---

  Background & Objectives: Vast usage of Amalgam and it's poisoning nature related to mercury necessited the hygiene aspects of mercury to be put in to consideration. The aim of this study was to assess knowledge, attitude and practice of dentists towards the principles of mercury hygiene.

  Methods : In this descriptive analytic study, 116 dentists in their private clinic were selected randomly and were analyzed for the above parameters by questionnaire. Data were analyzed in spss.14/win software with descriptive statistic methods, t test and Pearson correlation test.

  Results : The mean of knowledge, attitude and practice of dentists were 45.74±13.28, 68.96±10.62 and 17.43±17.55 respectively. There was no statistically significant correlation between the knowledge and attitude and practice of principles of mercury hygiene. Besides there was no significant correlation between sex, specialty and graduation time with those parameters.

  Conclusion: Despite positive attitude and knowledge, practice of Tabriz dentists is not favorable. According to the positive attitude and the willingness of the dentists for knowledge enhancement and optimizing the practice for mercury hygiene, appropriate programming for mercury hygiene instruction during the educational period and continuing educational program can be very advantageous.

---

Background & objectives: Type 2 diabetes mellitus (DM) is a metabolic disorder that is common throughout the world. Meta-analysis is a statistical technique in which the results of two or more independent studies, with similar objectives, are mathematically combined in order to improve the reliability of the results. The aim of this study was to compare the efficacy of metformin and linagliptin in patients with type 2 diabetes.
Methods: To identify relevant studies, PubMed, ISI Web of Science, Embase, Cochran library, Scopus and Ovid databases were searched from January 2000 to August 2016. Mean difference (MD) with 95% confidence interval (CI) for efficacy were calculated and pooled analysis was performed using Stata V.12 and RevMan V.5.3 software.
Results: Four studies recruiting1260 patients with DM (682 patients in group linagliptin and 578 patients in metformin group) were included in this study. The MD of HbA1C outcome of 0.5 mg linagliptin was effective (0. 7295, % CI = 0. 69 - 0. 75). The MD of fasting blood sugar (FBS) test revealed that linagliptin was effective at 0.5mg (MD = 36.79, 95% CI = 35.20 - 38.38) and 5 mg (MD = 12.65, 95% CI = 2.68 to 22.63) doses.
Conclusion: Our results suggest that some doses of linagliptin versus metformin may be an effective treatment for DM2. However, the number of studies was limited, and further research is needed.