Comparative therapeutic use of Risedronate and Calcarea phosphorica - Allopathy versus homeopathy - In bone repair in castrated rats

Osteoporosis, a disease characterized by progressive bone loss, has been the target of several studies in the past few years. It results in a much higher risk for fractures and might cause slower bone lesion healing. The aim of this work was to study the effects of Risedronate (allopathic medicine) and Calcarea phosphorica 6CH (homeopathic medicine) on the repair of bone lesions in male rats with osteoporosis induced by castration. Eighty-four three-month-old rats were used divided into four groups of twenty-one animals each. Three groups where castrated and one group was submitted to Sham surgery. One month later, cortical lesions were made in all animals' tibiae and, after one day, the different experimental treatments began according to the following groups: CR - castrated/Risedronate (1 mg/kg/day); CCp - castrated/ Calcarea phosphorica 6CH (3 drops/day); CP - castrated/placebo and SP - Sham/placebo. The animals were sacrificed at seven, fourteen and twenty-eight days after the beginning of the treatments and had their tibiae removed. Digital radiographs of the tibiae were taken and analyzed in order to evaluate the optical density of the defect area. Then, they were decalcified and processed for histological and histomorphometrical analysis. The data were submitted to ANOVA, and to the Tukey and Dunnett tests (5%). The allopathic and homeopathic treatments led to different bone formation as regards remodeling and maturation aspects. Further research is necessary to access the resistance and quality of the newly formed bone.

Effect of 10% carbamide peroxide dental bleaching on microhardness of filled and unfilled sealant materials

Purpose: The purpose of this study was to quantitatively evaluate the effect of 10% carbamide peroxide on the microhardness of pit and fissure sealant materials. Methods: Fluroshield, Vitroseal Alfa, and one unfilled (Clinpro) sealants were placed in Teflon matrices (4 mm in diameter by 2 mm in height) and polymerized for 40 seconds. A total of 20 specimens were prepared for each material, in which half were assigned as the control group (stored in artificial saliva and no bleaching treatment). For the remaining half, Clarigel Gold bleaching agent (10% carbamide peroxide) was placed over the specimen surface for 4 hours/day during 4 weeks. When specimens were not under bleaching treatment, they were kept in artificial saliva. Afterwards, specimens were subjected to Knoop microhardness testing using a 25-g load for 5 seconds. Five measurements were made on the sealants' surfaces and then calculated in Knoop hardness values. The data were statistically analyzed by two-way analysis of variance and Tukey's tests with a 5% confidence level. Results: The results of this in vitro study showed that the application of a carbamide peroxide-based bleaching material significantly affected the microhardness values of filled sealant materials. The bleaching agent did not affect the microhardness of the unfilled sealant. CLINICAL SIGNIFICANCE: The results of this in vitro study suggest that the bleaching agents altered the surface hardness of filled sealant restorative materials. This could possibly lead to increased wear and surface roughness. © 2006, Copyright the authors.

Dispersed lipid liquid crystalline phases stabilized by a hydrophobically modified cellulose

Aqueous dispersions of monoolein (MO) with a commercial hydrophobically modified ethyl hydroxyethyl cellulose ether (HMEHEC) have been investigated with respect to the morphologies of the liquid crystalline nanoparticles. Only very low proportions of HMEHEC are accepted in the cubic and lamellar phases of the monoolein-water system. Due to the broad variation of composition and size of the commercial polymer, no other single-phase regions were found in the quasi-ternary system. Interactions of MO with different fractions of the HMEHEC sample induced the formation of lamellar and reversed hexagonal phases, identified from SAXD, polarization microscopy, and cryogenic TEM examinations. In excess water (more than 90 wt %) coarse dispersions are formed more or less spontaneously, containing particles of cubic phase from a size visible by the naked eye to small particles observed by cryoTEM. At high polymer/MO ratios, vesicles were frequently observed, often oligo-lamellar with inter-lamellar connections. After homogenization of the coarse dispersions in a microfluidizer, the large particles disappeared, apparently replaced by smaller cubic particles, often with vesicular attachments on the surfaces, and by vesicles or vesicular particles with a disordered interior. At the largest polymer contents no proper cubic particles were found directly after homogenization but mainly single-walled defected vesicles with a peculiar edgy appearance. During storage for 2 weeks, the dispersed particles changed toward more well-shaped cubic particles, even in dispersions with the highest polymer contents. In some of the samples with low polymer/MO ratio, dispersed particles of the reversed hexagonal type were found. A few of the homogenized samples were freeze-dried and rehydrated. Particles of essentially the same types, but with a less well-developed cubic character, were found after this treatment. © 2007 American Chemical Society.

