Occluding Efficiency of Different Desensitizing Agents and Er,Cr:YSGG Laser on Dentin Tubules.

PURPOSE: This study aimed to evaluate the effects of two desensitizers and the Er,Cr:YSGG laser on human dentin tubules, applied alone or in combination. METHODS: Ninety-six dentin specimens were obtained from extracted third molars and divided into six groups: Group 1: no-treatment (Control); Group 2: nano-hydroxyapatite desensitizer (NhapD); Group 3: NhapD+Er,Cr:YSGG laser (L); Group 4: Er,Cr:YSGG laser (L); Group 5: glutaraldehyde desensitizer (GD); and Group 6: GD+L, respectively. All specimens were evaluated using scanning electron microscopy. The diameter and the number of open dentin tubules, the tubules' occluding ratio, and the mineral coverage area were measured via the Image J software at 2000× magnification. Atomic force microscopy was used to determine the blocking mechanism of desensitizing treatments and the surface morphology of dentin specimens. One-way ANOVA and Tukey tests were used for statistical analysis. RESULTS: The number of open tubules and the mean diameter of tubules for all treatment groups showed statistically significant differences from the control group The NhapD+L group had a significantly lower number of open tubules than the L and GD groups. The NhapD+L and L groups significantly had higher occluding ratios than the other groups. CONCLUSIONS: The present study showed that the Er,Cr:YSGG laser alone was effective in terms of tubule occlusion and also contributed to increasing the occluding ratio of nano-hydroxyapatite. It may be recommended to use the Er,Cr:YSGG laser with nano-hydroxyapatite desensitizers to achieve effective tubule occlusion.

Twelve-month Clinical Performance Evaluation of a Glass Carbomer Restorative System.

OBJECTIVE: The aim of this in vivo study was to evaluate the clinical one-year follow-up of a silica- and flouroapatite-reinforced glass carbomer filling material as compared to a resin composite restorative material. METHODS AND MATERIALS: In this study, a total of 100 restorations were performed. Caries were removed conventionally with diamond burs. Half of the restorations were restored with nanocomposite resin (TEP) (Tokuyama Estelite, Tokuyama Dental, Japan) and the other half were restored with glass carbomer (GC) material (GCP Dental, The Netherlands). Each restorative material was applied according to the manufacturer's instructions. Restorations were evaluated with modified USPHS criteria at the end of the first week, 6 months, and 12 months. Data were analyzed using Fisher's Exact Chi-Square test, Fisher Freeman Halton Test, and Continuity (Yates) Correction. The Wilcoxon sign test was used for intra-group comparisons of the parameters. RESULTS: When the filling materials were compared with one another, a statistically significant difference was observed in the 12th month on the marginal discoloration. A statistically significant difference was observed between the two materials in the 6th month on the marginal adaptation (p<0.05). CONCLUSIONS: In view of these results, there is a need to improve the physical properties of the GC filling material in further in vivo studies.

Protective effect of quercetin on some hematological parameters in rats exposed to cadmium.

We investigated the effects of quercetin (Q) on some hematological parameters and determined the percentage of alpha-naphthyl acetate esterase (ANAE) positive lymphocytes in rats that had been exposed to cadmium (Cd). Thirty male Wistar albino rats were divided into four groups: control (C), quercetin (Q), cadmium (Cd) and Q + Cd (CdQ). Blood samples were taken to assess erythrocytes (RBC), leukocytes (WBC), hemoglobin levels (Hb), hematocrit values (Hct), platelets (PLT), alpha-naphthyl acetate esterase (ANAE) positive lymphocytes. RBC, Hb, Hct; the number of PLT significantly decreased in the Cd group. To the contrary, these parameters were increased significantly in the CdQ group compared to the Cd group. Although we found a significant increase in total WBC count and neutrophil percentage, the number of lymphocytes decreased in the Cd group compared to the other three groups. Also, the percentage of peripheral blood ANAE positive lymphocytes decreased significantly in the Cd group (p < 0.05). Q exhibits positive effects on some hematological characteristics and the percentage of ANAE positive lymphocyte in cases of acute CD toxicity.

The effect of calcium phosphate-containing desensitizing agent on the microtensile bond strength of multimode adhesive agent.

OBJECTIVE: The aim of this study was to investigate the effect of calcium phosphate containing desensitizing pretreatments on the microtensile bond strength (MTBS) and microleakage of the multimode adhesive agent to dentin. MATERIALS AND METHODS: In this study, twelve noncarious, freshly extracted human third molar teeth for MTBS and 20 premolar teeth for the microleakage test were used. The teeth were restored using Clearfil Universal Bond + Clearfil APX and Teeth mate Desensitizer (TMD). For MTBS test, Group 1: Self-etch, Group 2: Etch and rinse (G1 and 2, nondesensitizer treatment served as a control), Group 3: TMD/self-etch, Group 4: Acid-etch/TMD/etch and rinse. For microleakage test, Class V adhesive cavities (3 mm × 2 mm × 2 mm) were prepared and restored as mentioned before. The restored teeth were subjected to thermal cycling. The MTBS test was performed in all procedures. The MTBS data were submitted to a one-way ANOVA and post hoc Tukey test (P P Results: Control groups exhibited a higher mean MTBS value than TMD groups, and there were statistical differences between the groups. TMD groups also demonstrated significantly less microleakage than control groups (P Conclusions: This study proves that the application of TMD with a multimode adhesive bonding system produced significantly lower MTBS and microleakage.

