Caspian Journal of Dental Research
Volume:4 Issue: 1, Mar 2015

One of the main disadvantages of composites is marginal microleakage; using flowable composites as a liner beneath composite restorations has been recommended to reduce microleakage. The aim of this study was to assess the microleakage of class II restorations with different flowable composites liners. 45 extracted premolars teeth with class II cavity preparation (90 cavities) were divided into five groups and filled as follows: 1.control group: hybrid composite(Z250) 2. Z250+surefil SDR flow 3.Z250+filtek supreme xt flow composite 4.Z250+Grandio flow 5.Z250+Tetric flow. Mesial and distal cavities were filled using snowplow and layering technique, respectively. After that, the samples were immersed in 0. 5% fuchsin solution and sectioned. Gingival microleakage was then graded. Data were analyzed using Kruskal Wallis and Mann Whitney U test. There was no significant difference between the snowplow and layering methods. Microleakage of Tetric flow and Grandio flow liners was significantly higher than the control group. Other flowable composites showed no significant difference in comparison with the control group. In the present study, the results indicated that the flowable composites were not effective on reducing gingival microleakage.

Oral squamous cell carcinoma (OSCC) is one of the 10 most common malignant tumors and SCC accounts 94% of all oral malignancies. Mast cells are regarded as complex and multifunctional cells, playing a significant role in immunopathology. The aim of this study is to evaluate the number of mast cells in tissue sections of oral squamous cell carcinoma (OSCC) in comparison with normal mucosa. Sixty paraffin-embedded specimens were obtained from the archives of the Department of Oral and Maxillofacial Pathology,dental school of Babol university of medical science (15 high grade,15 low grade and 30 Iritation Fibroma). Classification of OSCC cases was according to the BRODER`S malignancy grading system. Hematoxylin and Eosin-stained slides were re-evaluated before entering the samples in our study. Toluidine blue(1%) staining was used to identify Mast cells in samples. We used SPSS software version 18 and one way ANOVA test for analyzing data. The highest mast cell count was seen in normal tissue and it was higher in low grade OSCC in comparison with high grade, but the differences between groups weren’t statistically significant. The Mean count of mast cell between OSCC and normal oral mucosa was statistically significant different(p=0.019).We didn’t observe any statistically significant difference between Mast cell counts of control group and low grade OSCC. The same result was seen between high garde and low grade OSCC. The Mean mast cell count difference between male and female groups weren’t statistically significant. The Mean mast cell count difference between high grade OSCC and control group was significant (p<0.05). According to the results, the average amount of mast cells decreased in OSCC in comparison with normal oral mucosa. It does not seem that mast cells play an important role in tumor progression, although further study is needed.

One factor affecting the degree of polymerization is the type of light-curing device. The aim of this study was to compare the effects of LED and QTH light curing units on the surface hardness of composite and compomer. In this experimental study, 30 samples of composite and compomer were divided into 3 groups of 10 each. One-half of the subgroups in each group were cured with LED and the other half with Halogen light curing units (LCUs). 49 points on the surface were marked and then the hardness of these points was measured by using Vickers hardness test. The mean hardness of composites cured by using LED was more than the Halogen group but in compomer it was reversed and this difference was statistically significant (p<0.001). Z 250 composite had the highest level of hardness and the lowest hardness was related to the Heliomolar composite and had significant difference. (p<0.001) In the present study, the results indicated that LED light curing unit had great effect on the hardness of composites but in compomer, the QTH showed a better result.

Root canal instrumentation is an important phase in root canal therapy. Since success in endodontic treatment depends on file defect and fracture, the aim of this study was to compare the evaluation of defect and fracture in rotary and reciproc files in severe curved root canals. In this experimental study, 60 mesial canals of human closed apex molars with more than 30° canal curvature were randomly divided into two groups. In first group M-two rotary files number# 15, 20, and 25 and in second group R25 reciproc file were used for filing, respectively. A ×8 magnifier was applied to evaluate the defect or fracture presence in each side and if it were observed, a new file would be replaced. Therefore, the number of prepared canals with each file and fractured or defective files and the place of fracture in root canal were recorded. Kaplan Meier curve and log rank test were done by using SPSS v.22. In rotary group, seven and two files were fractured and defected, respectively and four files were fractured and no defect was observed in reciproc group. Although the mean of the number of prepared canals until fracture or defect in rotary and reciproc groups was 3.3 and 7.06, respectively, there were no significant differences between two systems. All file’s fractures occurred in apical regions. The results showed that there was no significant difference in defects or fractures of rotary and reciproc systems. Reciproc instruments can be more effective than rotary ones because the root canal preparation in rotary instruments is longer than in reciproc system.

