A 3 to 4 year study of single tooth hydroxylapatite coated endosseous dental implants.

OBJECTIVE: To evaluate the clinical effectiveness, common complications and maintenance associated with hydroxylapatite (HA) coated cylindrical implants when used to support single crowns. DESIGN: A prospective medium term clinical study of the Calcitek HA-coated implant. SETTING: Implant placement, crown fabrication and follow-up procedures were carried out at the Leeds Dental Institute, between 1990 and 1998. SUBJECTS AND METHOD: 26 patients (33 implants) participated in the trial. They were referred from general dental practitioners because of their suitability for single tooth implant placement. MAIN OUTCOME MEASURES: The implants were assessed using recognised clinical review procedures e.g. radiographs and soft tissue assessments. RESULTS: At exposure there was 100% implant integration. The cumulative survival rate over 4 years was 100%. In five implants there was cervical bone loss of more than 4 mm and these were classified as failing. This gave an overall cumulative success rate of 58% by year 4. CONCLUSION: The Calcitek HA-coated single tooth implant shows exceptionally high initial integration however, the longer term results suggest that the cervical bone level adjacent to the implant failed to establish a steady state. Doubts remain regarding the long-term prognosis of these cylindrical HA-coated implants.     

A 1- to 12-year clinical evaluation of 106 endosseous implants supporting fixed and removable prostheses

The purpose of this article is to report on the long-term clinical evaluation of patients treated with dental implants. A total of 106 implants were placed in 34 patients and restored with fixed partial dentures and overdentures. The 12-year cumulative implant survival and success rates were 95.2% and 90.2%, respectively. Probing depths around mandibular implants were significantly lower than those around maxillary implants (P < .05). The cumulative implant success rate in nonsmokers was 97.7%, but this dropped to 75.81% in smokers. Also, patients rehabilitated with implant-supported overdentures had more peri-implant tissue inflammation than patients with fixed prostheses.     

Implant-supported maxillary overdentures retained with milled bars: maxillary anterior versus maxillary posterior concept--a retrospective study

PURPOSE: The aim of the present retrospective investigation was to evaluate implant-supported maxillary overdentures using either anterior (group 1) or posterior (group 2) maxillary implant placement. MATERIAL AND METHODS: Maxillary overdentures were planned with support by either 4 implants placed in the maxillary anterior region (group 1) or 6 to 8 implants placed in augmented maxillary posterior regions (group 2, bilateral sinus augmentation) and anchored either on an anterior or on 2 bilaterally placed milled bars. Cumulative implant survival rate, peri-implant conditions (marginal bone loss, pocket depth, Plaque Index, Gingival Index, Bleeding Index, and Calculus Index) and the incidence and type of prosthodontic maintenance were assessed and compared for the 2 groups. In addition, the cumulative survival rate for implants placed in grafted regions was compared with that of implants placed in nongrafted regions. RESULTS: Thirty-four patients (16 for group 1 and 18 for group 2) with 179 implants were available for follow-up examination after a mean period of 42.1 +/- 20.1 months. Four initially placed implants failed to osseointegrate and were replaced, but no further losses were seen during the loading period, for a 5-year cumulative implant survival rate of 978%. No differences in implant survival rates were seen between either the group-1 (98.4%) and group-2 (97.4%) concepts or nongrafted (98.0%) and grafted (97.5%) implants. The peri-implant parameters showed a healthy soft tissue, good oral hygiene, and an acceptable degree of peri-implant marginal bone loss. The rigid fixation of all overdentures was associated with a low incidence of prosthodontic maintenance, without any significant differences between the 2 groups. CONCLUSIONS: In well-planned overdenture treatment programs, a high survival rate and excellent peri-implant conditions can be achieved for implants placed in the anterior or posterior maxilla. Rigid anchorage of maxillary overdentures either on an extended anterior milled bar or on 2 bilateral posterior milled bars provides for a low incidence of prosthodontic maintenance.     

