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Implant Prophylaxis: The Next Best Practice Toward Asepsis in Spine Surgery.
Study designA literature review.ObjectivesAn evaluation of the contaminants prevalent on implants used for surgery and the aseptic methods being employed against them.MethodsPubMed was searched for articles published between 2000 and 2017 for studies evaluating the contaminants present on spine implants, and associated pre- and intraoperative implant processing and handling methodology suggested to avoid them. Systematic reviews, observational studies, bench-top studies, and expert opinions were included.ResultsEleven studies were identified whose major focus was the asepsis of implants to reduce the incidence of surgical site infection incidences during surgery. These studies measured the colony forming units of bacteria on sterilized implants and/or gloves from the surgeon, scrub nurse, and assistants, as well as reductions of surgical site infection rates in spine surgery due to changes in implant handling techniques. Additionally, the search included assessments of endotoxins and carbohydrates present on reprocessed implants. The suggested changes to surgical practice based on these studies included handling implants with only fresh gloves, keeping implants covered until the immediate time of use, reducing operating room traffic, avoiding reprocessing of implants (ie, providing terminally sterilized implants), and avoiding touching the implants altogether.ConclusionsBoth reprocessing (preoperative) and handling (intraoperative) of implants seem to lead to contamination of sterilized implants. Using a terminally sterilized device may mitigate reprocessing (preoperative implant prophylaxis), whereas the use of fresh gloves for handling each implant and/or a permanent shielding technique (intraoperative implant prophylaxis) could potentially avoid recontamination at the theatre
Osseointegration of zirconia implants compared with titanium : an in vivo study
Background Titanium and titanium alloys are widely used for fabrication of dental implants. Since the material composition and the surface topography of a biomaterial play a fundamental role in osseointegration, various chemical and physical surface modifications have been developed to improve osseous healing. Zirconia-based implants were introduced into dental implantology as an altenative to titanium implants. Zirconia seems to be a suitable implant material because of its tooth-like colour, its mechanical properties and its biocompatibility. As the osseointegration of zirconia implants has not been extensively investigated, the aim of this study was to compare the osseous healing of zirconia implants with titanium implants which have a roughened surface but otherwise similar implant geometries. Methods Forty-eight zirconia and titanium implants were introduced into the tibia of 12 minipigs. After 1, 4 or 12 weeks, animals were sacrificed and specimens containing the implants were examined in terms of histological and ultrastructural techniques. Results Histological results showed direct bone contact on the zirconia and titanium surfaces. Bone implant contact as measured by histomorphometry was slightly better on titanium than on zirconia surfaces. However, a statistically significant difference between the two groups was not observed. Conclusion The results demonstrated that zirconia implants with modified surfaces result in an osseointegration which is comparable with that of titanium implants
Short Implants Had Lower Survival Rates in Posterior Jaws Compared to Standard Implants
Data sources
PubMed/Medline, Embase and Cochrane Library databases supplemented by searches of the journals; Clinical Implant Dentistry and Related Research, Clinical Oral Implants Research, International Journal of Oral and Maxillofacial Implants, International Journal of Oral and Maxillofacial Surgery, Journal of Clinical Periodontology, Journal of Dentistry, Journal of Oral and Maxillofacial Surgery, Journal of Oral Implantology, Journal of Oral Rehabilitation, Journal of Periodontology, Periodontology 2000. Study selection
Randomised controlled trials (RCTs) and prospective studies with at least ten patients, published in the last ten years that compared short and standard implants and published in English were considered. Data extraction and synthesis
A single author abstracted data with checking by a second reviewer. Methodological quality was assessed using the Jadad Scale and the Cochrane risk of bias tool. Risk ratios (RR) were calculated for implant survival rates, complications and prostheses failures and marginal bone loss was evaluated using mean difference (MD). Results
Thirteen studies consisting of ten RCTs and three prospective studies were included. The ten RCTs were considered to be of high quality. Two thousand six hundred and thirty-one implants were placed in 1269 patients (981 short and 1650 standard implants). Thirty-eight short implants failed (3.87%) and 45 standard implants (2.72%). Random effects meta-analysis found no statistically significant difference between standard implants and short implants placed in the posterior regions; RR =1.35 (95% CI; 0.82-2.22: P=0.24). Marginal bone loss was evaluated in nine studies and no differences in marginal bone loss were observed. Complications were reported by seven studies and no significant difference was seen between standard and short implants; RR= 0.54 (95% CI; 0.27-1.09: P = 0.08). There was also no significant difference in prosthesis failures between standard and short implants; RR= 0.96 (95% CI: 0.44–2.09: P = 0.92) Conclusions
Short implants showed marginal bone loss, prosthesis failures and complication rates similar to standard implants, being considered a predictable treatment for posterior jaws, especially in cases that require complementary surgical procedures. However, short implants with length less than 8 mm (4-7 mm) should be used with caution because they present greater risks for implant failures when compared to standard implants
Platform Switching of Implants May Decrease Bone Loss
Data sources: PubMed/Medline, Web of Science and the Cochrane Oral Health Group Trials Register, clinicaltrials.gov, www.centerwatch.com/clinical-trials, www.clinicalconnection.com supplemented by a manual search of dental implants-related journals.
