The aim of this study was to evaluate the discoloration effects of water, cola-based soft drink, coffee, and wine on resin composites used in restorative dentistry and the possibility of removing the stain with chair side manual polishing. The A2 shade of three materials was tested. Disc specimens were prepared. A spectrophotometer was used to measure the baseline CIE-Lab color parameters of each material (n=10) 24 hours after sample preparation. Samples were then immersed in a cola-based soft drink, coffee, or wine for 1 hour every day, for 30 days. For the remaining hours, the specimens were stored in distilled water. In the control group, the specimens were immersed in water for the whole period. The color differences (ΔE) were calculated after 7 and 30 days of storage, and after polishing with coarse Sof-Lex discs, and analyzed by two-way ANOVA with repeated measures and Tukey's HSD test (α=0.05). Luna presented higher ΔE values (3.41)a followed by Durafill (2.82)b and Herculite (2.24)c. For the drink solutions, ΔE values were higher for wine (4.40)a followed by coffee (2.59)b and for cola-based soft drink (2.23)c and water (2.13)c which were statistically similar. For time, ΔE values were higher for 30 days (3.97)a and then for 7 days (2.48)b and after polishing (2.04)c. The results indicate that color stability is material dependent. The types of drinks that patients consume also influence the color stability of restorative materials.

Background Leukocyte‐platelet‐rich plasma (L‐PRP) is considered an important source of growth factors, especially Transforming growth factor β 1 (TGF‐β1), which modulates the proliferation and regulation of mesenchymal cells, and also exerts an influence on the hematopoiesis, osteogenesis, and adipogenesis in bone microenvironment. Thus, the aim of this study was to evaluate the effect of L‐PRP on the calvarial bone repair and compare its results on the presence of TGF‐β1, CD34, CD45, bone morphogenetic protein 2 (BMP2), BMPR1B, and Runx2 proteins detected by immunohistochemistry. Material and Methods Four bone defects were created on the calvaria of 23 rabbits. The defects were treated with autograft, L‐PRP alone, and L‐PRP mixed with autograft. The animals were euthanized at 2, 4, and 6 weeks post‐surgery. Results Unlike autograft and sham groups, the defects treated with L‐PRP demonstrated significant positivity to TGF‐β1, while the BMP2 was scarce. These results coincided with the lower bone matrix deposited and larger medullary area, which were composed of fibrosis, when treated with only L‐PRP, or intense adiposity on defects filled with L‐PRP mixed with autograft. The fibrosis that occurred was associated with a minor percentage of osteoproteins, intense presence of CD34+ CD45− cells, and significant expression of TGF‐β1 in all time periods analyzed. The adiposity occurred from the major presence of osteoprogenitor BMPR1B + Runx2+ cells simultaneously to BMP2− TGF‐β1+ and CD34+ CD45+/− expressions predominantly on the earlier period. Conclusion From this study, it can be concluded that the L‐PRP used alone or mixed to autograft hindered the osteoneogenesis due to suppression of immunoexpression of BMP2, while the immunopositivity of TGF‐β1 was intense. When used alone, the L‐PRP induced a fibrotic condition associated with TGF‐β1 presence and lack of osteoproteins, but when L‐PRP was mixed to autograft, it induced the presence of the osteolineage cells (BMPR1B + Runx2+), but also inhibited the terminal osteoblastic maturation associated with the lack of BMP2 and the presence of TGF‐β1+, a fact that contributed to cellular transdifferentiation into fat cells.

No abstract

Ameloblastoma is an aggressive odontogenic tumor which typically occurs between third and fourth decade of life that often needs resective approach. Immediate reconstruction may show better results. The treatment of multicystic ameloblastoma in the mandible being a rare case that occurred in the late second decade of life, which was surgically removed along with the affected teeth with safety margins, and the region was immediately reconstructed using a vascularized graft, removed from the fibula. Its integration, in combination with osseointegrated dental implants and fixed implant-supported prostheses, restored chewing function and esthetics. After 6 years from fibular graft and 24 months of dental implants, an excellent outcome was observed, with oral health and normal functions properly restored, and the immediate reconstruction of the mandible in resective cases, associated with oral rehabilitation with dental implants, may be considered a suitable treatment option.

