Bone regeneration in cranioplasty and clinical complications in rabbits with alloxan-induced diabetes

This research evaluated the bone repair process in surgical defects created on the parietal bones of diabetic rabbits using the guided bone regeneration technique to observe the effects of alloxan in the induction of diabetes mellitus. Twenty-four adult rabbits were divided into three study groups: control (C), diabetic (D) and diabetic associated to polytetrafluoroethylene (PTFE) membrane (D-PTFE). For diabetes induction the animals received one dose of monohydrated alloxan (90 mg/kg) by intravenous administration in the auricular or femoral vein. In group D-PTFE the membrane covered both the floor and the surface of the bone defect. In groups D and C, the bone defect was filled up with blood clot. The specimens were fixed in 10% formol and prepared for histomorphometric analysis. The results showed that the 90 mg/kg dose of monohydrate alloxan was sufficient to promote diabetes mellitus when administered in the auricular vein. Bone regeneration was slower in the diabetic group when compared with the control and diabetic-PTFE groups, but there was no significant statistical difference between the two experimental groups (D and D-PTFE). The oral and general clinical complications among the diabetics were weight loss, polyuria, polyphagia and severe chronic gingivitis.

Effects of mandibular fixed implant-supported prostheses on masticatory and swallowing functions in completely edentulous elderly individuals

Purpose: To evaluate the effect of oral rehabilitation with immediately loaded fixed implant-supported mandibular prostheses on chewing and swallowing in elderly individuals. Materials and Methods: Fifteen completely edentulous patients aged more than 60 years (10 women and rive men), wearing removable dentures in both arches, had a mandibular denture replaced by an implant-supported prosthesis. All individuals were evaluated before surgery and again 3, 6, and 18 months later with regard to mastication and swallowing conditions. Examinations entailed an interview, evaluation of tactile sensitivity of the face, and observation of food intake, masticatory type, formations of bolus, and pain during mastication. The swallowing evaluation comprised observation of clinical signs related to the oral and pharyngeal stages of swallowing, as well as the presence of oral residue. The findings of different evaluations before and 3, 6, and 18 months after the surgical-prosthetic procedure were statistically compared by analysis of variance for repeated measurements at a significance level of 5%. Results: The questionnaire revealed a reduction in complaints of masticatory and swallowing disturbances, a decreased need for liquid ingestion, and reduced choking and coughing. Clinical evaluations showed improved oral function and bolus propulsion for both solid and paste-consistency foods; pain during mastication was also resolved. Conclusion: Treatment with mandibular implant-supported dentures had positive effects on the clinical aspects of mastication and swallowing in elderly individuals.

Acute coronary syndrome associated with continuous 5-fluorouracil infusion in a patient with metastatic colorectal cancer-a case report with a discussion on this clinical dilemma

Introduction: 5-Fluorouracil (5-FU) is considered to be the backbone of colorectal cancer (CRC) systemic therapy since the great majority of recommended regimens include its administration. A clinical picture consisting of chest pain, sometimes cardiac enzyme elevation, electrocardiogram abnormalities consistent with myocardial ischemia, and normal coronary angiogram associated with 5-FU administration have been infrequently reported. The clinical dilemma is: Which chemotherapy regimen should we use in CRC patients with a previous acute coronary syndrome (ACS) associated with 5-FU? Case Report: We describe the case of a 55-year-old otherwise healthy woman with metastatic colon adenocarcinoma who presented an ACS probably secondary to arterial vasospasm while receiving continuous intravenous 5-FU infusion (mFOLFOX6 regimen). After the ACS, the patient was treated with raltitrexate plus oxaliplatin (TOMOX) and subsequently with irinotecan plus cetuximab with no other cardiac event. Conclusion: The risk of cardiotoxicity associated with 5-FU is low but real. The probable mechanism is arterial vasospasm, as suggested by our case report. Both the use of the TOMOX regimen and irinotecan plus cetuximab seems to be safe regimens to be considered in this clinical scenario. © 2009 Humana Press Inc.

