Paolo Pesce

Systematic review of some prosthetic risk factors for periimplantitis

STATEMENT OF PROBLEM The recent literature underlines a correlation between plaque and the development of periimplantitis but neglects the importance of the prosthetic factors. PURPOSE The purpose of this systematic review was to appraise the available literature to evaluate the role played by cement excess and misfitting components on the development of periimplantitis. MATERIAL AND METHODS An electronic search restricted to the English language was performed in PubMed, Embase, and the Cochrane Register up to September 1, 2014, based on a selected search algorithm. Only cohort studies and case-control studies were included without additional restrictions. The presence of periimplantitis and implant failure were considered primary and secondary outcome variables. RESULTS The search produced 275 potentially relevant titles, of which only 2 were found eligible. They showed a correlation in cemented implant prostheses between cement excess and the presence of periimplant disease, especially in patients with a history of periodontal disease. After cement excess removal by means of debridement, disease symptoms disappeared around most of the implants. CONCLUSIONS Scientific articles on prosthetic risk factors for periimplantitis are scarce. Although the studies found on cement remnants have a high risk for bias, cement excess seems to be associated with mucositis and possibly with periimplantitis, especially in patients with a history of periodontal disease.

Peri-implantitis: a systematic review of recently published papers.

PURPOSE This systematic review considers possible etiologic factors and definitions of peri-implantitis as reported in the recent literature. MATERIALS AND METHODS An electronic search of databases plus a hand search of the most relevant journals published between January 2005 and September 2012 were performed. RESULTS The electronic and manual searches yielded 640 and 14 titles, respectively. From the independent doublecheck of the titles and abstracts, 24 full texts were downloaded (18 clinical studies and 6 animal studies). After reading the full texts, 10 articles (4 clinical studies and 6 animal studies) were included in this review. None of the human articles selected provided sufficient evidence to address the research question, and no human clinical evidence is available to support a cause-effect relationship between peri-implantitis and bacterial accumulation and/or occlusal overload. The animal literature is also not unanimous regarding a specific peri-implantitis etiology. However, a correlation between periodontitis and smoking histories was cited as contributing to a higher incidence of peri-implantitis. CONCLUSION The available scientific literature is characterized by an absence of a unanimous consensus regarding the etiology of peri-implantitis and its specific relationship to periodontitis. Furthermore, both the choice of the term peri-implantitis and its definition remain controversial.

Immediate Versus Delayed Loading of Dental Implants in Edentulous Patients’ Maxillae:: A 6-Year Prospective Study

PURPOSE This study compared the surgical protocol efficacy of immediate and delayed implant loading in edentulous maxillae opposed by natural or restored mandibular dentitions over an observational period of 6 years or longer. The selected outcome determinants included individual implant survival data, progressive measurements of peri-implant bone resorption, prosthodontic survival and success data, and report of complications. MATERIALS AND METHODS A convenience sample of 49 patients requiring fixed implant-supported maxillary prostheses was split into two groups. The test group (34 patients) was treated according to the Columbus Bridge Protocol, which prescribes the insertion of four to six implants, including distally tilted implants, and load within 24 hours. The control group (15 patients) was treated via a two-stage surgical protocol of 6 to 9 straight implants that were loaded a mean 8.75 months after stage-one implant surgery. Two hundred sixty implants (test: n = 163, control: n = 97) were placed, and all subjects were ultimately treated with screw-retained full-arch prostheses. RESULTS Two patients dropped out (one in the test group and one in the control group) by the time of the scheduled sixth annual visit. The other patients were followed up for 75.2 months (range: 72 to 90 months). At the 6-year follow-up, no differences in implant cumulative survival rates were found between groups. Significantly less bone loss was found in the test group (mean: 1.62 mm) compared with the control group (mean: 2.44 mm). All of the original prostheses were maintained throughout the studys observation period and were functioning satisfactorily at each patients last recall appointment. CONCLUSION Patients who received immediate and delayed implant loading in their edentulous maxillae demonstrated similar survival outcomes. However, less marginal bone loss was recorded around the immediately loaded implants over the studys 6-year follow-up period.

Biological and mechanical characterization of carbon fiber frameworks for dental implant applications

OBJECTIVES The aim of the present study was to investigate the biocompatibility and mechanical characteristics of dental implant frameworks made of carbon fiber composite. METHODS The biocompatibility of intact samples and fragments was evaluated by cell count and MTT test according to EN-ISO 10993-5:2009 directions. Destructive and non-destructive mechanical tests were performed in order to evaluate: porosity, static and dynamic elastic modulus of carbon fiber samples. These tests were conducted on different batches of samples manufactured by different dental technicians. The samples were evaluated by optical microscope and by SEM. A compression test was performed to compare complete implant-supported fixed dentures, provided with a metal or carbon fiber framework. RESULTS Carbon fiber intact and fragmented samples showed optimal biocompatibility. Manufacture technique strongly influenced the mechanical characteristics of fiber-reinforced composite materials. The implant-supported full-arch fixed denture provided with a carbon fiber framework, showed a yield strength comparable to the implant-supported full-arch fixed denture, provided with a metal framework. SIGNIFICANCE Carbon fiber-reinforced composites demonstrated optimal biocompatibility and mechanical characteristics. They appear suitable for the fabrication of frameworks for implant-supported full-arch dentures. Great attention must be paid to manufacture technique as it strongly affects the material mechanical characteristics.

Factors affecting the outcome in the immediate loading rehabilitation of the maxilla: a 6-year prospective study.

