Clinical experiences with laser-welded titanium frameworks supported by implants in the edentulous mandible: a 10-year follow-up study

Background: Long‐term follow‐up studies for more than 5 years are not available on laser‐welded titanium frameworks. Purpose: To report and compare 10‐year data on implant‐supported prostheses in the edentulous mandible provided with laser‐welded titanium frameworks and conventional gold alloy frameworks. Materials and Methods: Altogether, 155 patients were consecutively treated with prostheses at abutment level with two generations of fixed laser‐welded titanium frameworks (test groups). A control group of 53 randomly selected patients with conventional gold alloy castings was used for comparison. Clinical and radiographic 10‐year data were collected for the three groups. Results: All patients followed‐up for 10 years (n=112) still had fixed prostheses in the mandible (cumulative success rate CSR] 100%). The overall 10‐year cumulative success rate (CSR) was 92.8 and 100.0% for titanium and gold alloy frameworks, respectively. Ten‐year implant cumulative survival rate (CSR) was 99.4 and 99.6% for the test and control groups, respectively. Average 10‐year bone loss was 0.56 (SD 0.45) mm for the titanium group and 0.77 (SD 0.36) mm for the control group (p < 0.05). The most common complications for titanium frameworks were resin or veneer fractures, soft tissue inflammation, and fractures (12.9%) of the metal frame. Loose and fractured implant screw components were below 3%. Conclusion: Excellent overall long‐term results with 100% CSR could be achieved with the present treatment modality. Fractures of the metal frames and remade prostheses were more common for the laser‐welded titanium frameworks, and the first generation of titanium frameworks worked poorly when compared with gold alloy frameworks during 10 years (p < 0.05). However, on average more bone loss was observed for implants supporting gold alloy frameworks during 10 years. The reasons for this difference are not clear.     

Early laser-welded titanium frameworks supported by implants in the edentulous mandible: a 15-year comparative follow-up study

Background: Comparative long‐term knowledge of different framework materials in the edentulous implant patient is not available for 15 years of follow‐up. Purpose: To report and compare a 15‐year retrospective data on implant‐supported prostheses in the edentulous mandible provided with laser‐welded titanium frameworks (test) and gold alloy frameworks (control). Materials and Methods: Altogether, 155 patients were consecutively treated with abutment‐level prostheses with two early generations of fixed laser‐welded titanium frameworks (titanium group). Fifty‐three selected patients with gold alloy castings formed the control group. Clinical and radiographic 15‐year data were collected and compared for the groups. Results: All patients who were followed up for 15 years (n = 72) still had a fixed prosthesis in the mandible at the termination of the study. The 15‐year original prosthesis cumulative survival rate (CSR) was 89.2 and 100% for titanium and control frameworks (p = .057), respectively (overall CSR 91.7%). The overall 15‐year implant CSR was 98.7%. The average 15‐year bone loss was 0.59 mm (SD 0.56) and 0.98 mm (SD 0.64) for the test and control groups (p = .027), respectively. Few (1.3%) implants had >3.1‐mm accumulated bone loss after 15 years. The most common complications for titanium frameworks were resin or veneer fractures and soft tissue inflammation. Fractures of the titanium metal frame were observed in 15.5% of the patients. More patients had framework fractures in the earliest titanium group (Ti‐1 group) compared to the gold alloy group (p = .034). Loose and fractured implant screw components were few (2.4%). Conclusion: Predictable overall long‐term results could be maintained with the present treatment modality. Fractures of the metal frames and remade prostheses were more common in the test group, and the gold alloy frameworks had a tendency to work better when compared with welded titanium frameworks during 15 years. However, on the average, more bone loss was observed for implants supporting gold alloy frameworks.     

CNC‐Milled Titanium Frameworks Supported by Implants in the Edentulous Jaw: A 10‐Year Comparative Clinical Study

