Francesco Zuffetti

Immediate occlusal loading and tilted implants for the rehabilitation of the atrophic edentulous maxilla: 1-year interim results of a multicenter prospective study

OBJECTIVES The aims of this prospective study were to assess the treatment outcome of immediately loaded full-arch fixed bridges anchored to both tilted and axially placed implants for the rehabilitation of fully edentulous maxillae and to compare the outcome of axial vs. tilted implants. MATERIAL AND METHODS Forty-one patients with edentulous maxillae were included in the study. Each patient received a full-arch fixed bridge supported by four axial implants and two distal tilted implants. Loading was applied within 48 h from surgery. Patients were scheduled for follow-up at 6 months, 1 year and annually up to 5 years. Radiographic evaluation of marginal bone-level change was performed at 1 year. RESULTS One patient died 4 months after surgery. Thirty patients were followed for a minimum of 1 year (range 3-42 months, mean 22.1 months). Three failures were recorded at 1-year follow-up (two axial implants and one tilted). Two more implants (one tilted and one axially placed) were lost within 18 months of loading. The 1-year implant survival rate was 98.8% for both axial and tilted implants. Prosthesis success rate was 100% at 1 year. Marginal bone loss around axial and tilted implants at 12-month evaluation was similar, being, respectively, 0.9+/-0.4 (standard deviation) mm and 0.8+/-0.5 mm. CONCLUSIONS The present preliminary data suggest that immediate loading associated with tilted implants could be considered to be a viable treatment modality for the atrophic maxilla and that there does not seem to be a different clinical outcome between tilted and axial implants.

Immediate non-occlusal vs. early loading of dental implants in partially edentulous patients: a multicentre randomized clinical trial. Peri-implant bone and soft-tissue levels.

OBJECTIVES To compare peri-implant bone and soft-tissue levels of immediately non-occlusally loaded vs. non-submerged early loaded implants in partially edentulous patients up to 14 months after placement. MATERIAL AND METHODS Fifty-two patients were randomized in five Italian private practices: 25 in the immediately loaded group and 27 in the early loaded group. To be immediately loaded, single implants had to be inserted with a torque of > or = 30 N cm, and splinted implants with a torque of > or = 20 N cm. Immediately loaded implants were provided with non-occluding temporary restorations within 48 h. After 2 months, the provisional restorations were placed in full occlusion. Implants were early loaded after 2 months. Final restorations were provided 8 months after placement. Blinded assessors evaluated peri-implant bone and soft-tissue levels. RESULTS Fifty-two implants were immediately loaded and 52 were early loaded. No drop-out occurred. One single immediately loaded implant failed 2 months after placement. Both groups gradually lost peri-implant bone in a highly statistically significant manner at 2, 8, and 14 months. After 14 months, patients of both groups lost an average of 1.1 mm of peri-implant bone. There were no statistically significant differences between the two loading strategies for peri-implant bone and soft-tissue level changes (P > 0.05). After 14 months, the position of the soft tissues did not change significantly from baseline (delivery of the final restorations 8 months after placement). CONCLUSIONS There were no statistically or clinically significant differences between immediate and early loading of dental implants with regard to peri-implant bone and soft-tissue levels as evaluated in the present study.

Prevention and treatment of postoperative infections after sinus elevation surgery: clinical consensus and recommendations.

Introduction. Maxillary sinus surgery is a reliable and predictable treatment option for the prosthetic rehabilitation of the atrophic maxilla. Nevertheless, these interventions are not riskless of postoperative complications with respect to implant positioning in pristine bone. Aim. The aim of this paper is to report the results of a clinical consensus of experts (periodontists, implantologists, maxillofacial surgeons, ENT, and microbiology specialists) on several clinical questions and to give clinical recommendations on how to prevent, diagnose, and treat postoperative infections. Materials and Methods. A panel of experts in different fields of dentistry and medicine, after having reviewed the available literature on the topic and taking into account their long-standing clinical experience, gave their response to a series of clinical questions and reached a consensus. Results and Conclusion. The incidence of postop infections is relatively low (2%–5.6%). A multidisciplinary approach is advisable. A list of clinical recommendation are given.