This prospective study reports the 6-year outcomes for patients rehabilitated with an immediate loading protocol of the maxilla (Columbus Bridge Protocol). In this study, 164 implants were inserted in 37 patients and loaded within 24 to 36 hours. Four implants failed during the first 6 months. At the 6-year follow-up, a mean bone loss of 1.52 mm was found. Significantly (P < .0083) less bone loss was found next to tapered implants compared with cylindric implants and next to machined collar implants compared with full acid-etched implants (P < .0083). No significant differences in bone loss were found in tilted versus upright implants or in mesial versus distal implant sites. In addition, there were no significant differences relating to either the degree of abutment angulation or the reason for tooth loss.

Adhesive strength of the luting technique for passively fitting screw-retained implant-supported prostheses: an in vitro evaluation.

PURPOSE This in vitro study evaluated the adhesive strength of a technique to lute implant cylinders to metal frameworks in implant-supported prostheses and ensure a good passive fit. MATERIALS AND METHODS Different height samples were tested: In group 1, implant cylinders were 5 mm long; in group 2, they were 10 mm long. A universal testing machine (Instron) was used to perform pullout tests. RESULTS The luting technique provided enough adhesive strength for clinical use with greater adhesive strength in group 2 (mean pull-out strength: 2.85 kN in group 1 versus 3.79 kN in group 2). CONCLUSIONS The luting technique provides enough adhesive strength for clinical use. Moreover, specimens with a larger surface for adhesion demonstrated higher adhesive strength compared with shorter specimens.

A Luting Technique for Passive Fit of Implant-Supported Fixed Dentures

Several factors contribute to distortion of implant prostheses during fabrication and could prevent passive, accurate adaptation between implants and implant frameworks. The misfit between implants and restorative components may be significant and possibly lead to biologic or mechanical complications. The aim of this article is to describe a laboratory luting technique used to lute implant cylinders to metal frameworks in implant prostheses. This technique provides accurate, passive fits. According to this technique, titanium implant cylinders provided with corresponding external castable cylinders are used. Implant cylinders are screwed into the analogs in the master cast while the castable cylinders on top are splinted together using castable resin to realize a castable resin pattern. After casting, the framework is adjusted and cemented to the titanium cylinders on the master cast. Due to its ease and quickness of use and clinical efficiencies, this technique is deemed particularly useful in immediate loading rehabilitations.

Effect of Framework in an Implant-Supported Full-Arch Fixed Prosthesis: 3D Finite Element Analysis.

PURPOSE The aim of this study was to analyze through a three-dimensional finite element analysis (3D-FEA) stress distribution on four implants supporting a full-arch implant-supported fixed prosthesis (FFP) using different prosthesis designs. MATERIALS AND METHODS A 3D edentulous maxillary model was created and four implants were virtually placed into the maxilla and splinted, simulating an FFP without framework, with a cast metal framework, and with a carbon fiber framework. An occlusal load of 150 N was applied, stresses were transmitted into peri-implant bone, and prosthodontic components were recorded. RESULTS 3D-FEA revealed higher stresses on the implants (up to +55.16%), on peri-implant bone (up to +56.93%), and in the prosthesis (up to +70.71%) when the full-acrylic prosthesis was simulated. The prosthesis with a carbon fiber framework showed an intermediate behavior between that of the other two configurations. CONCLUSION This study suggests that the presence of a rigid framework in full-arch fixed prostheses provides a better load distribution that decreases the maximum values of stress at the levels of implants, prosthesis, and maxillary bone.

Third molars and dental crowding: different opinions of orthodontists and oral surgeons among Italian practitioners

BackgroundThe role of third molars as a cause of incisor crowding, especially in the lower arch, continues to be controversial. The aim of this work is to compare opinions of Italian oral surgeons and orthodontists on this topic.MethodsOne hundred ninety-three Italian practitioners of the Society of Orthodontics (SIDO) and the Italian Society of Oral Surgery (SICOI) were asked to fill out an online questionnaire made up of six questions. Practitioners were asked to express their opinion on the relation between upper and lower third molar eruption and anterior crowding.ResultsOne hundred sixty-six members of both societies completed the online research survey; response rate (RR) was 86%. There were no statistically significant differences between the two groups (P > 0.005). Both agree not to believe that third molars create a force responsible for anterior crowding in the upper (82.5% orthodontists, 83.8% surgeons) and in the lower arch (52.6% orthodontists, 63.8% surgeons). Both agree also not to consider the upper (89.7% orthodontists, 82.1% surgeons) and lower (58.8% orthodontists, 63.2% surgeons) third molar extraction useful to prevent crowding.ConclusionsItalian orthodontists and oral surgeons have the same opinion on the role of the third molar in causing anterior crowding. The majority of both groups of clinicians do not consider their preventive extraction useful in order to prevent anterior crowding.

Effects of pulsed electromagnetic fields on swelling and pain after implant surgery: a double-blind, randomized study

The aim of this split-mouth, double-blind, randomized study was to determine whether pulsed electromagnetic field therapy (PEMF) can improve swelling and the management of pain after full-arch immediate loading implant surgery. Eleven patients were selected for the study. Each patient received four distal tilted implants in the upper or lower jaw and underwent full-arch immediate loading rehabilitation. After surgery, two PEMF devices were applied to each patient, one on each cheek. In a random manner, one of these PEMF devices was switched on (test side); the other served as a placebo (control side). Forty-eight hours after surgery clinicians estimated postoperative swelling through photographic documentation, comparing the condition before and after surgery, while pain was assessed using a verbal rating scale. The patients degree of comfort in relation to the PEMF devices was analyzed by questionnaire using a numerical rating scale. No statistically significant difference was observed between the test and control sides for swelling or pain (P>0.05). Most of the patients did not present swelling or pain at 48h after surgery, regardless of whether the PEMF device was activated or not. Various outcomes were found in the comfort evaluation. Within the limitations of this study, PEMF does not reduce postoperative swelling or pain after implant surgery.