A long-term study of implants supporting overdentures as a model for implant success

BACKGROUND: Implant-supported overdentures have been a common treatment for edentulous patients for the past 20 years, achieving good clinical results. The purpose of this study was to examine survival and success rates of implants supporting overdentures in the maxilla and mandible and to examine the influence of factors related to patients, implant procedure, implant data, and follow-up period on implant success. METHODS: During a 10-year period (1990 to 2000), 285 implants were placed in 62 patients to support 69 overdentures (seven patients had overdentures in both jaws). Patients ranged in age from 45 to 85 years (mean 64.5 years). The files of 61 patients, including 277 implants supporting 68 overdentures (14 maxillary and 54 mandibular), had measurable radiographic post-exposure follow-up (range 6.63 to 110.93 months, mean 37.93 months) for cervical bone loss (CBL) measurements. Bone loss was measured by radiographic examination in which the mean number of exposed threads in mesial and distal sides of the implant was considered. Implants were rehabilitated by overdentures with bar (N = 52) or ball (N = 16) attachments. RESULTS: Implant survival rate was 96.1% (11/285 did not survive) and total 10-year cumulative survival rate was 95.4% (maxilla, 83.5%, mandible, 99.5%). The success rate was 70.4% (maxilla, 41.9%; mandible, 80.8%) when using Albrektsson et al. success criteria. A logistic regression analysis showed that the maxilla (P <0.0001) and a short follow-up period (up to 5 years) (P = 0.017) were the most influencing factors enhancing CBL. CONCLUSIONS: 1) Survival of implants supporting overdentures was very high; 2) implants supporting overdentures in the maxilla had greater CBL than in the mandible; and 3) new criteria of implant success should be considered.     

A long-term follow-up study of non-submerged ITI implants in the treatment of totally edentulous jaws. Part I: Ten-year life table analysis of a prospective multicenter study with 1286 implants

In this prospective multicenter study, non-submerged ITI implants were followed in order to evaluate their long-term prognosis in fully edentulous jaws. A total of 1286 implants were inserted in 233 consecutive patients and, after a healing period of three to six months, the successfully integrated implants were restored with 163 overdentures and 95 fixed full-arch bridges. This prospective study not only calculated the 10-year cumulative survival and success rates for the 1286 implants by life table analysis, but also evaluated the actual survival and success rates for 498 implants after at least five years of functional loading. In addition, cumulative success rates were calculated for implant subgroups according to implant length and location. Additional analyses were performed to evaluate the estimated and actual survival and success rates of the implants in relation to various prosthetic rehabilitation techniques. The 10-year cumulative survival and success rates were 95.9% and 92.7%, respectively. The actual 5-year survival and success rates of the first 498 implants that were inserted were 97.7% and 95.0%, respectively. The analysis of implant subgroups showed slightly more favourable cumulative success rates for 12 mm long implants (93%), in comparison to 10 mm and 8 mm long implants (91.6% and 89.6%, respectively). The cumulative success rate for mandibular implants (approximately 94%) was also more favourable than that for maxillary implants (approximately 91%). Patients who were loaded with both maxillary and mandibular prostheses maintained success rates well above 90%; while only implants that were inserted to support maxillary overdentures that were retained by Dolder bars showed a success rate below 90%.     

A 48-month multicentric clinical investigation: implant design and survival

This report is based on a total of 2,955 implants of 6 different designs, randomized and placed in 829 patients and followed for 48 months. Implant failure was defined as nonintegration at uncovering or removal due to mobility, persistent pain, infection, and evidence of radiographic bone loss. Failures were reported for 3 phases of treatment: implant placement to uncovering (phase 1), uncovering to loading (phase 2), and postloading (phase 3). Differences in survival were compared with Kaplan-Meier survival curves. The maxillary single tooth application resulted in 95.2% survival for the hydroxyapatite-coated grooved implants. In the maxillary completely edentulous application, survival of hydroxyapatite grooved and screw implants were considerably better compared with the titanium screw implants. The hydroxyapatite-coated cylinder had better survival than the titanium basket and screw designs in the mandibular completely edentulous application. The hydroxyapatite-coated cylinder and grooved implants in the maxillary posterior partially edentulous application had similar survival rates. The survival of the hydroxyapatite-coated cylinder exceeded that of the titanium basket in mandibular posterior partially edentulous applications. Analyses by phase of treatment indicated a pattern of early failure for nonhydroxyapatite-coated implants compared with hydroxyapatite-coated implants. The implant with the highest survival at all phases of treatment was the hydroxyapatite-coated press-fit cylinder. Two hydroxyapatite-coated implant designs performed well in the challenging posterior maxillary region.     