The impact of Er:YAG laser enamel conditioning on the microleakage of a new hydrophilic sealant--UltraSeal XT hydro.

UltraSeal XT hydro is a new hydrophilic, light-cured, methacrylate-based pit and fissure sealant which has been developed by Ultradent Products, USA. The sealant is highly filled with a 53 wt.% mixture of inorganic particles which confer both thixotropy and radiopacity. The principal purpose of this study was to investigate the microleakage of UltraSeal XT hydro as a function of different enamel etching techniques. The occlusal surfaces of sound, extracted human molars were either acid etched, Er:YAG laser irradiated or successively laser irradiated and acid etched. UltraSeal XT hydro was applied to each group of teeth (n = 10) which were subjected to a thermocycling process consisting of 2500 cycles between 5 and 50 °C with a dwell time of 30 s. Microleakage assessments were then carried out using 0.5% fuchsin dye and optical microscopy. The microleakage score data were analysed using the Kruskal-Wallis, Mann-Whitney U test with Bonferroni adjustment. No significant differences in microleakage were noted between the individually acid etched and laser-irradiated groups (p > 0.05); however, teeth treated with a combination of laser irradiation and acid etching demonstrated significantly lower microleakage scores (p < 0.001). Electron microscopy with energy-dispersive X-ray analysis revealed that the mineral filler component of UltraSeal XT hydro essentially comprises micrometre-sized particles of inorganic silicon-, aluminium- and barium-bearing phases. Laser etching increases the roughness of the enamel surface which causes a concentrated zoning of the filler particles at the enamel-sealant interface.

Effects of traditional homemade koumiss on some hematological and biochemical characteristics in sedentary men exposed to exercise.

We evaluated the effects of koumiss on some hematological and biochemical characteristics of persons who exercise. Eighteen sedentary males were assigned to three equal groups: koumiss (K), koumiss + exercise (KE) and exercise alone (E). Leukocytes (WBC), differential leucocyte count, erythrocytes (RBC), hemoglobin (HGB), hematocrit (HCT), platelet (PLT), glucose, total cholesterol, triglycerides, high density lipoprotein (HDL), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were assessed In blood samples. By the end of the study, triglycerides (TG) and cholesterol levels tended to decrease in all groups, but the decrease was significant only at day 15 for the KE group. HDL tended to be increased in all groups at day 15, but the increase was significant only in the KE group. We found that koumiss had beneficial effects on some hematological and biochemical characteristics.

The protective effect of L-carnitine against hippocampal damage due to experimental formaldehyde intoxication in rats.

We investigated the protective effects of L-carnitine on hippocampus tissue damage in rats during experimental formaldehyde (FA) intoxication. Male Wistar albino rats were assigned into four groups: (1) control (C), (2) formaldehyde (FA), (3) formaldehyde + 0.5 g/kg of L-carnitine (FA + 0.5 LC) (4) formaldehyde + 1 g/kg L-carnitine (FA + 1 LC). At the end of the 14 day trial period, animals were sacrificed by decapitation under anesthesia. The hippocampus tissue samples were extracted to measure MDA, GSH and SOD activity. Neuronal degeneration was assessed based on histopathological (hematoxylin and eosin) and immunohistochemical (anti-ubiquitin) examination. To detect oxidative stress, specimens were reacted with anti-Cu/Zn-SOD antibody. After administering L-carnitine with FA to the animals, the activities of SOD and GSH increased, but the levels of MDA decreased in hippocampus tissue. Neuronal degeneration was observed in the FA group. L-carnitine administration reduced neuronal degeneration and histological structure was similar to controls. After FA application, degenerated hippocampus neurons were stained with anti-ubiquitin and Cu/Zn-SOD antibodies; weakly positive staining was observed in L- carnitine-treated groups. L-carnitine may be useful for preventing oxidative damage in the hippocampus tissue due to formaldehyde intoxication.

Efeitos da inclinação de agulha peridural e diferentes velocidades de injeção na distribuição de anestesia peridural / Effects of epidural needle rotation and different speeds of injection on the distribution of epidural block / Efectos de la inclinación de la aguja epidural y diferentes velocidades en la distribución de la anestesia epidural

JUSTIFICATIVA E OBJETIVOS: Este estudo prospectivo e randomizado avaliou o efeito das velocidades da injeção na anestesia peridural unilateral sobre as características do bloqueio, parâmetros hemodinâmicos e critérios de alta hospitalar em 60 pacientes. Levobupivacaína a 5% foi administrada nos pacientes (n = 30) do Grupo F durante 1 minuto (rápido) e durante 3 minutos nos pacientes (n = 30) do Grupo S (lento), com agulha em ângulo de 5º-10º a partir da linha média. O sucesso da anestesia peridural unilateral foi mais significante no Grupo S do que no Grupo F (70,3% vs 16%, p < 0,001). Nos pacientes do Grupo S, o tempo necessário para o nível máximo de bloqueio sensitivo nos lados não operados foi mais curto e o tempo de regressão para dois segmentos, mais longo (p < 0,05). O tempo para walk-out foi mais longo no Grupo F (p < 0,05). Consideramos que a administração lenta de anestésico local em anestesia peridural unilateral é mais eficaz do que a administração rápida.

