Long-term follow-up of osseointegrated titanium implants using clinical, radiographic and microbiological parameters

A 10-year retrospective analysis of radiographic bone-level changes of implants supporting single-unit crowns in periodontally compromised vs. periodontally healthy patients

AIM

To compare the 10-year peri-implant bone loss (BL) rate in periodontally compromised (PCP) and periodontally healthy patients (PHP) around two different implant systems supporting single-unit crowns.

MATERIALS AND METHODS

In this retrospective, controlled study, the mean BL (mBL) rate around dental implants placed in four groups of 20 non-smokers was evaluated after a follow-up of 10 years. Two groups of patients treated for periodontitis (PCP) and two groups of PHP were created. For each category (PCP and PHP), two different types of implant had been selected. The mBL was calculated by subtracting the radiographic bone levels at the time of crown cementation from the bone levels at the 10-year follow-up.

RESULTS

The mean age, mean full-mouth plaque and full-mouth bleeding scores and implant location were similar between the four groups. Implant survival rates ranged between 85% and 95%, without statistically significant differences (P>0.05) between groups. For both implant systems, PCP showed statistically significantly higher mBL rates and number of sites with BL> or =3 mm compared with PHP (P<0.0001).

CONCLUSIONS

After 10 years, implants in PCP yielded lower survival rates and higher mean marginal BL rates compared with those of implants placed in PHP. These results were independent of the implant system used or the healing modality applied.

Risk of implant failure and marginal bone loss in subjects with a history of periodontitis: a systematic review and meta-analysis

BACKGROUND

A number of studies have suggested that implant failure and associated bone loss is greater in subjects with a history of periodontitis.

PURPOSE

To evaluate the risk for marginal bone loss around implants and implant failure in subjects with a history of periodontitis compared with periodontally healthy subjects in studies with a minimum 3-year follow-up.

MATERIALS AND METHODS

DATA SOURCES

The MEDLINE, EMBASE, and PubMed databases and relevant journals were searched up to July 1, 2008, with restriction to English language.

REVIEW METHODS

Prospective and retrospective longitudinal observational clinical studies comparing periodontal/peri-implant variables among subjects with periodontitis and subjects who were periodontally healthy were included. Screening of studies, quality assessment, and data extraction were conducted independently and in duplicate. Clarification of missing and unclear information was not sought. Outcome measures were: implant survival/failure, peri-implant parameters, changes in radiographic marginal bone level, probing pocket depth, and gingival index.

RESULTS

Seventeen potential studies were identified and six studies were accepted comparing patients with periodontitis and periodontally healthy patients treated with implants. Five studies were eligible for meta-analysis of implant survival and four studies were eligible for meta-analysis of bone loss around implants. The odds ratio for implant survival was significantly in favor of periodontally healthy patients (3.02, 95% confidence intervals 1.12-8.15). A random effects model showed more marginal bone loss in periodontitis subjects compared with periodontally healthy subjects (standard mean difference 0.61, 95% confidence interval 0.14-1.09).

CONCLUSIONS

Within the limitations of the heterogenous studies available, a moderate level of evidence indicates that periodontitis subjects were at significantly higher risk for implant failure and greater marginal bone loss as compared with periodontally healthy subjects. Prospective observational studies with subject-based designs are recommended.

Zirconia: Established facts and perspectives for a biomaterial in dental implantology

Currently, zirconia is widely used in biomedical area as a material for prosthetic devices because of its good mechanical and chemical properties. Largely employed in clinical area for total hip replacement, zirconia ceramics (ZrO(2)) are becoming a prevalent biomaterial in dentistry and dental implantology. Although titanium is used in dental implantology currently, there is a trend to develop new ceramic-based implants as an alternative to monolithic titanium. This article reviews the evolution and development of zirconia through data published between 1963 and January 2008 in English language. Articles were identified via a MEDLINE search using the following keywords: zirconia, zirconia/biocompatibility, zirconia/osseointegration, zirconia/periointegration, zirconia/review, and zirconia/bacterial adhesion or colonization. This review of the literature aims at highlighting and discussing zirconia properties in biological systems for their future use in dental implantology. In conclusion, zirconia with its interesting microstructural properties has been confirmed to be a material of choice for the "new generation" of implants, thanks to its biocompatibility, osseoconductivity, tendency to reduce plaque accumulation, and interaction with soft tissues, which leads to periointegration. However, scientific studies are promptly needed to fulfill gaps like long-term clinical evaluations of "all zirconia implants," currently leading to propose an alternative use of "hybrid systems" (i.e., titanium screw with zirconia collar) and also bacterial colonization of zirconia. Moreover, there is a permanent need for consistent information about topography and chemistry of zirconia allowing easier cross-product comparisons of clinical devices.

Biomaterial and antibiotic strategies for peri-implantitis: a review

Dental implants have 89% plus survival rates at 10-15 years, but peri-implantitis or dental implant infections may be as high as 14%. Peri-implantitis can limit clinical success and impose health and financial burdens to patients and health providers. The pathogenic species associated with periodontitis (e.g., Fusobacterium ssp, A. actinomycetemcomitans, P. gingivalis) are also associated with peri-implantitis. Incidence of peri-implantitis is highest within the first 12 months after implantation, and is higher in patients who smoke or have poor oral health as well as with calcium-phosphate-coated or surface-roughened implants. Biomaterial therapies using fibers, gels, and beads to deliver antibiotics have been used in the treatment of Peri-implantitis though clinical efficacy is not well documented. Guided tissue regeneration membranes (e.g., collagen, poly-lactic/glycolic acid, chitosan, ePTFE) loaded with antimicrobials have shown success in reosseointegrating infected implants in animal models but have not been proven in humans. Experimental approaches include the development of anti-bioadhesion coatings, coating surfaces with antimicrobial agents (e.g., vancomycin, Ag, Zn) or antimicrobial releasing coatings (e.g., calcium phosphate, polylactic acid, chitosan). Future strategies include the development of surfaces that become antibacterial in response to infection, and improvements in the permucosal seal. Research is still needed to identify strategies to prevent bacterial attachment and enhance normal cell/tissue attachment to implant surfaces.

5-year clinical experience with BTI dental implants: risk factors for implant failure

OBJECTIVES

The aims of this study were to identify with appropriate statistical tests the risk factors associated with implant failure and to evaluate the long-term survival of dental implants using implant loss as an outcome variable and performing an implant-, surgery- and patient-based analysis of failures.

