Effect of Smoke Exposure on Gene Expression in Bone Healing around Implants Coated with Nanohydroxyapatite

This study evaluated the effect of smoke exposure on the expression of genes related to bone metabolism in implants coated with nanohydroxyapatite (NHA). A total of 36 rats were exposed to cigarette smoke for 60 days. The animals were allocated into three groups: machined implants (MAC), dual acid-etched implants (DAE), and NHA-coated implants (NHA). Implants were installed in the left tibia of the rats after 30 days of smoke exposure. The implants were retrieved 7 and 30 days after implantation, and the adjacent bone analyzed using a real-time polymerase chain reaction for gene expression of alkaline phosphatase (ALP), osteopontin (OPN), receptor activator of the nuclear factor kappa ligand (RANKL), osteoprotegerin (OPG), the RANKL/OPG ratio, osteocalcin (OCN) and runt-related transcription factor 2 (Runx2). After 7 days, Runx2, OPN and OPG expression demonstrated significantly higher levels for the NHA surface treatment relative to DAE and MAC surfaces. NHA presented the lowest RANKL and RANKL/OPG levels. After 30 days, NHA-coated implants showed significantly higher levels of Runx2, ALP, OPN, OPG, OC, RANKL and RANKL/OPG relative to DAE and MAC implants. The results indicated a greater osteogenic and high osteoclastic activity around NHA implants, in comparison to DAE and MAC implants

Effect of cetylpyridinium chloride with xylitol on the formation of biofilm and development of gingivitis

Aim: To assess the effect of the combination of cetylpyridinium chloride and xylitol on the formation of dental biofilm and development of experimental gingivitis. Methods: A crossover, double-blind, placebo-controlled study was conducted and divided into two phases of 21 days each with a time interval of 10 days between them. A modified experimental gingivitis model was used and 31 volunteers were randomly divided into 2 groups. The volunteers performed daily mouthwashes twice a day with the test solution containing cetylpyridinium combined with xylitol or a placebo solution. On day 0 and day 21 of each phase the Plaque Index (PI) and Gingival Index (GI) of each volunteer were measured. During this phase, the volunteers brushed their teeth with standard toothbrushes and dentifrice, protecting the third quadrant with a toothshield. After brushing, the toothshield was removed and the mouthwash was used. Results: The PI values observed in the Test Group at baseline and on day 21 were 0 (0.00 – 0.03) and 0 (0.22-0.48) respectively, and in Control Group 0 (0.00 – 0.03) and 1 (0.45 – 0.81) (inter-group analysis - McNemar test, p<0.05). For GI, the values obtained in the Test Group were 0 (0.00 – 0.03) and 1 (0.48 – 0.71), at baseline and day 21 and in Control Group 0 (0.00 – 0.03) and 1 (0.58 – 0.84) (inter-group analysis - McNemar test, p>0.05). Conclusions: The test solution had a positive effect on dental biofilm control. However, it was not capable of preventing the development of experimental gingivitis

Effect of cetylpyridinium chloride with xylitol on the formation of biofilm and development of gingivitis

assess the effect of the combination of cetylpyridinium chloride and xylitol on the formation of dental biofilm and development of experimental gingivitis. Methods: A crossover, double-blind, placebo-controlled study was conducted and divided into two phases of 21 days each with a time interval of 10 days between them. A modified experimental gingivitis model was used and 31 volunteers were randomly divided into 2 groups. The volunteers performed daily mouthwashes twice a day with the test solution containing cetylpyridinium combined with xylitol or a placebo solution. On day 0 and day 21 of each phase the Plaque Index (PI) and Gingival Index (GI) of each volunteer were measured. During this phase, the volunteers brushed their teeth with standard toothbrushes and dentifrice, protecting the third quadrant with a toothshield. After brushing, the toothshield was removed and the mouthwash was used. Results: The PI values observed in the Test Group at baseline and on day 21 were 0 (0.00 0.03) and 0 (0.22-0.48) respectively, and in Control Group 0 (0.00 0.03) and 1 (0.45 0.81) (inter-group analysis - McNemar test, p0.05). Conclusions: The test solution had a positive effect on dental biofilm control. However, it was not capable of preventing the development of experimental gingivitis

In vivo osseointegration evaluation of implants coated with nanostructured hydroxyapatite in low density bone.

ObjectiveThis in vivo study, aimed to biomechanically, histomorphometrically and histologically evaluate an implant surface coated with nanostructured hydroxyapatite using the wet chemical process (biomimetic deposition of calcium phosphate coating) when compared to a dual acid-etching surface.Material and methodsTen sheep (2-4 years old) received 20 implants, 10 with nanostructured hydroxyapatite coating (HAnano), and 10 with dual acid-etching surface (DAA). The surfaces were characterized with scanning electron microscopy and energy dispersive spectroscopy; insertion torque values and resonance frequency analysis were measured to evaluate the primary stability of the implants. Bone-implant contact (BIC) and bone area fraction occupancy (BAFo) were evaluated 14 and 28 days after implant installation.ResultsThe HAnano and DAA groups showed no significant difference in insertion torque and resonance frequency analysis. The BIC and BAFo values increased significantly (pConclusionThe results suggest that the HAnano surface favors bone formation when compared to the DAA surface after 28 days in low-density bone in sheep