BACKGROUND AND OBJECTIVES: This prospective, randomised study examined the effect of injection speeds for unilateral epidural anesthesia on block characteristics, hemodynamic parameters, and discharge criteria in 60 patients. Levobupivacaine 5% was administered to Group F over 1 min (fast) and to Group S over 3 min (slow) (n = 30 each) with the needle angulated at 5º-10º from the midline. Unilateral epidural block was significantly more successful in Group S than in Group F (70.3% vs. 16%; p < 0.001). On the non-operated sides in group S, the maximal sensorial block time was shorter and the regression time for 2 segments was longer (p < 0.05). And the walk-out time was longer in group F (p < 0.05). We consider that the slow administration of local anesthetic in unilateral epidural anesthesia is more effective than rapid administration.

JUSTIFICATIVA Y OBJETIVOS: Este estudio prospectivo y aleatorio ha evaluado el efecto de las velocidades de la inyección para la anestesia epidural unilateral sobre las características del bloqueo, parámetros hemodinámicos y criterios del alta hospitalaria en 60 pacientes. La levobupivacaína al 5% se administró en los pacientes (n = 30) del Grupo F durante 1 minuto (rápido) y durante 3 minutos en los pacientes (n = 30) del grupo S (lento), con una aguja en ángulo de 5º-10º a partir de la línea media. El éxito de la anestesia epidural unilateral fue más significativo en el Grupo S que en el Grupo F (70,3% vs 16%, p < 0,001). En los pacientes del Grupo S, el tiempo necesario para el nivel máximo de bloqueo sensitivo en los lados no operados fue más corto y el tiempo de regresión para los dos segmentos, más largo (p < 0,05). El tiempo para walk-out fue más largo en el Grupo F (p < 0,05). Consideramos que la administración lenta de anestésico local en la anestesia epidural unilateral es más eficaz que la administración rápida.

Effects of epidural needle rotation and different speeds of injection on the distribution of epidural block.

BACKGROUND AND OBJECTIVES: This prospective, randomised study examined the effect of injection speeds for unilateral epidural anesthesia on block characteristics, hemodynamic parameters, and discharge criteria in 60 patients. Levobupivacaine 5% was administered to Group F over 1 min (fast) and to Group S over 3 min (slow) (n=30 each) with the needle angulated at 5°-10° from the midline. Unilateral epidural block was significantly more successful in Group S than in Group F (70.3% vs. 16%; p<0.001). On the non-operated sides in group S, the maximal sensorial block time was shorter and the regression time for 2 segments was longer (p<0.05). And the walk-out time was longer in group F (p<0.05). We consider that the slow administration of local anesthetic in unilateral epidural anesthesia is more effective than rapid administration.

Ultrastructural correlates of in vivo/in vitro bond degradation in self-etch adhesives.

The morphologic correlates of bond degradation in self-etching primers have not been fully elucidated. We hypothesized that there is no difference between the mechanism of degradation of self-etching primers in vivo and in vitro. Class I cavities prepared in vivo in 24 caries-free human molars were bonded with Clearfil SE Bond or Clearfil Protect Bond, and restored with resin composites. Eight teeth were extracted after 24 hrs, and the rest after 1 yr. The same protocol was repeated in vitro with extracted molars. Degradation of resin-dentin bonds was assessed by microtensile bond testing and TEM of interfaces after tracer immersion. Both in vivo and in vitro bond strengths decreased with time for SE Bond but not for Protect Bond, with more pronounced water treeing observed in the former adhesive under both aging conditions. There is no difference between the mechanism of degradation of self-etch adhesives in vivo or in vitro.

Effects of increasing zinc supplementation in drinking water on growth and thyroid gland function and histology in broiler chicks.

The aim of the study was to examine the effects of increasing zinc supplementation on growth, feed efficiency and thyroid function and histology in broiler chicks. Sixty new born male broiler chicks were randomly allotted into one of four treatment groups and fed for 60 d. Zinc (Zn) was added into drinking water at the levels of 0, 125, 500, and 1000 mg Zn/L. Body weight gain were significantly higher and feed efficiency were significantly lower in chicks supplemented with 125 mg Zn/L compared with chicks supplemented with 500 or 1000 mg Zn/L at the end of the experiment. Serum Zn concentration linearly increased with the increasing level of Zn intake. Serum triiodothyronine and thyroxine levels and the diameters of follicles of thyroid gland were significantly reduced with high levels (500 and 1000 mg Zn/L) of Zn intake at the end of the experiment. It was concluded that chick receiving 1000 mg Zn/L as ZnSO4.7H2O in drinking water showed signs of Zn toxicity.