Journal of Dentistry, Shiraz University of Medical Sciences
Volume:14 Issue: 2, Jun 2013

tatement of Problem: The most common method for parotid duct anastomosis is suturing. A ductal defect of greater than 1cm may prevent a direct anastomosis. The goal of this study was a sialographic evaluation to compare repairing a parotid duct with facial vein graft versus Gore-Tex tub in 19 dogs. Nineteen dogs were studied in this experimental trial. Extra oral transverse incisions were made in buccal regions bilaterally to expose parotid ducts and a defect (2 cm) was performed in similar areas (right and left). The right resected duct was repaired with facial vein graft and the left anastomosis was performed by using the Gore-Tex tube microscopically. Sialography was used to evaluate the ductal leakage. Statistical analysis was performed, using SPSS software and McNemar’s test. Based on the sialography evaluation; the ductal leakage was seen in five cases (26.31%) on the right side and in seven cases (36.84%) in the left side. Statistical analysis using McNemar’s test suggested no statistically significant difference between ductal leakages in right and left parotid ducts (p> 0.05). The results of this study suggest that the efficacies of Gore-Tex tube and vein graft in parotid duct anastomosis are similar, but the use of Gore-Tex tube had a number of advantages, including reduced morbidity of the graft and short operation time.

Statement of Problem: For a luting agent to allow complete seating of prosthetic restorations, it must obtain an appropriate flow rate maintaining a minimum film thickness. The performance of recently- introduced luting agents in this regard has not been evaluated. To measure and compare the film thickness and flow properties of seven resin-containing luting cements at different temperatures (37°C, 25°C and10°C). Specimens were prepared from five resin luting cements; seT (SDI), Panavia F (Kuraray), Varioloink II (Ivoclar), Maxcem (Kerr), Nexus2 (Kerr) and two resin-modified glass-ionomer luting cements (RM-GICs); GC Fuji Plus (GC Corporation), and RelyX Luting 2 (3 M/ESPE). The film thickness and flow rate of each cement (n=15) was determined using the test described in ISO at three different temperatures. There was a linear correlation between film thickness and flow rate for most of the materials. Cooling increased fluidity of almost all materials while the effect of temperature on film thickness was material- dependent. At 37°C, all products revealed a film thickness of less than 25µm except for GC Fuji Plus. At 25°C, all cements produced a film thickness of less than 27 µm except for seT. At 10°C, apart from seT and Rely X Luting 2, the remaining cements showed a film thickness smaller than 20 µm. Cooling increased fluidity of almost all materials, however. the film thickness did not exceed 35 µm in either condition, in spite of the lowest film thickness being demonstrated at the lowest temperature.

Statement of Problems: An ideal antimicrobial agent should have minimal cytotoxic effect to host cells. The aim of this study was to determine the cytotoxic effect of three commercial mouthwashes (Chlorhexidine, Persica and Irsha) on the cultured fibroblasts. For determining the cytotoxic effect of Irsha, Chlorhexidine and Persica, uninfected cells were grown in the absence and presence of various concentration (2,4,8,16,32,64,128) of these mouth washes for 1, 2, 3 and 4 days. In this study, three mouth washes show cytotoxic effect on the cultured cells, at commercially available concentration and even diluted and Irsha was found to be the most toxic one. Cytotoxicity of three mouthwashes was reduced with decreasing concentration. Our results showed that all three solutions were toxic to the cultured fibroblast. Other studies which investigate their clinical effect are recommended.

Statement of Problem: Oral premedication used to reduce the anxiety in patients undergoing dental treatment. Passion flower has been used as a sedative that can control the dental anxiety. This study determines the efficacy of Passion flower, in reducing anxiety during the dental procedures. In this randomized- one sided blind clinical trial, 63 patients, with moderate, high and severe anxiety(according to VAS score) in need of periodontal treatment were randomly divided into 3 groups of 21.The first group was given the drop Passion flower drop and the second group were given the drop of placebo and the third group; neither drug nor placebo were given (negative control group). Results were analyzed by Chi Square, Variance Analysis, Tucky and Paired-T using SPSS software. Mean anxiety level prior to the drug administration was 12.09±2.42 for the Passion flower group, 12.00±2.66 for the placebo group and 11.66±2.39 for the negative control group. After premedication, these values were: 8.47±2.58 for the Passion flower group, 10.52±2.11 for the placebo group and 11.23±2.34 for the negative control group. These results demonstrated a significant difference (p< 0.0001) in the anxiety levels before and after the Passion flower administration in the Passion flower group and also between the Passion flower group and the other two groups. Results indicated that administration of Passion flower, as a premedication, is significantly effective in reducing the anxiety. Since this study is a pioneer on the subject, further trials with greater number of subjects are required to confirm our results.