MATERIAL AND METHODS

A retrospective cohort study design was used. One thousand sixty patients received 5787 BTI implants during the years of 2001-2005 in Vitoria, Spain. The potential influence of demographic items, clinical items, surgery-dependent items and prosthetic variables on implant survival was studied. Implant survival was analysed using a life-table analysis. Cox proportional hazards regression was used to identify risk factors related to implant failure.

RESULTS

Smoking habits, implant position, implant staging (two-stage implants) and the implementation of special techniques were statistically correlated with lower implant survival rates. Two risk factors associated with implant failure were detected in this study: implant staging (two-stage implants) and the use of special techniques. Additionally, the overall survival rates of BTI implants were 99.2%, 96.4% and 96% for the implant-, surgery- and patient-based analysis, respectively. Totally, 28 out from 5787 implants (0.48%) were lost during the observation period. Most of the patients with implant failure (69.6%) presented chronic or aggressive periodontitis.

CONCLUSIONS

Implant staging and the use of special techniques are risk factors for implant failure.

Reliability of findings around healthy implants in association with oral hygiene measures: a clinical, microbiological, and immunological follow-up in edentulous patients

OBJECTIVES

To assess the performance of clinical, microbiological, and immunological diagnosis of peri-implant health and the influence of professional hygiene measures on them.

MATERIAL AND METHODS

Twenty-one edentulous patients with oral implants supporting a lower overdenture were followed up over 3 months beginning 1 week before their annual recall visit. Hygiene scores, probing depth, bleeding on probing (BOP), implant stability, gingival crevicular fluid (GCF) volume, sulcular interleukin-1beta (IL-1beta) and prostaglandin E2 (PGE2) concentrations, and relative concentrations of five bacterial species (polymerase chain reaction) were investigated. Measurement variation was assessed as a function of (a) intra- and (b) inter-examiner reliability, (c) inter-implant variation in each patient, (d) time, and (e) effect of hygiene measures by accuracy, repeatability, reproducibility, and visualization with the Bland and Altman Plot.

RESULTS

Measurement means and accuracy (in parentheses) were as follows: GCF volume 1.5 microl (1.5), Interleukin-1beta 8 ng/ml (26), PGE2 63 ng/ml (185), bacteria sum score 0.2 (0.7), plaque score 1 (1), BOP score 0 (1), Periotest value -4 (3), resonance frequency analysis ISQ 66 (11), and pocket probing depth 2.3 mm (0.7). No finding exhibited any statistically significant measurement variation as explained by accuracy, repeatability, or reproducibility. Bland and Altman Plots revealed insufficient agreement for replicated BOP assessments. A short post-treatment reduction in plaque and BOP scores was visually apparent. Still, professional oral hygiene measures exerted no sustained influence on the clinical and biochemical appearance of the peri-implant tissues.

CONCLUSION

All findings except BOP showed statistically acceptable repeatability and moderate vulnerability to influences present 'chairside' in clinical practice.

Endoscopic removal of an unusual foreign body in the sphenoid sinus: an oral implant

AIM

Migration of oral implants displaced in the maxillary sinus toward the sphenoid sinus is an extremely rare event. This case report is focused on the possibility of treating such a rare complication by means of endoscopic treatment through the nasal cavity.

MATERIAL AND METHODS

A 45-year-old female patient received one oral implant for the substitution of the left first upper molar, but during the surgical procedure the implant was displaced in the maxillary sinus. Owing to a delay in treatment, a spontaneous migration of the implant in the sphenoid sinus occurred.

RESULTS

The implant was removed endoscopically through the nasal cavity: postoperative recovery was uneventful.

CONCLUSION

To the authors' knowledge, this case represents the first report concerning migration of an oral implant into the sphenoid sinus and demonstrates the reliability and safety of an endoscopically driven surgical removal of the foreign body, thus preventing potential complications with extremely low postoperative morbidity.

A comprehensive and critical review of dental implant prognosis in periodontally compromised partially edentulous patients

OBJECTIVES

The outcome of implant treatment in periodontally compromised partially edentulous patients has not been completely clarified. Therefore, the aim of the present study was to perform, applying a systematic methodology, a comprehensive and critical review of the prospective studies published in English up to and including August 2006, regarding the short-term (<5 years) and long-term (>or=5 years) prognosis of osseointegrated implants placed in periodontally compromised partially edentulous patients.

MATERIAL AND METHODS

Using The National Library Of Medicine and Cochrane Oral Health Group databases, a literature search for articles published up to and including August 2006 was performed. At the first phase of selection the titles and abstracts and at the second phase full papers were screened independently and in duplicate by the three reviewers (I. K. K., S. K., I. F.).

RESULTS

The search provided 2987 potentially relevant titles and abstracts. At the first phase of evaluation, 2956 publications were rejected based on title and abstract. At the second phase, the full text of the remaining 31 publications was retrieved for more detailed evaluation. Finally, 15 prospective studies were selected, including seven short-term and eight long-term studies. Because of considerable discrepancies among these studies, meta-analysis was not performed.

CONCLUSIONS

No statistically significant differences in both short-term and long-term implant survival exist between patients with a history of chronic periodontitis and periodontally healthy individuals. Patients with a history of chronic periodontitis may exhibit significantly greater long-term probing pocket depth, peri-implant marginal bone loss and incidence of peri-implantitis compared with periodontally healthy subjects. Even though the short-term implant prognosis for patients treated for aggressive periodontitis is acceptable, on a long-term basis the matter is open to question. Alterations in clinical parameters around implants and teeth in aggressive periodontitis patients may not follow the same pattern, in contrast to what has been reported for chronic periodontitis patients. However, as only three studies comprising patients treated for aggressive periodontitis were selected, more studies, specially designed, are required to evaluate implant prognosis in this subtype of periodontitis. As the selected publications exhibited considerable discrepancies, more studies, uniformly designed, preferably longitudinal, prospective and controlled, would be important.

Impact of supportive periodontal therapy and implant surface roughness on implant outcome in patients with a history of periodontitis

OBJECTIVE

This review searched for a relationship between susceptibility to periodontitis and peri-implantitis, with implant outcome as the primary outcome variable and supportive periodontal therapy (SPT) and implant surface roughness as confounding factors.

