined BIC value range of 93% to 0%, the upper 50th percentile (20 surface pairs) mean BIC value was 86.1% +/- 16.7% for the Osseotite surfaces and 60.1% +/- 18.3% for the machined surfaces. The lower 50th percentile (19 surface pairs) mean BIC value was 59.1% +/- 25.3% for the Osseotite surfaces and 6.5% +/- 10.8% for the machined surfaces. Differences between mean BIC values for the 2 surfaces in both the upper and lower 50th percentiles were statistically significant (P < 0.05). The results of this study indicate that in the poorer quality bone typically found in the posterior maxilla, a statistically significantly higher percentage of bone contacts Osseotite surfaces when compared to opposing machined surfaces on the same implant.     

Surface characterization of three titanium dental implants

PURPOSE: The aim of this study was to evaluate topographically and compositionally the rough surface of 3 different commercial titanium dental implants. MATERIALS: Bio Com Standard, Osseotite Implant, and Fixture MT Osseospeed were analyzed using scanning electron microscopy, atomic force microscopy, and energy dispersive spectroscopy. RESULTS: The scanning electron microscopy and atomic force microscopy analyses showed that the rough surface of Bio Com Standard presents numerous impressions superimposed by sharp pits, of Osseotite Implant many discrete sharp pits, and of Fixture MT Osseospeed a mixed feature appearance. The energy dispersive spectroscopy analysis of the rough implant surfaces revealed a small trace of Si found on the surface of Osseotite Implant. Fixture MT Osseospeed showed a nonhomogeneous distribution of the detected elements. CONCLUSION: The examined implants had a different rough surface topography, which was directly dependent on the type of treatment used. The differences concerning the surface morphology were leading in a characteristic nanotopography, which might influence the biologic activities at the implant-tissue interface. Surface oxygen concentrations also indicated differences in the oxide layer width between the examined implants, being minimal in Osseotite Implant and maximal in Fixture MT Osseospeed.     

Early bone formation around immediately loaded FBR-coated implants after 8, 10 and 12 weeks: a human histologic evaluation of three retrieved implants

The surface characteristics of dental implants play an important role in the osseointegration process. Over the years implant surfaces have been subjected to different treatments, including turning, plasma spraying, coating, sand blasting, acid etching, and anodization. FBR coating is a fully resorbable calcium phosphate (CaP) coating made of brushite, obtained by electrochemical deposition on titanium plasma-sprayed (TPS) implants; this bioactive layer may be totally resorbable in 6-12 weeks and once the FBR coating has been resorbed, the newly formed bone is in contact with the roughness of the TPS surface. Human biopsy of immediately-loaded implants is certainly the most definitive means of determining the occurrence of osseointegration. In this case series the histologic and histomorphometric features of the bone-implant interface are analyzed and discussed in 3 immediately restored implants, retrieved from human subjects at 8, 10 and 12 weeks, respectively. All 3 implants were osseointegrated, with a bone to implant contact (BIC) ranging from 54.4% to 70.1%. The FBR coating was resorbed and replaced by new bone. Osteoconduction was especially noticeable between the implant threads, where the pristine bone was removed during implant bed preparation. The results suggest that the resorption window of 6-12 weeks for the CaP coating seems to be confirmed at least in the human mandible, and that immediately loaded FBR-coated implants placed in the posterior mandible can achieve osseointegration within 6-12 weeks of loading.     

Surface treatments of titanium dental implants for rapid osseointegration.

The osseointegration rate of titanium dental implants is related to their composition and surface roughness. Rough-surfaced implants favor both bone anchoring and biomechanical stability. Osteoconductive calcium phosphate coatings promote bone healing and apposition, leading to the rapid biological fixation of implants. The different methods used for increasing surface roughness or applying osteoconductive coatings to titanium dental implants are reviewed. Surface treatments, such as titanium plasma-spraying, grit-blasting, acid-etching, anodization or calcium phosphate coatings, and their corresponding surface morphologies and properties are described. Most of these surfaces are commercially available and have proven clinical efficacy (>95% over 5 years). The precise role of surface chemistry and topography on the early events in dental implant osseointegration remain poorly understood. In addition, comparative clinical studies with different implant surfaces are rarely performed. The future of dental implantology should aim to develop surfaces with controlled and standardized topography or chemistry. This approach will be the only way to understand the interactions between proteins, cells and tissues, and implant surfaces. The local release of bone stimulating or resorptive drugs in the peri-implant region may also respond to difficult clinical situations with poor bone quality and quantity. These therapeutic strategies should ultimately enhance the osseointegration process of dental implants for their immediate loading and long-term success.     

