Implants – Review of dental implants. Synopsis

Advanced Surgery and Implant Literature Review

 

Rapid Search Terms

Longitudinal studies: survival and success of implants

References:

Book Chapters

  • Lang and Salvi. Implants in Restorative Dentistry (CH 52). Clinical Periodontology and Implant Dentistry, Lindhe, J.; Lang, K. 5th Edition, 2008, Blackwell Munksgaard (Volume 2).
  • Misch. Rational for Dental Implants. (CH 1). pp 3-25. Contemporary Implant Dentistry, Misch, C.E., 3rd Edition, 2008, Mosby Year Book.
  • Cochran, D: Implants Therapy I. Proceeding of the 1996 World Workshop in Periodontics 1:707-795, 1996
  • Fritz, M: Implants Therapy II. Proceedings of the 1996 World Workshop in Periodontics 1: 796-815,1996

Journals:

  1. Albrektsson T et al: The long term efficacy of currently used dental implants: A review and proposed criteria of success. Int J Oral Max Implants 1:11-26, 1986
  2. Misch CE, Perel ML, Wang HL, et al. Implant success, survival, and failure: the International Congress of Oral Implantologists (ICOI) Pisa Consensus Conference. Implant Dent. 2008 Mar;17(1):5-15.
  3. Klokkevold P et al: Current status of dental implants: A periodontal perspective. Int J Oral Maxillofac Implants 15: 56-65, 2000
  4. Salinas TJ, Eckert SE. In patients requiring single-tooth replacement, what are the outcomes of implant- as compared to tooth-supported restorations? Int J Oral Maxillofac Implants. 2008 Jan-Feb;23(1):56.
  5. Simonis P, Dufour T, Tenenbaum H. Long-term implant survival and success: a 10-16-year follow-up of non-submerged dental implants. Clin Oral Implants Res. 2010 Jul;21(7):772-7.
  6. Boioli L et al: A meta-analytic, quatitative assessment of osseointegration establishment and evolution of submerged and non-submerged endosseous titanium oral implants. Clin Oral Implants Res. 12: 579-88, 2001
  7. Ueda T, Kremer U, Katsoulis J, Mericske-Stern R. Long-term results of mandibular implants supporting an overdenture: implant survival, failures, and crestal bone level changes. Int J Oral Maxillofac Implants. 2011 Mar-Apr;26(2):365-72.

Abstracts:

Topic:Implant Success


Authors:Albrektsson T, Zarb, Worthington, Eriksson

Tittle: The long term efficacy of currently used dental implants: A review and proposed criteria of success.

Source: Int J Oral Max Implants

Type: Discussion article

Keywords: success, osseointegration

Purpose: This paper is an attempt to evaluate currently used dental implant systems and to propose criteria of success.

Discussion:

Observations: Osseointegration: is a histological definition, and only partially a clinical and radiographic one. An implant can only be judged as osseointegrated in the context of a continuum of observation, since undermining interfacial changes may be gradual, and not evident at the radiographic resolution level at least in the short term.

Topic:Implant success, survival, and failure


Authors:Misch CE, Perel ML, Wang HL

Title:Implant success, survival, and failure: the International Congress of Oral Implantologists (ICOI) Pisa Consensus Conference.

Source:Implant Dent. 2008 Mar;17(1):5-15.

Type:Consensus discussion

Keywords:implant clinical success, implant clinical survival, implant clinical failure

Purpose: To propose 4 clinical categories that contain conditions of implant success, survival, and failure.

Discussion:

Survival conditions:

Satisfactory survival: an implant with less than ideal conditions, yet does not require clinical management

Compromised survival: implants with less than ideal conditions, which require clinical treatment to reduce the risk of implant failure

Implant failure: implants that require removal or have already been lost

Implant success: should include a time period of at least 12 months loading. Early implant success is 1-3 years, intermediate 3-7 years, long term success more than 7 years

Clinical indices:

Pain: Once implant has achieved primary healing, absence of pain under vertical or horizontal forces is a primary subjective criterion. Pain should not be associated with the implant after healing. Usually, pain form the implant body does not occur unless the implant is mobile and surrounded by inflamed tissue or has rigid fixation but impinges on the a nerve. Pain during function can place the implant in the failure category. Sensitivity during function may place the implant in the survival category and may warrant clinical treatment.