Background: No long‐term clinical studies covering more than 5 years are available on Computer Numeric Controlled (CNC) milled titanium frameworks. Aim: To evaluate and compare the clinical and radiographic performance of implant‐supported prostheses provided with CNC titanium frameworks in the edentulous jaw with prostheses with cast gold‐alloy frameworks during the first 10 years of function. Material and Methods: Altogether, 126 edentulous patients were by random provided with 67 prostheses with titanium frameworks (test) in 23 maxillas and 44 mandibles, and with 62 prostheses with gold‐alloy castings (control) in 31 maxillas and 31 mandibles. Clinical and radiographic 10‐year data were collected for the groups and statistically compared on patient level. Results: The 10‐year prosthesis and implant cumulative survival rate was 95.6% compared with 98.3%, and 95.0% compared with 97.9% for test and control groups, respectively (p > .05). No implants were lost after 5 years of follow‐up. Smokers lost more implants than nonsmokers after 5 years of follow‐up (p < .01). Mean marginal bone loss in the test group was 0.7 mm (SD 0.61) and 0.7 mm (SD 0.85) in the maxilla and mandible, with similar pattern in the control group (p > .05), respectively. One prosthesis was lost in each group due to loss of implants, and one prosthesis failed due to framework fracture in the test group. Two metal fractures were registered in each group. More appointments of maintenance were needed for the prostheses in the maxilla compared with those in the mandible (p < .001). Conclusion: The frequency of complications was low with similar clinical and radiological performance for both groups during 10 years. CNC‐milled titanium frameworks are a viable alternative to gold‐alloy castings for restoring patients with implant‐supported prostheses in the edentulous jaw.     

Complications in partially edentulous implant patients: a 5-year retrospective follow-up study of 133 patients supplied with unilateral maxillary prostheses

Background: Numerous studies have reported successful outcomes for restoration of fully endentulous patients with Brånemark implants. However, some studies indicate more mechanical problems in restored partially endentulous situations. Purpose: The objective was to study patients with potential risk for mechanical complications after implant treatment. Materials and Methods: Patients were retrospectively evaluated 5 years after implant treatment in upper jaw Appelgate-Kennedy Class II situations. Altogether 422 implants ad modum Brånemark were installed in 137 consecutively treated patients. One hundred thirty-three prostheses were placed and followed-up for 5 years, according to routine clinical protocols. Results: The overall 5-year implant cumulative survival rate (CSR) was 94.0%. The corresponding CSR for loaded implants and prostheses was 97.7% and 98.4%, respectively, and the overall marginal bone loss was 0.8 mm (0.6 mm) after 5 years. Sixteen abutment screws fractured in seven patients (5%) and 17 prostheses (13%) presented loose abutment or gold screws during the follow-up period. Significantly more problems were reported in association with prostheses that included the canine (p <.05), and significantly more gold screws were working loose when only two implants were supporting the frameworks (p<.01). Conclusions: Upper jaw implant treatment in unilateral free-end situations seems to involve more mechanical problems than other implant treatment groups when only two implants can be installed and when the canine tooth is missing. However, most of these complications are easily adjusted, and the clinical survival of implants and prostheses is the same for these groups compared to other groups of partially edentulous implant patients.     

Clinical experiences of CNC-milled titanium frameworks supported by implants in the edentulous jaw: 1-year prospective study

Background: A new type of titanium framework has been introduced, but so far no clinical reports have been made in this treatment modality. Purpose: The aim of this study was to report the clinical performance of implant‐supported prostheses with computer numeric controlled (CNC)‐milled titanium frameworks in the edentulous jaw and to compare the results with prostheses provided with conventional cast frameworks during the first year of function. Material and Methods: A consecutive group of 65 patients with 67 prostheses were provided with CNC‐milled titanium frameworks in 23 upper and 44 lower jaws. During the same period, 61 consecutive patients were treated on a routine basis with 31 upper and 31 lower conventional gold alloy casting prostheses. Clinical and radiographic 1‐year data were collected for both the test and control groups. Results: A total of 14 of 729 inserted implants were lost during the follow‐up period (1.9%). All prostheses were functioning after 1 year except a conventional prosthesis with a cast framework, which was replaced by an implant‐supported over‐denture due to implant loss. The 1‐year cumulative survival rate (CSR) was 100% and 97.8% for CNC prostheses and implants, respectively. The corresponding CSR for the control group was 98.3% and 98.3%, respectively. Few problems were reported in both groups, and the clinical and the radiologic performances were similar for both groups. No mechanical complications except some resin veneer fractures (n = 6) were observed. The mean marginal bone loss for the test group during the first year in function was 0.4 mm (SD = 0.35) and 0.4 mm (SD = 0.33) in the upper and lower jaws, respectively. A similar pattern of bone reaction was also observed in the control group. Conclusion: CNC‐milled titanium frameworks can be used as an alternative to conventional castings in the edentulous jaw, presenting similar clinical and radiologic performances as conventional cast frameworks during the first year of function.     