The aim of this paper was to evaluate through histological analysis of the tissue reaction of deproteinized bovine bone matrix (DBBM) when inserted into the site of intramuscular ectopic sheep. In this study, 16 sheep received 3 groups and these were divided into 2 experimental times: Group 1-sham group, Group 2-particulate autogenous bone and Group 3-DBBM granules. All animals underwent surgical procedures for insertion of materials in an ectopic site (muscles of the lower back and after 3 and 6 months postoperatively, the samples were evaluated by histological analysis. The results indicated that the Sham group showed dense collagen fibers and thin, characterizing fibrosis at 3 and 6 months. In the autograft group there was a significant amount of collagen deposition and decreased inflammation at 6 months postoperatively. Group of DBBM, it was noted the presence of dense connective tissue and surrounding remaining particles was observed the formation of with osteoid characteristic tissue. The DBBM demonstrated biocompatibility, osteoconductivity and small osteogenesis capacity on ectopic site.

The present study aimed to evaluate the effect of parathormone (PTH) administered directly to the implant's surface prior to insertion, using a large translational animal model. Sixty titanium implants were divided into four groups: (i) Collagen, control group, where implants were coated with Type‐I Bovine‐collagen, and three experimental groups, where implants received varying doses of PTH: (ii) 12.5, (iii) 25, and (iv) 50 μg, prior to placement. Fifteen female sheep (~2 years old, weighing ~65 kg) received four implants in an interpolated fashion in C3, C4 or C5 vertebral bodies. After 3‐, 6‐ and 12‐weeks, samples were harvested, histologically processed, qualitatively and quantitatively assessed for bone‐to‐implant contact (BIC) and bone area fraction occupancy (BAFO). BIC yielded lower values at 6‐weeks for 50 μg relative to the control group, with no significant differences, when compared to the 12.5‐ and 25‐μg. No significant differences were detected at 6‐weeks between collagen, 12.5‐ and 25‐μg groups. At 3‐ and 12‐weeks, no differences were detected for BIC among PTH groups. With respect to BAFO, no significant differences were observed between the control and experimental groups independent of PTH concentration and time in vivo. Qualitative observations at 3‐weeks indicated the presence of a more mature bone near the implant's surface with the application of PTH, however, no significant differences in new bone formation or healing patterns were observed at 6‐ and 12‐weeks. Single local application of different concentrations of PTH on titanium implant's surface did not influence the osseointegration at any time‐point evaluation in low‐density bone.

No abstract

The present study aimed to evaluate the effect of dipyridamole, an indirect adenosine 2A receptors (A2AR), on the osseointegration of titanium implants in a large, translational pre-clinical model. Sixty tapered, acid-etched titanium implants, treated with four different coatings ((i) Type I Bovine Collagen (control), (ii) 10 μM dipyridamole (DIPY), (iii) 100 μM DIPY, and (iv) 1000 μM DIPY), were inserted in the vertebral bodies of 15 female sheep (weight ~65 kg). Qualitative and quantitative analysis were performed after 3, 6, and 12 weeks in vivo to assess histological features, and percentages of bone-to-implant contact (%BIC) and bone area fraction occupancy (%BAFO). Data was analyzed using a general linear mixed model analysis with time in vivo and coating as fixed factors. Histomorphometric analysis after 3 weeks in vivo revealed higher BIC for DIPY coated implant groups (10 μM (30.42% ± 10.62), 100 μM (36.41% ± 10.62), and 1000 μM (32.46% ± 10.62)) in comparison to the control group (17.99% ± 5.82). Further, significantly higher BAFO was observed for implants augmented with 1000 μM of DIPY (43.84% ± 9.97) compared to the control group (31.89% ± 5.46). At 6 and 12 weeks, no significant differences were observed among groups. Histological analysis evidenced similar osseointegration features and an intramembranous-type healing pattern for all groups. Qualitative observation corroborated the increased presence of woven bone formation in intimate contact with the surface of the implant and within the threads at 3 weeks with increased concentrations of DIPY. Coating the implant surface with dipyridamole yielded a favorable effect with regard to BIC and BAFO at 3 weeks in vivo. These findings suggest a positive effect of DIPY on the early stages of osseointegration.