构建牙科种植体抗摩擦磨损表面微结构的可行性分析

钛及钛合金由于具有良好的生物相容性和机械性能,是目前商品化牙科种植体的首选基材.然而其表面极易生成氧化膜,该膜机械强度不足,受力易剥脱,使得表层材料容易发生摩擦磨损.为克服这一问题目前所有品牌种植体的表面都进行了大颗粒酸蚀喷砂或阳极氧化等处理,以形成更加稳定的且易于成骨细胞附着的表面.但仍有临床研究发现,种植体在植入过...     

Measurements comparing the initial stability of five designs of dental implants: a human cadaver study

Background: A number of different dental implant designs are currently in clinical use. A successful outcome of implant placement is thought, at least in part, to be due to the primary stability of an implant after placement. Few data are available for comparing the primary stability characteristics of different implant designs. Purpose: This investigation compared the primary stability of five types of endosseous dental implant of varying geometry and surface topography. Materials and Methods: Comparison was made between a standard threaded commercially pure titanium implant (Nobel Biocare AB, Göteborg, Sweden), the Mark II self‐tapping implant (Nobel Biocare AB, Göteborg, Sweden), the Mark IV tapered self‐tapping implant (Nobel Biocare AB, Göteborg, Sweden), the Astra Tioblast (AstraTech AB, Mölndahl, Sweden), and the 3i Osseotite (3I [Implant Innovations Incorporated], Palm Beach, Florida, USA). Fifty‐two fixtures were placed in the maxillary bone of nine unembalmed human cadavers. Implant stability as a function of peak insertion torque and resonance frequency values was recorded for each fixture site after placement. Removal torque was also measured 1‐hour postinsertion. Assessment of bone quality at each site was made. Results: All of the implants tested demonstrated good primary stability in type 2 and 3 bone. The Standard, Mark II, Osseotite, and Tioblast were less stable when placed into bone type 4. The Mark IV implants appeared to maintain a high primary stability even in Type 4 bone. Conclusion: When looking across all bone qualities, the Mark IV implant develops a significantly higher insertion torque than the Standard, Mark II, and Osseotite implant types, and a significantly higher resonance frequency value than the Standard implant, indicating a higher interfacial stiffness at the implant–bone interface.     

Evaluating the clinical performance of the Osseotite implant: defining prosthetic predictability

A 5-year prospective, multicenter study is in progress at four private dental practices to determine the cumulative implant survival rate and prosthetic outcome when using the Osseotite dental implant in posterior maxillary and mandibular areas. An interim evaluation after 34.4 months of study progress is presented. A total of 219 Osseotite implants were placed in 74 patients (34 women and 40 men with a mean age of 57.8 +/- 15.2 years) using a conventional two-stage surgical protocol and 3- to 6-month healing time. Subsequently, patients were restored with fixed or removable restorations. Nineteen of the 74 patients reported smoking an average of 13.2 cigarettes per day. Restorative treatments included 40 single-unit restorations; 53 splinted 2-, 3-, 4-, and 5-unit implant-supported maxillary and mandibular prostheses; 4 full-arch fixed maxillary prostheses; 1 mandibular fixed/detachable hybrid prosthesis; and 1 mandibular overdenture. The mean time from implant placement to second stage surgery was 6.2 +/- 2.0 months; from restoration and implant loading to the most recent follow-up evaluation was 20.9 +/- 6.8 months. Of the 219 implants placed, three posterior maxillary implants developed infections and were removed prior to second stage surgery. No implant failures occurred at second stage surgery or after implant loading. Using the Kaplan-Meier method, the cumulative implant survival rate was 100% for anterior implants and 98.4% for posterior implants at 28.5 +/- 5.7 months. The cumulative postloading implant survival rate was 100% for both anterior and posterior implants. The results of this study indicate that the Osseotite dental implant achieved a high rate of integration that remained stable during nearly 2 years of implant function. In addition, because no postloading implant failures have occurred, the Osseotite implant has provided a high level of prosthetic predictability.     