Clinical experiences of implant-supported prostheses with laser-welded titanium frameworks in the partially edentulous jaw: a 5-year follow-up study

Background: Titanium frameworks have been used in the endentulous implant patient for the last 10 years. However, knowledge of titanium frameworks for the partially dentate patient is limited. Purpose: To report the 5-year clinical performance of implant-supported prostheses with laser-welded titanium frameworks in the partially edentulous jaw. Materials and Methods: A consecutive group of 383 partially edentulous patients were, on a routine basis, provided with fixed partial prostheses supported by Brånemark implants in the mandible or maxilla. Besides conventional frameworks in cast gold alloy, 58 patients were provided with titanium frameworks with three different veneering techniques, and clinical and radiographic 5-year data were collected for this group. Results: The overall cumulative survival rate was 95.6% for titanium-framework prostheses and 93.6% for implants. Average bone loss during the follow-up period was 0.4 mm. The most common complications were minor veneering fractures. Loose and fractured implant screw components were fewer than 2%. An observation was that patients on medications for cardiovascular problems may lose more implants than others (p <.05). Conclusions: The clinical performance of prostheses with implant-supported laser-welded titanium frameworks was similar to that reported for conventional cast frames in partially edentulous jaws. Low-fusing porcelain veneers also showed clinical performance comparable to that reported for conventional porcelain-fused-to-metal techniques.     

Rehabilitation of edentulous mandibles by means of five TiUnite implants after one-stage surgery: a 1-year retrospective study of 90 patients

Background: Recently, the present team reported the 1‐year data of one‐stage surgery and mainly early loading performed in edentulous mandibles using 750 turned Brånemark System® implants in 152 patients. Purpose: The aim of the present investigation was to retrospectively evaluate the 1‐year results of the same treatment technique, using Brånemark System implants with an oxidized surface (TiUnite?, Nobel Biocare AB, Göteborg, Sweden). The outcome was compared with that of the former study (control) on turned implants. Materials and Methods: The present study involved 90 individuals with 450 TiUnite implants of mainly the Brånemark System Mark III design, placed in edentulous mandibles and using one‐stage surgery. The prosthetic procedure was commenced as a mean 8 days after the surgical intervention. Intraoral radiographs were obtained at prosthesis insertion and at the 1‐year annual checkup. Failure rates of test and control groups were compared by means of the chi‐square test. Results: No implants were found to be mobile up to and including the first annual checkup, resulting in an implant cumulative survival rate (CSR) of 100%. The corresponding CSR for the control group was 97.5%, and this difference in implant survival was statistically significant when analyzed with the chi‐square test (p < .001). A statistically significant difference was also demonstrated (p < .01) when conducting the same statistical analysis on the patient level. The mean marginal bone resorption during the first year of function was 0.49 mm (SD 0.56), and the corresponding figures for the control study were 0.39 mm (SD 0.46). The central TiUnite implant, that is, the one placed in or in close relation to the symphyseal region showed significantly more bone loss (p < .05) than the corresponding central turned implant of the control study. Distally positioned test implants demonstrated less marginal bone loss than the corresponding central one. Conclusions: The outcome of 450 TiUnite implants placed in 90 patients with edentulous mandibles, of which 380 implants in 76 patients were followed for 1 year, showed an implant CSR of 100%. The figure was significantly different from the control study result of 97.5% on turned surface implants. The levels of marginal bone were close to identical for test and control implants at the 1‐year checkup.     

Implant-supported welded titanium frameworks in the edentulous maxilla: a 5-year prospective multicenter study

PURPOSE: This study evaluated the 5-year clinical and radiographic performance of fixed implant-supported maxillary prostheses with either welded titanium or conventional cast-gold alloy frameworks. MATERIALS AND METHODS: Fifty-eight consecutive patients were provided with 349 osseointegrated Br?nemark system implants in the edentulous maxilla at six different implant centers. Twenty-eight of the patients received, at random, prostheses with laser-welded titanium frameworks, and the remaining 30 patients had prostheses with conventional cast-gold alloy frameworks. Clinical and radiographic data were collected for 5 years after prosthesis placement. RESULTS: The titanium and cast-gold framework groups exhibited similar cumulative survival and success rates (CSR). The 5-year implant CSR from time of placement was 91.4% and 94.0%, respectively, and from prosthesis delivery the rate was 94.9% and 95.6%, respectively. The corresponding 5-year prosthesis CSRs were 96.4% and 93.3%. One patient from each group lost all the implants and turned to complete dentures within the first year of function. Another patient with a cast-gold framework had the prosthesis replaced after 4 years, basically because of problems with the veneering material. No fractures of implant components were observed during the follow-up period. Bone loss was on average 0.59 mm (SD 0.97 mm) during 5 years, with no statistical difference between the two groups. CONCLUSION: Welded titanium frameworks presented a similar favorable clinical performance as conventional cast-gold alloy frameworks in fixed implant-supported prostheses in the edentulous maxilla after 5 years in function. Implant failures were concentrated in only a few patients in each study group.     