Mobility: Lack of clinical movement does not mean the true absence of mobility. Lack of mobility usually means that at least a portion of the implant is in direct contact with bone, although the percentage of bone contact cannot be specified. A clinically mobile implant indicates the presence of connective tissue between the implant and bone (failure).

Radiographic crestal bone loss: The marginal bone around implant crestal region is usually a significant indicator or implant health. The Pisa Consensus suggests that the clinical assessment for each implant monitors marginal bone loss in increments of 1.0 mm. The bone loss measurement should be related to the original marginal bone level at implant insertion, rather than to a previous measurement.

Probing depths: Probing depths may be of little diagnostic value unless accompanied by signs and/or symptoms. It is of benefit to probe and establish a baseline measurement after the initial soft tissue healing around the permucosal aspect of the implant. Increases in this baseline measurement over time most often represents marginal bone loss.

Peri-implant disease: Exudate or an abscess around an implant indicates exacerbation of the peri-implant disease and possible accelerated bone loss. An exudate persisting more than 1-2 weeks usually warrants surgical revision of the peri-implant area to eliminate causative elements.

Conclusion:

Implant success is as difficult to describe as the success criteria for a tooth. Implant failure is easier to describe than implant success or survival and may consist of a variety of factors. Any pain, vertical mobility, and uncontrolled progressive bone loss warrant implant removal.

Topic: Periodontal considerations around dental implants


Authors: Klokkevold P et al

Title: Current status of dental implants: A periodontal perspective

Source: Int J Oral Maxillofac Implants 15: 56-65, 2000

Type: Review

Keywords: dental implants

Purpose: To provide an overview of the current status of implants as related to the practice of periodontics.

Discussion:

RESTORING FORM, FUNCTION AND ESTHETICS:

The prosthetic position was not thought to be critical to the success of implants, and therefore it was not a major consideration. However due to the esthetic demands of patients, implant therapy has become increasingly focused on prosthetically driven implant position. Several new evidence-based guidelines emerged from prosthetically driven implant positioning, including the need to reconstruct hard and soft tissues that had been lost, so a bone augmentation or bone regenerative procedure had to be considered.

PERI-IMPLANT PATHOLOGY AND IMPLANT FAILURE

Peri-implant pathology, or more specifically periimplant bone loss, has been attributed to several different factors, including poor surgical management, failure to achieve osseointegration, premature loading, biomechanical overload, peri-implant infection, and impaired host response.

PERI-IMPLANT TISSUE ANATOMY FROM THE PERIODONTAL PERSPECTIVE

Osseointegrated dental implants do not have any connective tissue fiber attachments. Osseointegrated dental implants by definition do not have any soft tissues intervening between the implant surface and the bone. There are no collagen fibers attached to the implant surface. There is a connective tissue network of fibers around the implant coronal to the level of supporting bone. The supra-bony connective tissue surrounding the implant is made up of circumferential fibers that run parallel to the implant surface.

BIOLOGIC DIMENSION OF SOFT TISSUES AROUND IMPLANTS

Regardless of the type of implant used and the soft tissue dimensions at the time of placement, the authors found that a 2-mm-long junctional epithelium and a 1-mm zone of connective tissue were consistently established.

PERI-IMPLANTITIS

Peri-implantitis is defined as an inflammatory process affecting the tissues around an osseointegrated implant in function that results in loss of supporting bone, while peri-implant mucositis is an inflammatory process distinguished from periimplantitis by the lack of bone loss.

TREATMENT OF PERI-IMPLANTITIS

The most important aspect of treatment for peri-implantitis is to stop the progression of bone loss by controlling bacterial infection. As with periodontal therapy, the goal of surgical therapy is complete debridement of the defect, decontamination of the implant surface, and possibly removal of any porous implant surface coatings. Once the inflammatory disease process is controlled, it is possible to attempt regenerative procedures. In addition to bacterial infection, biomechanical overload has been shown to contribute to periimplant bone loss. Bone loss associated with biomechanical overload is most frequently found to be localized around the coronal aspect of the bone-implant interface.

Radiographs should be taken periodically to evaluate potential loss of bone. It has been well established that the amount of bone loss around Brånemark-type implants is approximately 1 to 1.5 mm in the first year after loading and 0.1 mm annually thereafter.

At regular intervals (every 3 to 6 months), implant abutment/restoration surfaces should be debrided of plaque and calculus accumulations.