Periapical tissue healing after post space preparation with or without use of a protection plug and root canal exposure to the oral environment. Study in dogs

The purpose of this study was to evaluate the influence of coronal leakage on the healing of dogs' periapical tissues after root canal filling, post space preparation and protection or not with a temporary sealer plug. Forty root canals of dogs' teeth were instrumented and filled by the lateral condensation technique with gutta-percha points and Endomethasone or CRCS sealers. After post space preparation, the remaining filling material was protected or not with a plug of temporary Coltosol sealer and exposed to the oral environment for 90 days. Thereafter, the animals were sacrificed and the specimens were removed and prepared for histomorphological and histobacteriological analysis. The findings revealed 35% of microbial leakage in the groups without plugs and 15% of leakage in the groups with plugs. Statistical analysis showed that the use of a Coltosol plug improved significantly the histomorphological results regardless of the type of root canal sealer (p=0.05) and that CRCS and Endomethasone sealers showed similar results (p>0.05).

Effectiveness of six different disinfectants on removing five microbial species and effects on the topographic characteristics of acrylic resin

Purpose: The aim of this study was to evaluate the effectiveness of disinfectant solutions (1% sodium hypochlorite, 2% chlorhexidine digluconate, 2% glutaraldehyde, 100% vinegar, tabs of sodium perborate-based denture cleanser, and 3.8% sodium perborate) in the disinfection of acrylic resin specimens (n = 10/group) contaminated in vitro by Candida albicans, Streptococcus mutans, S. aureus, Escherichia coli, or Bacillus subtilis as measured by residual colony-forming unit (CFU). In a separate experiment, acrylic resin was treated with disinfectants to monitor potential effects on surface roughness, Ra (μm), which might facilitate microbial adherence. Materials and Methods: Three hundred fifty acrylic resin specimens contaminated in vitro with 1×10 6 cells/ml suspensions of standard strains of the cited microorganisms were immersed in the disinfectants for 10 minutes; the control group was not submitted to any disinfection process. Final counts of microorganisms per ml were performed by plating method for the evaluation of microbial level reduction. Results were compared statistically by ANOVA and Tukey's test (p ≤ 0.05). In a parallel study aiming to evaluate the effect of the tested disinfectant on resin surface, 60 specimens were analyzed in a digital rugosimeter before and after ten cycles of 10-minute immersion in the disinfectants. Measurements of superficial roughness, Ra (μm), were compared statistically by paired t-test (p ≤ 0.05). Results: The results showed that 1% sodium hypochlorite, 2% glutaraldehyde, and 2% chlorhexidine digluconate were most effective against the analyzed microorganisms, followed by 100% vinegar, 3.8% sodium perborate, and tabs of sodium perborate-based denture cleanser. Superficial roughness of the specimens was higher after disinfection cycles with 3.8% sodium perborate (p = 0.03) and lower after the cycles with 2% chlorhexidine digluconate (p = 0.04). Conclusion: Within the limits of this experiment, it could be concluded that 1% sodium hypochlorite, 2% glutaraldehyde, 2% chlorexidine, 100% vinegar, and 3.8% sodium perborate are valid alternatives for the disinfection of acrylic resin. © 2008 by The American College of Prosthodontists.