Clinical experience of CNC-milled titanium frameworks supported by implants in the edentulous jaw: a 3-year interim report

Background: The use of computer numeric controlled (CNC)‐milled titanium frameworks is a new technique for framework fabrication, and few clinical reports have been made on this treatment modality. Purpose: The goal of this study was to report the clinical performance of implant‐supported prostheses with CNC‐milled titanium frameworks in the edentulous jaw and to compare the results with prostheses provided with conventional cast frameworks during the first 3 years of function. Materials and Methods: A consecutive group of 126 edentulous patients were provided by random distribution with 67 prostheses with CNC‐milled titanium frameworks in 23 upper and 44 lower jaws and 62 conventional prostheses with gold‐alloy castings in 31 upper and 31 lower jaws. Radiographic 1‐year data and clinical 3‐year data were collected for both the titanium and control group. Results: One prosthesis was lost in each group owing to loss of implants, and the overall 3‐year prosthesis cumulative survival rate was 98.2% for both groups. Patients with smoking habits experienced significantly more implant failures than nonsmokers (p =.006). Few problems were observed. No metal fractures were seen in the test group, whereas two frameworks and one abutment screw fractured in the control group. Resin veneer fractures were the most common complication, with a slightly higher incidence observed in the control group. Conclusions: Computer numeric controlled‐milled titanium frameworks can be used as an alternative to conventional castings in the edentulous jaw, presenting clinical performance similar to that of conventional cast frameworks during the first 3 years of function.     

Prospective study with a 2‐year follow‐up on immediate implant loading in the edentulous mandible with a definitive restoration using intra‐oral welding

Objectives: The aim of this prospective study was to evaluate the concept of intra‐oral welding as a suitable technique for the fabrication of a restoration for edentulous mandibles on the same day as surgery using tapered connection implants. Material and methods: Each of 20 patients had an edentulous mandible and received four inter‐foraminal, tapered connection implants. All implants were immediately loaded with a fixed restoration supported by an intra‐orally welded titanium framework. Final abutments were connected to the implants and then a titanium bar was welded to them using an intra‐oral welding unit. This framework was used as a support for the final restoration, which was fitted on the same day as implant placement. Mean marginal bone loss and radiographically detectable alteration of the welded framework were assessed using periapical radiographs immediately after surgery, and at 6‐, 12‐ and 24‐month follow‐up examinations. Results: Seven males and 13 females, with an average age of 56.5 years (SD=15.1; n=20), were consecutively treated with 80 immediately loaded implants. No fracture or radiographically detectable alteration of the welded frameworks was evident. All implants osseointegrated and a 100% implant survival rate was achieved at the 24‐month follow‐up. The accumulated mean marginal bone growth was 0.21 mm (SD 0.25, n=80). The average pocket probing depth was 1.38 mm (SD 0.41). Conclusions: The intra‐oral welding technique applied to the delivery of a final restoration of the edentulous mandible over immediately restored tapered connection implants seems to have no adverse effect on marginal bone loss and implant survival. To cite this article:
Degidi M, Nardi D, Piattelli A. Prospective study with a 2‐year follow‐up on immediate implant loading in the edentulous mandible with a definitive restoration using intra‐oral welding.
Clin. Oral Impl. Res. 21 , 2010; 379–385.
doi: 10.1111/j.1600‐0501.2009.01865.x     