MATERIAL AND METHODS

It is based on a MEDLINE search up to June 2006. Only 16 fulfilled the selection criteria. The heterogeneity of the studies (e.g. periodontal status, SPT, prosthetic design, ...) rendered a meta-analysis impossible. The impact of a history of periodontitis on early implant loss was negligible. Only five papers reported sub-data for patients with different degrees of periodontitis. Four out of five papers indicate a higher incidence of late implant loss and/or marginal bone loss in patients with a history of periodontitis. This difference was most obvious for very rough implants (three papers), and/or when SPT was not organized (one paper). Other confounding factors were often neglected. Another 10 papers only reported the outcome of implants in patients with a history of periodontitis. In case of SPT and when avoiding roughened surfaces, late implant loss remained below 3%, and marginal bone loss remained low.

CONCLUSIONS

These results seem to indicate that periodontally compromised patients can be successfully treated with minimally/moderately rough implants, in the presence of SPT.

Supportive therapy and the longevity of dental implants: a systematic review of the literature

OBJECTIVE

To review systematically whether supportive implant treatment during a follow-up of at least 10 years after functional loading is effective in prevention of biological complications and fixture loss.

METHODS

A MEDLINE search was conducted for the period of 1965 to April 2006 of longitudinal clinical studies with follow-up periods after implant function of at least 10 years. Sixty-two studies were initially screened for inclusion and read in full text. Nine studies remained for the final assessment and 53 articles were thus excluded for the following reasons: (1) no information on implant maintenance was presented, (2) the number of patients/implants assessed at 10-year follow-up/final evaluation was not presented (3) fixture loss and marginal bone loss during function were not assessed at 10-year evaluation and (4) residual inflammation and/or probing pocket depth (PPD) not assessed at 10-year examination.

RESULTS

Fifty-six percent of 62 initially screened studies did not assess clinical inflammation and PPD around implants at long-term evaluation of implants. This was the most common reason for exclusion of studies. In 28% of excluded studies, there was no information on implant maintenance during follow-up. A total of 749 fixtures were included and followed for more than 10 years of functional load. Five of the included studies gave no detailed information of the assessments or the treatment at follow-up visits during the 10 years. Only in two of the included cohorts were patients enrolled in an individualized supportive program on a 3-6-month recall interval.

CONCLUSION

There are, to date, few available studies evaluating the long-term effect of supportive programs for implant patients. Based on the nine studies included, no evidence is available to suggest the frequency of recall intervals or to propose specific hygiene treatments. There is an urgent need for such studies to be initiated.

Autogenous onlay bone grafts vs. alveolar distraction osteogenesis for the correction of vertically deficient edentulous ridges: a 2?4-year prospective study on humans

OBJECTIVES

The purposes of this study were to compare: (a) autogenous bone grafts (ABG) and distraction osteogenesis (DO) for their ability in correcting vertically deficient mandibular ridges and their capability in maintaining over time the vertical bone gain obtained before and after implant placement; and (b) the survival and success rates of implants placed in the reconstructed or distracted areas.

MATERIAL AND METHODS

In a 2-year period (2001-2002), 17 patients presenting with vertically atrophied partially edentulous mandibles requiring implant-supported prosthetic rehabilitation, were included in this study. Patients were randomly assigned to two groups. Eight patients (group 1) were treated with ABG harvested from the mandibular ramus, while nine patients (group 2) were treated by means of DO. In group 1, patients received implants 4-5 months after the reconstructive procedure, while in group 2 implants were placed at the time of distraction device removal (approximately 3 months after the completion of distraction). A total of 19 endosseous implants were placed in group 1, and 21 implants were placed in group 2 patients. For both groups, after an additional 3-5-month period, prosthetic rehabilitation was started.

RESULTS

Bone resorption before implant placement was significantly higher in group 1 (P=0.01), while no statistically significant differences were found between the two groups as far as survival and success rates of implants and peri-implant bone resorption after the start of prosthetic loading were concerned.

CONCLUSION

The results suggested that: (a) both techniques may effectively improve the deficit of vertically resorbed edentulous ridges; (b) survival and success rates of implants placed in the reconstructed/distracted areas are consistent with those of implants placed in native bone.

Le Fort I osteotomy with interpositional bone grafts and delayed oral implants for the rehabilitation of extremely atrophied maxillae: a 1?9-year clinical follow-up study on humans

AIM

The purpose of this clinical follow-up study was to report the clinical outcome of osseointegrated implants placed in extremely atrophied edentulous maxillae after Le Fort I osteotomy and interpositional autogenous iliac bone grafts.

PATIENTS AND METHODS

In a 10-year period (1995-2004), 39 patients, 18 males and 21 females, aged from 32 to 76 years, presenting with severely atrophied edentulous maxillae were treated with Le Fort I osteotomy and interpositional iliac bone grafts. Four to 8 months after the reconstructive procedure, 281 osseointegrated implants were placed in the reconstructed maxillae. Four to 8 months afterwards, abutments were connected and the prosthetic rehabilitation started. The mean follow-up period of implants after the start of prosthetic loading was 45.9 months (range: 12-108 months).

RESULTS

The reconstructive procedure was successful in 38 of 39 patients. In one patient, partial loss of the inlay graft occurred before implant placement. Six patients (42 implants) dropped out of the study. Fifteen implants were removed during the follow-up period, due to loss of integration. Thirty-two implants, although integrated, presented with peri-implant bone-level changes higher than those proposed for successful implants. Cumulative survival and success rates of implants were 94.5% and 82.9%, respectively.

CONCLUSION

Results from this study showed that Le Fort I osteotomy with interpositional bone grafts followed by delayed implant placement is an acceptable means to rehabilitate edentulous patients affected by extremely atrophied edentulous maxillae. Survival rates of implants are consistent with those related to implants placed in native, non-reconstructed bone. Conversely, the success rate of implants resulted to be lower as compared with those obtained for implants placed in native bone.

Immediate loading of dental implants placed in severely resorbed edentulous mandibles reconstructed with autogenous calvarial grafts

OBJECTIVE

The aim of this prospective study was to present the clinical outcome of immediately loaded dental implants placed in edentulous, severely atrophied mandibles, after reconstruction with autogenous multilayered calvarial grafts.

MATERIALS AND METHODS

Six patients, two males and four females, aged 40-67 years (mean: 56 years) presenting with severely atrophied edentulous mandibles (Cawood and Howell class VI), were reconstructed with multilayered calvarial bone grafts placed in the intraforaminal area of the mandible. Five to 8 months afterwards, 23 dental implants were placed in the reconstructed areas (three to four implants per patient) and immediately loaded with implant-supported overdentures. Patients were followed with clinical and radiographic controls annually.