Evaluation of Bone Response to a Nano HA Implant Surface on Sinus Lifting Procedures: Study in Rabbits

The aim of this study was to evaluate the bone response to two different implant surfaces on sinus lift procedures in rabbits. Bilateral sinus lifting with inorganic bovine bone associated with collagen membrane and immediate implantation were performed in 16 rabbits. Custom mini-implants were randomly installed in the prepared sites: one side received a double acid-etched (DAE) surface and the other a nano-hydroxyapatite (NHA) surface. The animals were euthanized 30 and 60 days after surgery, and biopsies were collected for microtomographic and histomorphometric analysis. After 30 days, no intra- and inter-group statistical differences were observed in microtomographic analysis, while at 60 days, bone analysis showed statistically significant differences between groups (p &lt; 0.05) for all the evaluated parameters. Histomorphometric analysis showed, after 30 days, mean % of Bone-to-Implant Contact (BIC) for DAE and NHA of 31.70 &plusmn; 10.42% vs. 40.60 &plusmn; 10.22% (p &gt; 0.05), respectively; for % of Bone Area Fraction Occupancy (BAFO), mean values were 45.43 &plusmn; 3.597% for DAE and 57.04 &plusmn; 5.537% for NHA (p &lt; 0.05). After 60 days, mean %BIC and %BAFO for DAE and NHA implants were statistically significant (p &lt; 0.05). The NHA surface showed superior biological features compared to the DAE treatment, promoting higher bone formation around the implants in an experimental model of bone repair in a grafted area

Quantitative characteristics of carcass and meat quality of ¾ Boer + ¼ Saanen and Saanen goat kids fed diets with dry yeast Características quantitativas de carcaça e de qualidade da carne de cabritos ¾ Boer + ¼ Saanen e Saanen alimentados com rações contendo levedura seca

Twenty-seven carcasses of non-castrated confined goat kids, (18 ¾ Boer + ¼ Saanen and nine Saanen) with slaughtered weight of 30.1 ± 0.27 kg were used to evaluate quantitative characteristics of the carcass and qualitative characteristics of the loin and shoulder. The animals were distributed in a completely randomized design in a 2 × 3 factorial arrangement (breed group × diet). The diets consisted of inclusion of dry yeast, as follows: soybean meal, soybean meal + dried yeast or dried yeast. The other ingredients of the diets were oat hay (30% DM), ground corn and mineral mixture. Hot carcass weight, cold carcass weight, weight loss by cooling, true carcass yield and carcass compactness index were not influenced by the inclusion of dry yeast nor by racial group. Saanen goats presented the highest carcass commercial yield of carcass, but they needed 15 days more to reach the slaughter weight. The cut yields were not affected, but a significant interaction for shoulder yield occurred. Dry yeast and breed group did not influence the measurements of the loin, the muscle:bone ratio, the cooking losses, the shear force and composition. There was a significant interaction between the inclusion of dry yeast in the diets and the breed group for the muscle proportion on loin, which was higher in the ¾ Boer + ¼ Saanen group. For the shoulder, inclusion of dry yeast and breed group did not alter the proportions of muscle, fat, protein and ash. However, in Saanen goats, the proportion of bone and moisture content were higher and total lipid content was lower. The ¾ Boer + ¼ Saanen groups showed higher precocity. Dry yeast is an alternative protein source that can be included in diets for goat kids.<br>Foram utilizadas 27 carcaças de cabritos machos não-castrados, confinados, sendo 18 ¾ Boer + ¼ Saanen e nove Saanen com peso de abate de 30,1 ± 0,27 kg, para avaliar as características quantitativas da carcaça e qualitativas do lombo e da paleta. Os animais foram distribuídos em delineamento inteiramente casualizado em arranjo fatorial 2 × 3 (grupo racial × rações). As rações foram constituídas pela inclusão de levedura seca, sendo: farelo de soja, farelo de soja + levedura seca ou levedura seca. Os demais ingredientes das rações foram o feno de aveia (30% da MS), milho moído e mistura mineral. Os pesos de carcaça quente e de carcaça fria, as perdas de peso por resfriamento, o rendimento verdadeiro de carcaça e o índice de compacidade de carcaça não foram influenciados pela inclusão da levedura seca nem pelo grupo racial. O grupo Saanen apresentou maior rendimento comercial de carcaça, porém 15 dias a mais de idade para atingir o peso de abate. Os rendimentos de cortes não foram influenciados, porém ocorreu interação significativa para rendimento de paleta. A levedura seca e o grupo racial não influenciaram as medidas do lombo, a razão músculo:osso, as perdas de peso por cocção, a força de cisalhamento e a composição centesimal. Houve interação significativa entre a inclusão da levedura seca nas rações e o grupo racial para a proporção de músculo do lombo, que foi maior no grupo ¾ Boer + ¼ Saanen. Na paleta, a inclusão de levedura seca e o grupo racial não alteraram as proporções de músculo, gordura, teor de proteína e cinzas. Entretanto, no grupo Saanen, a proporção de osso e o teor de umidade foram maiores e teor de lipídios totais menor. O grupo ¾ Boer + ¼ Saanen apresentou maior precocidade. A levedura seca é uma fonte proteica alternativa que pode ser incluída em rações para cabritos