Analysis of the effects of thermal cycling on the microtensile shear bond strength of a self-etching and a conventional pit and fissure sealants to dental enamel

Objective: To analyze the effects of thermal cycling on the microtensile shear bond strength of a self-etching and a conventional pit and fissure sealants to dental enamel. Material and Method: Twenty-four healthy human molars extracted for orthodontic reasons, were sectioned in the mesio-distal direction and divided into two groups (n=24) according to the sealant to be applied: GI - conventional sealant Climpro (3M/ESPE) and GII - self-etching sealant Enamel Loc (Premier Dental). The sealants were applied on flattened enamel in matrixes 1 mm in diameter, in accordance with the manufacturers' recommendations. The specimens were stored in distilled water at 37°C for 24 hours. After this, half the samples of both groups were submitted to 500 thermal cycles in 30s baths at temperatures between 5 and 55°C. Forty-eight hours after the samples were made, the microtensile shear test was performed in an Instron 4411 test machine, with a stainless steel wire with a cylindrical cross section of 0.2mm in diameter at a constant speed of 0.5mm/s. The bond strength values were submitted to ANOVA for 2 factors and the fracture patterns were examined under an optical microscope at 65X magnification. Results: Thermal cycling did not influence the bond strength of the two sealants. The conventional sealant Climpro presented a statistically higher microtensile shear bond strength (11.72MPa, 11.34MPa with and without cycling, respectively) than the self-etching sealant Enamel Loc (5.92MPa, 5.02MPa with and without cycling, respectively). Fracture pattern analysis showed the occurrence of 100% of adhesive failures for Enamel Loc, while the conventional sealant Climpro presented 95% of adhesive failures and 5% of mixed failures. Conclusion: The conventional sealant presented higher microtensile shear bond strength to dental enamel in comparison with the self-etching sealant. Thermal cycling did not affect the bond strength of the sealants used in this study. © 2011 Nova Science Publishers, Inc.

Effects of 12-week overground walking training at ventilatory threshold velocity in type 2 diabetic women

This study analyzed the effects of overground walking training at ventilatory threshold (VT) velocity on glycaemic control, body composition, physical fitness and lipid profile in DM2 women. Nineteen sedentary patients were randomly assigned to a control group (CG; n=10, 55.9±2.2 years) or a trained group (TG; n=9, 53.4±2.3 years). Both groups were subjected to anthropometric measures, a 12-h fasting blood sampling and a graded treadmill exercise test at baseline and after a 12-week period, during which TG followed a training program involving overground walking at VT velocity for 20-60min/session three times/week. Significant group×time interactions (P<0.05) in glycated hemoglobin (HbA1c), body mass, body mass index (BMI), peak oxygen uptake (VO 2peak) and exercise duration were observed as effects of training exercise, whereas intervention did not induced significant changes (P>0.05) in fasting blood glucose, submaximal fitness parameters and lipid profile. Our results suggest that overground walking training at VT velocity improves long term glycaemic control, body composition and exercise capacity, attesting for the relevance of this parameter as an effective strategy for the exercise intensity prescription in DM2 population. © 2011 Elsevier B.V.

Drug-induced gingival overgrowth: A clinical and histopathological report

Gingival overgrowth is a significant problem faced by periodontists and is particularly associated with the use of certain drugs such as nifedipine, a high-specificity calcium channel blocker used for the treatment and prophylaxis of certain cardiovascular diseases. Development of gingival overgrowth is characterized by increased collagen in gingival tissue. In general is asymptomatic, at times associated with spontaneous bleeding and ulceration and can promote aesthetic changes and compromise hygiene habits and mastication of the patient. The severity of the symptoms is associated with the presence of risk factors such association with other drugs. This paper aims to present a case report of a patient with generalized gingival overgrowth, with more severe characteristics in the anterior mandible induced by chronic use of nifedipine who underwent basic non-surgical periodontal treatment including supra and subgingival scaling and root planning in both jaws associated with rigorous oral hygiene instructions and surgical therapy in the anterior mandible, the most affected area, to remove the excess of gingival tissue. Nifedipine was replaced by the patient cardiologist to propanolol hydrochloride (40 mg/kg) in an attempt to minimize unwanted side effects. After 6 month follow-up, no recurrence was observed, oral hygiene had improved and the patient had clinical periodontal health and esthetic satisfaction.