Clinical outcome of dental implants placed in fibula-free flaps used for the reconstruction of maxillo-mandibular defects following ablation for tumors or osteoradionecrosis

OBJECTIVES: (a) To evaluate the clinical outcome of fibula revascularized flaps used for the reconstruction of maxillary and mandibular defects due to resection for tumors or osteoradionecrosis and (b) to evaluate the survival and success rates of implants placed in the reconstructed areas. MATERIAL AND METHODS: In a 8-year period (1995-2002), 59 patients, 38 males and 21 females, aged from 13 years to 69 years (mean age: 48.7 years), presenting with maxillary and mandibular defects due to resection for tumors or osteoradionecrosis, were reconstructed with fibula-free flaps. Of the 59 patients, 16 received 71 implants for the prosthetic rehabilitation of the reconstructed edentulous areas. RESULTS: Out of 59 fibula-free flaps, three failed and had to be removed, nine underwent partial necrosis involving the bone segment and/or the skin paddle but survived, while the remaining 47 healed uneventfully. The mean follow-up of patients after the reconstruction was 55 months (range: 24-120 months). The cumulative survival rate of fibula-free flaps was 94.9%. The mean follow-up of the 16 patients treated with dental implants and implant-supported prostheses was 50.2 months (range: 24-96 months). The cumulative implant success and survival rates of implants were 98.6% and 93.1% respectively. CONCLUSION: The reconstruction of maxillo-mandibular defects following ablation for tumors or osteoradionecrosis with fibula-free flaps has been demonstrated to be a reliable technique with good long-term results. Implants placed in the reconstructed areas were demonstrated to integrate normally, with success and survival rates comparable to those obtained in case of implants placed in native bone.     

Morse taper connection implants supporting "planned" maxillary and mandibular bar-retained overdentures: a 5-year prospective multicenter study

Objectives: In contrast to the excellent long‐term outcomes described for implant‐supported mandibular overdentures, less favorable long‐term survival and success rates have been reported for maxillary implants supporting overdentures. The aim of this study was to evaluate the treatment outcome of “planned” bar‐retained maxillary and mandibular overdentures supported by Morse taper connection implants, investigating implant survival, peri‐implant tissue health, marginal bone resorption and prosthetic complications. Material and methods: Over a 2‐year period, 60 patients were enrolled in this study, in four different clinical centers. The overdentures (maxilla 38, mandible 34) were planned with support from four implants anchored on a bar. A total of 288 Morse taper connection implants (Leone Implant System^®) were inserted (152 maxilla, 136 mandible). Implants were evaluated 5 years after insertion. Success criteria included the absence of pain, suppuration or clinical mobility, the distance between implant shoulder and first crestal bone–implant contact (DIB) <2 mm and no exudate history. Results: The overall 5‐year implant survival rate was 98% (maxilla 97.4%, mandible 98.6%), with 282 implants still in function. Among these surviving implants, 278 (98.6%) were classified in the success group. At the 5‐year examination, the mean DIB was 0.7 mm (±0.53). Few prosthetic complications were reported. Conclusions: With “planned” bar‐retained maxillary and mandibular overdentures supported by Morse taper connection implants, satisfactory survival and success rate can be achieved. To cite this article:
Mangano C, Mangano F, Shibli JA, Ricci M, Sammons R, Figliuzzi M. Morse taper connection implants supporting “planned” maxillary and mandibular bar‐retained overdentures: a 5‐year prospective multicenter study.
Clin. Oral Impl. Res. 22 , 2011; 1117–1124
doi: 10.1111/j.1600‐0501.2010.02079.x     

A radiographic review of bone levels around Calcitek dental implants supporting mandibular over-dentures. Preliminary results at 3 to 6 years

This retrospective study aimed to measure marginal bone resorption around cylindrical hydroxyapatite-coated implants retaining mandibular overdentures and compares this between two- and four- implant supported overdentures. Twenty three edentulous patients received 66 implants in their anterior mandible and were restored with overdentures. Panoramic radiographs one week post-operatively and at last recall were compared and marginal bone loss calculated. The mean recall interval was 51.22 months. The mean cumulative bone loss was 1.08 mm and the mean annual bone loss 0.263 mm. There was no significant difference between two- and four- implant overdentures. The results were comparable with other reports.     

