Relação entre materiais dentários e o complexo dentino-pulpar

Despite the strong valorization of the esthetics and its relationship with restorative materials, the biological principles of any clinical procedure are extremely important to maintain the vitality of the dentin-pulp complex. Dentin and pulp tissue are susceptible to different kinds of irritants such as toxins from microorganisms, traumatic procedures of cavity preparation, as well as toxic components released by restorative materials applied in non recommended clinical situations. Initially, the pulp responds to irritation by starting an inflammatory reaction which involves outward movement of dentinal fluid and intratubular deposition of immunoglobulins, upregulation of odontoblast activities, presence of immune cells and their cytokines as well as local expression of neuropeptides and chemokines. After these initial events, the inflammation process can be resolved associated or not to sclerotic dentin formation and reactionary dentin deposition. If high intensity offensive stimuli are applied to the dentin-pulp complex, death of odontoblasts takes place and consequently pulp ageing or even partial necrosis of this tissue may occurs. Thereby, clinicians need to be aware about the physiological and pathological features of the dentin-pulp complex as well as the possible biological consequences of different clinical procedures. In this way, the dentists should be able to carry out minimally aggressive operative techniques and to select the more appropriate restorative materials for each specific clinical situation in order to obtain excellent clinical results associated to the maintenance of pulp vitality.

Longitudinal results of a 10-year clinical trial of repair of amalgam restorations

The aim of this prospective, blind, and randomized clinical trial was to assess the effectiveness of repair of localized clinical defects in amalgam restorations that were initially scheduled for replacement. A cohort of 20 patients with 40 (Class I and Class II) amalgam restorations that presented one or more clinical features that deviated from the ideal (Bravo or Charlie) according to US Public Health Service criteria, were randomly assigned to either the repair or the replacement group—A: repair, n = 19; and B: replacement, n = 21. Two examiners who had calibration expertise evaluated the restorations at baseline and 10 years after according to seven parameters: marginal occlusal adaptation, anatomic form, surface roughness, marginal staining, contact, secondary caries, and luster. After 10 years, 30 restorations (75%) were evaluated (Group A: n = 17; Group B: n = 13). Repaired and replaced amalgam restorations showed similar survival outcomes regarding marginal defects and secondary caries in patients with low and medium caries risk, and most of the restorations were considered clinically acceptable after 10 years. Repair treatment increased the potential for tooth longevity, using a minimally interventional procedure. All restorations trend to downgrade over time.

Métodos alternativos no ensino da técnica cirúrgica veterinária

Pós-graduação em Cirurgia Veterinária - FCAV

Single-port retroperitoneal renal biopsy using standard urological instruments

Objective: To describe the surgical technique and initial experience with a single-port retroperitoneal renal biopsy (SPRRB).Materials and Methods: Between January and April 2013, five children underwent SPRRB in our hospital. A single 1.5 cm incision was performed under the 12th rib at mid-axillary line, and an 11 mm trocar was inserted. A nephroscope was used to identify the kidney and dissect the perirenal fat. After lower pole exposure, a laparoscopic biopsy forceps was introduced through the nephroscope working channel to collect a renal tissue sample.Results: SPRRB was successfully performed in five children. The mean operative time was 32 minutes, and mean estimated blood loss was less than 10 mL. The hospital stay of all patients was two days because they were discharged in the second postoperative day, after remaining at strict bed rest for 24 hours after the procedure. The average number of glomeruli present in the specimen was 31.Conclusion: SPRRB is a simple, safe and reliable alternative to open and videolaparoscopic approaches to surgical renal biopsy.

Effect of ceramic etching protocols on resin bond strength to a feldspar ceramic

This study sought to evaluate the resin micro-tensile bond strength (MTBS) stability of a leucite-reinforced ceramic after different ceramic etching protocols. The microtensile test had 40 ceramic blocks (5x5x6 mm) assigned to five groups (n=8), in accordance with the following surface etching protocols: NE nonetched (control); 9HF: hydrofluoric (HF) acid etching (9% HF)+wash/dry; 4HF: 4%HF+wash/dry; 5HF: 5%HF+wash/dry; and 5HF+N: 5%HF+neutralizer+wash/dry+ultrasonic-cleaning. Etched ceramic surfaces were treated with a silane agent. Next, resin cement blocks were built on the prepared ceramic surface and stored for 24 hours in distilled water at 37 degrees C. The specimens were then sectioned to obtain microtensile beams (32/block), which were randomly assigned to the following conditions, nonaged (immediate test) and aged (water storage for 150 days plus 12,000 thermal cycles), before the microtensile test. Bond strength data were submitted to one-way analysis of variance and Tukey test (alpha=0.05). Additional ceramic samples were subjected to the different ceramic etching protocols and evaluated using a scanning electron microscope (n=2) and atomic force microscopy (n=2). Aging led to a statistically significant decrease in the MTBS for all groups, except the untreated one (NE). Among the groups submitted to the same aging conditions, the untreated (NE) revealed inferior MTBS values compared to the 9HF and 4HF groups. The 5HF and 5HF+N groups had intermediate mean values, being statistically similar to the higher values presented by the 9HF and 4HF groups and to the lower value associated with the NE group. The neutralization procedure did not enhance the ceramic/resin cement bond strength. HF acid etching is a crucial step in resin/ceramic bonding.