RESULTS

Recovery after the reconstruction was uneventful in all patients. All 23 implants were osseointegrated 1-3 years after the start of immediate loading. The survival and success rates of implants were 100% and 95.7%, respectively.

CONCLUSION

Results from this study showed that immediate loading of dental implants placed in severely atrophied edentulous mandibles reconstructed with calvarial bone grafts is a predictable procedure, which permits a successful dental rehabilitation with a shortening of treatment times.

Comparison of clinical, radiographic and immunological parameters of teeth and different dental implant platforms

A comparison between host response in teeth and dental implants was not made. Likewise, the association between host response and periodontal parameters has never been explored. The purpose of this study was to compare periodontal health around natural teeth and dental implants with different restorative platforms. Twenty-seven partially edentulous patients with dental implants, either external hex butt joint (n=28) or tapered Morse (n=45), were included in this study. Implants were in function for 1-6 years (mean 2.9). Plaque index (PI), gingival index (GI), probing depth (PD); and clinical attachment level (CAL), were recorded at final examination; alveolar bone loss (ABL) was measured at baseline and final examination using panoramic radiographs. Gingival crevicular fluid samples were obtained from the Ramfjord index teeth and all implants and assayed using enzyme-linked immunosorbent assay for prostaglandin E(2) (PGE(2)), interleukin-1 (IL-1) and tumour necrosis factor alpha (TNFalpha). Differences between teeth and implants and between the two implant platforms were compared using Student's t-test. Correlations between cytokines, ABL and clinical parameters were analyzed using Pearson's co-efficient test. PI and GI were significantly higher in teeth than dental implants (1.2+/-0.5 vs. 0.8+/-0.5, P=0.0018; 1.2+/-0.3 vs. 1.1+/-0.3, P=0.048). Conversely, PD was deeper in implants (2.66+/-0.6 vs. 3.66+/-0.9, P=0.001). GI and PD around teeth and implants were positively associated (R=0.561, P=0.0023; R=0.39, P=0.0452). Greater ABL was observed around dental implants (1.62+/-2.2 mm) compared with teeth (0.49+/-0.3 mm). A positive correlation was found between both IL-1 (R=0.73, P=0.0064; R=0.52, P=0.0081) and TNFalpha (R=0.64, P=0.0246; R=0.46, P=0.091) and ABL in teeth and implants. Both implant platforms were similar clinically and radiographically; however, TNFalpha (2.49+/-0.3 vs. 4.79+/-0.5, P=0.004) and IL-1 (24.52+/-7.3 vs. 45.41+/-9.9, P=0.095) were higher for the non-submerged implants. In conclusion, IL-1 and TNFalpha are sensitive markers of ABL around teeth and implants. The two dental implant platforms showed a similar clinical and radiographic response; however, the greater host response in the non-submerged implants might suggest future bone loss.

Outcome of Oral Implant Treatment in Partially Edentulous Jaws Followed 20 Years in Clinical Function

BACKGROUND

Most long-term follow-up studies of implants in partially edentulous jaws present their outcomes as mean values of implant survival and follow-up time, and few address the fate of the remaining teeth.

PURPOSE

The aim of this study was to investigate the results of oral implant treatment in partially edentulous jaws after 20 years, and simultaneously to assess what happens to teeth present at the time of implant placement.

MATERIALS AND METHODS

Seventeen partially edentulous patients, of 27 originally treated individuals, were retrospectively reviewed after receiving implants from 1983 to 1985. The parameters studied were implant survival, prosthesis stability, marginal bone loss at teeth and implants, treatment complications, need for dental treatment, and patient's satisfaction with the outcome.

RESULTS

The cumulative survival rate was 91%, when all 27 patients were assessed, that is, including the 10 dropouts. Of the 69 inserted and followed implants (Brånemark system; Nobel Biocare AB, Göteborg, Sweden), six failed (8.7%) during the 20-year period, four during the first decade, and the remaining two during the second. A majority (n=4) of the losses were due to implant fractures, two after 8 years, and two after 17 years. In all, 10 of the original fixed bridges being followed (n=24) remained in function during the entire investigation period, whereas 12 were exchanged for new constructions after an average of 7 years. The mean marginal bone loss at teeth was 0.7 mm, and at implants it was 1.0 mm. The major complication observed during the second decade was veneer material fractures, which occurred 14 times in six patients. Component loosening and abutment- and bridge-locking screw fractures were the second most common problems seen, indicating material/component fatigue. Most patients were satisfied with their treatment and many mentioned that they did not think of the constructions as anything but a part of their own body.

CONCLUSION

Over the decades, treatment of partially edentulous jaws with turned titanium implants seems to function well and to provide patients with good support for fixed short-span bridge constructions.

Augmentation procedures for the rehabilitation of deficient edentulous ridges with oral implants

OBJECTIVES

To analyze publications related to augmentation procedures and to evaluate the success of different surgical techniques for ridge reconstruction and the survival/success rates of implants placed in the augmented areas.

MATERIAL AND METHODS

Clinical investigations published in English involving at least 5 patients and with a minimum follow-up of 6 months were included. The following procedures were considered: a) Guided bone regeneration (GBR); 2) Onlay bone grafts; 3) Inlay grafts; 4) Bone splitting for ridge expansion (RE); 5) Distraction osteogenesis (DO); and 6) Revascularized flaps. Success rates of augmentation procedures and related morbidity, as well as survival and success rates of implants placed in the augmented sites were analyzed.

RESULTS

Success rates of surgical procedures ranged from 60% to 100% for GBR, from 92% to 100% for onlay bone grafts, from 98% to 100% for ridge expansion techniques, from 96,7% to 100% for DO, and was 87.5% for revascularized flaps, whereas survival rates of implants ranged from 92% to 100% for GBR, from 60% to 100% for onlay bone grafts, from 91% to 97.3% for RE, from 90.4% to 100% for DO, and, finally, was 88.2% for revascularized flaps.

CONCLUSION

On the basis of available data it was shown that it was difficult to demonstrate that a particular surgical procedure offered better outcome as compared to another. The main limit encountered in this review has been the overall poor methodological quality of the published articles. Therefore larger well-designed long term trials are needed.