Conclusion:The combination of in-depth biologic knowledge together with extensive surgical training has given the periodontist the skills to provide the highest quality care to patients around the world.

Topic:Implants vs Fixed Partial Dentures


Title: In patients requiring single-tooth replacement, what are the outcomes of implant- as compared to tooth-supported restorations?

Author: Salinas TJ, Eckert SE.

Source: Int J Oral Maxillofac Implants. 2008 Jan-Feb;23(1):56.

Type: Systematic review

Keywords: comparative study, prosthodontics, implants compared to FPD, FPD, restorative planning

Purpose:The study provides a systematic review of the literature to determine the long-term survival characteristics of single implant-supported crowns and fixed partial dentures.

Materials and Methods:

A search of the MEDLINE, EMBASE, and Cochrane Collaboration databases was conducted to identify articles that compared survival and success of fixed partial dentures and single implant-supported crowns. In addition to comparative cohort studies, articles that pertained specifically to single implant-supported crowns or fixed partial dentures were included in this review. Inclusion criteria for implant and fixed partial denture articles included a minimum 2-year study, primary publication in the English language, a minimum of 12 implants, implants designed to osseointegrate, and inclusion of data regarding implant and prosthetic performance. Data were analyzed using cumulative proportions of survival and success for both prosthetic types and for individual implants. Wilson score method was used to establish 95% confidence intervals for each population. The chi-square test for homogeneity was performed.

Results: The literature search failed to identify any articles that directly compared survival or success of single implant-supported restorations with fixed partial dentures. Following the search criteria, and independent analysis by reviewers, 51 articles were identified in the implant literature (agreement, 95.42%; kappa coefficient, 0.8976), and 41 were identified in the fixed partial denture literature (agreement, 90.97%; kappa coefficient, 0.7524). Pooled success of single-implant restorations at 60 months was 95.1% (CI: 92.2%-98.0%), while fixed partial dentures of all designs exhibited an 84.0% success rate (CI: 79.1%-88.9%).

Conclusions: Tthis systematic review of the scientific literature failed to demonstrate any direct comparative studies assessing clinical performance of single implant-supported crowns and tooth-supported fixed partial dentures. The analysis suggested differences at 60 months between survival of implant-supported single crowns and natural tooth-supported fixed prostheses when resin-bonded and conventionally retained fixed prostheses were grouped. This difference disappeared when implant-supported single crowns were compared with conventionally retained fixed partial dentures at 60 months. For other time periods, direct comparative data were unavailable.

Topic: Implant survival and success rate


Authors: Simonis P, Dufour T, Tenenbaum H.

Title: Long-term implant survival and success: a 10-16-year follow-up of non-submerged dental implants.

Source: Clin Oral Implants Res. 2010 Jul;21(7):772-7.

Type: Retrospective study

Keywords: implant survival, implant success, cumulative survival rate

Purpose: To evaluate the long-term results of dental implants using implant survival and implant success as outcome variables.

Methods: Of the 76 patients who received 162 implants of the Straumann Dental Implant System during the years 1990-1997, 55 patients with 131 implants were recalled 10-16 years after implant placement for a complete clinical and radiographic examination, followed by a questionnaire that examined the degree of satisfaction. The incidence of biological and technical complications has been carefully analyzed for each implant. Success was defined as being free of all these complications over the entire observation period. Associated factors related to peri-implant lesions were analyzed for each implant.

Results: The long-term implant cumulative survival rate up to 16 years was 82.94%. The prevalence of biological complications was 16.94% and the prevalence of technical complications was 31.09%. The cumulative complication rate after an observation period of 10-16 years was 48.03%, which meant that substantial amounts of chair time were necessary following implant placement. The majority of implant losses and biological complications were concentrated in a relatively small number of patients.

Conclusion: Despite a relatively high long-term survival rate, biological and technical complications were frequent. Patients with a history of periodontitis may have lower implant survival rates than patients without a history of periodontitis and were more prone to biological complications such as peri-implant mucositis and peri-implantitis.