Prospective clinical evaluation of 835 multithreaded tapered screw-vent implants: results after two years of functional loading

Multithreaded tapered screw implants have been used for several years, but lack of clinical documentation about marginal bone stability and survival rates have raised concerns about the design among some clinicians. This study prospectively evaluated the survival rates, success rates, and marginal bone stability of multithreaded tapered screw implants. A total of 835 implants in diameters of 3.7 mm (9%), 4.7 mm (76%), and 6.0 mm (15%) were placed in 328 patients using a single-stage, delayed-loading protocol. The implants were restored with a variety of prostheses and monitored over 2 years of functional loading. Five implants failed and were removed before loading. Cumulative implant survival was 99.4% (n = 835); differences between mandibular (99.0%, n = 408) and maxillary (99.8%, n = 427) implants were not statistically significant (P > .20). Mean marginal bone resorption was 1.66 mm (+/- 0.13 mm). Six implants failed to meet the success criteria by sustaining mesial and distal bone loss below the first implant thread; however, they remained stable and continued functioning without pain or inflammation. Cumulative implant success was 98.6% (n = 835); differences between maxillary (98.6%) and mandibular (98.8%) implants were not statistically significant (P > .20). Success rates by implant diameter were 98.6% (3.7 mm), 98.4% (4.7 mm), and 100% (6 mm). After 2 years of functional loading, survival and success rates for multithreaded tapered implants placed in a nonsubmerged protocol equaled or surpassed those of single-thread, straight-walled implant historical controls.     

Multicenter retrospective study of ITI implant-supported posterior partial prosthesis in Jordan

Purpose: The aim of this multicenter study was to evaluate success and restorative problems of ITI (ITI Dental Implant System®, Straumann AG, Basel, Switzerland) implant‐supported posterior partial prostheses in Jordan. Materials and Methods: One‐hundred forty‐one ITI implants were placed in the posterior region of the mandible or the maxilla in 66 patients at multiple clinical practices in Jordan. The age of the patients ranged from 17 to 85 years. The implants were retrospectively analyzed from the first date of placement in September 1999 until May 2006. Eighty‐three implants (58.87%) were placed in the mandible, and 58 (41.13%) in the maxilla. The implants were loaded with either cement‐retained single‐ or multiple‐tooth replacements. Results: Three maxillary implants of two male patients have been lost (2.13% of the total and 5.12% of the maxillary implants). Failed implants were of wide‐neck type with 6‐mm lengths. Moreover, in another two male patients, two single implants at the maxillary premolar region exhibited significant bone loss from the buccal side of the implant surface (2‐mm bone resorption). Those two implants are still functioning and were included in calculating the survival rate but not the success rate. Therefore, the cumulative survival rate for both arches and genders was 97.87% and that for male patients in the maxillary region was 94.88%. The cumulative success rate for both arches and genders was 96.45% and that for the maxillary region was 86.21%. The corresponding rates concerning implants in female patients and the posterior mandible of both genders were 100% for both survival and success rates. Only one crown (mandibular) and another two abutment bridge (maxillary) were decemented in different patients (2.13%). Conclusions: The survival and success rates of implants placed in male patients and in the maxilla were lower than that of implants placed in female patients and in the mandible. Cement‐retained restorations showed minimal complications.     

Long-term evaluation of 282 implants in maxillary and mandibular molar positions: a prospective study.