Outcome of implant therapy in patients with previous tooth loss due to periodontitis

BACKGROUND

It is frequently debated whether implant treatment in individuals with previous tooth loss due to periodontitis is characterized by an increased incidence of implant loss and peri-implantitis.

OBJECTIVE

The objective of the present systematic review was to assess whether individuals with previous tooth loss due to periodontitis have an increased risk of loss of suprastructures, loss of implants, peri-implantitis, and peri-implant marginal bone loss as compared with individuals with previous tooth loss due to reasons other than periodontitis.

SEARCH STRATEGY

Studies considered for inclusion were searched in MEDLINE (PubMed) and relevant journals were hand searched. Moreover, reference lists of articles selected for full-text screening as well as previously published reviews relevant for the present systematic review were searched. The search was performed by one reviewer and was restricted to human studies published from January 1, 1980 to January 1, 2006. No language restrictions were applied.

SELECTION CRITERIA

Prospective and retrospective cohort studies with at least a 5-year follow-up comparing the outcome of implant treatment in individuals with periodontitis-associated and non-periodontitis-associated tooth loss, respectively, were included. The outcome measures were survival of suprastructures, survival of implants, occurrence of peri-implantitis, and peri-implant marginal bone loss. The 5- and 10-year time points were evaluated.

DATA COLLECTION AND ANALYSIS

Screening of eligible studies, methodological quality assessment, and data extraction were conducted in duplicate and independently by two of the authors. The authors were contacted for missing information. Results were expressed as random effect models using weighted mean differences for continuous outcomes and relative risk for dichotomous outcomes with 95% confidence intervals (CIs).

MAIN RESULTS

Two studies with a 5- and 10-year follow-up, respectively, were identified including a total of 33 patients with tooth loss due to periodontitis and 70 patients with non-periodontitis-associated tooth loss. There was no significant difference in the survival of the suprastructures after 5 years. Furthermore, there were no significant differences in the survival of the implants after 5 and 10 years. However, there were significantly more patients affected by peri-implantitis in the group with periodontitis-associated tooth loss during the 10-year follow-up period, risk ratio (RR) 9 (95% CI 3.94-20.57). Moreover, significantly increased peri-implant marginal bone loss was observed in patients with periodontitis-associated tooth loss after 5 years, mean difference 0.5 mm (95% CI 0.06-0.94).

CONCLUSIONS

The survival of the suprastructures and the implants was not significantly different in individuals with periodontitis-associated and non-periodontitis-associated tooth loss. However, significantly increased incidence of peri-implantitis and significantly increased peri-implant marginal bone loss were revealed in individuals with periodontitis-associated tooth loss. The small sample size and the methodological quality assessment of the two studies suggest that the results should be interpreted with caution. Consequently, further long-term studies focusing particularly on the outcome of implant treatment in young adults with aggressive periodontitis are needed before final conclusions can be drawn about the outcome of implant treatment in patients with a history of periodontitis.

Quality and quantity of bone following alveolar distraction osteogenesis in the human mandible

PURPOSE

The purpose of this prospective study on humans were to evaluate (a) the clinical outcome of alveolar distraction osteogenesis for the correction of vertically deficient edentulous mandibular ridges, (b) the clinical outcome of dental implants placed in the distracted areas, and (c) the quality and quantity of the bone that had formed in the distraction gap.

MATERIAL AND METHODS

Seven patients presenting vertically deficient edentulous ridges were treated by means of distraction osteogenesis with an intraoral alveolar distractor. Approximately 3 months after consolidation of the distracted segments, 20 ITI solid screw SLA implants were placed in the distracted areas. Three to 4 months later, abutments were connected and prosthetic loading of the implants started. During implant site preparation, bone biopsies were taken at the implant sites with trephine burrs for histologic and histometric analyses.

RESULTS

The mean follow-up after the initial prosthetic loading was 18 months (range 12-24 months). The mean bone gain obtained at the end of distraction was 7 mm (range 5-9 mm). The cumulative success rate of implants 2 years after the onset of prosthetic loading was 95%, whereas the survival rate of implants was 100%. The newly formed bone consisted of woven bone reinforced by parallel-fibered bone with bone marrow spaces between the bone trabeculae. The bone area fraction in the distraction region ranged from 21.6% to 57.8% (38.5+/-11.7%).

DISCUSSION AND CONCLUSIONS

Results from this study showed that (a) distraction osteogenesis is a reliable technique for the correction of vertically deficient edentulous ridges, (b) the regenerated bone withstood the functional demands of implant loading, (c) survival and success rates of implants placed in the distracted areas were consistent with those of implants placed in native bone, and (d) there is sufficient bone volume and maturity in the distracted region for primary stability of the implant.

Feasibility and Influence of the Microgap of Two Implants Placed in a Non-Submerged Procedure: A Five-Year Follow-Up Clinical Trial

BACKGROUND

The aim of this study was to evaluate the feasibility of using a two-piece implant system in a non-submerged procedure and to study the impact of the microgap between the implant and abutment.

METHODS

Sixty edentulous patients (Cawood Class V-VI) participated in this study. After randomization, 20 patients received two two-piece implants placed in a non-submerged procedure, 20 patients received two two-piece implants placed in the traditional submerged procedure, and 20 patients were treated with two one-piece dental implants placed in the traditional non-submerged procedure. The implants were placed in the mandible for overdenture treatment. A standardized clinical evaluation was performed and radiographs were taken immediately after denture insertion and yearly up to 5 years. Peri-implant samples were collected 12, 36, and 60 months after loading with sterile paper points and analyzed for the presence of putative periodontal pathogens using culture techniques.

RESULTS

One two-piece implant of the non-submerged group and one two-piece implant of the submerged group were lost after 6 and 12 months, respectively. After 5 years of functioning, no significant clinical, radiological, or microbiological differences were found between the three groups. No association was found between the level of the microgap and the amount of bone loss.

CONCLUSIONS

The results of this study indicate that dental implants designed for a submerged implantation procedure can also be used in a non-submerged procedure and may be as predictable as when used in a submerged procedure or as one-piece implants. The microgap at the crestal level in two-piece implants does not appear to have an adverse effect on the amount of peri-implant bone loss.

Dental implants placed in expanded narrow edentulous ridges with the Extension CrestR device. A 1-3-year multicenter follow-up study

OBJECTIVE

This study has been designed to evaluate the capability of a new surgical device (Extension Crest) to widen narrow edentulous alveolar ridges and to allow a correct placement of endosseous implants in horizontally atrophied sites.