 

Topic: Platform-Switched laser-microchannel implants submerged and non-submerged implants

Authors: Boioli L et al

Title: A meta-analytic, quatitative assessment of osseointegration establishment and evolution of submerged and non-submerged endosseous titanium oral implants

Source: Clin Oral Implants Res. 12: 579-88, 2001
Type: Meta-analysis

Keywords:dental implants, submerged, non-submerged, life table analysis, survival rates, review

Background: Two implant placement methods are used in oral implantology: submerged (S, two-stage surgical procedure) and non-submerged (NS, one-stage surgery). However, a quantitative assessment of their influence on implant osseointegration, summarising the whole present experience, is not directly possible, owing to the lack of normalisation of the published results

Purpose: to help improve the quantitative assessment of this influence by defining normalisation criteria, which would allow the pooling of the results of the studies meeting them and, hence, the statistical treatment of the overall longitudinal results.

Materal and methods:

  • A survey of the literature was performed on studies report on implants placed either with a submerged (S) or a non-sub- merged (NS) procedure. Only root-analogue, threaded implants, exclusively made of titanium, were considered.
  • Among the studies meeting all criteria, 65 concerned S implants and 18 NS implants. One study concerned both S and NS implants.
  • Survival life tables are established (up to 15 and 10 years respectively for S and NS implants placed in normal situations) for extended samples (13049 S and 5515 NS implants).
  • Early (before loading) failure rates and 95% confidence level ranges of cumulative implant survival rates (CSR) have been evaluated.

Results:

  • Both categories match current survival requirements, but with a quite different behavior over time.
  • NS implants, while osseointegrating better initially, are subject to causes of osseointegration loss, which persist over a longer period of time.
  • Implant design characteristics (including the type of surface) seem to be more relevant than the placement procedure for the implant’s behavior.

Conclusion:

  • S and NS implants give acceptable results in terms of survival, and for both categories (but especially for S implants) the placement stage remains a discernible individual cause of failure
  • S implants have been studied more than NS implants, and present less dispersed results; NS implants are particularly affected by a reduced sample after 5–6 years of observation: the findings for this period still require confirmation;
  • NS implants seem to show a better osseointegration establishment, but, unlike S implants, an osseointegration loss process lasting for a longer period of time; subject to further confirmation, the type of placement procedure seems to be of lesser importance for the behavior of the implants, compared with implant design characteristics, including those related to their surface.

 

Topic: implant-supported overdentures


Authors: Ueda T, Kremer U, Katsoulis J, Mericske-Stern R

Title:Long-term results of mandibular implants supporting an overdenture: implant survival, failures, and crestal bone level changes

Source: Int J Oral Maxillofac Implants. 2011 Mar-Apr;26(2):365-72.

Type: clinical

Keywords: crestal bone loss, dental implants, implant surgical, long-term follow-up study, manifestation of failures,

Purpose:To summarize the long-term clinical observations of edentulous patients treated with mandibular implant-supported overdentures.

Methods: 147 edentulous patients, fairly healthy, admitted to treatment with mandibular implant overdentures in university of Bern, Switzerland. The treatment plan was to connect the dentures to only two implants by means of single ball anchors or bars; in patients with severely reduced ridge (≤ 8mm) or narrow and curved anterior mandible, three implants would be placed. Strauman implants in all pts. One-part implants with 7,9,11,13 or 15 mm, and two-part implants 6,8,10,12, or 14 mm, all 3.3 or 4.1 mm diameter. Non-submerged, single-stage placement, unloaded healing time 3 months then prosths fabricated. Regular maintenance care was provided at least one time per year. The cumulative implant survival rate was calculated. Implant failures were described according to clinical signs at the time of removal and related to the patient’s specific history. Crestal bone measurements were performed using computer software based on panoramic radiographs.

Results:147 patients with 314 implants were evaluated for 10 to 24 years. Of these, 101 patients were still available. Success rate could not be calculated due to absence of regular radiographs to confirm a minimum annual bone loss. Thirteen implants failed during the observation period, resulting in a cumulative survival rate of 85.9% after 24 years. The reasons for removal of implants were peri-implantitis (two implants) and mobility (11 implants). Mean crestal bone loss was 0.54 ± 0.7 mm per implant site after an average observation time of 16.5 ± 3.9 years. The duration of loading had a statistically significant effect on bone loss. NSSD among different subgroups of implants.

Conclusion:The data exhibit a satisfactory survival rate of implants. An individual analysis of implants with late failures did not reveal a typical failure pattern, but loss of implants without signs of infection was more frequent than loss of implants with signs of peri-implantitis.