LH surge in Nelore cows (Bos indicus), after induced estrus or after ovarian superestimulation

Considering that there is limited information about the preovulatory LH surge in Zebu cattle (Bos indicus), the purpose of the present work was to assess the LH surge in Nelore cows during the estrous cycle and after ovarian superestimulation of ovarian follicular development with FSH. This information is particularly important to improve superovulatory protocols associated with fixed-time artificial insemination. Nelore cows (n = 12) had their estrus synchronized with an intravaginal device containing progesterone (CIDR-B ®) associated with estradiol benzoate administration (EB, 2.5 mg, i.m., Day 0). Eight days later all animals were treated with PGF2α (Day 8) in the morning (8:00 h) and at night, when CIDR devices were removed (20:00 h). Starting 38 h after the first PGF2α injection, blood sampling and ovarian ultrasonography took place every 4 h, during 37 consecutive hours. Frequent handling may have resulted in a stress-induced suppression of LH secretion resulting in only 3 of 12 cows having ovulations at 46.7 ± 4.9 and 72.3 ± 3.8 h, respectively, after removal of CIDR-B. Thirty days later, the same animals received the described hormonal treatment associated with FSH (Folltropin ®, total dose = 200 mg) administered twice a day, during 4 consecutive days, starting on Day 5. Thirty-six hours after the first injection of PGF2α, to minimize stress, only seven blood samples were collected at 4 h interval each, and ultrasonography was performed every 12 h until ovulation. In 11 of 12 cows (92%) the LH surge and ovulation were observed 34.6 ± 1.6 and 59.5 ± 1.9 h, respectively, after removal of progesterone source. The maximum values for LH in those animals were 19.0 ± 2.6 ng/ml (mean ± S.E.M.). It is concluded that, in Nelore cows submitted to a ovarian superstimulation protocol, the LH surge occurs approximately 35 h after removal of intravaginal device containing progesterone, and approximately 12 h before the LH surge observed after an induced estrus without ovarian superstimulation. © 2008 Elsevier B.V. All rights reserved.

Immunohistochemical expression of HLA-DR in the conjunctiva of patients under topical prostaglandin analogs treatment

PURPOSE: Subclinical inflammation may be observed in patients using topical antiglaucomatous drugs. The objective of this study was to investigate inflammation in conjunctiva of glaucoma patients using prostaglandin analogs, by the detection of an immunogenetic marker (HLA-DR) and compare the effect of 3 different drugs: latanoprost, bimatoprost, and travoprost in the induction of this inflammation. SUBJECTS AND METHODS: Thirty-three patients with primary open-angle glaucoma were evaluated without and with prostaglandin analogs topical therapy. Imprints of conjunctival cells were obtained, fixed on glass slides, and prepared for immunohistochemical analysis. RESULTS: Before the use of prostaglandin analogs, 4 of the 33 patients evaluated presented expression of HLA-DR in the conjunctiva (mild). After 1 month on prostaglandin analog treatment, all but 1 patient presented HLA-DR staining. HLA-DR expression of these 32 patients was scored as mild (19 patients), medium (11 patients), or intense (2 patients). The differences were statistically significant both when the presence and the increased expression of HLA-DR were considered (P<0.001). When the 3 different groups were analyzed (latanoprost, bimatoprost, and travoprost) no statistically significant difference was found (P=0.27). CONCLUSIONS: The use of prostaglandin analogs eye drops provokes a subclinical inflammatory reaction, observed by HLA-DR expression, even after a short period of treatment, independently of the class of the prostaglandin analogs used. © 2009 Lippincott Williams & Wilkins, Inc.

