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Despite reductions in bacterial infection and enhanced success rate, the widespread use of systemic antibiotic prophylaxis in implant dentistry is controversial. This use has contributed to the growing problem of antimicrobial resistance, along with creating significant health and economic burdens. The basic mechanisms that cause implant infection can be targeted by new prevention and treatment methods which can also lead to the reduction of systemic antibiotic exposure and its associated adverse effects. This review aims to summarize advanced biomaterial strategies applied to implant components based on anti-pathogenic mechanisms and immune balance mechanisms. It emphasizes that modifying the dental implant surface and regulating the early immune response are promising strategies, which may further prevent or slow the development of peri-implant infection, and subsequent failure. [ABSTRACT FROM AUTHOR]

Noninvasive dental diagnostics is a growing discipline since it has been established that early detection and quantification of tooth mineral loss can reverse caries lesions in their incipient state. A theoretical coupled diffuse photon density and thermal-wave model was developed and applied to photothermal radiometric frequency responses, fitted to experimental data using a multiparameter simplex downhill minimization algorithm for the extraction of optothermophysical properties from artificially demineralized human enamel. The aim of this study was to evaluate the reliability and robustness of the advanced fitting algorithm. The results showed a select group of optical and thermal transport parameters and thicknesses were reliably extracted from the computational fitting algorithm. Theoretically derived thicknesses were accurately predicted, within about 20% error, while the estimated error in the optical and thermal property evaluation was within the values determined from early studies using destructive analyses. The high fidelity of the theoretical model illustrates its efficacy, reliability, and applicability toward the nondestructive characterization of depthwise inhomogeneous sound enamel and complex enamel caries lesions. [c] 2010 Optical Society of America OCIS codes: 170.1850, 170.7050, 160.4760, 170.5270, 170.6935, 190.4870.

Purpose: To assess the three-dimensional (3D) accuracy and clinical acceptability of implant definitive casts fabricated using a digital impression approach and to compare the results with those of a conventional impression method in a partially edentulous condition. Materials and Methods: A mandibular reference model was fabricated with implants in the first premolar and molar positions to simulate a patient with bilateral posterior edentulism. Ten implant-level impressions per method were made using either an intraoral scanner with scanning abutments for the digital approach or an open-tray technique and polyvinylsiloxane material for the conventional approach. 3D analysis and comparison of implant location on resultant definitive casts were performed using laser scanner and quality control software. The inter-implant distances and interimplant angulations for each implant pair were measured for the reference model and for each definitive cast (n = 20 per group); these measurements were compared to calculate the magnitude of error in 3D for each definitive cast. The influence of implant angulation on definitive cast accuracy was evaluated for both digital and conventional approaches. Statistical analysis was performed using t test (α = .05) for implant position and angulation. Clinical qualitative assessment of accuracy was done via the assessment of the passivity of a master verification stent for each implant pair, and significance was analyzed using chi-square test (α = .05). Results: A 3D error of implant positioning was observed for the two impression techniques vs the reference model, with mean ± standard deviation (SD) error of 116 ± 94 μm and 56 ± 29 μm for the digital and conventional approaches, respectively (P = .01). In contrast, the inter-implant angulation errors were not significantly different between the two techniques (P = .83). Implant angulation did not have a significant influence on definitive cast accuracy within either technique (P = .64). The verification stent demonstrated acceptable passive fit for 11 out of 20 casts and 18 out of 20 casts for the digital and conventional methods, respectively (P = .01). Conclusion: Definitive casts fabricated using the digital impression approach were less accurate than those fabricated from the conventional impression approach for this simulated clinical scenario. A significant number of definitive casts generated by the digital technique did not meet clinically acceptable accuracy for the fabrication of a multiple implant-supported restoration. [ABSTRACT FROM AUTHOR]

