No abstract

Immediate loading of oral implants has become popular because of the increasing demands of a shortened treatment time. This literature review evaluates the prognosis of immediately loaded implants and their restorations with immediate or delayed implant placement. Special attention was given to the impact of type of jaw, bone quality, implant length, time of implant placement and type of restoration. An electronic (PubMed) and a manual search in relevant journals were conducted until February 2012. Only publications in English, in peer-reviewed journals, were considered. Nine studies met the inclusion criteria: five studies dealt with fixed restorations, two studies with removable rehabilitation of edentulous jaws and two studies dealt with partially edentulous patients. Implant survival rates ranged from 95·8% to 100%, implant success rates in the treatment for the mandible from 79% to 100% and restoration survival rates for both jaws from 96·4% to 100%. Within the limits of this review, appropriate patient selection, primary implant stability, splinting of implants and the expertise of surgeons seem to be important for the prognosis of immediately loaded implants and their restorations. Good bone quality and use of long implants appear to play a role. However, careful interpretation is required because conclusions are based on articles with low level of evidence. While immediate loading of oral implants in the mandible shows encouraging and predictable results, further multicenter randomised controlled clinical trials with sufficient statistical power are needed to examine (i) the outcome of immediately loaded implants in the maxilla and (ii) the outcome of immediate loading of immediately placed implants.

Ultraviolet (UV) light treatment of implant surfaces has been demonstrated to enhance their bioactivity significantly. This study examined the effect of UV treatment of different zirconia surfaces on the response of primary human alveolar bone-derived osteoblasts (PhABO). Disks of two zirconia-based materials with two different surface topographies (smooth, roughened) were exposed to UV light. Qualitative and quantitative assessment of PhABO on zirconia surfaces, by means of immunofluorescence, scanning electron microscopy and DNA quantification at 4 and 24 h revealed a higher number of initially attached osteoblasts on UV-treated surfaces. Cell area and perimeter were significantly larger on all UV-treated surfaces (p < 0.05). The proliferation activity was significantly higher on both roughened UV-treated surfaces than on untreated samples at day 3 of culture (p < 0.05). The expression levels of collagen I, osteopontin and osteocalcin at day 14 and alkaline phosphatase activity at day 7 and 14 of culture period were similar among UV-treated and untreated surfaces. Alizarin-Red-Staining at day 21 demonstrated significantly more mineralised nodules on UV-treated samples than on untreated samples. Contact angle measurements and X-ray photoelectron spectroscopy showed that UV light transformed zirconia surfaces from hydrophobic to (super-) hydrophilic (p < 0.05) and significantly reduced the atomic percentage of surface carbon. The results showed that UV light pre-treatment of zirconia surfaces changes their physicochemical properties and improves their attractiveness against PhABO, primarily demonstrated by an augmented cell attachment and spreading. This may result in faster healing and better bone-to-implant contact of zirconia implants in vivo following such a pre-treatment.

Objective: Improvements in the bioactivity of zirconia implants for accelerated healing and reduced morbidity have been of continuing interest in the fields of dentistry and orthopedic surgery. The aim of the present study was to examine whether UV treatment increases the osteoconductivity of zirconia-based materials. Materials and Methods: Smooth and rough zirconia-based disks and cylindrical implants were treated with UV light for 15 min and subsequently placed in rat femurs. Surface characterization was performed using scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and contact angle measurements. Results: In vivo histomorphometry revealed that the percentage of bone-implant contact and the amount of bone volume, formed around UV-treated implants, increased by 3–7-fold for smooth surfaces and by 1.4–1.7-fold for rough surfaces compared to non-treated specimens at Weeks 2 and 4 of healing, respectively. A biomechanical test showed that UV treatment accelerated the establishment of bone-zirconia integration and enhanced the strength of the bone-implant interface by two-fold. Additionally, surface characterization of the zirconia disks revealed that UV treatment decreased the amount of surface carbon and converted the hydrophilic status from hydrophobic to superhydrophilic. Conclusions: This study indicates that UV light pretreatment enhances the osteoconductive capacity of zirconia-based materials.

