Group 2 ITI Consensus Report: Prosthodontics and implant dentistry.

OBJECTIVES: Working Group 2 was convened to address topics relevant to prosthodontics and dental implants. Systematic reviews were developed according to focused questions addressing (a) the number of implants required to support fixed full-arch restorations, (b) the influence of intentionally tilted implants compared to axial positioned implants when supporting fixed dental prostheses (FDPs), (c) implant placement and loading protocols, (d) zirconia dental implants, (e) zirconia and metal ceramic implant supported single crowns and (f) zirconia and metal ceramic implant supported FDPs. MATERIALS AND METHODS: Group 2 considered and discussed information gathered in six systematic reviews. Group participants discussed statements developed by the authors and developed consensus. The group developed and found consensus for clinical recommendations based on both the statements and the experience of the group. The consensus statements and clinical recommendations were presented to the plenary (gathering of all conference attendees) and discussed. Final versions were developed after consensus was reached. RESULTS: A total of 27 consensus statements were developed from the systematic reviews. Additionally, the group developed 24 clinical recommendations based on the combined expertise of the participants and the developed consensus statements. CONCLUSIONS: The literature supports the use of various implant numbers to support full-arch fixed prostheses. The use of intentionally tilted dental implants is indicated when appropriate conditions exist. Implant placement and loading protocols should be considered together when planning and treating patients. One-piece zirconia dental implants can be recommended when appropriate clinical conditions exist although two-piece zirconia implants should be used with caution as a result of insufficient data. Clinical performance of zirconia and metal ceramic single implant supported crowns is similar and each demonstrates significant, though different, complications. Zirconia ceramic FDPs are less reliable than metal ceramic. Implant supported monolithic zirconia prostheses may be a future option with more supporting evidence.

Multicenter retrospective analysis of wide-neck dental implants for single molar replacement.

PURPOSE: To evaluate the predictability of Straumann wide-neck dental implants (6.5-mm prosthetic neck with a 4.8-mm endosseous sandblasted, large-grit, acid-etched-surface body) used for molar replacement. MATERIALS AND METHODS: Four hundred ninety-nine single-tooth implants were restored in molar sites in 410 patients (mean time of loading 23 months; range, 1 to 54 months) by 6 clinicians throughout the United States. Three hundred-fifty nine implants were placed in the mandible and 148 implants in the maxilla. RESULTS: The overall cumulative survival rate was 98.4% for all sites (8 failures). Survival rates of 99.2% for mandibular molars (3 failures) and 96.6% for maxillary molars (5 failures) were achieved. Survival rate of implants placed in conjunction with the bone-added osteotome procedure in the maxillary molars was 89%, with 5 of 45 procedures leading to failure. DISCUSSION: Minimal restorative problems were encountered. No cases of abutment loosening or fractures were observed for cemented restorations on solid abutments. CONCLUSION: The data suggest that the Straumann solid-screw, wide-neck implants can be a satisfactory choice for molar single-tooth replacement.

Implant placement with or without simultaneous tooth extraction in patients taking oral bisphosphonates: postoperative healing, early follow-up, and the incidence of complications in two private practices.

BACKGROUND: The development of bisphosphonate-associated osteonecrosis in patients with a history of intravenous bisphosphonate therapy is a significant cause of concern in clinical periodontal practice. The role of oral bisphosphonates in the development of bisphosphonate-associated osteonecrosis is less clear. This article documents the results of treatment of patients with a history of oral bisphosphonate therapy in two private periodontal practices. The study was a retrospective analysis of case records of patients treated as part of routine periodontal and implant treatment. METHODS: Patients with a history of oral bisphosphonate therapy of various durations were treated with implant placement and restoration or tooth extraction, immediate placement, and restoration. These patients were followed for 12 to 24 months after implant placement. The incidence of hard and soft tissue complications, including the development of osteonecrosis, was noted. RESULTS: No osteonecrosis was noted immediately postoperatively or during the follow-up period in 61 patients. One patient demonstrated a small tissue dehiscence at the 1-week postoperative examination following extraction of a mandibular first molar and simultaneous implant placement in the area of a prominent torus. No other postoperative complications were noted. All implants were functioning successfully by the Albrektsson criteria 12 to 24 months post-insertion. CONCLUSIONS: A history of oral bisphosphonate use for a mean period of 3.3 years (range, 1 to 5 years) was not found to be a contributing factor to the development of osteonecrosis following implant placement in intact ridges or tooth extraction with immediate implant placement. However, there is no doubt that larger controlled studies and retrospective reports are needed.

The radiographic bone loss pattern adjacent to immediately placed, immediately loaded implants.