Purpose:To compare the in vitro 3-dimensional (3D) accuracy of fit of laser-scanned Computer Numeric Controlled (CNC)--milled implant titanium frameworks to that of conventional cast frameworks. Materials and Methods: Nine cast frameworks were fabricated on the mandibular master casts of 9 patients with 5 implants each following the well-established conventional fabrication technique. The frameworks were then laser scanned, and 9 CNC-milled titanium frameworks matching the outline of the conventional frameworks were fabricated. The accuracy of fit of both framework types was measured using a contact-type coordinate measuring machine and a computer program developed specifically for this purpose. Statistical analysis was done by a series of paired ttests. Results:The laser-scanned CNC-milled frameworks showed significantly less distortion along the x-axis (transversal, dx) compared with the conventional frameworks (means: 33.7µm and 49.2 µm, respectively) ( P= .011). The titanium frameworks also demonstrated significantly less distortion on the horizontal plane compared with the conventional frameworks (means: 56 µm and 85 µm, respectively) ( P= .012). The dy (sagittal) and dz (vertical) axes and total 3D distortion (√ dx² + dy² + dz²) showed less distortion overall in the laser-scanned CNC-milled frameworks, but this was not statistically significant (mean: 22.3 vs 35.6 µm, 13.3 vs 59.2 µm, 51 vs 114.1 µm, respectively, for y, z, and 3D distortion). Conclusion:Within the limitations of this study, fabrication of an implant-prosthodontic framework using the CNC milling technique yields a more accurate fit than the currently used cast technique. In vivo studies are needed to investigate the clinical significance of this recorded difference. [ABSTRACT FROM AUTHOR]

Purpose: To compare the clinical outcomes of immediate versus conventional delayed loading of four dental implants in edentulous mandibles with fixed prostheses. Materials and methods: A blinded, two-arm, parallel group, randomised controlled trial was conducted. A total of 42 patients were included, and each received four Brånemark System implants with a TiUnite surface. The patients were randomly assigned to two study arms: 1) immediateloading arm (IL), in which the mandibular denture was converted into an interim implant-supported fixed prosthesis (ISFP) on the day of surgery, with a permanent ISFP being inserted at least 3 months postsurgery; 2) conventional-loading arm (CL), in which the mandibular removable prosthesis was relieved at the implant site and relined with a soft tissue conditioner. Only implants with a minimum insertion torque of = 35 Ncm were included in the IL group. Implants were loaded 4 to 6 months postsurgery. Independent, blind investigators assessed the patients at 2, 6 and 12 months and at 10 years. The outcome measures were prosthesis and implant success rates, type and frequency of complications and changes in peri-implant marginal bone levels. Results: A total of 20 patients were allocated to the IL group and 22 to the CL group. However, one patient from the IL arm was excluded and three patients were reallocated to the CL arm. Two implants in one patient and one in another patient could not be placed with a = 35 Ncm insertion torque, and a third patient developed severe sudden gag reflex and thus it was not possible to load the implants immediately. At a later stage, one of the patients who failed the initial stability test dropped out of the study. Therefore, initially, 24 patients were conventionally loaded and 16 patients were immediately loaded. At the 10-year follow-up, six patients dropped out from the IL arm and two from the CL arm. Also, at the 10-year-follow-up, the CL and IL study arms consisted of 22 and 10 participants, respectively, using the per-protocol (PP) analysis. Six implants failed in two patients of the CL arm (two implants in one patient and four implants in another patient), and three implants failed in three patients in the IL arm (PP analysis), respectively. The patient-level implant failure rate was 10% (intention-to-treat [ITT] analysis) and 14% (PP analysis) in the CL arm, and 25% (ITT) and 20% (PP) in the IL arm. The difference was not statistically significant (95% CI from -0.18 to 0.39, P = 0.65). The failure rate at the implant level was 8% (ITT) and 8% (PP) in the CL arm, and 6% (ITT) and 5% (PP) in the IL arm. The difference was not statistically significant (95% CI from -0.06 to 0.14, P = 0.44). Ten years after loading, patients in the IL arm lost an average of 0.55 ± 0.64 mm of peri-implant bone versus 0.41 ± 0.40 mm of peri-implant bone loss observed in the CL arm. The 10-year bone loss in both arms was statistically significant compared with the baseline (P < 0.001). However, there was no statistically significant difference between the two arms for peri-implant bone level changes (the difference between the arms was 0.14 mm ± 0.50 mm; 95% CI --0.23 to 0.52; P = 0.43). One prosthesis failed due to the loss of all four implants in one patient of the CL arm. Eight patients from the IL arm were affected by 13 complications (such as pain from fractures and inflammation) versus seven patients (10 complications) from the CL arm. The complication rate was 67% in the IL arm and 35% in the CL arm. The difference in complication proportions between the two arms was not statistically significant (difference in proportions = 0.32; 95% CI = --0.08 to 0.61; P = 0.14). All complications were managed successfully. Conclusions: Long-term data of immediate loading of four dental implants with a mandibular fixed prosthesis revealed comparable clinical outcomes to conventional loading. Therefore, immediate loading should be considered in the treatment of edentulous patients. [ABSTRACT FROM AUTHOR]