The aims of this systematic review were to investigate the success rates of prosthetic restorations on endodontically treated teeth and their manner of failure. PubMed and hand literature searches were conducted on studies published until June 2012. Only clinical studies on human subjects referring to the success rates of prosthetic restorations on endodontically treated teeth with a follow-up period of at least 6 years were reviewed. A total of four studies were identified. Meta-analysis showed the success rate to be 92% (CI 82-98%) for single crowns on endodontically treated teeth and 79% (72-86%) for fixed dental prostheses. Only one study reported on removable dental prostheses with a success rate of 66%. Single crowns on teeth restored without posts demonstrated a success rate of 94% (CI 84-99%), whereas where posts were placed, the success rate was lower (92% CI 82-98%). Single crowns over cast post-and-cores and prefabricated posts showed success rates of 93% (CI 82-99%) and 94% (CI 90-97%), respectively; both differences were not statistically significant (significance level of 5%). The most common reason for failure was post-debonding. Single crowns seem to be the best treatment modality for endodontically treated teeth. However, due to the low number of studies included and their design, the results of this systematic review should be interpreted with caution. Further clinical studies are needed to provide high-quality evidence on the topic.

To ensure the long-term success of dental implants, a functional attachment of the soft tissue to the surface of the implant abutment is decisively important in order to prevent the penetration of bacteria into the implant-bone interface, which can trigger peri-implant disease. Here a surface modification approach is described that includes the covalent immobilization of the extracellular matrix (ECM) proteins fibronectin and laminin via a crosslinker to silanized Ti6Al4V and Y-TZP surfaces. The surface properties are evaluated using static contact angle, X-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM). The interaction of human gingival fibroblasts (HGFs) with the immobilized ECM proteins is verified by analyzing the localization of focal contacts, cell area, cell morphology, proliferation rate, and integrin expression. It is observed in the presence of fibronectin and laminin an increased cellular attachment, proliferation, and integrin expression of HGFs accompanied by a significantly higher number of focal adhesions. The presented approach holds great potential to enable a stronger bond between soft tissue and implant abutment surface. This could potentially help to prevent the penetration of bacteria in an in vivo application and thus reduce the risk of periimplant disease.

Objective To compare the radiographic marginal bone loss and clinical parameters of splinted and non‐splinted fixed dental prostheses on short implants in the posterior region of the lower jaw 3 years after loading. Material and Methods Twenty patients, 15 female and five males, with uni‐ or bilateral free‐end situations in the mandible participated in the study. Two short implants (7 mm) in the posterior mandible were placed and patients were randomized to receive splinted (n = 11) or non‐splinted (n = 13) cemented crowns. Marginal bone loss (MBL) was assessed on radiographs taken with customized positioning jigs at baseline, 1 and 3 years after loading. Plaque index (PI), gingival index (GI), probing depth (PD), and bleeding on probing (BOP) were measured. (ClinicalTrials.gov; identifier: NCT03558347). Results After 3‐year survival rate of altogether 48 implants was 100% for both groups. Success rate (according to Papaspyridakos, Chen, Singh, Weber, & Gallucci, 2012) was 84.6% for non‐splinted and 86.4% for splinted implants. At restoration level survival rate was 100% for both groups. Marginal bone level changes showed mean gain of 0.3 ± 0.8 mm for non‐splinted and 0.1 ± 0.5 mm for splinted implants 3 years after loading. Statistical analysis showed no significant difference in PI, GI, PD, BOP, and marginal bone loss between both groups (p > .05). Conclusion Within the limitations of this study it can be concluded that splinting crowns on short implants neither seems to affect the amount of marginal bone loss nor peri‐implant health 3 years after loading.

Aim of this review was to investigate the prognosis of implants inserted in augmented sinuses and fixed restorations supported by these implants. Special attention was given to the impact of grafting material, time of implant placement, residual bone height and type of fixed restoration. An electronic search in PubMed, the German database medpilot and the Cochrane Library was executed followed by supplementary manual search in relevant journals. The search was limited to human studies published up to November 2010. Only publications in English and German, in peer-reviewed journals, were considered. After the initial search and application of selection criteria on titles and abstracts, a full-text analysis of 67 articles was performed, out of which six prospective and three retrospective studies were finally included in the review. The heterogeneous properties of the identified articles did not allow systematic analysis of the data. Success rates of implants were between 96·3% and 100%, survival rates were between 75% and 100%, and survival rates of single crowns, splinted crowns and fixed partial dentures ranged between 96·4% and 100% after a follow-up of 12-101 months. Within the limits of this review, the prognosis of implants and fixed restorations seemed not to be influenced by the type of restorations, graft material, residual bone height and time of implant placement. However, conclusions of this review are based on studies with low level of evidence; therefore, careful interpretation is required. Multicentre randomised controlled clinical trials with sufficient statistical power concentrating on few factors are needed to reach sound conclusions.