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.

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.

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.

Chlorhexidine. An adjunct to periodontal therapy

Chlorhexidine is an effective antimicrobial agent. Its application can enhance periodontal therapy. The pharmacology of chlorhexidine and suggestions for its use are outlined. In addition, its potential for inducing cancer and bacterial resistance are discussed.