PURPOSE: The purpose of this study was to evaluate radiographic bone levels adjacent to implants placed in fresh extraction sockets (ESs) and immediately loaded with a fixed full-arch provisional restoration compared to bone levels adjacent to implants placed in native bone (NB) under the same restorative conditions. MATERIALS AND METHODS: Patients with a hopeless maxillary and/or mandibular dentition had their remaining teeth extracted and 6 to 8 implants placed and restored within 72 hours. Radiographs were obtained at time 0, 3 to 6 months, and annually for 5 years. The radiographs were digitized, and the bone level changes were measured using a computer-assisted method. RESULTS: A total of 139 implants, 42 ES and 97 NB, placed in 17 patients were evaluated. The overall results indicated that for all implants (ES + NB), 0.60+/-0.71 mm of bone was lost after 6 months; 1.17 +/-0.59 mm of bone was lost after 18 months; 0.87+/-0.76 mm bone was lost after 36 months; and 1.35 +/-0.42 mm of bone was lost after 60 months. When stratifying for NB versus ES implants, it was found that for NB implants, 0.75+/- 0.21 mm of bone was lost after 6 months; 1.31 +/- 0.91 mm of bone was lost after 12 months; 1.07+/-0.21 mm of bone was lost after 36 months; and 1.45 +/- 0.49 mm of bone was lost after 54 months. For ES implants, 0.14 +/-0.33 mm of bone was lost after 6 months; 1.02 +/-0.27 mm of bone was lost after 12 months; 0.86+/-0.42 mm of bone was lost after 36 months; and 1.30 +/-0.48 mm of bone was lost after 54 months. CONCLUSION: The combination of ES and NB implants can be immediately loaded with a fixed full-arch prosthesis and remain stable for greater than 5 years. The bone loss adjacent to these implants is similar to that seen surrounding those placed and restored using traditional protocols.

Immediate loading of dental implants in the completely edentulous maxilla: a clinical report.

PURPOSE: The purpose of this article was to determine whether clinical success can be achieved with immediate loading in the completely edentulous maxilla with endosseous screw-type implants. MATERIALS AND METHODS: The study sample consisted of 34 patients who were edentulous or about to lose all remaining maxillary teeth. The patients underwent an extensive presurgical and prosthetic workup to determine whether they qualified for the study. Sufficient osseous structure to place 6 to 8 implants with a minimum length of 8 mm was required. Provisional prostheses were fabricated either chairside on the day of implant placement or in a laboratory from an impression. The abutments and temporary restorations were placed 48 to 72 hours postsurgery. RESULTS: A total of 236 implants were placed in 34 patients. Sixteen implants were lost in 11 patients; thus the survival rate was 93%. All patients subsequently received definitive maxillary restorations. DISCUSSION: The major cause of implant failure appeared to be micromotion during healing. This was the result of either a non-passively fitting restoration or noncompliance (eg, eating chewing hard foods before the implants had integrated). CONCLUSIONS: This clinical report suggests that immediate loading of implant-supported restorations in the completely edentulous maxilla was a viable treatment alternative for this patient population.

Success and failure rates of 9 mm or shorter implants in the replacement of missing maxillary molars when restored with individual crowns: preliminary results 0 to 84 months in function. A retrospective study.

BACKGROUND: The ability to utilize shorter implants in the reconstruction of the posterior maxilla would, theoretically, simplify therapy by lessening the need for augmentation surgery. The purpose of this retrospective study was to assess the success and failure rates of < or = 9 mm or shorter implants in the maxillary posterior regions restored with individual crowns. METHODS: A total of 979 implants were placed in maxillary molar positions and restored with individual crowns. The implants were followed in function for up to 84 months. The results are discussed in terms of clinical applicability and indications for use. RESULTS: The cumulative success rates in function were 94.5% for implants in the maxillary first molar positions and 98.7% for implants in the maxillary second molar positions, yielding an overall cumulative success rate of 95.1%, in function for up to 84 months. CONCLUSION: These findings suggest that non-countersunk implants of 7 to 9 mm in length may be successfully restored with single crowns in the maxillary molar region.

Immediate restoration and loading of dental implants: clinical considerations and protocols.

The use of dental implants to assist in the treatment of partial and complete edentulism is well documented. Most of the implant literature, however, reports results associated with implant survival and success when there has been adherence to rigid placement and loading protocols. Conventionally, these protocols call for the undisturbed healing of the implant-3 months in the mandible and 4 to 6 months in the maxilla. This article evaluates the literature and develops protocols for clinical procedures for the early or immediate restoration or loading of dental implants. Criteria are established for defining immediate loading, immediate restoration, early loading, and early restoration as compared to conventional protocols. The review assesses factors that influence accelerated loading and restoration decisions, including bone quality and quantity, implant design, splinting of implants, and prosthetic design. Conclusions and recommendations are made based on the experience of the consensus group charged with considering these procedures and on the current literature published on these protocols.

The effect of smoking on achieving osseointegration of surface-modified implants: a clinical report.

PURPOSE: The present study evaluated the effect of smoking on achieving initial osseointegration when surface-modified dental implants were used. MATERIALS AND METHODS: During an 18-month period in a private practice setting 1,183 implants were placed in 461 patients. The group of smokers consisted of patients who smoked a half pack or more of cigarettes per day. RESULTS: The overall success rate for smokers and non-smokers in achieving osseointegration was 98.1%. Ninety-seven percent of the implants placed in smokers osseointegrated successfully, and 98.4% of implants placed in non-smokers osseointegrated successfully (P < .05). DISCUSSION: The surface of an implant may be a critical determinant for achieving osseointegration in patients who smoke. CONCLUSION: It appears from this short-term retrospective study that smoking does not play a significant role in achieving the osseointegration of surface-modified dental implants.