On the role of number of fixtures, surgical technique and timing of loading

AIMS: The aims of this thesis were to analyze reduced number of implants supporting full arch fixed mandibular prostheses and fixed partial dentures (FPDs), non-submerged healing and early loading in the edentulous mandible. A further aim was to evaluate fit of Computer Numerical Controlled (CNC) milled I-Bridge frameworks. MATERIAL & METHODS: Paper I. One hundred and nineteen patients rehabilitated with full arch mandibular prostheses supported by four implants were evaluated after a mean follow-up of 4.4 years. Paper II. A total of 178 patients provided with FPDs supported by two (n=92) or three implants (n=122) of whom 123 were evaluated after a mean follow-up of 9.4 years. Paper III. Early and delayed loading of full arch mandibular prostheses were evaluated in 109 patients, 54 with delayed loading and 55 with early loading, with a mean follow-up of 3.6 years. Paper IV. Submerged and non-submerged implant placement for supporting fixed prostheses in the edentulous mandible were evaluated after five years in 29 patients. Paper V. The precision of fit of CNC-milled I-Bridge frameworks was evaluated using two different implant systems. RESULTS: Paper I. The five-year cumulative survival rate (CSR) for implants was 99.1% and for prostheses 100%. Mean bone loss from baseline to five-year follow-up was 0.5 mm. No indication could be found that the number of supporting implants influenced the prosthetic complications. Paper II. The five-year implant and prosthesis CSR was 97.7% for two-implant supported FPDs and 97.3% for three-implant supported FPDs. Mean bone loss at five years was 0.4 mm. Significantly more prosthetic and abutment screw loosening were seen in two-implant supported FPDs. Paper III. Five-year CSR for implants was 94.4% and 92.5% for prostheses in early loading, and 97.9% and 98.0% in the delayed loading group. More prostheses needed adjustment or replacement in the early group, but patients treated with early loading were more pleased with the treatment procedure. Paper IV. Five-year CSR survival rate was 99.4%. Three implants fractured in one patient. Mean bone loss at five years was 0.7 mm in submerged implants and 0.5 mm in non-submerged implants. Paper V. All frameworks demonstrated clinically acceptable fit with mean distortion values within 23 microm (x-axis), 26 microm (y), 4 microm (z- axis) and 34 microm (3-D) for all frameworks. Control frameworks displayed greater levels of distortion than frameworks produced in a strict test situation. CONCLUSION: A reduction of the number of supporting implants to four implants in full arch mandibular prostheses and two implants in three unit FPDs in partial edentulous jaws resulted in the same clinical outcome as when more implants are used. Non-submerged implant placement in the edentulous mandible was as predictable as submerged, but early loading of implant-supported mandibular prostheses incurred more prosthetic complications. Computer numerical controlled milled frameworks presented levels of precision of fit within limits considered to be clinically acceptable and superior to earlier published results on cast frameworks.     

Implant treatment in the edentulous maxillae: a 15-year follow-up study on 76 consecutive patients provided with fixed prostheses

Background: Few long‐term follow‐up studies are available on implant treatment based on patient level data related to time. Purpose The aim of this study was to report 15‐year patient‐based data in relation to time of follow up after treatment with fixed prostheses supported by implants in the edentulous upper jaw. Materials and Methods Seventy‐six edentulous consecutive patients, provided with 450 turned Brånemark implants, were followed up with regard to maintenance, complications, and radiographs taken during the follow‐up period. Results Forty‐four patients provided with 247 implants were lost to follow up. Patients followed up for 15 years showed as a group a trend of better implant survival than patients lost to follow up (p > .05). Altogether, 37 implants and 5 fixed prostheses failed during the follow‐up period. Most implants were lost at abutment surgery (n? 15) and another nine during the first year of function. The 15‐year implant and fixed prosthesis cumulative survival rate was 90.9 and 90.6%, respectively. Resin veneer fractures caused most problems, more frequent in the earlier stage while severe wear increased in the later stage of follow up. No implant fractures or loosening of abutment/bridge locking screws were noted. The mean marginal bone loss was 0.5 mm (SD 0.47) after 5 years, followed by only minimal average changes during the following years. No radiographic parameter showed any time‐dependent relationship. The percentage of patients presenting at least one implant with more than 2.0‐mm bone loss was 4.9% in the interval from 0 to 5 years and 4.0% between 10 and 15 years. Only 1.3% of implants showed >3.0 mm accumulated bone loss after 15 years. Conclusion Implant treatment in the edentulous upper jaw functions well in a 15‐year time perspective, but an insignificant trend of higher implant failures was observed for patients lost to follow up. Besides wear and fractures of veneers, no other parameter showed any time‐related relationship, indicating an increased risk for more complications during later stages of follow up. However, accumulation of smaller amount of bone loss during the years resulted in an increasing number of implants and patients with bone levels below the third thread, which could be speculated to increase future maintenance after 15 years.     