Feeling pain after root canal therapy has always been a major problem for patients and dentists. One of the suggested methods to manage the pain is using the prophylactic medication before treatment process. This study aimed at investigating the comparison of pretreatment with novafen versus gelofen on reducing the pain after root canal therapy. This double-blind randomized clinical trial study was conducted on 60 patients aged 18-65 who were indicated for root canal therapy. Patients were randomly assigned to receive gelofen capsules (400mg), novafen capsules (200mg) and placebo two capsules by every patient of these groups one hour prior to sampling. Pre/post-treatment pain was measured using Visual Analog Scale (VAS) before treatment and 4, 8, 12, 24 and 48 hours after treatment. Both novafen and gelofen indicated significant analgesic effect during the study period (p<0.001). Pain severity within 8 hours after treatment was significantly lower in novafen group than two other groups (p=0.03). The difference between the severity of pain did not show any association to their place of life and gender in any groups. Our findings revealed that the prophylactic novafen in comparison to gelofen had a better analgesic effect in short-term and could be a good candidate for the management of post-endodontic treatment pain.

Antioxidant agents such as cocoa could have some benefits in treatment of inflammation including periodontitis. The aim of this study was to investigate the effects of cocoa consumption on moderate chronic periodontitis. This single-blind randomized clinical trial study was performed on 40 subjects who were randomly divided into two groups. Treatment group received 30 gr dark chocolate (78% cocoa) and control group received 22. 5 gr white chocolate three times a day for 4 weeks. Saliva samples were collected from patients at baseline and t wenty-eight days after eating chocolate. Probing pocket depth (PPD)، Gingival index (GI، Silness and Loe)، Modified papillary bleeding index (MPBI، Barnett)، Clinical attachment loss (CAL) were recorded at baseline and 2nd، 4th، 6th، 8th weeks later in ramfjord teeth. Total antioxidant capacity (TAC) and lipid peroxidation of saliva were estimated by Ferric reducing antioxidant power (FRAP) and Tiuborbituric acid reactive substances (TBARS) methods. Data of clinical parameters were analyzed using t-test and repeated measures test. Biochemical parameters were analyzed using t-test. Intra-group comparison of clinical parameters demonstrated significant decrease in both groups (p<0. 0001) and inter-group comparison showed significant decrease of MPBI in treatment group، (p<0. 03). MPBI and GI were significantly decreased in treatment group compared to the control in the weeks of 4th، 6th and 8th، according t-test (GI4، P=0. 008-GI6، P=0. 008-GI8، P=0. 009)، (MPBI4، MPBI6، MPBI8، P<0. 0001). Treatment group showed the increase in FRAP، (p<0. 00001) and decrease in TBARS، (P<0. 015) which were statically significant in compare with control group. Consuming dark chocolate could increase TAC and decrease lipid peroxidation، gingival bleeding and inflammation.

Posterior composites are one of the most popular filling materials. The aim of this study was to evaluate the problems of general dentists during and after posterior composite restorations in city of Babol. In this study, data were collected using questionnaire about the problems during and after posterior composite filling. Then data were analyzed by chi square test. The highest complains of patients after posterior composite filling were related to the food impaction (33.4%), the most clinician's problem during posterior composite filling was inadequate proximal contact (37.2%) and most of dentists used pressing matrix band for proper proximal contact (31.2%). Most of dentists used incremental technique for composite filling (49.3%) and two-step total etch adhesives (68.7%) according to the manufacturer's instructions (44.2%) and applied wet polishing technique (75.6%) and major criteria for choosing composite as restorative material in posterior teeth were the ability of isolation (41.8%). Increasing the knowledge of dentists about these restorations may reduce the associated problems during and after composite filling.