Ovum pick-up technique in recently weaned ewe lambs subjected to ovarian stimulation

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

Effect of recasting procedure upon corrosion behavior and metallic ion release of Co-Cr-Mo dental alloy in physiological

Recasting process influence upon corrosion behavior of Co-Cr-Mo dental alloy in simulated physiological serum has been investigated using chemical and electrochemical techniques. Recast Co-Cr-Mo alloy by induction (IND) or by blowtorch (FLAME) has exhibited similar dendritic structures. Both IND and FLAME alloys have presented good corrosion resistance in physiological serum. Passivation process provides this corrosion resistance. Codissolution makes this process difficult. Passive films, formed on these alloys, have been analyzed as a dual layer consisting of an inner barrier and an outer porous layer. Passive film protective characteristics are higher in FLAME than in IND alloy. On this last alloy, the passive film is more porous due to a higher Codissolution. ©Carl Hanser Verlag, München.

Running-based anaerobic sprint test as a procedure to evaluate anaerobic power

The aim of this study was to evaluate the use of the running anaerobic sprint test (RAST) as a predictor of anaerobic capacity, compare it to the maximal accumulated oxygen deficit (MAOD) and to compare the RAST's parameters with the parameters of 30-s all-out tethered running on a treadmill. 39 (17.0±1.4 years) soccer players participated in this study. The participants underwent an incremental test, 10 submaximal efforts [50-95% of velocity correspondent to VO2MAX (vVO2MAX)] and one supramaximal effort at 110% of vVO2MAX for the determination of MAOD. Furthermore, the athletes performed the RAST. In the second stage the 30-s all-out tethered running was performed on a treadmill (30-s all-out), and compared with RAST. No significant correlation was observed between MAOD and RAST parameters. However, significant correlations were found between the power of the fifth effort (P5) of RAST with peak and mean power of 30-s all-out (r=0.73 and 0.50; p<0.05, respectively). In conclusion, the parameters from RAST do not have an association with MAOD, suggesting that this method should not be used to evaluate anaerobic capacity. Although the correlations between RAST parameters with 30-s all-out do reinforce the RAST as an evaluation method of anaerobic metabolism, such as anaerobic power.

Influência da aplicação de laser de baixa intensidade no recobrimento radicular associado à técnica de enxerto de tecido conjuntivo em indivíduos fumantes: ensaio clínico controlado randomizado

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

Analgesia controlada pelo paciente comparada a analgesia padrão na função pulmonar, força muscular respiratória e dor no pós-operatório e revascularização do miocárdio: ensaio clínico randonizado

Pós-graduação em Bases Gerais da Cirurgia - FMB

EMERGENT CONDITIONAL RELATIONS IN A GO/NO-GO PROCEDURE: FIGURE-GROUND AND STIMULUS-POSITION COMPOUND RELATIONS

Past research has demonstrated emergent conditional relations using a go/no-go procedure with pairs of figures displayed side-by-side on a computer screen. The present Study sought to extend applications Of this procedure. In Experiment, 1, we evaluated whether emergent conditional relations Could be demonstrated when two-component stimuli were displayed in figure-ground relationships-abstract figures displayed on backgrounds of different colors. Five normal)), capable adults participated. During training, each two-component stimulus Was presented successively. Responses emitted in the presence of some Stimulus pairs (A1B1, A2B2, A3B3, B1C1, B2C2 and B3C3) were reinforced, whereas responses emitted in the presence of other pairs (A1B2, A1B3, A2B1, A2B3, A3B1, A3B2, B1C2, B1C3, B2C1, B2C3, B3C1 and B3C2) were not. During tests, new configurations (AC and CA) were presented, thus emulating structurally the matching-to-sample tests employed in typical equivalence Studies. All participants showed emergent relations consistent with stimulus equivalence during testing. In Experiment 2, we systematically replicated the procedures with Stimulus compounds consisting Of four figures (A1, A2, C1 and C2) and two locations (left - B1 and right - 132). A,11 6 normally capable adults exhibited emergent stimulus-stimulus relations. Together, these experiments show that the go/no-go procedure is a potentially useful alternative for Studying emergent. conditional relations when matching-to-sample is procedurally cumbersome or impossible to use.