Sistemas biodegradáveis contendo acetato de prednisolona para administração orbitária

Purpose: The present study aimed to evaluate an injectable extended-release formulation of prednisolone acetate (PA) for orbital administration. Methods: Microspheres (MEs) of poly-ε-caprolactone (PCL) containing PA were developed by the method of solvent evaporation. The MEs obtained were characterized by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), encapsulation efficiency and in vitro release profile. The in vivo release profile was evaluated in rabbits after periocular injection of an aqueous suspension of MEs. The local biocompatibility of the system was verified by histopathologic analysis of the deployment region. Results: After MEs preparation, morphological analysis by SEM showed the feasibility of the employed method. The content of PA encapsulated was 43 ± 7% and can be considered as satisfactory. The system characterization by DSC technique, in addition to confirm the system stability, did not indicate the existence of interaction between the drug and the polymer. The in vitro release study showed the prolonged-release features of the developed system. Preliminary in vivo study showed the absence of local toxicity and confirmed the prolonged release profile of PA from MEs, suggesting the viability of the developed system for the treatment of orbital inflammatory diseases. Conclusion: The results obtained in this work are relevant and accredit the system developed as a possible alternative to the treatment of inflammatory orbitopathy.

Influence of preventive dental treatment on mutans streptococci counts in patients undergoing head and neck radiotherapy

The aim of this study was to evaluate the influence of chlorhexidine gluconate, sodium fluoride and sodium iodine on mutans streptococci counts in saliva of irradiated patients. Forty-five patients were separated into three experimental groups and received chlorhexidine (0.12%), sodium fluoride (0.5%) or sodium iodine (2%), which were used daily during radiotherapy and for 6 months after the conclusion of the treatment. In addition, a fourth group, composed by 15 additional oncologic patients, who did not receive the mouthwash or initial dental treatment, constituted the control group. Clinical evaluations were performed in the first visit to dental clinic, after initial dental treatment, immediately before radiotherapy, after radiotherapy and 30, 60, 90 days and 6 months after the conclusion of radiotherapy. After clinical examinations, samples of saliva were inoculated on SB20 selective agar and incubated under anaerobiosis, at 37oC for 48 h. Total mutans streptococci counts were also evaluated by using real-time PCR, through TaqMan system, with specific primers and probes for S. mutans and S. sobrinus. All preventive protocols were able to reduce significantly mutans streptococci counts, but chlorhexidine gluconate was the most effective, and induced a significant amelioration of radiotherapy side effects, such as mucositis and candidosis. These results highlights the importance of the initial dental treatment for patients who will be subjected to radiotherapy for head and neck cancer treatment.

Evaluation of alternative methods for the disinfection of toothbrushes

The aim of this study was to evaluate alternative methods for the disinfection of toothbrushes considering that most of the previously proposed methods are expensive and cannot be easily implemented. Two-hundred toothbrushes with standardized dimensions and bristles were included in the study. The toothbrushes were divided into 20 experimental groups (n=10), according to microorganism considered and chemical agent used. The toothbrushes were contaminated in vitro by standardized suspensions of Streptococcus mutans, Streptococcus pyogenes, Staphylococcus aureus or Candida albicans. The following disinfectants were tested: 0.12% chlorhexidine digluconate, 50% white vinegar, a triclosan-containing dentifrice solution, and a perborate-based tablet solution. The disinfection method was immersion in the disinfectant for 10min. After the disinfection procedure, the number of remaining microbial cells was evaluated. The values of cfu/toothbrush of each group of microorganism after disinfection were compared by Kruskal-Wallis ANOVA and Dunn's test for multiple comparisons (5%). The chlorhexidine digluconate solution was the most effective disinfectant. The triclosan-based dentifrice solution promoted a significant reduction of all microorganisms' counts in relation to the control group. As to the disinfection with 50% vinegar, a significant reduction was observed for all the microorganisms, except for C. albicans. The sodium perborate solution was the less effective against the tested microorganisms. Solutions based on triclosan-containing dentifrice may be considered effective, nontoxic, cost-effective, and an easily applicable alternative for the disinfection of toothbrushes. The vinegar solution reduced the presence of S. aureus, S. mutans and S. pyogenes on toothbrushes.

