Sealing Socket Abutments (SSAs) in Molar Immediate Implants with a Digitalized CAD/CAM Protocol: Soft Tissue Contour Changes and Radiographic Outcomes After 2 Years.

Immediate implant placement in molar sites has the potential to improve the patient experience by reducing the number of appointments and the overall treatment time. However, primary closure remains a technical challenge. The present prospective case series evaluated the soft tissue contours and the radiographic bone levels of 17 patients who received immediate implants in molar sites and a digitally customized CAD/CAM sealing socket abutment. At the 2-year follow-up, the mean buccal tissue contours at the most coronal portion were reduced horizontally by an average of 1 mm at 1, 2, 3, and 4 mm below the gingival margin. A mean 0.53-mm apical migration of the gingival margin was seen, and the mean interproximal bone level at the 2-year follow-up was 0.89 mm. The use of CAD/CAM-generated customized healing abutments in immediate molar sites yielded minimal hard and soft tissue changes at the 2-year follow-up.

Immediate implant in the posterior region combined with alveolar ridge preservation and sealing socket abutment: A retrospective 3D radiographic analysis.

BACKGROUND: Customized sealing socket abutment (SSA) has been claimed to optimize the peri-implant hard and soft tissues in type 1 implant placement. However, the evidence to claim the benefits of this technique over the use a conventional healing abutment remains weak. PURPOSE: The aim of this retrospective study was to provide a 3D-radiographic evaluation of hard tissues changes following immediate implant placement in molar sites combined to ARP technique and installation of SSA. MATERIALS AND METHODS: Baseline and follow-up (FU) CBCTs (from 1 to 5 years) of 26 patients were collected and included in the study. Baseline and FU CBCTs were superimposed and horizontal and vertical bone changes were assessed. RESULTS: A total of 26 patients and 27 implants were included. Horizontal bone remodeling was not significant in any of the measured areas except in the most cervical level, where a mean bone remodeling of 0.73 mm was found. Proximal and buccal vertical bone changes were not significant. CONCLUSIONS: Within the limits of a retrospective study, dimensional alveolar ridge changes 1 to 5 years after immediate implant placement in molar sites with simultaneous ARP technique and installation of SSA seem to be very limited.

Digitalized CAD/CAM protocol for the fabrication of customized sealing socket healing abutments in immediate implants in molar sites.

Immediate implant placement in molar sites has the potential to improve patient treatment experience by reducing overall treatment time and the number of appointments. However, primary closure remains a technical challenge. AIM: The objective of this case series was to assess the final clinical outcome at the 2-year follow-up of immediate implant therapy in molar sites using a digitally fabricated sealing socket abutment (SSA) at the time of extraction. MATERIALS AND METHODS: This case series included 29 patients who received immediate implant placement in molar sites. A digital impression was taken at the time of placement, and a chairside CAD/CAM healing abutment was fabricated and delivered in situ to close the alveolar socket. Clinical assessments were reported with a minimum of 2 years of follow-up. RESULTS: All patients reported uneventful postoperative recovery after 1 week of healing. No implant failures were observed. The assessment by an experienced clinician showed healthy and stable periimplant tissue. CONCLUSION: Based on the results of this study, the combination of an immediate implant placement protocol and a customized SSA seems to be a viable treatment alternative, although this needs to be confirmed by future prospective randomized studies.

Improving oral implant osseointegration in a murine model via Wnt signal amplification.

AIM: To determine the key biological events occurring during implant failure and then we use this knowledge to develop new biology-based strategies that improve osseointegration. MATERIALS AND METHODS: Wild-type and Axin2(LacZ/LacZ) adult male mice underwent oral implant placement, with and without primary stability. Peri-implant tissues were evaluated using histology, alkaline phosphatase (ALP) activity, tartrate resistant acid phosphatase (TRAP) activity and TUNEL staining. In addition, mineralization sites, collagenous matrix organization and the expression of bone markers in the peri-implant tissues were assessed. RESULTS: Maxillary implants lacking primary stability show histological evidence of persistent fibrous encapsulation and mobility, which recapitulates the clinical problems of implant failure. Despite histological and molecular evidence of fibrous encapsulation, osteoblasts in the gap interface exhibit robust ALP activity. This mineralization activity is counteracted by osteoclast activity that resorbs any new bony matrix and consequently, the fibrous encapsulation remains. Using a genetic mouse model, we show that implants lacking primary stability undergo osseointegration, provided that Wnt signalling is amplified. CONCLUSIONS: In a mouse model of oral implant failure caused by a lack of primary stability, we find evidence of active mineralization. This mineralization, however, is outpaced by robust bone resorption, which culminates in persistent fibrous encapsulation of the implant. Fibrous encapsulation can be prevented and osseointegration assured if Wnt signalling is elevated at the time of implant placement.