MATERIAL AND METHODS

Forty-five patients, 20 males and 25 females, aged 20-66 years, affected by edentulism associated to horizontal resorption of the ridges, were treated by means of a sagittal osteotomy and expansion of the ridge with a new surgical device (Extension Crest) to obtain a wider bony base for ideal implant placement. In the same procedure in 33 patients, and 1 week afterwards in 12 patients, 110 endosseous titanium implants (ITI TE) were placed. Three to four months later, the patients were rehabilitated with implant-supported prostheses.

RESULTS

The success rate of the expansion technique was 97.8%. A total of 110 implants were inserted in the expanded ridges. The mean follow-up after the start of prosthetic loading was 20.4 months. Three implants were removed before the start of prosthetic loading, because of non-integration, while no other implants failed after the completion of the prosthetic rehabilitation. Three implants, although integrated and in function, did not fulfill success criteria: cumulative success and survival rates at the end of the observation period were 95.4% and 97.3%, respectively.

CONCLUSION

Within the limits of this study, this technique appeared to be reliable and simple, with reduction of morbidity and times of dental rehabilitation as compared with other techniques such as autogenous bone grafts and guided bone regeneration. Survival and success rates of implants placed in the treated areas are consistent with those placed in native bone.

Comparison of bacterial plaque samples from titanium implant and tooth surfaces by different methods

Studies have shown similarities in the microflora between titanium implants or tooth sites when samples are taken by gingival crevicular fluid (GCF) sampling methods. The purpose of the present study was to study the microflora from curette and GCF samples using the checkerboard DNA-DNA hybridization method to assess the microflora of patients who had at least one oral osseo-integrated implant and who were otherwise dentate. Plaque samples were taken from tooth/implant surfaces and from sulcular gingival surfaces with curettes, and from gingival fluid using filter papers. A total of 28 subjects (11 females) were enrolled in the study. The mean age of the subjects was 64.1 years (SD+/-4.7). On average, the implants studied had been in function for 3.7 years (SD+/-2.9). The proportion of Streptococcus oralis (P<0.02) and Fusobacterium periodonticum (P<0.02) was significantly higher at tooth sites (curette samples). The GCF samples yielded higher proportions for 28/40 species studies (P-values varying between 0.05 and 0.001). The proportions of Tannerella forsythia (T. forsythensis), and Treponema denticola were both higher in GCF samples (P<0.02 and P<0.05, respectively) than in curette samples (implant sites). The microbial composition in gingival fluid from samples taken at implant sites differed partly from that of curette samples taken from implant surfaces or from sulcular soft tissues, providing higher counts for most bacteria studied at implant surfaces, but with the exception of Porphyromonas gingivalis. A combination of GCF and curette sampling methods might be the most representative sample method.

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.

Subgingival microbiota in peri-implant mucosa lesions and adjacent teeth in partially edentulous patients

BACKGROUND

Osseointegrated dental implants have been shown to be a predictable approach to provide the adequate support for the replacement of missing teeth. It has been observed that implants showing signs of peri-implantitis contain subgingival microbiota similar to that around natural teeth with periodontal disease. This study identified the subgingival microbiota around implants with peri-implant lesions and natural teeth in partially edentulous patients.

METHODS

Clinical and radiographic parameters were recorded and microbial samples taken from 16 implants with signs of pocketing, 12 neighboring and 11 non-neighboring teeth to the affected implants in 11 patients and 15 stable implants in eight patients (controls). Samples were cultured using techniques for Enterobacteriaceae spp and facultative/anaerobic periodontal pathogens. Statistical analysis included Friedman test to establish differences between the subgingival microbiota cultured from implants and teeth and two-tailed Mann Whitney test and chi square to find differences in two separate samples (P < or = 0.05).

RESULTS

There were statistical differences between the subgingival microbiota in peri-implant lesions and stable implants for Gram-negative enteric rods (P <0.05). P. gingivalis (1.42%) was detected in peri-implant lesions but not in stable implants. A significant correlation between the subgingival microbiota from implants and neighboring teeth for Gram-negative enteric rods (P = 0.023) and implants and non-neighboring teeth for P. gingivalis (P = 0.042) was found. The frequency detection of Gram-negative enteric rods (75%) and P. intermedia/nigrescens (25%) was higher in peri-implant lesions (P <0.05).

CONCLUSIONS

The subgingival microbiota in peri-implant lesions showed high levels of periodontopathic bacteria and superinfecting bacteria compared to healthy stable implants. The role of superinfecting bacteria in the pathogenesis of peri-implant lesions needs further investigation.

Early colonization of non-submerged dental implants in patients with a history of advanced aggressive periodontitis

The aim of the study was to evaluate the early colonization of non-submerged implants over a 6-month period in partially edentulous patients treated for advanced aggressive periodontal disease. In 22 patients treated for advanced aggressive periodontitis and in a supportive maintenance program for a period between 12 and 240 months at implant surgery, a total of 68 non-submerged dental implants were installed. Patients had a plaque score below 20%, and less than 20% of the pockets around the teeth were bleeding on probing (BOP). Using DNA-probes (micro-IDent), the presence and concentration of five periodontal pathogens (Actinobacillus actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), Prevotella intermedia (Pi), Tannerella forsythensis (Tf) and Treponema denticola (Td)) were determined in the five deepest pockets of the rest dentition pre-operatively and after 6 months as well as five places around each implant 10 days, 1 month, 3 months and 6 months after surgery. In each patient, a test to determine the genotype interleukin-1 (IL-1) was performed (PST - micro-IDent). After 6 months, no difference in microbial composition as compared with baseline was found around the teeth in five patients, in 12 minute differences and in five patients important differences were observed. Ten days after surgery, three patients had a complete similar bacterial composition between teeth and implants. In 14 patients, the composition was fairly similar, while large differences in composition and concentration occurred in five patients. This microbiota around the implants remained almost unchanged over a 6-month period and did not hamper the clinical and radiographic osseointegration and did not lead to peri-implantitis, mucositis or initiation of bone destruction.

Comparisons of bacterial patterns present at implant and tooth sites in subjects on supportive periodontal therapy

OBJECTIVE

(I) To compare the oral microflora at implant and tooth sites in subjects participating in a periodontal recall program, (II) to test whether the microflora at implant and tooth sites differ as an effect of gingival bleeding (bleeding on probing (BOP)), or pocket probing depth (PPD), and (III) to test whether smoking and gender had an impact on the microflora.

