Glenn J. Wolfinger

Immediate loading of Brånemark implants in edentulous mandibles: a preliminary report.

A study involving the immediate loading of Brånemark implants in the edentulous mandibles of 10 patients is reported. The design involved the immediate loading of four widely distributed implants with a transitional fixed implant-supported prosthesis at first-stage surgery, avoiding the need for a removable prosthesis. A sufficient number of additional implants are allowed to heal in the conventional manner to provide sufficient support for a definitive fixed prosthesis even if all of the immediately loaded implants fail. Preliminary results have been favorable, with all patients functioning with a fixed implant prosthesis from the day of first-stage surgery. (Implant Dent 1997;6:83–88)

Dental Implants in the Diabetic Patient: A Retrospective Study

It has become increasingly common for controlled diabetic patients to be considered as candidates for dental implants. This study reports on the results of placing implants in 34 patients with diabetes who were treated with 227 Brånemark implants. At the time of second-stage surgery, 214 of the implants had osseointegrated, a survival rate of 94.3%. Only one failure was identified among the 177 implants followed through final restoration, a clinical survival rate of 99.9%. Screening for diabetes and trying to ensure that implant candidates are in metabolic control are recommended to increase the chances of successful osseointegration. Antibiotic protection and avoidance of smoking should also be considered.

A Retrospective Analysis of 800 Brånemark System Implants Following the All‐on‐Four™ Protocol

PURPOSE The purpose of this study was to retrospectively evaluate implant survival rates in patients treated with the All-on-Four™ protocol according to edentulous jaws, gender, and implant orientation (tilted vs. axial). MATERIALS AND METHODS All Brånemark System implants placed in patients following the All-on-Four™ protocol in a single private practice were separated into multiple classifications (maxilla vs. mandible; male vs. female; tilted vs. axial) by retrospective patient chart review. Inclusion criteria consisted of any Brånemark System implant placed with the All-on-Four™ protocol from the clinical inception (May 2005) until December 2011. Life tables were constructed to determine cumulative implant survival rates (CSR). The arches, genders, and implant orientations were statistically compared with ANOVA. RESULTS One hundred fifty-two patients, comprising 200 arches (800 implants) from May 2005 until December 2011, were included in the study. Overall implant CSR was 97.3% (778 of 800). Two hundred eighty-nine of 300 maxillary implants and 489 of 500 mandibular implants survived, for CSRs of 96.3% and 97.8%, respectively. In male patients, 251 of 256 implants (98.1%) remain in function while 527 of 544 implants (96.9%) in female patients survived. Regarding implant orientation, 389 of 400 tilted implants and 389 of 400 axial implants osseointegrated, for identical CSRs of 97.3%. All comparisons were found to be statistically insignificant. The prosthesis survival rate was 99.0%. CONCLUSIONS The results from this study suggest that edentulous jaws, gender, and implant orientation are not significant parameters when formulating an All-on-Four™ treatment plan. The high CSRs for each variable analyzed demonstrate the All-on-Four™ treatment as a viable alternative to more extensive protocols for rehabilitating the edentulous maxilla or mandible.

Guided implant placement and immediate prosthesis delivery using traditional Brånemark System abutments: a pilot study of 23 patients.

Purpose:The aim of this study is to demonstrate the accuracy and clinical precision of a guided surgery protocol by using traditional Brånemark System abutments in conjunction with a prefabricated all-acrylic provisional prosthesis that is immediately installed after implant placement. Materials:All presurgical methods in this treatment follow the standard NobelGuide protocol with the exception of the laboratory phase. Once the master cast is retroengineered from the surgical template, traditional Brånemark System abutments were secured onto the implant replicas (master cast) and an all-acrylic provisional prosthesis was constructed at the abutment level. The typical abutments used with this protocol, adjustable Guided Abutments, were not used. Results:Twenty-three patients were treated in this pilot study. Via the surgical template, all implants were placed to the desired depth as planned in the virtual implant planning program. After the traditional Brånemark Abutments were installed, the provisional prosthesis was delivered and occlusion verified. The prosthesis fit was checked at abutment level clinically and radiographically. Conclusion:This report shows the extreme accuracy of this guided surgery protocol. If each step of this protocol is followed precisely, it is possible to deliver a prefabricated prosthesis built to traditional Brånemark System Abutments, which is extremely favorable for long-term patient and prosthesis management.

A long-term retrospective analysis of survival rates of implants in the mandible.