Effects of three restorative techniques in the bond strength and nanoleakage at gingival wall of Class II restorations subjected to simulated aging

Objective: To evaluate the effects of simulated aging in bond strength and nanoleakage of class II restorations using three different restorative techniques. Materials and methods: Class II preparations (n = 12) were restored using: FS - composite resin Filtek Supreme Plus (3M/ESPE); RMGIC + FS - resin-modified glass ionomer cement Vitrebond Plus (3M/ESPE) + FS; and FFS + FS - flowable composite resin Filtek Supreme Plus Flowable (3M ESPE) + FS. The teeth were assigned into two groups: Control and Simulated Aging - Thermal/Mechanical cycling (3,000 cycles, 20-80 °C/500,000 cycles, 50 N). From each tooth, two slabs were assessed to microtensile bond strength test (μTBS) (MPa), and two slabs were prepared for nanoleakage assessment, calculated as penetration along the restoration margin considering the penetration length (%) and as the area of silver nitrate particle deposition (μm2). Data were analyzed by two-way analysis of variance (ANOVA) followed by Tukey's post hoc test (p < 0. 05). Results: FS presented the highest μTBS to dentin (22. 39 ± 7. 55 MPa) after simulated aging, while the presence of flowable resin significantly decreased μTBS (14. 53 ± 11. 65 MPa) when compared to no aging condition. Both control and aging groups of RMGIC + FS presented the highest values of silver nitrate penetration (89. 90 ± 16. 31 % and 97. 14 ± 5. 76 %) and deposition area (33. 05 ± 12. 49 and 28. 08 ± 9. 76 μm2). Nanoleakage was not affected by simulated aging. Conclusions: FS presented higher bond strength and lower nanoleakage and was not affected by simulated aging. Use of flowable resin compromised the bond strength after simulated aging. Clinical relevance: The use of an intermediate layer did not improve the dentin bond strength neither reduced nanoleakage at the gingival margins of class II restorations under simulated aging conditions. © 2012 Springer-Verlag.

Effects of surface treatment, hydration and application method on the bond strength of a silorane adhesive and resin system to dentine

Objectives: To evaluate the effects of surface treatment, surface hydration (SH) and application method (AM) on the tensile bond strength of the Silorane Adhesive System (SAS) to dentine. Methods: Ninety bovine teeth were used. For the control group (n = 10), each dentine surface was treated according to the manufacturer's instructions of the SAS. The remaining teeth were randomly distributed into two groups (n = 40), according to the type of dentine surface treatment (ST) - 37% phosphoric acid or Er:YAG Laser prior to the application of the SAS. Each group was further divided into 2 subgroups (n = 20), according to the SH status: dry (D) or wet (W). Each subgroup was further divided into 2 subgroups (n = 10), according to the application method [AM: Active (AC) mode or Passive (PA) mode]. A coat of resin composite (Filtek P90) was applied on the surface. Artificial ageing was performed with a thermo-mechanical cycling machine. The specimens were sectioned into 1 mm × 1 mm × 10 mm sticks and stressed to failure using a universal testing machine. The remaining teeth in each group were used for Scanning Electron Microscopy to examine the fractured area. Data were subjected to a three-way ANOVA, Tukey's test and Dunnet's test (α = 0.05). Results: The ANOVA showed significant differences for SH and AM, but not for ST. For SH, the results of Tukey's test were (in MPa): D-14.9(±3.8)a, W-17.1(±4.3)b; and for AM: PA-14. 9(±4.2)a, AC-17.1(±3.9) b. Conclusions: Acid etching, when combined with a moist dentine surface and the use of primer agitation, improves the bond strength of the SAS to dentine. Clinical Significance: According to the results of the present in vitro study, modification of the application protocols for the silorane-based adhesive system may improve its clinical performance. © 2012 Published by Elsevier Ltd.