MATERIAL AND METHODS

Data were collected from 127 implants and all teeth in 56 subjects. Microbiological data were identified by the DNA-DNA checkerboard hybridization.

RESULTS

PPD> or =4 mm were found in 16.9% of tooth, and at 26.6% of implant sites (P<0.01). Tooth sites with PPD> or =4 mm had a 3.1-fold higher bacterial load than implant sites (mean difference: 66%, 95% confidence interval (CI): 40.7-91.3, P<0.001). No differences were found for the red, orange, green, and yellow complexes. A higher total bacterial load was found at implant sites with PPD> or =4 mm (mean difference 35.7 x 10(5), 95% CI: 5.2 (10(5)) to 66.1 (10(5)), P<0.02 with equal variance not assumed). At implant sites, BOP had no impact on bacterial load but influenced the load at tooth sites (P<0.01).

CONCLUSION

BOP, and smoking had no impact on bacteria at implant sites but influenced the bacterial load at tooth sites. Tooth sites harbored more bacteria than implant sites with comparable PPD. The 4 mm PPD cutoff level influenced the distribution and amounts of bacterial loads. The subject factor is explanatory to bacterial load at both tooth and implant sites.

Dynamics of initial subgingival colonization of ‘pristine’ peri-implant pockets

BACKGROUND

Periodontitis and peri-implantitis are linked to the presence of several key pathogens. The treatment of these infectious processes therefore involves the reduction/eradication of bacteria associated with periodontitis.

METHODS

This prospective, split-mouth, single-blind study followed the colonization of 'pristine' sulci created in 42 partially edentulous patients during implant surgery (e.g. abutment connection). The hypothesis was that the composition of the maturing subgingival plaque in these 'fresh' peri-implant pockets would soon (within 2 weeks) be comparable to the subgingival microbiota of teeth with similar clinical parameters (reference sites), including the presence of bacteria associated with periodontitis. Per patient, four subgingival plaque samples were taken from shallow and medium pockets around implants (test sites), and teeth within the same quadrant (undisturbed microbiota as control sites), 1, 2, 4, 13, 26 and 78 weeks after abutment connection, respectively. The samples were analysed by either checkerboard DNA-DNA hybridization, or cultural techniques, or real-time polymerase chain reaction (PCR) for intra-subject comparisons (teeth vs. implant, for comparable probing depths).

RESULTS

Checkerboard DNA-DNA hybridization and real-time PCR revealed a complex microbiota (including several pathogenic species) in the peri-implant pockets within 2 weeks after abutment connection. After 7 days, the detection frequency for most species (including the bacteria associated with periodontitis) was already nearly identical in samples from the fresh peri-implant pockets (5% and 20% of the microbiota belonging to red and orange complex, respectively) when compared with samples from the reference teeth. Afterwards (e.g. between weeks 2 and 13), the number of bacteria in peri-implant pockets only slightly increased (+/-0.1 log value), with minor changes in the relative proportions of bacteria associated with periodontitis (8% and 33% of the microbiota belonging to red and orange complex, respectively). Although small differences were seen between teeth and implants at week 2 with cultural techniques, a striking similarity in subgingival microbiota was found with this technique from month 3 on, with nearly identical detection frequencies for bacteria associated with periodontitis for both abutment types.

CONCLUSIONS

This study indicates that the initial colonization of peri-implant pockets with bacteria associated with periodontitis occurs within 2 weeks.

Characterization of Actinomyces species isolated from failed dental implant fixtures

In the oral cavity, Actinomyces form a fundamental component of the indigenous microflora, being among initial colonizers in polymicrobial biofilms. However, some differences may exist between different species in terms of their attachment not only to teeth but also to biomaterials. In this study we investigated the distribution of Actinomyces in 33 dental implant fixtures explanted from 17 patients. The identification was based on comprehensive biochemical testing and gas-liquid chromatography and when needed, 16S rRNA sequencing. Actinomyces was the most prevalent bacterial genus in these failed implants, colonizing 31/33 (94%) of the fixtures. Proportions of Actinomyces growth of the total bacterial growth in the Actinomyces-positive fixtures varied from 0.01% up to 75%. A. odontolyticus was the most common Actinomyces finding, present in 26/31 (84%) Actinomyces-positive fixtures. Actinomyces naeslundii and A. viscosus were both detected in 10/31 (32%) and A. israelii in 7/31 (23%) fixtures. Other Actinomyces species, including A. georgiae, A. gerencseriae and A. graevenitzii, were detected less frequently. Our results suggest that Actinomyces species are frequent colonizers on failed implant surfaces, where A. odontolyticus was the far most prominent Actinomyces species.

Implant therapy in partially edentulous, periodontally compromised patients: a review

AIM

The purpose of the present study was to perform a review using a systematic approach to evaluate the long-term (>/=5 years) success of implants placed in partially edentulous patients with a history of periodontitis as evidenced by loss of supporting bone and implant loss.

MATERIAL & METHODS

An electronic search of the National Library of Medicine, Washington DC (Medline-PubMed) was performed using specific search terms to identify studies assessing, in periodontitis patients, the success of implants with regard to bone level outcomes. Search was performed on abstracts registered up to October 2003.

RESULTS

The searches identified 877 abstracts. Titles and abstracts were independently screened by two reviewers (G.A.W. & K.M.B.) to identify publications that met the inclusion criteria. Review of these abstracts resulted in 13 publications for detailed review. These papers were reviewed by the three authors. Finally four papers which met the criteria of eligibility were independently selected by the three reviewers.

CONCLUSION

Based on the limited data, it seems justified to conclude that the outcome of implant therapy in periodontitis patients may be different compared to individuals without such a history as evidenced by loss of supporting bone and implant loss.

Analysis of the presence of pathogens which predict the risk of disease at peri-implant sites through polymerase chain reaction (PCR)

The presence of DNA of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, and Prevotella intermedia in the peri-implant sulcus samples of 19 partially edentulous patients was analyzed by polymerase chain reaction (PCR) and related to the depth of the peri-implant sulcus, bleeding on probing, and probable risk of disease. Ten of those patients presented a history of periodontal disease and nine of those did not. The DNA amplification of these pathogens was observed in seven samples, of which four were from patients without history of periodontal disease. The results suggest that even when significant inflammatory signs are absent the qualitative detection may indicate risk of peri-implantitis, requiring more strict postoperative control.