Healing of Osseotite implants under submerged and immediate loading conditions in a single patient: a case report and interface analysis after 2 months

A growing number of clinical studies show that early (2 months) and immediate loading protocols may be predictable. However, they are based on clinical stability only The aim of this case report was to document the osseointegration status of two Osseotite implants after 2 months of healing in soft bone corresponding to type IV and subjected to two distinct mechanical environments. A completely edentulous patient received a total of 11 Osseotite implants in the mandible. Six were immediately loaded to support a provisional fixed partial denture, and five were left submerged. After 2 months, two submerged and one immediately loaded implants were retrieved and processed for histologic analysis. All immediately loaded implants were clinically stable. One histologic section per implant was obtained. All implants achieved osseointegration. The bone-implant contact was 38.9% for the submerged implant and 64.2% for the immediately loaded one. In the marrow space, both implants were covered by thin, neoformed bone trabeculae. Osseointegration can be achieved after 2 months by Osseotite implants placed in soft bone in the mandible either when immediately loaded and splinted into a provisional denture retained on six implants, or when submerged and unloaded.     

A Prospective Multicenter Study Evaluating Loading of Osseotite Implants Two Months After Placement: One-Year Results

Abstract: Historically, the recommended time between placement and functional loading of machined-surface dental implants has been 3 months for the mandible and 6 months for the maxilla. However, such recommendations are a result of evaluating randomly chosen healing times during the initial phase of implant development and are based on the subsequent clinical outcome of either implant integration or mobility. In recent years, histologic and experimental studies have shown that specifically designed micro-topographic implant surfaces can result in increased bone-to-implant contact at earlier healing times than obtained with machined-surface implants. Histologic and clinical studies investigating early and immediate implant loading support the premise that implants can be placed into function earlier than previously recommended. With the development of specifically designed implant surfaces and the utilization of time-saving surgical (one-stage surgical protocol) and prosthetic (implant position indexing) techniques, patients are now being restored and returning to function sooner than previously thought possible. The purpose of this multicenter clinical investigation is to evaluate the efficacy of loading Osseotite dental implants (3i-Implant Innovations Inc., Palm Beach Gardens, Florida) at 2 months and to determine the effect of early loading on implant performance and survival. A total of 429 Osseotite implants were placed in 155 patients (87 females and 68 males; mean age 54.0 ± 13.7 yr), at 10 study centers, and subsequently loaded 2.1 ± 0.7 months following placement. A single-stage surgical protocol was followed, with implants indexed immediately or impressed 4 to 6 weeks following placement. Patient restorative treatments included placement of 83 single-implant provisional restorations and 129 splinted, two-, three-, and four-implant supported maxillary and mandibular provisional restorations. The mean time from prosthetic loading to the most recent follow-up evaluation was 10 ± 1.3 months. Seven of the 429 implants did not integrate; of these, six were identified prior to loading and one was identified 1 month after loading. The cumulative implant survival rate was 98.5% at 12.6 months. The cumulative post-loading implant survival rate was 99.8% at 10.5 months. The preliminary results of this clinical investigation suggest that successful functional loading of the Osseotite dental implant is possible at 2 months following noncomplicated implant placement.     

Immediate provisional restoration of Osseotite implants: a clinical report of 18-month results

PURPOSE: The purpose of this study was to assess the survival rates and interproximal bone levels for Osseotite implants that were restored with fixed provisional crowns without occlusion immediately after implant placement. MATERIALS AND METHODS: Ninety-three implants were placed in 38 partially edentulous patients. All implants were immediately restored with prefabricated abutments and cement-retained provisional crowns without centric or eccentric occlusal contacts. The implants were restored with definitive restorations approximately 8 to 12 weeks after implant placement. All patients included in the study were followed for at least 18 months after implant placement (average 20.3 months). RESULTS: Seventy-seven of the 93 implants satisfied the inclusion criteria. Seventy-five implants became osseointegrated. The overall survival rate was 97.4%. Radiographic bone loss 18 months after implant placement (the mean of both interproximal surfaces) was 0.76 mm. The exact binomial confidence interval was 0.32% to 9.07%. For the exact binomial test with the null hypothesis proportion = .05, P was .3334 and was not statistically significant. DISCUSSION: Immediate nonocclusal loading of single-unit dental implants differs from immediate loading of multiple, splinted implants. Unsplinted, restored implants without occlusal loading may still be subject to lateral and occlusal loads secondary to the proximate location of the food bolus. Immediate restoration of dental implants significantly reduces treatment time and may be beneficial in reducing the morbidity associated with loss of teeth, contraction of the alveolus, and loss of interdental papillae associated with the traditional method of treatment following tooth loss. CONCLUSIONS: The results of this study suggest that immediate restoration of Osseotite implants can be accomplished with results that are similar to the results obtained with the traditional 1- or 2-stage surgical, unloaded healing protocols.     