BACKGROUND: Placement of implants into molar positions presents diagnostic, surgical and prosthetic challenges. There are few reported studies for implants placed into molar positions. The purpose of this prospective longitudinal study is to report long-term clinical outcomes for 282 implants placed into molar positions. METHODS: Two-hundred-twelve patients received 282 implants. Implant size, location, jaw shape, and bone quality were recorded for all implants placed into molar positions. Seventy implants were inserted in maxillae and 212 in mandibles. Marginal bone level changes in maxillae and mandibles were measured from non-standardized periapical radiographs taken at abutment connection and an average follow-up of 3.9 years. Mesial-distal implant measurements were made from the top of the implant cylinder to the first point of bone to implant contact. In mandibles, 39 implants were used for single molar replacements, 67 implants were placed into excellent bone quality (type I) and 113 were in good bone quality (type 11); 145 implants were placed into bone with moderate bone resorption (type B); 166 implants were placed in first molar positions and 46 in second molar sites. RESULTS: At 6 years the cumulative success rate (CSR) for mandibular implants is 91.5%, and the success rate from the 2 to 3 year follow-up is 100%. Of the 70 implants placed in maxillae, 16 replaced single molars. Thirty-two implants were placed in jaw shape B with type 2-bone quality. For maxillary implants, the 6-year CSR was 82.9% and the success rate remained steady at 100% after the 2 to 3 year follow-up. For maxillary implants, at abutment connection the average marginal bone level was 1.67 mm, while at follow-up it was 1.98 mm. These differences were statistically significant (P = 0.04), but are not considered to be clinically significant. For mandibular implants, at abutment connection the mean marginal bone level as measured from radiographs was 2.11 mm, and at follow-up was 2.02 mm. This slight gain in bone level was not statistically significant and is not considered to be clinically significant. CONCLUSIONS: Results of this prospective longitudinal study of implants placed into molar positions indicates favorable clinical outcomes. These CSR rates (91.5% mandibles, 82.9% maxillae) are less than what has been reported for implants placed into mandibular and maxillary anterior segments. Differences in outcomes between anterior and posterior locations may be related to bone quality and quantity.     

Long-term treatment outcomes in edentulous patients with implant overdentures: the Toronto study

PURPOSE: Few long-term studies on overdentures report both implant and prosthodontic outcomes. The aim of this prospective study was to report long-term prosthodontic- and implant-related treatment outcomes of patients treated with design-specific implant-supported overdentures. MATERIALS AND METHODS: Between 1982 and 1992, 45 consecutively treated patients received a total of 47 overdentures (42 mandibular and 5 maxillary) supported by Br?nemark implants. Prospective clinical and radiographic data were collected over the observation period; this study presents the most recent treatment outcomes. RESULTS: Thirty patients (mean age 70 years) with 32 prostheses attended the final recall visit, with 67% of patients followed for 15.53 years (range 10 to 19 years). Six implants failed, and the prosthetic plan and implant cumulative survival rates were both in excess of 90%. Mean marginal bone loss around implants after the first year of loading was small (0.05 mm/year), although the individual variation was high. Linear regression analysis of bone loss indicated that gender, bicortical stabilization, bone quality, and healing time were predictors of bone loss for the first year of loading but not for the ensuing years. Prosthetic maintenance included fractured components, denture relining, and replacement of prostheses. On average, the longevity of overdenture prostheses was 12 years, and laboratory relining was necessary every 4 years. CONCLUSION: This study confirmed the long-term outcome success of patients treated with design-specific overdenture prostheses supported by Br?nemark implants. However, prosthetic maintenance was required, a fact that should be discussed with patients prior to treatment.     

Multicenter retrospective study of cement-retained implant-supported anterior partial prostheses: success and restoration evaluation

PURPOSE: The aim of this multicenter study was to evaluate implant success and restorative complications of cement-retained implant-supported anterior partial prostheses in Jordan. MATERIALS AND METHODS: A retrospective study of all implants with a minimum of 1-year follow-up were used to support fixed, cement-retained restorations from April 2000 until March 2007. The cement-retained implants were loaded with either single- or multiple-tooth replacements. The Fisher exact test was performed to test the presence of any statistically significant difference in success concerning gender or arch of placement. RESULTS: Eighty-seven implants were placed in the anterior region of the mandible or maxilla in 49 patients at multiple clinical practices in Jordan. The age of the patients ranged from 17 to 85 years. Eighteen implants were placed in the mandible and 69 in the maxilla. Three maxillary implants in 2 male patients had 3-mm horizontal bone loss. Those 3 implants are still functioning and were considered surviving implants but not successful implants. Therefore, the implant cumulative survival rate for both arches and genders was 100%. The implant cumulative success rate was 95.78%. Three crowns (maxillary) were dislodged. No significant differences were revealed regarding gender or arch of placement (P > .05). CONCLUSIONS: Cement-retained implants exhibited high survival and success rates among a Jordanian population.     