PURPOSE To retrospectively analyze the survival rate of endosseous dental implants placed in the edentulous or partially edentulous mandible over a long-term follow-up period of 10 years or more. MATERIALS AND METHODS The charts of patients who underwent mandibular implant placement at a private prosthodontics practice and received follow-up care for 10 years or more were included in this study. Implants were examined according to the following study variables: patient sex, patient age, degree of edentulism (fully vs partially edentulous), implant location, time of loading (delayed vs immediate), implant size and type, bone quality, prosthesis type, and the presence of other implants during placement. RESULTS The study sample was composed of 2,394 implants placed in 470 patients with 10 to 27 years of follow-up. Of these 2,394 implants, 176 failed, resulting in an overall cumulative survival rate (CSR) of 92.6%. A total of 1,482 implants were placed in edentulous mandibles, and 912 implants were placed in partially edentulous mandibles, with CSRs of 92.6% and 92.7%, respectively. Comparisons of the study variables with respect to CSR were largely nonsignificant. However, there were significant differences in CSRs between anterior vs posterior locations and rough- vs smooth-surfaced implants in addition to some prosthesis types, ages, and bone qualities. The overall CSR of 92.6% in the present study is high and comparable to survival rates observed in previous long-term analyses of mandibular implants. The significant differences observed between implant locations, patient age groups, bone qualities, and prostheses were not suggestive of any remarkable trends. CONCLUSION Patient sex, age, degree of edentulism, implant location, time of loading, implant size and type, bone quality, prosthesis type, and the presence of multiple implants did not result in any significant effect on long-term implant survival. The CSR observed after 10 to 27 years of follow-up in a single private prosthodontic center was high (92.6%) and supports the use of endosseous dental implants as a long-term treatment option for the rehabilitation of the edentulous and partially edentulous mandible.

A Retrospective Comparison of Implants in the Pterygomaxillary Region: Implant Placement with Two-Stage, Single-Stage, and Guided Surgery Protocols

PURPOSE Implants placed into the pterygomaxillary region allow for increased posterior support and a full complement of teeth without the need for distal cantilevers. With advancements in research and technology, implant delivery has evolved from the traditional two-stage procedure to immediate loading freehand and guided surgical template protocols. The purpose of this retrospective study is to determine if there is a significant difference in implant survival rates between these protocols. MATERIALS AND METHODS All pterygomaxillary implants placed in a single private practice from September 1985 to July 2011 were categorized into three separate classifications (two-stage freehand, single-stage freehand, or single-stage guided) by retrospective chart review. Life tables were constructed to determine the cumulative survival rates (CSR), and ANOVA was used to identify statistical significance. RESULTS A total of 981 patients comprising 371 males and 610 females were included in the study. Of all pterygomaxillary implants, 1,460 of 1,608 implants osseointegrated for a CSR of 90.80%. Seven hundred nine of the 825 two-stage, 624 of the 647 single-stage, and 127 of the 136 guided surgery implants osseointegrated for CSRs of 85.94%, 96.45%, and 93.38%, respectively. The comparison between two-stage and single-stage protocols was statistically significant, (P < .05) while the difference between single-stage guided versus freehand protocols was found to be statistically insignificant (P > .05). CONCLUSION The results from this retrospective study reinforce that immediate loading of pterygomaxillary implants with a provisional prosthesis is beneficial to both doctor and patient. The lower CSR for the guided surgery protocol compared with the single-stage freehand procedure is statistically insignificant, suggesting guided surgery is still a viable and recommended option for qualified patients.

Zygomatic Bone-to-Implant Contact in 77 Patients With Partially or Completely Edentulous Maxillas

PURPOSE Specifically with zygomatic implants, the bone-to-implant contact (BIC) at the zygomatic bone correlates with the survival of the implant because there is little anchorage at the alveolus. The purpose of this retrospective study was to view and measure the BIC of zygomatic implants in the zygomatic bone. MATERIALS AND METHODS The patients in this study received zygomatic implants at a single private dental implant center. All patients were treated with the same immediate-loading protocol followed by postoperative cone beam computed tomography. The scans were exported to a computer-aided design system, where the BICs could be measured digitally. The BIC was analyzed by gender, and any statistical difference was determined by analysis of variance. RESULTS The study sample was composed of 77 patients (62.3% women) receiving 173 zygomatic implants. The mean age of the sample was 59 ± 8.7 years. The mean BIC was 15.3 ± 5.6 mm (range, 4.9 to 32.9 mm) in the zygomatic bone. On average, 35.9% ± 11.7% (range, 12.2% to 67.3%) of the implant came into contact with the zygomatic bone. The average BIC in men was 16.5 ± 6.0 mm, and the average BIC in women was 14.7 ± 5.4 mm, a statistically significant difference by analysis of variance (P < .05). CONCLUSIONS Evidence from this report indicates the zygomatic BIC varies greatly from patient to patient. These data show that the typical male patient has a greater zygomatic BIC than the typical female patient; however, these data do not support the hypothesis that the zygomatic BIC influences the zygomatic implant survival rate.