Evaluation of Clinical Outcomes and Bone Loss around Titanium Implants with Oxidized Surface: Six‐Year Follow‐Up Results from a Prospective Case Series Study

Purpose: The aim of this prospective study was to assess long‐term clinical outcomes and peri‐implant bone level changes around oxidized implants supporting partial fixed rehabilitations. Materials and Methods: Twenty‐two partially edentulous patients were included in the study. A total of 33 fixed rehabilitations were placed, supported by 54 titanium implants with oxidized microtextured surface. Prostheses were delivered after 3 and 6 months of implant placement in the mandible and maxilla, respectively. Patients were scheduled for follow‐up at 6 and 12 months and then yearly. At each follow‐up, plaque level and bleeding scores were assessed and periapical radiographs were taken. The main outcomes were prosthesis success, implant survival, implant success, and marginal bone level change. Results: Three patients were excluded from the study because they did not attend the 1‐year follow‐up. Nineteen patients, accounting for 49 implants, were followed for at least 6 years after prosthesis delivery. The mean follow‐up duration was 81.8 months (range 75–96 months). One mandibular single‐tooth implant failed after 1 year in a smoker woman. Cumulative implant survival and success at 6 years were 98.0% and 95.9%, respectively. Prosthesis success was 96.7%. The mean peri‐implant bone loss at 6 years was 0.76 ± 0.47 mm. Not significantly (p = .75) greater bone loss was found in the maxilla (0.78 ± 0.14 mm, n = 19) as compared with the mandible (0.74 ± 0.59 mm, n = 30). In the maxilla, bone loss was significantly greater around implants supporting partial prostheses as compared with single‐tooth implants (p = .03). Full patient satisfaction was reported. Conclusion: Implants with oxidized microtextured surface may achieve excellent long‐term clinical outcomes in the rehabilitation of partial edentulism.     

Impact of Platform Switching on Peri‐Implant Bone Remodeling around Short Implants in the Posterior Region, 1‐Year Results from a Split‐Mouth Clinical Trial

Aim: To assess the effect of platform switching on peri‐implant bone remodeling around short implants (8.5 mm) placed in the resorbed posterior mandibular and maxillary region of partially edentulous patients. Materials and Methods: Seventeen patients with one or more missing teeth at both sides in the posterior region were, according to a split‐mouth design, randomly assigned to be treated with a platform‐matched (control) implant on the one side and a platform‐switched implant (test) on the other side. A total of 62 short implants (8.5 mm) with a dual‐acid etched surface with nanometer‐sized calcium phosphate particles was placed. Follow‐up visits were conducted one month and one year after placing the implant crown. Outcome measures were interproximal bone level changes, implant survival and clinical parameters. Results: One year after loading, peri‐implant bone remodeling around test implants (0.53 ± 0.54 mm) was significant less than around control implants (0.85 ± 0.65 mm; p = .003). With regard to implant survival and clinical parameters no significant differences were observed between test and control implants. Conclusions: This study suggested that peri‐implant bone remodeling is affected by platform switching. One year after loading, interproximal bone levels were better maintained at implants restored according to the platform switching concept.     

Long-term follow-up of severely atrophic edentulous mandibles reconstructed with short Brånemark implants

Background: Oral implant treatment (Brånemark System) of edentulous mandibles has been presented in numerous studies. However, with regard to the severely atrophic lower jaw, no long‐term follow‐up studies with solely short implants are available. Purpose: The purpose of the present investigation was to retrospectively follow the long‐term treatment outcome of patients with severely resorbed edentulous mandibles being subjected to oral implant placement with short (6–7 mm) Brånemark implants. Materials and Methods: A total of 247 standard (7 mm long, 3.75 mm) and 13 wide (6 mm long, 5 mm) implants were inserted in 49 patients, all of whom exhibited severe resorption of edentate mandibles. Fixed implant‐supported prostheses were manufactured for 45 patients, whereas 4 patients received overdentures. The patients were followed for a mean period of 8 years (range, 1–14 yr). Results: Seventeen implants failed during the study period (cumulative implant survival rate 95.5% at 5‐yr and 92.3% at 10‐yr follow‐up). Implant‐supported constructions were worn continuously throughout the investigation by all study subjects. Marginal bone loss, measured after 1, 5, and 10 years of function, concurred with studies of Brånemark implants placed in more voluminous mandibles. No major clinical or construction complications occurred in the followed patients. Conclusions: The outcome of the present study showed that placement of short Brånemark implants without the use of bone grafting procedures for reconstruction of severely atrophic edentulous mandibles is a highly predictable treatment procedure.     