Multicenter retrospective analysis of the solid-screw ITI implant for posterior single-tooth replacements

PURPOSE: This report involves the retrospective analysis of ITI implants placed and/or restored by a group of 7 clinicians located throughout the United States (5 periodontists and 2 prosthodontists). MATERIALS AND METHODS: Six hundred seventy-five posterior single-tooth implants were restored in 471 patients (average time of loading 21.30 months, with a range of 1 to 78 months). Three hundred seventy implants and 71 implants were placed in mandibular and maxillary molar sites, respectively, and 108 and 126 were placed in mandibular and maxillary premolar sites, respectively. RESULTS: A cumulative survival rate of 99.1% was obtained for all sites (6 failures). The survival rates for individual sites were as follows: 98.4% mandibular molars, 100% maxillary molars, 100% mandibular premolars, and 100% maxillary premolars. "At-risk" implants (1 to 2 mm of radiographic bone loss) were noted at 5 sites. DISCUSSION: Minimal restorative problems were found with either screw-retained (n = 71) or cemented restorations on solid abutments (n = 600); 80.3% of screw-retained and 98.2% of cemented restorations were free of complications, respectively. Patient satisfaction scores were high (97.4%) as determined by the Patient Satisfaction Questionnaire. CONCLUSION: The data suggest that solid-screw (4.1 or 4.8 mm wide) ITI implants can be a satisfactory choice for posterior single-tooth restorations.     

Early versus late loading of unsplinted TiUnite surface implants supporting mandibular overdentures: a 2-year report from a prospective study

The aim of this study was to evaluate the clinical performance of the implants supporting mandibular overdentures, and to investigate the prosthodontic outcomes of the mandibular implant overdentures. Twenty edentulous patients participated in this study. Forty implants were placed in the canine areas of the mandibles of all patients using the 1-stage approach. New maxillary complete dentures and the mandibular implant overdentures were delivered to 10 patients in the test group 1 week after surgery, while new maxillary and mandibular complete prostheses were delivered to 10 patients in the control group. These conventional mandibular prostheses were converted to mandibular implant overdentures 3 months after surgery. No implants were lost neither in test nor in control group. The average ISQ values between the two groups were not statistically significant during 2 years (P > 0.05). The average marginal bone resorptions were 0.4 and 0.5 mm for the test and the control group after 2 years. The number of appointments required for the prosthodontic maintenance of the mandibular implant overdentures in the first year was higher than that in the second year, which was statistically significant(P < 0.001). The results of the study suggest that the 1-week early loading approach does not adversely influence the clinical performance of the implants supporting mandibular overdentures.     

Success and failure rates of osseointegrated implants in function in regenerated bone for 72 to 133 months

PURPOSE: Guided bone regenerative therapy has become a significant component of clinical implant practice. Initial reports have demonstrated success rates of implants in regenerated bone under function comparable to the success rates of implants placed in native nonregenerated host bone. This report documents the success and failure rates of osseointegrated implants placed in regenerated bone for up to 133 months in function. MATERIALS AND METHODS: A retrospective analysis of a group of 607 titanium plasma-sprayed cylindric implants placed in regenerated bone, the success and failure rates of which were previously reported at 6 to 51 months in function, were assessed. RESULTS: The implants demonstrated cumulative success rates of 97.2% for the maxilla and 97.4% for the mandible, yielding an overall cumulative success rate of 97.4% for up to 133 months in function. DISCUSSION AND CONCLUSIONS: Titanium plasma-sprayed osseointegrated implants of various diameters, lengths, and designs, utilized in a variety of clinical scenarios, demonstrated functional cumulative success rates comparable to those of implants placed in nonregenerated host bone for extended periods of time in this patient population.     