Study selection: Clinical studies, either randomised or not, comparing implant failure rates, marginal bone level (MBL) and/or postoperative infection in any group of patients receiving platform-switched implants or platform-matched implants were considered.
Data extraction and synthesis: Study quality was assessed using the Newcastle-Ottawa scale (NOS).Only randomised clinical trials (RCTs) were considered for meta-analysis. Implant failure and postoperative infection were the dichotomous outcomes measures evaluated. Weighted mean differences were used for MBL.
Results: Twenty-eight studies (18 RCTs, six CCTs and four retrospective analyses) were included. Twenty-six studies were considered to be of high quality. Twelve hundred and sixteen platform-switched implants were included with 16 failures (1.32%) and 1157 platform-matched implants and 13 failures (1.12%). Twenty studies had no implant failures. In a meta-analysis for the outcome MBL (18-RCTs) there was less MBL loss at implants with platform-switching than at implants with platform-matching (mean difference -0.29, 95% CI −0.38 to −0.19; P\u3c0.00001)
Conclusions: The results of the present study suggest that there is a significantly less MBL loss at implants with platform-switching than on implants with platform-matching. The results of the present review should be interpreted with caution due to the presence of uncontrolled confounding factors in the included studies, most of them with short follow-up periods
Effect of fluoride on the calcification of allogenic bone implants in rats
Thesis (M.Sc.D.)--Boston University School of Graduate Dentistry, 1974. Periodontics.Bibliography included.In twenty-five (25) male adult rats which had decalcified
allogenic bone implants placed in mid-fibular gaps
and kept on a low-fluoride casein diet (1 ppm- fluoride),
the addition of 25 p.p.m. fluoride to the drinking water
did not show any direct detectable relationship to the
mg % calcium in the ashed implants or in ashed adjacent
tibial bone, nor in the percent ash content.
Neither did the fluoride enhance or inhibit the success
of the implants. For all implants did calcify and
only one control mid-fibular gap closed on its own. It
is our conclusion that fluoride at levels used in this
experiment have no effect on calcification of allogenic
bone implants
Use of long implants with distal anchorage in the skull base for treatment of extreme maxillary atrophy : the remote bone anchorage concept
The objectives of this study are to present a new concept of the bone anchorage using long implants in remote bone sites and to discuss four cases treated with this method. Our patients were treated with long implants with a distant anchorage in the skull bone. The planning procedure, the construction of the drill guide, and the surgical protocol are described. In the clinical cases described, all four patients were rehabilitated with the remote bone anchorage concept using long implants anchored in the skull base. Patients were followed for 5 - 12 years and the implants remained present and stable in these time periods. The skull base implant is a new concept of bone anchorage using long implants. It can be a solution for complicated clinical situations (often failed bone reconstructions and implant placements) or an alternative for bone grafting and maxillary augmentation procedures. There is effective implant retention in the skull base, an anatomical area that is often overlooked for implant placement
Implant Treatment in the Predoctoral Clinic: A Retrospective Database Study of 1091 Patients
Purpose: This retrospective study was conducted at the Marquette University School of Dentistry to (1) characterize the implant patient population in a predoctoral clinic, (2) describe the implants inserted, and (3) provide information on implant failures.
Materials and Methods: The study cohort included 1091 patients who received 1918 dental implants between 2004 and 2012, and had their implants restored by a crown or a fixed dental prosthesis. Data were collected from patient records, entered in a database, and summarized in tables and figures. Contingency tables were prepared and analyzed by a chi-squared test. The cumulative survival probability of implants was described using a Kaplan-Meier survival curve. Univariate and multivariate frailty Cox regression models for clustered observations were computed to identify factors associated with implant failure.