Implant Survival in Periodontally Compromised Patients

BACKGROUND

Relatively little is known on the long-term prognosis of implants inserted in partially edentulous, periodontally compromised patients.

METHODS

A total of 258 conventional implants, 57 two-stage and 201 one-stage implants, which were inserted in 32 and 108 patients, respectively, between June 1988 and June 2002 were followed with respect to their survival, as well as the periodontal parameters bone loss, probing depth, and bleeding on probing. All patients were periodontally compromised who had undergone periodontal surgery and were considered able to maintain a high standard of oral hygiene.

RESULTS

The 5-year survival rates were 97% and 94%, respectively, for the two- and the one-stage implants. The 10-year survival rate remained high at 97% for the two-stage implants, but had dropped to 78% for the one-stage implants. Smoking, short implant length, and insertion during the later period (1995-2002) were found to be associated with an increased failure rate.

CONCLUSIONS

Implants placed in patients with a history of periodontitis have a 5-year survival similar to that observed for implants installed in non-diseased persons. Although the 10-year survival of the one-stage implants was somewhat lower than has been observed for non-diseased patients, implant placement remains a good treatment alternative also for periodontally compromised patients.

Alveolar distraction osteogenesis vs. vertical guided bone regeneration for the correction of vertically deficient edentulous ridges: A 1-3-year prospective study on humans

The purpose of this prospective study was to compare vertical guided bone regeneration (GBR) and vertical distraction osteogenesis (DO) for their ability in correcting vertically deficient alveolar ridges and their ability in maintaining over time the vertical bone gain obtained before and after implant placement. Eleven patients (group 1) were treated by means of vertical GBR with autogenous bone and e-PTFE membranes, while 10 patients (group 2) were treated by means of DO. In group 1, six patients received implants at the time of GBR (subgroup 1A), while five patients had implants placed at the time of membrane removal (subgroup 1B). In group 2, implants were placed at the time of distraction device removal. A total of 25 implants were placed in group 1 and 34 implants were placed in group 2 patients. Three to 5 months after implant placement, patients were rehabilitated with implant-borne dental prostheses. The following parameters were evaluated: (a) bone resorption of the regenerated ridges before and after implant placement; (b) peri-implant clinical parameters 1, 2, and 3 years after prosthetic loading of implants; (c) survival and success rates of implants. Bone resorption values before and after implant placement were significantly higher in group 1. The results suggested that both techniques may improve the deficit of vertically resorbed edentulous ridges, although distraction osteogenesis seems to be more predictable as far as the long-term prognosis of vertical bone gain is concerned. Implant survival rates as well as peri-implant clinical parameters do not differ significantly between the two groups, whereas the success rate of implants placed in group 2 patients was higher than that obtained in group 1 patients.

Microbiologic Diagnostics at Titanium Implants

BACKGROUND

The microbiota found at periimplant lesions have been shown to contain putative periodontal pathogens as well as opportunistic species such as Staphylococcus spp, enterics, and Candida spp. Therefore, a microbiologic diagnosis may be of value as guidance before treatment of such lesions.

PURPOSE

The aim of this study was to evaluate the prevalence of some putative pathogens associated with long-term followed-up cases using two different microbiologic procedures.

MATERIALS AND METHODS

Fifteen subjects contributed with plaque samples from teeth and implants; these were analyzed with respect to 18 putative periimplant pathogens using cultural methods and a deoxyribonucleic acid DNA-DNA hybridization technique.

RESULTS

The number of individuals positive for the analyzed pathogens was similar in samples taken from teeth and implants when analyzed with the DNA-DNA hybridization technique. When comparing detection frequency by culture procedure and by "checkerboard" technique at implants, the number of individuals positive for these species was lower with the traditional culture technique than with the checkerboard analyses. Using a higher cutoff point (> or = 4) with the checkerboard technique, the number of positive individuals was generally lower than that found with the culture technique. When comparing the techniques on an implant site level, the prevalence obtained by culture was lower for all analyzed species. If the specific species were present in the samples analyzed by the checkerboard technique, they were present only in every second sample analyzed with the culture technique. The high specificity values showed that if the checkerboard technique did not detect any Porphyromonas gingivalis, Prevotella intermedia, Actinobacillus actinomycetemcomitans, or Fusobacterium nucleatum, the bacteria were also undetectable by the culture technique. The two methods therefore did not overlap but did supplement each other.

CONCLUSIONS

Based on the current results it is recommended that the technique used when analyzing microbiota around titanium implants should be a combination of the two protocols mentioned as they seem to give the most comprehensive outcome when used together.

Five-Year Clinical, Microbiological, and Radiological Outcome Following Treatment of Peri-Implantitis in Man

BACKGROUND

The aim of this study was to evaluate the long-term outcome of a combined surgical and antimicrobial treatment of peri-implantitis lesions in humans.

METHODS

Nine partially dentate individuals with titanium implants demonstrating a marginal bone loss of > or = three threads as compared to baseline measurements made from 1-year intra-oral radiographs, bleeding on probing, and/or suppuration from the peri-implant sulci were included in the study. In each individual, subgingival bacterial samples were obtained and subjected to microbiological analysis by culture. Surgical exposure of the lesions and cleaning of the implants using hydrogen peroxide were performed. The patients were given systemic antibiotics according to a susceptibility test of target bacteria. The treatment was evaluated clinically, microbiologically, and radiograpically at 6 months, 1 year, and 5 years.

RESULTS

Seven out of 26 implants with peri-implantitis at baseline were lost during the 5-year follow-up period despite a significant reduction in the presence of plaque and gingival bleeding. Four implants continued to lose bone, 9 had an unchanged bone level, and 6 gained bone. Five of the patients were treated with antibiotics directed against putative periodontopathogens, i.e., A. actinomycetemcomitans, P. intermedia, or P. gingivalis; three patients were treated for presence of enterics (E. coli and E. cloace); and, in one patient, treatment was directed against S. aureus.

CONCLUSIONS

Despite treatment and retreatment, seven implants were lost. However, the applied surgical and antimicrobial treatment strategy for advanced peri-implantitis lesions was successful in 58% of the implants treated during the 5-year follow-up period. Smoking seemed to be a negative risk factor for treatment success.