Effects of Chronic Stress and Alendronate Therapy on the Osseointegration of Titanium Implants

Purposes: The purposes of this study were to evaluate the influence of chronic stress (CS) on implant osseointegration and also to analyze whether alendronate (ALN) therapy could prevent these eventual stress-negative effects. Materials and Methods: Adult male Holtzmann rats were assigned to one of the four experimental groups: AL (ALN; 1mg/kg/week; n=12), ALS (ALN+CS; 1mg/kg/week; n=12), CTL (sterile physiological saline; n=12), or CTLS (sterile physiological saline+CS; n=12). After 58 days of drug therapy, the ALS and CTLS groups were exposed to CS, and 2 days later all animals underwent tibial implant installation. The animals were euthanized 28 days following the operative surgical procedure. Results: It was observed that the CTLS group presented an impairment of bone metabolism represented by lowest levels of bone-specific alkaline phosphatase and bone area fraction occupancy values. Furthermore, these animals presented a higher proportion of empty osteocytic lacunae. In contrast, the ALN therapy showed increased osseointegration and torque value parameters, regardless of stress exposition. Conclusions: Analysis of the data presented suggests that CS partially impairs the osseointegration of tibial implants and that ALN therapy is able to prevent these negative effects. © 2013 Wiley Periodicals, Inc.

Effects of extreme cooling methods on mechanical properties and shear bond strength of bilayered porcelain/3Y-TZP specimens

Objectives: This study investigated the effect of extreme cooling methods on the flexural strength, reliability and shear bond strength of veneer porcelain for zirconia. Methods: Vita VM9 porcelain was sintered on zirconia bar specimens and cooled by one of the following methods: inside a switched-off furnace (slow), at room temperature (normal) or immediately by compressed air (fast). Three-point flexural strength tests (FS) were performed on specimens with porcelain under tension (PT, n = 30) and zirconia under tension (ZT, n = 30). Shear bond strength tests (SBS, n = 15) were performed on cylindrical blocks of porcelain, which were applied on zirconia plates. Data were submitted to one-way ANOVA and Tukey's post hoc tests (p < 0.05). Weibull analysis was performed on the PT and ZT configurations. Results: One-way ANOVA for the PT configuration was significant, and Tukey's test revealed that fast cooling leads to significantly higher values (p < 0.01) than the other cooling methods. One-way ANOVA for the ZT configuration was not significant (p = 0.06). Weibull analysis showed that normal cooling had slightly higher reliability for both the PT and ZT configurations. Statistical tests showed that slow cooling decreased the SBS value (p < 0.01) and showed less adhesive fracture modes than the other cooling methods. Clinical Significance: Slow cooling seems to affect the veneer resistance and adhesion to the zirconia core; however, the reliability of fast cooling was slightly lower than that of the other methods. © 2013 Elsevier Ltd.

The acute effects of static stretching on peak force, peak rate of force development and muscle activity during single- and multiple-joint actions in older women

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effects of resistance training on the performance of activities of daily living in patients with Alzheimer's disease

Aim: The objective of this study was to investigate the effects of resistance training in activities of daily living performance in Alzheimer's disease (AD) patients. Methods: An exploratory and longitudinal study, lasting for 16weeks, with the participation of 34 patients divided equally in: the training group (TG), who participated in a resistance training protocol (three sets of 20 repetitions in five exercises); and the social gathering group (SGG), who participated in a social interaction protocol (i.e. group dynamics, writing and reading activities). Results: We observed significant differences between the groups in moving around the house, climbing stairs, standing up from the floor and putting on socks tests. Conclusion: This study showed that resistance training improves agility, lower limb strength, balance and flexibility in AD patients, while SGG protocol is important to improve the agility. © 2012 Japan Geriatrics Society.

