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Objective: The objective was to assess the one year implant treatment outcome and patient‐related outcome measures (PROMs) following maxillary sinus floor augmentation (MSFA) with autogenous bone graft (ABG) from the zygomatic buttress (control) compared with 1:1 mixture of ABG and anorganic porcine bone mineral (APBM) (Test I) or biphasic bone graft material (BBGM) (Test II). Materials and Methods: Sixty healthy patients (34 females, 26 males) were randomly allocated to either control or test groups. Outcome measures included survival of suprastructures and implants, implant stability quotient, health status of peri‐implant tissue, peri‐implant marginal bone loss, frequency of complications, and PROMs using Oral Health Impact Profile‐14 combined with questionnaire assessing patient perception of peri‐implant soft tissue, prosthetic solution, implant function, and implant treatment outcome using visual analogue scale. Mean differences were expressed with standard deviation and 95% confidence interval. Level of significance was.05. Results: All suprastructures and implants were well‐functioning after one year of functional implant loading. There was no significant difference between control and test groups in any of the applied outcome measures. The implant stability significantly increased from implant placement to abutment connection within all groups (p <.001). High patient satisfaction and significant improvement in oral health‐related quality of life was also reported within all groups. Conclusion: This study demonstrates that MSFA with composite grafts containing minimal amounts of ABG reveals comparable implant treatment outcomes as compared with ABG alone, after one year of functional implant loading. Extensive ABG harvesting in conjunction with MSFA therefore seems not to be needed. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study was to evaluate whether salivary contamination during placement of implants with different surface characteristics affects osseointegration in native and in augmented bone areas. Materials and Methods: Forty eight implants with machined surface (MS) and 48 implants with moderately rough surface (RS) were tested in the calvaria of 12 sheep. At the first surgery, 64 bony critical defects were randomly created and were subsequently augmented with two materials (autogenous or bovine bone). After 5 weeks of graft healing, 8 implants were placed per sheep, in native bone and in the centre of the augmented defects. Forty eight implants were soaked with saliva before placement (contaminated group [CG]), while 48 implants were not (non‐contaminated group [NCG]). Five weeks after implant placement, bone‐to‐implant contact (BIC) and bone material area fraction occupancy (BMAFO) were calculated histomorphometrically. Results: Saliva contamination showed a significant negative effect (p =.000) on BIC, especially in augmented areas. RS showed significant positive effect on BIC, compared to MS (p =.000), while there were no significant differences for different bone conditions (p =.103). For BMAFO, the contamination showed a significantly negative affect (p =.000), while there were no significant differences for surface characteristics (p =.322) and for bone condition (p =.538). Conclusion: Saliva contamination during dental implant placement has a negative effect on osseointegration in augmented areas. Moderately rough surface has a possible advantage in the aspect of initial bone to implant contact. However, it seems to be advisable to avoid saliva contamination especially for implants placed in augmented bone areas. [ABSTRACT FROM AUTHOR]

The vasodilator-stimulated phosphoprotein (VASP) is associated with actin filaments and focal adhesions, which form the interface between the cytoskeleton and the extracellular matrix. VASP is phosphorylated by both the cAMP- and cGMP-dependent protein kinases in a variety of cells, including platelets and smooth muscle cells. Since both the cAMP and cGMP signalling cascades relax smooth muscle and inhibit platelet activation, it was speculated that VASP mediates these effects by modulating actin filament dynamics and integrin activation. To study the physiological relevance of VASP in these processes, we inactivated the VASP gene in mice. Adult VASP-deficient mice had normal agonist-induced contraction, and normal cAMP- and cGMP-dependent relaxation of intestinal and vascular smooth muscle. In contrast, cAMP- and cGMP-mediated inhibition of platelet aggregation was significantly reduced in the absence of VASP. Other cAMP- and cGMP- dependent effects in platelets, such as inhibition of agonist-induced increases in cytosolic calcium concentrations and granule secretion, were not dependent on the presence of VASP. Our data show that two different cyclic, nucleotide-dependent mechanisms are operating during platelet activation: a VASP-independent mechanism for inhibition of calcium mobilization and granule release and a VASP-dependent mechanism for inhibition of platelet aggregation which may involve regulation of integrin function. [ABSTRACT FROM AUTHOR]

Background: The intraosseous temperature during implant installation has never been evaluated in an in vivo controlled setup. The aims were to investigate the influence of a drilling protocol and implant surface on the intraosseous temperature during implant installation, to evaluate the influence of temperature increase on osseointegration and to calculate the heat distribution in cortical bone. Methods: Forty Brånemark implants were installed into the metatarsal bone of Finnish Dorset crossbred sheep according to two different drilling protocols (undersized/non-undersized) and two surfaces (moderately rough/turned). The intraosseous temperature was recorded, and Finite Element Model (FEM) was generated to understand the thermal behavior. Non-decalcified histology was carried out after five weeks of healing. The following osseointegration parameters were calculated: Bone-to-implant contact (BIC), Bone Area Fraction Occupancy (BAFO), and Bone Area Fraction Occupancy up to 1.5 mm (BA1.5). A multiple regression model was used to identify the influencing variables on the histomorphometric parameters. Results: The temperature was affected by the drilling protocol, while no influence was demonstrated by the implant surface. BIC was positively influenced by the undersized drilling protocol and rough surface, BAFO was negatively influenced by the temperature rise, and BA1.5 was negatively influenced by the undersized drilling protocol. FEM showed that the temperature at the implant interface might exceed the limit for bone necrosis. Conclusion: The intraosseous temperature is greatly increased by an undersized drilling protocol but not from the implant surface. The temperature increase negatively affects the bone healing in the proximity of the implant. The undersized drilling protocol for Brånemark implant systems increases the amount of bone at the interface, but it negatively impacts the bone far from the implant. [ABSTRACT FROM AUTHOR]