Implant–Buccal Plate Distance as Diagnostic Parameter: A Prospective Cohort Study on Implant Placement in Fresh Extraction Sockets

BACKGROUND The aim of this study is to investigate contour changes around immediate implants in fresh extraction sockets when different grafting procedures are performed, based on the distance between the external implant collar and the bony surface on the buccal plate (I-BP). A secondary aim is to assess the esthetic outcome via the implant esthetic score (IAS). METHODS This prospective cohort study was performed in three centers. Suitable patients to undergo implant placement in fresh extraction sockets were selected. Periodontal biotype, horizontal and vertical peri-implant bone defects, and dehiscences were assessed. Depending on I-BP, two types of grafting procedures were performed. In group A (I-BP <4 mm), only the peri-implant gap was grafted during the surgical phase (internal grafting [IG]), whereas group B (I-BP ≥ 4 mm) received both internal and external grafting (IEG). Master casts of the sites, made before implant placement and after 1 year of loading, were optically scanned. A computerized analysis of the contour changes at the involved sites was performed by superimposing the scanned models. RESULTS A total of 20 patients (eight males and 12 females) were recruited, and 20 non-submerged implants were placed in fresh extraction sockets. No implant failed during the observation period. The mean follow-up was 25 months (range: 12 to 37 months). After 1 year of loading, group A showed a slight decrease in mean buccal volume, whereas group B had an increase in volume (P = 0.02). IAS was higher for group B than group A. CONCLUSIONS When implants are placed immediately after tooth extraction, I-BP may represent a useful diagnostic parameter in choosing the most appropriate grafting procedure (IG versus IEG). In clinical cases in which the distance between implant surface and the buccal plate is <4 mm, the combination of internal and external grafting (IEG) is recommended to maintain the volume and the contour of the ridge and achieve a successful esthetic outcome.

IL6 and IL10 are genetic susceptibility factors of periodontal disease.

Background: Periodontitis is a disease mainly caused by a chronic infection of tissues that support the teeth. Several factors, such as diabetes, smoking and oral care, as well as genetic susceptibility can influence both the risk to develop periodontitis and its progression. The aim of the investigation was to test whether alleles of candidate genes were associated with periodontitis. Materials and Methods: A case control study was performed with a cohort of 184 patients with chronic periodontitis and 231 healthy controls from the Italian population. A total of six single nucleotide polymorphisms from five candidate genes, i.e., IL1A, IL1B, IL6, IL10 and vitamin D receptor, were investigated. Results: Evidence of association were obtained for rs1800795 mapping in IL6 (P value = 0.01) as well as for the rs1800872 mapping in IL10 (P = 0.04). The rarer variant allele lowered the risk to develop periodontitis at IL6 (Odds Ratio [OR] = 0.69 [95% confidence interval {CI} 0.51-0.93]) and increased the risk at IL10 (OR = 1.38 [95% CI 1.01-1.86]). Conclusions: The present investigation indicated that polymorphisms of IL6 and IL10 constitute risk factors for chronic periodontitis, while there was no evidence implicating a specific IL1A or IL1B genotype.

Immediate versus Conventional Loading of Post-Extraction Implants in the Edentulous Jaws

PURPOSE This retrospective study deals with the issue of how to realize the transition from a failing dentition to an implant-supported prosthesis. The main aim was to assess the reliability of immediate implant and immediate loading (IL) protocols in the edentulous jaws. A further aim was to investigate the role of patient-related, implant-related, and surgery-related secondary variables in the occurrence of implant failure. MATERIALS AND METHODS Patients with at least a 4-year post-loading follow-up undergoing the transition from a failing dentition to an implant-supported prosthesis were retrospectively investigated. Primary variables of implant failure were immediate placement and IL. Secondary variables were categorized as demographic, anatomic, site, and prosthetically related. Cumulative survival rates (CSRs) were compared using the Kaplan-Meier survival estimate method. Predictors of failure were included in a multivariate Cox regression model to evaluate the simultaneous effects of multiple covariates and control for correlated observation. Crestal bone loss was also measured at the delayed and the immediately loaded implants. RESULTS Five hundred nineteen implants rehabilitating 91 jaws in 80 patients were followed. The Kaplan-Meier survival estimate method showed that immediate implant and IL decreased the CSR significantly in the maxilla but not in the mandible. Some secondary variables were found to affect the CSR: maxillary location, age over 70 years, prostheses supported by only immediate implants or a majority of them, temporary cementation, implant diameter, and length. Crestal bone loss was not significantly related to the outcomes. CONCLUSIONS The present data may provide clinical recommendations to the practitioner treating the transitional patient. In the mandible, the use of immediate implants and IL does not increase the failure rate. In the maxilla however, combining immediate placement and IL may significantly increase the failure rate.

The topical administration of bisphosphonates in implant surgery: a randomized split-mouth prospective study with a follow-up up to 5 years.