Antimicrobial analysis of chlorhexidine gel and intracanal medicaments against microorganisms inoculated in root canals

The aim of this paper was to evaluate the antimicrobial activity of 2% chlorhexidine gel (CLX) associated with various intracanal medicaments against Candida albicans and Enterococcus faecalis inoculated in root canals. Thirty six human single-rooted teeth were contaminated with C.albicans and E.faecalis. The canals were instrumented using 2% CLX gel and were divided into three groups according to the intracanal medicaments (ICM) used. Group 1: calcium hydroxide paste [Ca(OH)], Group 2: 2% chlorhexidine gel (CLX) and Group 3: 2% CLX gel + Ca(OH). The root canal collections were performed after 21 days of contamination (control collection), after instrumentation (1st collection), after 14 days of intracanal medicament (2nd collection) and 7 days after medicament removal (3rd collection). The microbiological samples were plated in culture media and incubated for 48 hours. The results were submitted to Kruskal-Wallis test (P ≤ 0.05). It was verified that the instrumentation with CLX reduced the number of CFU/ml significantly when compared with the confirmation collection (control). However, the use of the ICM was only capable to eliminate completely the microorganisms in the root canals without difference statistics between them. Although the use of 2% chlorherixidine gel reduces the number of microorganisms significantly, only the ICM calcium hydroxide and calcium hydroxide associated with chlorhexidine are able to eliminate these microorganisms completely.

Effects of five carbamide peroxide bleaching gels on composite resin microhardness.

The purpose of this study was to evaluate the effects of five home bleaching products containing 15-16% carbamide peroxide on the microhardness of microhybrid composite resin Z-250 (3M/Espe). A total of 72 specimens were fabricated in cylindrical acrylic matrices (4 x 2 mm), filled with composite resin and photo-activated for 40 seconds. They were divided in 6 study groups (n = 12), according to the bleaching product: Review (SS White), Magic Bleaching (Vigodent), Opalescence (Ultradent), Whiteness Perfect (FGM), Claridex (Biodinâmica), and a control group (not bleached). Specimens were exposed to 1 cc of bleaching gel for 6 hours daily for 2 weeks. The control group specimens were kept in artificial saliva throughout this time. All the specimens were then analyzed in a microhardness tester. Knoop hardness measurements were performed, and the results were submitted to parametric statistical analysis (analysis of variance and Tukey's test). Mean Knoop values and standard deviation were: baseline, 68.52a (4.28); control, 63.42b (7.16); Whiteness Perfect, 57.57c (1.81); Magic Bleaching, 57.22c (3.84); Opalescence, 57.03cd (4.00); Claridex, 53.64de (3.33); Review 51.45e (2.82). Identical letters mean statistical equality according to Tukey's test at the 5% significance level. The products significantly decreased Z-250 (3M/Espe) microhardness.

The effect of carbamide peroxide bleaching agents on the microhardness of dental ceramics.

This study examined the effect of 10% and 16% carbamide peroxide bleaching agents on the surface microhardness of micro-particulate feldspathic ceramics (VM7 and VM13, Vita Zahnfabrik). Forty specimens (8-mm diameter, 2-mm thickness) were divided into four groups (n=10): GI-VM7 + 10% Whiteness, G2-VM7 + 16% Whiteness, G3-VM13 + 10% and G4-VM13 + 16% Whiteness. The home-use bleaching agents were applied for 8 hours on 15 days, and the specimens were stored in distilled water at 37 degrees C. The Vickers hardness number (HV) was determined for each specimen. Data were analyzed by the Wilcoxon and Mann-Whitney tests (p < 0.05). The microhardness values before exposure were: g1-433 (57); g2-486 (22); g3-509 (28); g4-518 (24), and after exposure: G1-349 (32); G2-496 (95); G3-519 (38); G4-502 (81). G2 exhibited a higher and significant difference than GI in VM7 groups, and the effect of bleaching concentration was shown to be significant by the Mann-Whitney test. And for VM13, both the Wilcoxon and Mann-Whitney tests showed no significant differences. When using 10% carbamide peroxide, the microhardness of VM7 ceramic was affected, and there were no effect on the microhardness between VM7 and VM13 ceramics when 16% carbamide peroxide was used.

