No abstract

A series of novel prodrugs of naproxen has been synthesized. Naproxen (1) was reacted with thionyl chloride to yield acid chloride (2) which was further reacted with glucose to form the glucosyl naproxen (3). Tetra-acetate of glucosyl naproxen was prepared and finally reacted with different amino acids to yield the title compounds. These compounds were evaluated for analgesic, anti-inflammatory activities, and for possible GI toxicity. Compound 5b depicted most potent analgesic activity with percentage inhibition of 98.15%. Compound 5a was found to be most potent anti-inflammatory agent with 76% inhibition. Compound 5n was second most active analgesic (92.26%) and anti-inflammatory (73%) agent. In vitro hydrolysis pattern of synthesized prodrugs was studied in phosphate buffer of pH 7.4 and acetate buffers of pH 3.0, 4.0, and 5.0, respectively. Selected compounds were evaluated for their ulcerogenic potential and all the tested derivatives were significantly less irritating to gastric mucosa than the parent drug.

Contemporary calcium silicate materials can be used as dentin substitute materials in "open sandwich" Class II restorations. This study evaluates the marginal adaptation of Biodentine, MTA Plus, and resin modified glass ionomer cement used as dentin substitutes and reports better adaptation obtained with Biodentine and glass ionomer cement.

Objectives:This study evaluated the effect of ionizing radiations on resin–dentin interface in terms of marginal adaptation and micro-tensile bond strength under thermocycling and mechanical loading.Materials and Methods:Forty extracted human mandibular third molars were divided into four groups. GR I: No Irradiation and Class II MO cavities were prepared that were restored with composite restorations; GR II: Teeth were irradiated and restored; GR III: Teeth were restored and irradiated; GR IV: Teeth were restored during irradiation dosage fractions. All samples were thermal and mechanical loaded with 5000 cycles, 5 ± 2-55 ± 2°C, dwell time 30 s and 150,000 cycles at 60N. Resin–dentin slabs were trimmed into dumbbell-shaped slabs and microtensile bond strength was measured. The bond strength data was analyzed by one-way analysis of variance test.Results and Conclusions:Irradiation before tooth preparation deteriorated the microtensile bond strength.

Background: The aim of this study was to evaluate the influence of chemomechanical caries removal and conventional caries excavation on the microtensile bond strength of three different dentine adhesive systems. Methods: Thirty extracted human mandibular molars with radiographic signs of dental caries extending up to the middle third of dentine were sectioned longitudinally through the centre of the carious lesion in a buccolingual direction to yield two sections. One half of each tooth was excavated by tungsten carbide bur and the other half was chemomechanically treated with Carisolv ® . Three dentine bonding systems: an etch-and-rinse single bottle adhesive (Single Bond, 3M ESPE); a two bottle, two-step self-etch bonding system (One Coat Self Etching Bond, Coltene Whaledent); and a single-step, single bottle self-etch adhesive (Adper Easy Bond Self-Etch Adhesive, 3M ESPE) were applied and composite build-up was done. The specimens were tested for microtensile bond strength. Data were analysed using two-way analysis of variance and pair-wise multiple comparisons were done using the Holm-Sidak method. Results: The etch-and-rinse adhesive and two bottle self-etch system showed significantly higher bond strength than the single bottle self-etch system. Caries excavation method had no influence on bond strength values. Conclusions: Carisolv ® did not affect the microtensile bond strength values of different adhesive systems tested to the caries affected dentine.

Aim:The purpose of the present study was to comparatively evaluate the effect of presence of a 2 mm ferrule and different type of dowels on fracture resistance of mandibular premolars.Materials and Methods:Fifty uniradicular mandibular premolars were divided into five groups (n = 10). Ten teeth received no treatment (group I). Samples in group II & III were decoronated 2 mm above cemento-enamel junction and received custom cast dowel-core and fiber dowel-composite core respectively, with 2 mm ferrule. Samples in group IV & V were decoronated at CEJ and were restored using cast dowels and fiber dowel-composite cores, without any ferrule. The restored teeth received metal ceramic crowns and were mechanically loaded. The specimens were subjected to a static load, until fracture, to determine the fracture resistance and fracture mode.Results:The samples with 2 mm ferrule had a higher fracture resistance than non ferrule groups. Within non ferrule groups, there were no significant differences in the fracture resistance. Specimen restored with cast dowel had more incidence of non-repairable fracture.Conclusions:Presence of ferrule increased the fracture resistance of endodontically treated teeth. In case of absence of ferrule, fiber dowels had similar fracture resistance as that of cast dowels and showed increased incidence of repairable fracture.

Group 4 showed significant less amount of dye penetration as compared with other groups.

The electronic method for determining the working length of root canal was found to be more accurate than the radiographic method.