Cemented CeraOne and porcelain fused to TiAdapt abutment single-implant crown restorations: a 10-year comparative follow-up study

Background: Long‐term data comparing cemented and noncemented single‐implant restorations has not been reported. Aim: To compare clinical and radiographic performance of single‐implant crown restorations made by either directly baked porcelain to custom‐made TiAdapt? titanium abutments (Nobel Biocare AB, Göteborg, Sweden) (test) or cement crowns onto CeraOne® (Nobel Biocare AB) abutments (control) after 10 years in function. Materials and Methods: Altogether, 35 consecutive patients were provided with 41 turned single Brånemark System® implants (Nobel Biocare AB) in the partially edentulous upper jaw. By random, 15 and 20 patients were provided with 18 test and 23 control implant crowns, respectively. Thereafter, clinical and radiographic data were collected and compared between the two groups. Results: None of the implants were found loose during the follow‐up period (100%). Few clinical problems were observed, and the overall average marginal bone loss was 0.26 mm (SD 0.64) during 10 years in function. After the final tightening of the crowns, no significant differences were observed between the test and control groups (p > .05). The head of the implants was placed on an average 6.3 mm (SD 2.24) below the cement/enamel junction of the adjacent teeth (range 2.5–10.0 mm). Implants with reported mechanical and/or mucosal problems or placed more apically in relation to the adjacent teeth did not present more bone loss as compared with implants with no problems or placed more coronally, respectively (p > .05). Conclusions: There seems to be no obvious clinical or radiographic differences between the test and control single‐implant restorations during 10 years of follow‐up. Occasionally, some restorations presented loose abutment screws and/or fistulas during follow‐up. This implies a certain need for maintenance where a one‐piece single‐implant protocol (test) allows both for a simple clinical procedure at placement without cementation problems, as well as for an easy and simple maintenance of installed single implant crowns in long‐term function.     

Early complete failures of fixed implant-supported prostheses in the edentulous maxilla: a 3-year analysis of 17 consecutive cluster failure patients

Background Clusters of implant failures in the edentulous maxilla seem to occur in some patients. To create groups for analysis with higher numbers of these patients implies large original groups for inclusion. Purpose The aim of this study was to retrospectively describe and compare a group of “cluster failure patients” with randomly selected patients treated in the edentulous maxilla. Materials and Methods From a group of 1,267 consecutively treated patients in one clinic, all patients presenting failing fixed implant‐supported prostheses within the first 3 years of follow‐up were included. All patients were treated with turned titanium implants using two‐stage surgery. A control group of equal number of patients were created for comparison. Data on patients were retrospectively retrieved from their records, and compared. Results Seventeen patients (1.3%) met the inclusion criteria in the entire group. The bone resorption index revealed less bone quantity in the study group (p < .05) during implant placement, but there was no difference regarding primary implant stability at first‐stage surgery. The distribution of short and long implants showed relatively higher number of short implants in the study group (p < .05), and more patients had a presurgical discussion on the risk of implant failure prior to treatment in this group (p < .05). Only 5 out of 102 implants (4.9%) were lost before prosthesis placement as compared to 38 and 25 lost implants during the following two years in the study group. Smoking habits and signs of bone loss related to periodontitis in the lower dentition were more frequent in the study group, but did not reach a significant level (p > .05). Conclusion The results indicate that bone quantity, reflected in fixture length, has a significant impact on increased implant failure risk. Other factors of interest as predictors for implant failures could be smoking habits and also possibly signs of periodontitis in the opposing dentition.     

Splinted and Unsplinted Short Implants in Mandibles: A Retrospective Evaluation With 5 to 16 Years of Follow‐Up

Background: The aim of this retrospective study is to investigate the medium‐ to long‐term prognosis of short implants in partially and totally edentulous patients with mandibular bone atrophy. Methods: The study involved 109 patients with 280 implants placed in the mandible. The implants were 7 or 8.5 mm long and 3.75 or 4 mm in diameter. The implant surfaces were machined (M; n = 176) or rough (R; n = 104). Patients were asked to attend a radiographic and clinical follow‐up, and their previous clinical records and radiographs were assessed. Implant‐related and prosthetic failures and complications were recorded. Results: The mean follow‐up was 9 years (range of 5 to 16 years). The survival rate (SSR) and success rate (SR) were calculated using life‐table analysis for both M and R short implants. The M implants had a 16‐year SSR of 95.7% and a corresponding SR of 93.9%, whereas the 16‐year SSR and SR for the R implants were 97.2% and 95.2%, respectively. The mean ± SD bone resorption for all implants was 1.37 ± 0.5 mm. For marginal bone loss, there was no statistically significant difference between the two implant lengths (P = 0.38) or diameters (P = 0.34) or between the M and R implant surfaces (P = 0.47). Conclusions: Different implant lengths, diameters, and surface treatments do not appear to influence the prognosis of the implant. Within the limitation that most of the short implants were splinted to longer implants, the reduced length of the fixtures did not worsen the long‐term survival of the implant‐supported fixed prostheses.     