Effect of bleaching agent on dental ceramics roughness.

The aim of this study was to assess the effect of bleaching agents (10% and 16% carbamide peroxide) on the roughness of two dental ceramics in vitro, and to analyze the surface by scanning electronic microscopy (SEM). Two bleaching agents (10% and 16%/Whiteness, FGM Gel) and two microparticle feldspathic ceramics (Vita VM7 and Vita VM13) were used. Forty disks of Vita VM7 and Vita VM13 ceramic were manufactured, measuring 4 mm in diameter and 4 mm high, in accordance with the manufacturers' recommendations, and were divided into 4 groups (n = 10): (1) VM7 + Whiteness 10%; (2) VM7 + Whiteness 16%; (3) VM13 + Whiteness 10%; (4) VM13 + Whiteness 16%. The bleaching agent was applied for 8 hours a day for 15 days and during the intervals the test specimens were stored in distilled water at 37 degrees C. The roughness (Ra) of the test specimens was evaluated before and after exposure to the bleaching agents using a laser roughness meter and the topographic description was analyzed by SEM. The statistical analysis of roughness data showed significant differences in the VM7 groups, using paired t-test, p = 0.05 (VM7 + Whiteness 10%: p = 0.002; VM7 + Whiteness 16%: p = 0.001) and two-sample t-test (VM7 p = 0.047), and no significant difference was found among VM13 groups. The qualitative SEM analysis showed different degrees of surface changes. The results suggest that the roughness of the tested ceramic surfaces increased after exposure to the bleaching agents.

Neither plasma progesterone concentrations nor exogenous eCG affects rates of ovulation or pregnancy in fixed-time artificial insemination (FTAI) protocols for puberal Nellore heifers

The objective was to evaluate the effects of plasma progesterone (P4) concentrations and exogenous eCG on ovulation and pregnancy rates of pubertal Nellore heifers in fixed-time artificial insemination (FTAI) protocols. In Experiment 1 (Exp. 1), on Day 0 (7 d after ovulation), heifers (n = 15) were given 2 mg of estradiol benzoate (EB) im and randomly allocated to receive: an intravaginal progesterone-releasing device containing 0.558 g of P4 (group 0.5G, n = 4); an intravaginal device containing 1 g of P4 (group 1G, n = 4); 0.558 g of P4 and PGF2α (PGF; 150 μg d-cloprostenol, group 0.5G/PGF, n = 4); or 1 g of P4 and PGF (group 1G/PGF, n = 3). On Day 8, PGF was given to all heifers and intravaginal devices removed; 24 h later (Day 9), all heifers were given 1 mg EB im. In Exp. 2, pubertal Nellore heifers (n = 292) were treated as in Exp. 1, with FTAI on Day 10 (30 to 36 h after EB). In Exp. 3, pubertal heifers (n = 459) received the treatments described for groups 0.5G/PGF and 1G/PGF and were also given 300 IU of eCG im (groups 0.5G/PGF/eCG and 1G/PGF/eCG) at device removal (Day 8). In Exp. 1, plasma P4 concentrations were significantly higher in heifers that received 1.0 vs 0.588 g P4, and were significantly lower in heifers that received PGF on Day 0. In Exp. 2 and 3, there were no significant differences among groups in rates of ovulation (65-77%) or pregnancy (Exp. 2: 26-33%; Exp. 3: 39-43%). In Exp. 3, diameter of the dominant ovarian follicle on Day 9 was larger in heifers given 0.558 g vs 1.0 g P4 (10.3 ± 0.2 vs 9.3 ± 0.2 mm; P < 0.01). In conclusion, lesser amounts of P4 in the intravaginal device or PGF on Day 0 decreased plasma P4 from Days 1 to 8 and increased diameter of the dominant follicle on Day 9. However, neither of these nor 300 IU of eCG on Day 8 significantly increased rates of ovulation or pregnancy. © 2011.