Comparison of bioactive glass coated and hydroxyapatite coated titanium dental implants in the human jaw bone

Background: Current trends in clinical dental implant therapy include modification of titanium surfaces for the purpose of improving osseointegration by different additive (bioactive coatings) and subtractive processes (acid etching, grit‐blasting). The aim of this study was to evaluate and compare the behaviour of hydroxyapatite and the newly developed bioactive glass coated implants (62 implants) in osseous tissue following implantation in 31 patients. Methods: Bioactive glass and hydroxyapatite was suitably coated on titanium alloy. Hydroxyapatite coating was applied on the implant surface by air microplasma spray technique and bioactive glass coating was applied by vitreous enamelling technique. The outcome was assessed up to 12 months after prosthetic loading using different clinical and radiological parameters. Results: Hydroxyapatite and bioactive glass coating materials were non‐toxic and biocompatible. Overall results showed that bioactive glass coated implants were as equally successful as hydroxyapatite in achieving osseointegration and supporting final restorations. Conclusions: The newly developed bioactive glass is a good alternative coating material for dental implants.     

Immediate loading of osseotite implants: two-year results

The high success rate of dental implants has changed the quality of life for many patients. Immediate loading finds its application in some clinical cases and certainly adds another modality of treatment for the implant patient. Starting with a couple of implants placed in the mandible and immediately loaded within 72 hours after surgical placement with an overdenture, this concept evolved to immediately loading multiple implants in both the maxilla and the mandible. In this investigation, 11 consecutive patients were treated with 87 screw-shaped endosteal acid-etched, Osseotite implants (3i, Implant Innovations, Inc., Palm Beach Gardens, FL) between June 1998 and June 1999. Two mandibular and two maxillary cases received screw-retained provisional prostheses the day of surgery. Three mandibular and four maxillary cases were loaded 48 hours after surgery with the final screw-retained, porcelain-fused-to-metal prostheses. All implants were followed for 2 to 3 years. Follow-up consisted of clinical as well as radiographic examination. All implants were successful. There was no implant mobility or periimplant radiolucency. The bone level was measured at the 12th and 24th months. The average radiographic bone level from the implant platform to the first bone-to-implant contact was 0.654 mm at the 12th month and 0.946 mm at the 24th month. We conclude that a high success rate can be achieved when implants with a hybrid surface, machined/acid-etched, are immediately loaded within 48 hours after surgical placement in the maxilla and the mandible.     

Immediate loading of Osseotite implants: a case report and histologic analysis after 4 months of occlusal loading.

A growing number of clinical reports show that early and immediate loading of endosseous implants may lead to predictable osseointegration; however, these studies provide mostly short- to mid-term results based only on clinical mobility and radiographic observation. Other methods are needed to detect the possible presence of a thin fibrous interposition of tissue that could increase in the course of time and lead to clinical mobility A histologic evaluation was performed on two immediately loaded Osseotite implants retrieved after 4 months of function from one patient. He had received a total of 12 implants in the mandible, of which six were immediately loaded and six were left to heal in a submerged way Clinical and histologic osseointegration was consistently achieved for both of the retrieved immediately loaded implants. Osteogenesis and bone remodeling on the Osseotite surface were not impeded by immediate loading as shown by histomorphometric evaluation, which revealed high levels of bone-to-implant contact ranging from 78% to 85%. This immediate loading protocol involving bilateral splinting of six Osseotite implants in the mandible proved to be successful after 4 months of loading. Further long-term clinical and histologic studies are needed before introducing this immediate loading protocol as a routine procedure in implant therapy.     

Surface analysis of machined versus sandblasted and acid-etched titanium implants

Initially, implant surface analyses were performed on 10 machined implants and on 10 sandblasted and acid-etched implants. Subsequently, sandblasted and acid-etched implant cytotoxicity (using L929 mouse fibroblasts), morphologic differences between cells (osteoblast-like cells MG63) adhering to the machined implant surfaces, and cell anchorage to sandblasted and acid-etched implant surfaces were evaluated. Results indicated that acid etching with 1% hydrofluoric acid/30% nitric acid after sandblasting eliminated residual alumina particles. The average roughness (Ra) of sandblasted and acid-etched surfaces was about 2.15 microns. Cytotoxicity tests showed that sandblasted and acid-etched implants had non-cytotoxic cellular effects and appeared to be biocompatible. Scanning electron microscopic examination showed that the surface roughness produced by sandblasting and acid etching could affect cell adhesion mechanisms. Osteoblast-like cells adhering to the machined implants presented a very flat configuration, while the same cells adhering to the sandblasted and acid-etched surfaces showed an irregular morphology and many pseudopodi. These morphologic irregularities could improve initial cell anchorage, providing better osseointegration for sandblasted and acid-etched implants.