Statement of Problem: Laser irradiation makes structural and chemical changes on the dental hard tissues. These changes alter the level of solubility and permeability of dentin. The aim of this study was to compare the microhardness and the structural changes in the dentin cavity floor prepared with Er: YAG laser and bur. In this experimental study, fifteen intact human molars were selected. Two square cavities were prepared on the buccal and lingual surfaces of each tooth. One side was randomly prepared by Er:YAG laser and the other side by bur. The specimens were divided into two halves. Consequently, there were 30 samples in every group. One half was assigned for the Vickers’s hardness test and the other one, for determination of Ca and P percentage and atomic elements analysis. The data were analyzed by Paired T-tests through SPSS16 (α≤o.o5). The means and the standard deviation of the microhardness were 69.77±25.62 and 51.33±9.31 Kg/mm2 in the laser and bur groups, respectively. Statistical analysis showed significant differences between the two groups (p=0.017). Weight percentage of calcium in the laser cavity (65.5) was less than the bur cavities (68.21) and the difference was significant (p= 0.037). The hardness of dentin in laser group was higher than the bur group because of the higher mineral content of the dentin. The hardness and the mineral content of dentin are important factors in the bonding effectiveness of the dental materials so with laser cavity preparation, good mineral substrate are available for a better bonding.

Statement of Problem: The knowledge of the pulp anatomy plays an important role in the success of endodontic treatments. The aim of this study was to determine the root and canal morphology of the mandibular second molar teeth in an Iranian population. One hundred intact human mandibular second molars were collected. The teeth were examined visually and the number of their roots were recorded. The teeth were covered using of lacquer. Access cavities were prepared and the pulp tissue was dissolved by sodium hypochlorite. The apices were covered with the glue and the root canals were injected with the methylene blue and were decalcified with 10% nitric acid, dehydrated with ascending concentrations of alcohol and rendered clear by immersion in methyl salicylate. The following remarks were evaluated: (i) number of root canals per tooth; (ii) number of canals per root; (iii) canal configuration in each root. Of 100 examined teeth; 6% had one root, 89% had two roots, 2% had three roots and 3% had C-shaped roots. The teeth were classified based on the number of canals: 3 % had single canal, 6 % two canals, 54% three canals, 34% four canals, whilst 3 % had C-shaped roots. Based on the Vertucci classification, the most prevalent canal configuration in the mesial root was type II and in the distal root was type I. Iranian mandibular second molar teeth exhibit features which are similar to the average Jordanian, Caucasian and Burmese root and canal morphology.

The present study, as a pilot study, aimed to investigate the increase in the intercanine width in different facial forms to predict the amount of future increase in the intercanine width. The results of the pilot study showed that the intercanine width increased more in the boys with wider faces while this relationship was not observed in the girls. Based on the results of this preliminary study, the girls’ facial width could not be considered as a determining criterion in evaluation of the amount of increase in the intercanine width.

There is a great challenge in the treatment of deeply fractured and un-restorable teeth among dentists. Orthodontic force eruption is a method of treatment for these teeth to preserve natural root system and periodontal structures. This technical report is a new modification of this procedure presented in an 11- year old boy with deeply fractured left second mandibular incisor. The fractured teeth were treated with root canal therapy and a file #80 was modified to become a hook cemented into the fractured tooth. Anterior teeth were splinted and used as anchorage to help the root extrusion. 1-year follow up of the tooth showed the convenience of the treatment. This simple and low-cost method can be an acceptable alternative to the current high cost techniques, achieving the same results.

Variations of dental root canals were reported by different authors. One of the rare variations is the presence of two separate palatal roots of maxillary molars, especially second maxillary molars. This case study reported a maxillary second molar with two separate palatal roots and a palatal bifurcation which was found during the periodontal flap surgery. Although these variations are rare, awareness of their presence would help in successful periodontal and endodontic treatment.