Turned Brånemark System implants in wide and narrow edentulous maxillae: a retrospective clinical study

Background: The available jawbone volume is regarded as one of the most important factors when assessing the prognosis of oral implants in the rehabilitation of the edentulous maxilla. Purpose: The aim of the current investigation was to retrospectively evaluate and compare the outcome of implants placed in edentulous maxillae with either wide or narrow jaw shapes. The marginal bone loss and implant cumulative survival rates (CSRs) were calculated and analyzed with special reference to smoking habits. Materials and Methods: The study included 75 individuals with edentulous maxillae, of which 33 patients exhibited wide (group A) and 42 patients exhibited narrow jaw shapes (group B). A total of 506 turned Brånemark System® (Nobel Biocare AB, Göteborg, Sweden) implants were inserted (226 in group A and 279 in group B) and followed clinically up to 7 years. Smoking habits were recorded. Radiographs were obtained at connection of prostheses, and at the 1‐ and 5‐year follow‐up visit. The marginal bone loss was calculated for the groups and analyzed using t‐test. Results: Twenty‐eight implants were lost during the study period, revealing implant CSRs at 7 years of 94.6% (11/226) and 93.6% (17/279) for wide and narrow crests, respectively. No difference in marginal bone loss was seen between the two groups, although a trend toward more bone loss was recorded for patients with wide crests. Smoking habits were more common in group A (45%) than in group B (31%). During the first year of function, smokers lost significantly more marginal bone than nonsmokers (p = .0447), albeit this difference did not prevail (p > .05) at the end of the study period. Conclusions: The implant CSRs at 7 years were equally good for the two groups of patients with various jaw shapes. Initially, smokers showed significantly more marginal bone loss than nonsmokers.     

Evaluation of 316 narrow diameter implants followed for 5–10 years: a clinical and radiographic retrospective study

Objectives: Narrow diameter implants (NDIs; diameter >3.75 mm) are useful in replacement of missing incisor teeth and when the bucco‐lingual width of the edentulous crest is insufficient. The present study evaluated the success and survival rates, peri‐implant parameters, mechanical and prosthetic post‐loading complications of NDIs followed over a 10‐year period. Material and methods: Three hundred and sixteen NDIs were inserted into 139 patients and restored with 120 prostheses. Clinical and radiographic assessment data were collected during recall visits. Implant success (SC), cumulative survival rate (CSR), marginal bone loss (MBL), peri‐implant conditions and prosthetic complications were assessed. Cox proportional hazards regression analysis, Kaplan–Meier survival curves with the log‐rank test and life table analysis were used to evaluate the outcome of NDIs within comparable subgroups. MBL and peri‐implant parameters measured annually were further analyzed. Results: The mean follow‐up time was 9.1 years (range: 60–124 months). Twelve implants were lost in the healing phase and two during function. The mean MBL in the maxilla and the mandible was 1.32 ± 0.13 and 1.28 ± 0.3 mm, respectively, after 10 years. SC and CSR were 91.4% and 92.3%, respectively, after 124 months. Smoking and posterior localization were associated with an increased risk of failure. Cement loosening (16.8%) was the most common prosthetic complication. No implants were fractured. Conclusions: NDIs can be used with confidence where a regular diameter implant is not suitable. MBL around NDIs occurred predominantly within 2 years of loading and was minimal thereafter. Further studies are required to clarify the possible risks associated with smoking and posterior placement. To cite this article:
Arιsan V, Bolukbasι N, Ersanlι S, Ozdemir T. Evaluation of 316 narrow diameter implants followed for 5–10 years: a clinical and radiographic retrospective study.
Clin. Oral Impl. Res. 21 , 2010; 296–307.
doi: 10.1111/j.1600‐0501.2009.01840.x