A Prospective Analysis of Immediate Provisionalization of Single Implants

Purpose: The purpose of this prospective study was to evaluate the viability of immediately provisionalized single-tooth implants. Materials and Methods: One hundred forty patients (86 female, 54 male) with a mean age at implant placement of 45 years (range, 15–88 years) needing singletooth replacement, were treated between July 1999 and December 2004. Single-tooth implants were placed and provisionalized the day of the surgery. All implants were manufactured by Nobel Biocare (Yorba Linda, CA) and had multiple diameters and configurations. The majority of the implants used in this study had oxidized titanium surfaces. The contours of the restorations were designed to mimic the original teeth and root forms. The morphology of the restorations provides support of the labial gingiva. Results: Over 5.5 years, 164 implants were placed and immediately provisionalized. Sixty-four implants were placed immediately post extraction. Seven implants failed, yielding an overall survival rate of 95.73%. Conclusion: The application of an immediate provisionalization protocol to a single implant can be successful if the proper precautions are taken in achieving passive occlusion.

A retrospective analysis of mandibular bone height changes associated with 81 screw-retained implant-supported prostheses with distal cantilevers: a long-term follow-up analysis.

PURPOSE The aims of this study were (1) to evaluate long-term changes in bone height beneath mandibular screw-retained implant-supported prostheses with distal cantilevers and (2) to determine whether the reversal of residual ridge resorption in the posterior mandible is temporary or continues over the long term. MATERIALS AND METHODS Panoramic radiographs, obtained at surgery and at two follow-up visits, of 81 patients rehabilitated with mandibular screw-retained implant-supported prostheses with distal cantilevers supported by four, five, or six implants were followed for 5 to 19 years (overall mean follow-up, 9.00 years. Changes and trends in bone height adjacent to the most distal implant were evaluated between each follow up visit as well as from time of surgery (baseline) to the final visit using two-way analysis of variance, a two-sample t test, and piecewise linear regression. RESULTS Average bone height distal to the distal most implant at placement was 10.34 ± 6.87 mm. From baseline to the first follow-up exam, a mean bone gain of 0.68 mm was noticed, and a mean gain of 0.26 mm was observed from baseline to the second follow-up exam. A statistically significant bone gain (0.92 mm) was noticed in women (n = 49) between the first and second exams, compared to 0.33 mm in men (n = 32). Individuals experienced both bone gain and loss during the study, with an overall gain. Patients with lower initial bone height experienced greater growth, but this was not statistically significant. CONCLUSION Bone growth is associated with mandibular screw-retained implant-supported prostheses with distal cantilevers, and both bone loss and bone growth may occur in the same patient over time. Within the diverse population of this study, women experienced 2.5 times more gain in bone height than men. No correlation could be established between initial bone height and overall bone height changes.

The Retread: A Definition and Retrospective Analysis of 205 Implant-Supported Fixed Prostheses.

PURPOSE Acrylic resin teeth on fixed implant prostheses are subject to time-dependent wear. The purpose of this retrospective analysis is to evaluate and describe the management of such wear in the context of selected variables--patient gender and age, dental arch location, and opposing dentition. The clinical and dental laboratory process to replace the worn teeth is defined as a retread. MATERIALS AND METHODS A retrospective database review from a single private prosthodontic practice was carried out on all patients who had undergone a retread procedure. The patient pool included 205 arches in 194 patients (70 in men, 135 in women) with a mean age of 57.4 years (range: 19.9 to 80.5 years). The retread procedure is described. RESULTS The mean time between final prosthesis delivery and retread was 7.8 years (range: 1.1 to 22.9 years). Statistical analysis was significant according to dental arch and opposing dentition. A statistical difference was also noted in patients undergoing multiple retread procedures, with a reduction in time between the subsequent procedures. CONCLUSION Acrylic resin components of implant-supported hybrid prostheses wear over time and are influenced by a combination of the nature of the opposing dentition and patient habits. The dental laboratory process to retread the implant-supported framework is important for long-term patient care and maintenance of an appropriate vertical dimension of occlusion.