Wnt/ß-catenin signaling and Msx1 promote outgrowth of the maxillary prominences.

Facial morphogenesis requires a series of precisely orchestrated molecular events to promote the growth and fusion of the facial prominences. Cleft palate (CP) results from perturbations in this process. The transcriptional repressor Msx1 is a key participant in these molecular events, as demonstrated by the palatal clefting phenotype observed in Msx1(-/-) embryos. Here, we exploited the high degree of conservation that exists in the gene regulatory networks that shape the faces of birds and mice, to gain a deeper understanding of Msx1 function in CP. Histomorphometric analyses indicated that facial development was disrupted as early as E12.5 in Msx1(-/-) embryos, long before the palatal shelves have formed. By mapping the expression domain of Msx1 in E11.5 and E12.5 embryos, we found the structures most affected by loss of Msx1 function were the maxillary prominences. Maxillary growth retardation was accompanied by perturbations in angiogenesis that preceded the CP phenotype. Experimental chick manipulations and in vitro assays showed that the regulation of Msx1 expression by the Wnt/ß-catenin pathway is highly specific. Our data in mice and chicks indicate a conserved role for Msx1 in regulating the outgrowth of the maxillary prominences, and underscore how imbalances in Msx1 function can lead of growth disruptions that manifest as CP.

The acceleration of implant osseointegration by liposomal Wnt3a.

The strength of a Wnt-based strategy for tissue regeneration lies in the central role that Wnts play in healing. Tissue injury triggers local Wnt activation at the site of damage, and this Wnt signal is required for the repair and/or regeneration of almost all tissues including bone, neural tissues, myocardium, and epidermis. We developed a biologically based approach to create a transient elevation in Wnt signaling in peri-implant tissues, and in doing so, accelerated bone formation around the implant. Our subsequent molecular and cellular analyses provide mechanistic insights into the basis for this pro-osteogenic effect. Given the essential role of Wnt signaling in bone formation, this protein-based approach may have widespread application in implant osseointegration.

Relationship between sponsorship and failure rate of dental implants: a systematic approach.

BACKGROUND: The number of dental implant treatments increases annually. Dental implants are manufactured by competing companies. Systematic reviews and meta-analysis have shown a clear association between pharmaceutical industry funding of clinical trials and pro-industry results. So far, the impact of industry sponsorship on the outcomes and conclusions of dental implant clinical trials has never been explored. The aim of the present study was to examine financial sponsorship of dental implant trials, and to evaluate whether research funding sources may affect the annual failure rate. METHODS AND FINDINGS: A systematic approach was used to identify systematic reviews published between January 1993 and December 2008 that specifically deal with the length of survival of dental implants. Primary articles were extracted from these reviews. The failure rate of the dental implants included in the trials was calculated. Data on publication year, Impact Factor, prosthetic design, periodontal status reporting, number of dental implants included in the trials, methodological quality of the studies, presence of a statistical advisor, and financial sponsorship were extracted by two independent reviewers (kappa = 0.90; CI(95%) [0.77-1.00]). Univariate quasi-Poisson regression models and multivariate analysis were used to identify variables that were significantly associated with failure rates. Five systematic reviews were identified from which 41 analyzable trials were extracted. The mean annual failure rate estimate was 1.09%.(CI(95%) [0.84-1.42]). The funding source was not reported in 63% of the trials (26/41). Sixty-six percent of the trials were considered as having a risk of bias (27/41). Given study age, both industry associated (OR = 0.21; CI(95%) [0.12-0.38]) and unknown funding source trials (OR = 0.33; (CI(95%) [0.21-0.51]) had a lower annual failure rates compared with non-industry associated trials. A conflict of interest statement was disclosed in 2 trials. CONCLUSIONS: When controlling for other factors, the probability of annual failure for industry associated trials is significantly lower compared with non-industry associated trials. This bias may have significant implications on tooth extraction decision making, research on tooth preservation, and governmental health care policies.