OBJECTIVE To evaluate the efficacy of the topical administration of bisphosphonates in implant therapy. MATERIALS AND METHODS Thirty-nine consecutive patients were selected for a split-mouth study. Inclusion criteria were: presence of a bilateral or total edentulism, ability to tolerate conventional implant procedures, older than 18 years. Ten patients were smokers. Ten patients were fully edentulous in both maxilla and mandible, 12 patients had fully edentulous maxilla or mandible, and 17 were bilaterally partially edentulous (9 in the mandible and 8 in the maxilla). A one-stage procedure was adopted in all cases. The prosthetic phase started 10 weeks after implant insertion. Each patient received implants on the control side and the test side, with insertion performed in the conventional way on the control side; on the test side, a 3% clodronate solution mixed with a surfactant (Tween-20) at a 1:3 ratio was topically administered both at the implant surface and at the implant site. RESULTS One hundred fifty-five implants were inserted. The test and control groups included 75 and 80 implants, respectively. The implant insertion torque was no less than 30 Ncm. A total of 7 implants failed in the control group (6 before loading and one after 12 months of loading). No failure occurred on the test side. By the 5-year follow-up, no further implant failure had been recorded. Overall, implant survival rates at 5 years for the test and control groups were, respectively, 100% and 91.3%, the difference being significant (p < .01). Mean marginal bone loss was 0.85 ± 0.71 mm in the test group and 1.12 ± 0.85 mm in the control group after 1 year of loading and stable thereafter. The difference was not significant. CONCLUSIONS The topical administration of bisphosphonates may positively affect implant survival in the preloading and postloading phases in partially and fully edentulous patients. However, a larger study population is needed to verify these promising clinical results.

Microflora and periodontal disease.

Background: Periodontitis is a disease that affects and destroys the tissues that support teeth. Tissue damage results from a prolonged inflammatory response to an ecological shift in the composition of subgingival biofilms. Three bacterial species that constitute the red complex group, Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola, are considered the main pathogens involved in periodontitis. Materials and Methods: In the present study, a real-time polymerase chain reaction bases assay was designed to detect and quantify red complex species, then used to investigate 307 periodontal pocket samples from 127 periodontitis patients and 180 controls. Results: Significant higher prevalence of red complex species and increased amount of P. gingivalis and T. denticola were detected in periodontal pocket of periodontitis patients. Conclusions: Results demonstrated that the test is a valuable tool to improve diagnosis of periodontal disease.

Post‐extraction implant placement into infected versus non‐infected sites: A multicenter retrospective clinical study

PURPOSE The aim of this study was to assess whether immediate implant placement into post-extraction sites presenting a chronic infection poses a greater risk of implant failure than immediate placement in non-infected sites. MATERIALS AND METHODS Records of patients who underwent extraction and immediate implant placement into both infected and non-infected sites from January 1998 to September 2014 at 5 different dental centers were considered for inclusion. Included records were subjected to statistical analysis of survival rates, along with a number of other patient-, implant-, surgery-, and prosthesis-related variables. RESULTS The inclusion criteria were met by 369 patients who received a total of 527 implants. The follow-up averaged 53.2 months (range 0.9-158.3) for implants placed into non-infected sockets (N = 334) and 50.1 months (range 1.6-146.1) for those placed into infected sites (N = 193). Seven implants failed in non-infected sites and 3 in infected ones. All failures occurred within 1 year of placement. Cumulative implant survival rate for non-infected and infected sites was, respectively, 97.9% ± 0.8% and 98.4% ± 0.9%, being not significantly different (P = .66). None of the investigated variables affected the outcome. CONCLUSIONS Placement of implants into periodontally or endodontically infected sites immediately after tooth extraction is a safe option, even when the implants are loaded immediately or early.

A Retrospective Analysis of the Effectiveness of the Longevity Protocol for Assessing the Risk of Implant Failure

BACKGROUND A new, computerized diagnostic tool, called the Longevity Protocol, was recently developed to predict implant failure. The present retrospective analysis was undertaken to assess the prognostic validity of this protocol. MATERIALS AND METHODS A selected group of patients who had been treated with implants over the past 10 years at six dental clinics and experienced implant failure were included in the analysis. Another group of patients with similar characteristics, not experiencing implant failure, was used as control. In April of 2015, data about each of the patients was entered into the Longevity Protocol database. For each patient, the risk assessment produced by the protocol was compared to whether the implants eventually failed. The implant failure predictions and actual implant failures were compared. RESULTS The Longevity Protocol analyzed the possible failure of 595 implants placed in 221 patients (323 implants placed in 138 patients classified as low risk, 180 implants placed in 55 patients classified as moderate risk, and 92 implants placed in 28 patients classified as high risk). The actual percentage of implant failure in the three groups was 10%, 15%, and 22%, respectively. The differences between the groups were statistically significant. The sensitivity and specificity of the Longevity Protocol was 84.9% and 11.90% in the high/moderate risk group and 47.17% and 32.74% in the low risk group, respectively. CONCLUSIONS Statistically significant results were obtained. The Longevity Protocol reliably identified patients who risked implant failure. The protocol appears to be an important tool for prognosis assessment.