نشریه تحقیقات دندانپزشکی
سال سوم شماره 2 (پیاپی 4، تابستان 1393)

Ankyloglossia is a developmental anomaly of tongue which causes a deficiency in tongue mobility. This anomaly can create speech problems, periodontal diseases and orthodontic disorders. Therefore, this study aimed to determine the prevalence of ankyloglossia in 6-11 year students in Yazd.

In this desciriptive cross-sectional study conducted in 2009, 1199 male and female students were selected via cluster sampling who aged 6-11 years and studied in primary schools of Yazd. Ankyloglossia diagnosis was based on presence of short and thick lingual frenum as well as deficiency in lingual mobility . The study data were analyzed via SPSS statistical software (ver.15) applying Chi-square test.

The total prevalence of ankyloglossia among 1199 students (598 boys and 601 girls) was reported 2.5%, which was significantly higher within the boys than girls (P-value= 0.026).

The study results revealed that prevalence of ankyloglossia in students of 6-11 years in Yazd was 2.5% and as a matter of fact, it was more prevalent within boys than girls.

The external margins of restorations involve appropriate places for plaque accumulation which assist in the creation or exacerbation of periodontal disorders. Since there are different materials and techniques for restorations, the present study aimed to determine the effect of restorative materials in correct class II restorations on the gingival health in patients referring to Shahid Sadoughi Dental School of Yazd in 2013.

In this study, 60 patients were selected via convenient sampling and classified into two groups of class II restored with amalgam and composite. Four surfaces of each tooth were examined and gingival status indices, plaque, bleeding on probing and the depth of probing were applied to check the periodontal status. In order to compare the two groups statically, SPSS software (ver.16) was utilized via applying non-parametric Man-Whitney test due to the ordinal nature of the variables.

The study results demonstrated that the mean score of MGI, PI, BI and PDI indices were more in the composite restored teeth. The difference was statically significant in the level of 0.05 (P.value= 0.001). Although the mean score of PDI index was a little more in the group of composite restored teeth, there was no statically significant difference between the two groups (P.value=0.470).

The findings revealed that even correctly restored teeth have a role in causing periodontal diseases, though in this case the negative impact of composite material seems to be more than amalgam.

An association between dental treatment and Infective endocarditis (IE) incidence has been to some extent demonstrated, therefore, the appropriate prescription of the type of required drug for prophylaxis against IE is important. This study intended to evaluate dental students’ knowledge on the appropriate prescription of antibiotic prophylaxis to prevent IE in Shahid Sadoughi University of Medical Sciences in Yazd during 2013-2014.

This descriptive-analytical study was conducted on 129 fourth to sixth-year students in Faculty of Dentistry, Shahid Sadoughi University of Medical Sciences, in Yazd during 2013-2014. The samples were enrolled by census sampling method and a standard questionnaire was used comprising 15 knowledge questions on the appropriate prescription of EI antibiotic prophylaxis. In fact, it was filled out by the students as a self-administered questionnaire after they were given information on the research purposes. The obtained data were analyzed by SPSS (Version,17) using descriptive statistical tests, Mann-Whitney, Kruskal-Wallis, and Spearman Correlation Coefficient.

In this study, 65.9% (85) students were female and 34.1% (44) were male. 69.6% of the sixth-year students, 67.14% of the fifth-year students, and 62.12% of the fourth-year students revealed some knowledge on the appropriate prescription of antibiotic prophylaxis, with no significant difference among the three groups (p=0.61). Furthermore, no statistically significant difference was observed in regard with the students’ knowledge and gender (p=0.15). ), though a significant relationship was reported on the association between knowledge level and the students’ grade point average.

The study findings revealed that the highest knowledge on the appropriate prescription of antibiotic prophylaxis was observed in the sixth-year students. Hence, the process of antibiotic prophylaxis should be trained in the students’ working environment. These trainings need to be conducted as per the guidelines to decrease the risk of IE in the patients.

Geographic tongue and fissured tongue involve the most prevalent developmental tongue disorders, which allergy can be mentioned as one of its causes. Allergy is normally accompanied with different abnormalities such as mouth breathing and lymphoid hyperplasia. The purpose of this study was to assess the simultaneous occurrence of the head and neck lymphadenopathy and mouth breathing with geographic and fissured tongue.

This case control study was conducted on 190 patients referring to oral medicine department of Yazd dental school who were systemically healthy without sinusitis, taking no medication within the last month, or having any source of dental infection. The study participants were chosen via convenience sampling divided into two groups including geographic or fissured tongue patients and the control group. After filling out the consent form, all subjects were examined in regard with head and neck lymphadenopaty and mouth breathing. In order to compare the two groups, SPSS software (version, 17) was applied utilizing Chi-Square test.

In the case group, 67 subjects had head and neck lymphadenopathy. No significant difference was observed between the case and control group in presence of lymphadenopathy (P-Value= 0.317). Moreover, 18 subjects in the case group demonstrated mouth breathing. The study results revealed a significant difference between the case and control group in presence of mouth breathing (P-Value= 0.005).