The effects of combined aerobic and resistance training on heart rate variability in postmenopausal women

Model of the study: Controlled clinical trial. Objective: To verify the effects of 16 weeks of combined aerobic and resistance training on cardiac autonomic modulation in menopausal women. Methods: 17 menopausal women were divided into two groups: the training group (TG: n=11) and control group (CG: n=6). The body composition variables were estimated using dual-energy X-ray absorptiometry. The cardiac autonomic modulation was evaluated by heart rate variability using linear indexes. The training protocol consisted of 16 weeks of 50 minutes of resistance training and 30 minutes of aerobic training. Results: For the TG there was an increase in the rMSSD(ms) index (pre:17,4±3,7 and post:24,8±13,1, p<0,045), an increase in the duration of the intervals between the cardiac beats(ms) (pre:891,2±80,2 and post:974,1±71,4, p<0,003) and in the values of heart rate(bpm) (pre:68,1±6,4 and post:62,0±4,7, p<0,003), additionally for the spectral indexes in normalized units, changes for LF (pre:52,2±13,1 and post:44,5±12,4, p<0,025) and HF (pre:47,8±13,3 and post:55,5±12,4, p<0,025) were noticed, demonstrating increased parasympathetic and reduced sympathetic. There were no significant differences to CG. Conclusion: combined aerobic and resistance training promoted benefits to the autonomic modulation in menopausal women.

Effects of zoledronic acid on odontoblast-like cells

The aim of the study was to evaluate the effects of a highly potent bisphosphonate, zoledronic acid (ZOL), on cultured odontoblast-like cells MDPC-23. The cells (1.5 × 104 cells/cm2) were seeded for 48 h in wells of 24-well dished. Then, the plain culture medium (DMEM) was replaced by fresh medium without fetal bovine serum. After 24 h, ZOL (1 or 5 μM) was added to the medium and maintained in contact with the cells for 24 h. After this period, the succinic dehydrogenase (SDH) enzyme production (cell viability-MTT assay), total protein (TP) production, alkaline phosphatase (ALP) activity, and gene expression (qPCR) of collagen type I (Col-I) and ALP were evaluated. Cell morphology was assessed by SEM. Five μM ZOL caused a significant decrease in SDH production. Both ZOL concentrations caused a dose-dependent significant decrease in TP production and ALP activity. ZOL also produced discret morphological alterations in the MDPC-23 cells. Regarding gene expression, 1 μM ZOL caused a significant increase in Col-I expression. Although 5 μM ZOL did not affect Col-I expression, it caused a significant alteration in ALP expression (ANOVA and Tukey's test, p < 0.05). ZOL presented a dose-dependent cytotoxic effect on the odontoblast-like cells, suggesting that under clinical conditions the release of this drug from dentin could cause damage to the pulpo-dentin complex. © 2012 Elsevier Ltd.

Biostimulatory effects of low-level laser therapy on epithelial cells and gingival fibroblasts treated with zoledronic acid

Low-level laser therapy (LLLT) has been considered as an adjuvant treatment for bisphosphonate-related osteonecrosis, presenting positive clinical outcomes. However, there are no data regarding the effect of LLLT on oral tissue cells exposed to bisphosphonates. This study aimed to evaluate the effects of LLLT on epithelial cells and gingival fibroblasts exposed to a nitrogen-containing bisphosphonate - zoledronic acid (ZA). Cells were seeded in wells of 24-well plates, incubated for 48 h and then exposed to ZA at 5 μM for an additional 48 h. LLLT was performed with a diode laser prototype - LaserTABLE (InGaAsP - 780 nm ± 3 nm, 25 mW), at selected energy doses of 0.5, 1.5, 3, 5, and 7 J cm-2 in three irradiation sessions, every 24 h. Cell metabolism, total protein production, gene expression of vascular endothelial growth factor (VEGF) and collagen type I (Col-I), and cell morphology were evaluated 24 h after the last irradiation. Data were statistically analyzed by Kruskal-Wallis and Mann-Whitney tests at 5% significance. Selected LLLT parameters increased the functions of epithelial cells and gingival fibroblasts treated with ZA. Gene expression of VEGF and Col-I was also increased. Specific parameters of LLLT biostimulated fibroblasts and epithelial cells treated with ZA. Analysis of these in vitro data may explain the positive in vivo effects of LLLT applied to osteonecrosis lesions. © 2013 Astro Ltd.