Influence of the use of Aliquat 336 in the immobilization procedure in sol-gel of lipase from Bacillus sp ITP-001

Aliquat 336, a liquid hydrophobic material, was used at different concentrations (0.5-3.0%, w/v) as an additive in the preparation of encapsulated lipase from Bacillus sp. ITP-001 on sol-gel silica matrices using tetraethoxysilane (TEOS) as the precursor. The resulting hydrophobic matrices and immobilized lipases were characterized with regard to specific surface area (BET method), adsorption-desorption isotherms, pore volume (Vp) and size (dp) by nitrogen adsorption (BJH method) and scanning electron microscopy (SEM). The catalytic activities and the corresponding coupling yields were assayed in the hydrolysis of olive oil. In comparison with pure silica matrices, the immobilization process in the presence of Aliquat 336 decreased the values for specific surface area and increased the values for pore specific volume (Vp) and mean pore diameter (dp). This behavior may be related to the partial adsorption of the enzyme on the external surface of the hydrophobic matrix as indicated by scanning electron microscopy. Aliquat 336 concentrations in the range from 0.5 to 1.5% (w/v) provided immobilized derivatives with higher coupling yields and better substrate affinity. The highest coupling yield (Y-A = 71%) was obtained for the immobilized enzyme prepared in the presence of 1.5% Aliquat which gave the following morphological properties: specific surface area = 183 m(2)/g, pore specific volume (Vp) = 0.36 cc/g and mean pore diameter (dp)= 91 angstrom. (c) 2012 Elsevier B.V. All rights reserved.

Cleft lip and palate: recommendations for dental anesthetic procedure based on anatomic evidences

Patients with cleft lip and palate usually present dental anomalies of number, shape, structure and position in the cleft area and the general dentist is frequently asked to restore or extract those teeth. Considering that several anatomic variations are expected in teeth adjacent to cleft areas and that knowledge of these variations by general dentists is required for optimal treatment, the objectives of this paper are: 1) to describe changes in the innervation pattern of anterior teeth and soft tissue caused by the presence of a cleft, 2) to describe a local anesthetic procedure in unilateral and bilateral clefts, and 3) to provide recommendations to improve anesthetic procedures in patients with cleft lip and palate. The cases of 2 patients are presented: one with complete unilateral cleft lip and palate, and the other with complete bilateral cleft lip and palate. The patients underwent local anesthesia in the cleft area in order to extract teeth with poor bone support. The modified anesthetic procedure, respecting the altered course of nerves in the cleft maxilla and soft tissue alterations at the cleft site, was accomplished successfully and the tooth extraction was performed with no pain to the patients. General dentists should be aware of the anatomic variations in nerve courses in the cleft area to offer high quality treatment to patients with cleft lip and palate.

Clinical and nutritional status in the late postoperative of pancreaticoduodenectomy. Influence of pylorus preservation procedure

PURPOSE: To evaluate the nutritional status of patients in the late postoperative period of pancreaticoduodenectomy (PD) and compare the long-term outcome according to pylorus-preserving (PPPD) or the standard technique (SPD) in which the pylorus is resected. METHODS: This prospective study was conducted twelve months prior or more in patients who had underwent PD (PD Group, n=15) and health volunteers (Control Group, n=15). At a post hoc analysis, the PD Group was divided in PPPD Subgroup (n=9) and SPD Subgroup (n=6), according to the PD techniques. Gastrointestinal complaints and nutritional status were evaluated, apart from a biochemical assessment; Student t-test or Mann-Whitney test were used. RESULTS: The patients recovered their body weight and the gastrointestinal complaints were uncommon. The PD Group showed higher energy and protein intake even though BMI was lower than in Control Group. There were no differences in laboratorial data, except for higher glycemia, serum alkaline phosfatase and C-reactive protein in PD Group. There was no difference in the various parameters evaluated when the Subgroups (PPPD and SPD) were compared. CONCLUSION: For long-term pancreaticoduodenectomy, the gastrointestinal symptoms are minimal and the patients had the clinical and nutritional status preserved, regardless of pylorus preservation.

Effect of different restorative procedures on the fracture resistance of teeth submitted to internal bleaching

The aim of this study was to evaluate the influence of different restorative procedures on the fracture resistance of endodontically treated teeth submitted to intracoronal bleaching. Fifty upper central incisors were distributed into 5 groups: GI - healthy teeth; GII - endodontically treated teeth sealed with Coltosol; GIII - endodontically treated teeth bleached and sealed with Coltosol; GIV - endodontically treated teeth bleached and restored with composite resin; and GV - endodontically treated teeth bleached and restored with a fiberglass post and composite resin. In the bleached specimens, a cervical seal was made prior to bleaching with 38% hydrogen peroxide. The gel was applied on the buccal surface and in the pulp chamber, and was then light-activated for 45 s. This procedure was repeated three times per session for four sessions, and each group was submitted to the restorative procedures described above. The specimens were submitted to fracture resistance testing in a universal testing machine. There were statistically significant differences among the groups (p < 0.05). The mean value found for GIII was the lowest (0.32 kN) and was significantly different from the values found for GI (0.75 kN), GII (0.67 kN), GIV (0.70 kN), and GV (0.72 kN), which were not significantly different from each other (p > 0.05). The restorative procedures using composite resin were found to successfully restore the fracture resistance of endodontically treated and bleached teeth.