The study findings revealed that regarding the significant difference in occurrence of mouth breathing, the probable symptoms of allergy should be taken into account in these patients in order to provide a timely diagnosis and treatment via frequent follow-up of such predisposed patients.

Mucous retention cyst (MRC) is the most common complication of paranasal sinuses, which rarely causes any signs or symptoms. The purpose of this study was to determine the prevalence and some associated risk factors of MRC in patients referring to the radiology department of Dental School of Shahid Sadoughi University of medical science in Yazd.

In this descriptive study, panoramic radiographs of 750 patients were continuously examined within one year in order to detect well defined, not corticated, smooth, dome-shaped radiopaque mass in maxillary sinus. In fact, MRC prevalence and its associated risk factors such as age, sex, allergy, Asthma, smoking habit and Diabetes were evaluated. In order to analyze the study data, SPSS software( version, 17) was utilized applying chi-square test.

Out of 750 examined patients, 77 patients were reported to have mucous retention cyst in their maxillary sinuses. The study results showed that these cysts were most common in patients of over 60 (P-value=0.001). Regarding the appearance of this lesion, such items as Diabetes and allergy were clearly significant (P-value=0.001, P-value=0.001). Moreover, other items such as smoking habit and asthma had an effect on this leison (P-value=0.007, P-value=0.016). On the other hand, gender did not reveal any effects on the appearance of MRC (P-value=0.057).

The findings of the present study indicated that MRC had no relation with gender, though a relationship was observed in regard with allergy, age, diabetes, smoking habit and asthma.

Impacted Third molar surgery is often associated with postoperative complications such as pain, swelling and trismus and dry socket. As the flap design is one of the factors that affect the severity of these effects, this study sought to evaluate the influence of modified triangular flap on dry socket compared to the envelop flap in patients referring to the department of oral &maxillofacial surgery at yazd dental school in 2013.

In this double-blind prospective trial, 30 patients were examined who were candidates for extraction of bilaterally impacted lower third molar with the same difficultly index referring to the department of oral &maxillofacial surgery at yazd dental school in 2013. The influence of modified triangular flap and envelop flap on dry socket was investigated seven days after the surgery. In order to analyze the difference between the two groups statistically, SPSS software (version, 17) was utilized applying fisher exact and Man-Witney tests.

This study was examined on 15 females (50%) and 15 males (50%) with an average age of 24.46±3.97. Difficulty index of the teeth was 4-7 and frequency of dry socket for envelop flap was 16.7% and for modified triangular flap it was reported 3.3%, though this difference was not statistically significant(p-value>0.05).

The findings of the present study demonstrated that the modified triangular flap design was associated with a lower incidence of dry socket.

Root canal therapy, root canal cleaning and its obturation are applied to prevent root canal reinfection. In the root canal treatment, irrigants are applied to reduce the bacteria in root canal spaces. Therefore, this study aimed to compare antimicrobial effects of chloramphenicol and sodium hypochlorite as root canal irrigants.

In this in-vitro study, after removing the crowns, 44 extracted human teeth were sterilized in autoclave and were also incubated in inoculated culture with Enterococcus faecalis for three weeks. The teeth were divided into two groups of 20 and one group of 4 (Control). Canals were then instrumentated with step back technique. Canals in group 1 were irrigated with NaOCL 5.25%, group 2 with Chloramphenicol 0.5% and group 3 with Normal Salin. Then the sample was obtained by paper cone from root canal and put in experimental tube containing BHI. The contents of tubes were cultured on plates of Blood agar. Colony forming units of bacteria were counted in 37C after 24h. The study data were analyzed via SPSS software (version,17) applying Mann-Whitney and Kruskal-wallis tests.

There was no statistically significant difference between Sodium hypochlorite and Chloramphenicol(PV=0.264) groups in regard with the mean number of the grown colonies. In fact, both groups revealed more significant antimicrobial effects than that of the control group. (PV<0.001).

Antimicrobial effect of Chloramphenicol is comparable to Sodium Hypochlorite, though more investigations are needed for its clinical application.

Self-esteem is regarded as one of the normal personality characteristics. Behavioral consequences are effective on the academic achievement and self-esteem of students. Therefore, the purpose of this study was to evaluate the relationship between university students' self-esteem and educational status at Shahid Sadoughi University of medical sciences in Yazd.

In this cross- sectional study, 257 students of different faculties of shahid Sadoughi University of medical sciences were evaluated. In order to glean the study data, a questionnaire was applied consisting of cooper-smith's self-esteem inventory as well as respondents' demographic information. The collected data were analyzed via the SPSS software(version 16) applying ANOVA and t-test.

The self –esteem mean score was reported 32.52±8.7 (with range of 0-50) and 81/3% of students had high level of self-esteem. No statistically significant relationship was detected between self-esteem and university students' educational status at Shahid Sadoughi University of Medical sciences in Yazd (p>0/05).

The study findings revealed that the majority of students had a high level of self- esteem. Furthermore, no statistically significant relationship was observed between the students' self-esteem and educational status. as a result, it seems that students' educational status have been affected by other factors.