Results: Mean patient age (±1 SD) at implantation was 59.7 ± 15.3 years; 53.9% of patients were females, 73.5% were Caucasians. Noble Biocare was the most frequently used implant brand (65.0%). Most implants had a regular-size diameter (59.3%). More implants were inserted in posterior (79.0%) than in anterior jaw regions. Mandibular posterior was the most frequently restored site (43%); 87.8% of implants were restored using single implant crowns. The overall implant-based cumulative survival rate was 96.4%. The patient-based implant survival rate was 94.6%. Implant failure risk was greater among patients than within patients (p \u3c 0.05). Age (\u3e65 years; hazard ratio [HR] = 3.2, p = 0.02), implant staging (two-stage; HR = 4.0, p \u3c 0.001), and implant diameter (wide; HR = 0.4, p = 0.04) were statistically associated with implant failure.
Conclusions: Treatment with dental implants in a supervised predoctoral clinic environment resulted in survival rates similar to published results obtained in private practice or research clinics. Older age and implant staging increased failure risk, while the selection of a wide implant diameter was associated with a lower failure risk
Flexible (Polyactive®) versus rigid (hydroxyapatite) dental implants
In a beagle dog study, the peri-implant bone changes around flexible (Polyactive®) and rigid hydroxyapatite (HA) implants were investigated radiographically by quantitative digital subtraction analysis and by assessment of marginal bone height, with the aid of a computerized method. A loss of approximately 1 mm of marginal bone height was observed for both the dense Polyactive and the HA implants, after 6 months of loading. This value appeared to be stable from 12 weeks of loading onward. Along the total length of the implant during the first 6 weeks of loading, both the flexible (dense Polyactive) and the rigid (HA) implants showed a decrease in density. However, after this 6-week period, the bone density around the implants increased, and after 18 weeks the original bone density was reached. The flexible Polyactive implants provoked less decrease in density than the rigid HA implants, although not to a statistically significant level. This finding sustains the hypothesis that flexible implant materials may transfer stresses to the surrounding bone more favorably
The impact of loads on standard diameter, small diameter and mini implants: A comparative laboratory study
Objectives: While caution in the use of small-diameter (≤3.5 mm) implants has been advocated in view of an increased risk of fatigue fracture under clinical loading conditions, a variety of implant designs with diameters <3 mm are currently offered in the market for reconstructions including fixed restorations. There is an absence of reported laboratory studies and randomized-controlled clinical trials to demonstrate clinical efficacy for implant designs with small diameters. This laboratory study aimed to provide comparative data on the mechanical performance of a number of narrow commercially marketed implants. Materials and methods: Implants of varying designs were investigated under a standardized test set-up similar to that recommended for standardized ISO laboratory testing. Implant assemblies were mounted in acrylic blocks supporting laboratory cast crowns and subjected to 30° off-axis loading on an LRX Tensometer. Continuous output data were collected using Nexygen software. Results: Load/displacement curves demonstrated good grouping of samples for each design with elastic deformation up to a point of failure approximating the maximum load value for each sample. The maximum loads for Straumann (control) implants were 989 N (±107 N) for the 4.1 mm RN design, and 619 N (±50 N) for the 3.3 mm RN implant (an implant known to have a risk of fracture in clinical use). Values for mini implants were recorded as 261 N (±31 N) for the HiTec 2.4 mm implant, 237 N (±37 N) for the Osteocare 2.8 mm mini and 147 N (±25 N) for the Osteocare mini design. Other implant designs were also tested. Conclusions: The diameters of the commercially available implants tested demonstrated a major impact on their ability to withstand load, with those below 3 mm diameter yielding results significantly below a value representing a risk of fracture in clinical practice. The results therefore advocate caution when considering the applicability of implants ≤3 mm diameter. Standardized fatigue testing is recommended for all commercially available implants
Retrospective comparative study of bone loss in implants with and without immediate loading in the Egas Moniz university clinic
To evaluate bone loss after three years in implants placed at the implantology consult at the Egas Moniz University Clinic, relating bone loss to the type of loading (conventional or immediate load). A comparative and retrospective study, performed on a sample of 65 implants, placed in 24 of 327 patients, who attended the implantology consult at the Egas Moniz University Clinic in 2015, representing 7.3% of the study population through the measurement of distance between implant platform and bone using radiographs. Three years after implant placement with and without immediate loading there is statistically significant bone loss mesially and distally. It was found that when compared bone loss in loaded vs unloaded mesially and distally implants, there were no statistically significant differences. The bone loss of the unloaded implants was compared three years after being placed, with the bone level of the loaded implants also three years later. No significant difference was found. Although no statistically significant differences were found between bone loss in loaded implants vs unloaded mesially and distally, as it is supported by the literature, it was possible to conclude that there was, in fact, a statistically significant bone loss, mesially and distally, three years after implant placement with and without immediate loading. This may be due to poor oral hygiene, a history of periodontitis, smoking and peri-implantitis.info:eu-repo/semantics/publishedVersio
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