Early functional loading of unsplinted roughened surface implants with mandibular overdentures 2 weeks after surgery

Background: Before early functional loading of unsplinted implants with mandibular overdentures can become widespread, more clinical studies are needed to investigate the success of the approach. Purpose: To evaluate the success rates of two types of roughened titanium surface implants with early 2‐week functional loading of paired mandibular interforaminal implants with overdentures. Materials and Methods: Random allocation divided 24 strictly selected edentulous participants into two groups, with each group to receive a different implant system (ITI Dental Implant System, Straumann AG, Waldenburg, Switzerland; or Southern Implant System, Southern Implants, Irene, South Africa). Two implants were placed in the anterior mandible of all participants using one‐stage standardized surgical procedures. Previously constructed conventional mandibular dentures (opposing maxillary complete dentures) were temporarily relined and worn by the participants for the first 2 weeks; participants used a soft diet. Two weeks after implant surgery and following some mucosal healing, the mandibular dentures had the tissue conditioner removed and the appropriate matrices included for an unsplinted prosthodontic design. Results: No implant from either group was lost. Resonance frequency analysis (RFA) indicated higher primary stability at surgery for the Southern group than for the ITI group, with a statistically significant difference between the groups throughout the study period. The drop in RF values between surgery and 6 weeks was significant and was greater for the Southern group. RFA also indicated stabilized osseointegration between 6 to 12 and 12 to 52 weeks, with no participant showing any decrease in those values over time. Participants with type 3 bone showed a significant improvement in RF values between 12 and 52 weeks, eventually matching those of participants with type 2 bone. There were no significant differences in marginal bone loss, periimplant parameters, or prosthodontic maintenance between the groups over the study period. Conclusions: Using only strict patient selection criteria, 1‐year follow‐up data indicate that early functional loading of ITI and Southern implants with mandibular two‐implant overdentures is possible as early as 2 weeks after implant surgery.     

Maxillary overdentures retained by splinted and unsplinted implants: a retrospective study

The purpose of this retrospective study was to evaluate the clinical performance of and patients' satisfaction with maxillary overdentures retained by splinted and unsplinted implants. Patients who had been treated with maxillary implant-retained overdentures because of functional problems with conventional complete dentures were identified and invited to participate in the study. A total of 16 patients fulfilled the enrollment criteria and agreed to participate. Eleven patients were treated with bar-retained overdentures with 3 to 6 clips (mean follow-up 32 months), and 5 patients wore overdentures retained by 2 to 6 ball attachments (mean follow-up 54 months). All subjects were satisfied with their prostheses, and most subjects experienced improvement in their oral function after treatment with implant-retained overdentures. At the time of clinical examination, 92% (n = 77) of the 84 implants placed were functioning satisfactorily. The cumulative survival rate for the implants after 72 months was 90%. Loss of bone support correlated with peri-implant probing depth (r = 0.29; P < .02). No differences in mean bone loss between the subjects with ball-retained or bar-retained overdentures were found. The presence of plaque or peri-implant bleeding was not associated with the type of attachment.     

Rehabilitation of mandibular edentulism by single crystal sapphire implants and overdentures: 3–12 year results in 86 patients. A dual center international study.

86 patients, in 2 Scandinavian centers, participated in a prospective study of mandibular edentulism, treated with overdentures supported by Bioceram sapphire implants. Implant success and prosthesis stability as well as parameters for peri‐implant health were evaluated. Masticatory function and complications were also documented. The study began in 1982 and clinical treatment of the last patients was completed in 1991. The patients have been followed for at least 3 years, and up to 12 years. 4 patients were lost to follow‐up. Of the initial 324 implants, 7 implants failed before prosthetic treatment. 3 patients lost 1 implant each within the 1st year, and 4 patients lost all 4 implants. 16 implants were lost between 36 and 42 months in function, due to lack of osseointegration and pain. The loss of implants could be attributable to an association, not statistically verified, between bone quality and anatomy, with heavy smoking as a risk factor. Based on the remaining implants, the cumulative implant success rates were 95.2%, 91.3%, 91.3%, 91.3% at 3, 5, 10 and 12 year follow‐up, respectively. The cumulative success rates for overdentures were 96.4%, 92.8%, 92.8% and 92.8% respectively, for the same follow‐up periods. Indices for the health of the peri‐implant mucosa disclosed no serious inflammatory reactions in the surrounding soft tissues. Patient satisfaction with this form of oral rehabilitation was high in all but 2 patients who experienced discomfort.