Objective: This study was conducted to assess the canal anatomy and morphology of the first and second mandibular premolars in the population of north Syria.Methods: One-hundred and sixty permanent fully developed apices of the mandibular premolars (95 first mandibular premolars and 65 second mandibular premolars) were collected and stored in 10% cloramine-T solution. Teeth were stained with India Ink and cleared. The number and the type of root canal were examined in the root of each cleared mandibular premolar. Results:The results showed that 82.1% of first mandibular premolars had a single canal and 17.9% contained two canals. Eighty three percent of second mandibular premolars had a single canal, 15.3% two canals, and 1.5% three canals.Conclusion: Most of mandibular premolars have a single canal with the probability of presence of two or more canals. This possibility of the existence of two or more canals in the mandibular premolars should be considered by the dentists while performing endodontic therapy.Please cite this article in press as: Habib AA, et al., Root canal configurations of the first and second mandibular premolars in the population of north Syria, Journal of Taibah University Medical Sciences (2015), http://dx.

Background: Epidemiologic studies of Oral and Maxillofacial lesions (OMLs) are rare compared with the studies of caries and periodontal diseases. It is fundamental to promote early diagnosis and provide appropriate health programs. This study was to investigate the prevalence and distribution of histologically confirmed OMLs in Sana’a.Methodology: The documented records of all patients with OMLs were recovered from the biggest histopathology laboratories that provide biopsy analysis in Sana'a Yemen, for a period of six years (2013 to 2018). This multicenter retrospective study was conducted on 1376 oral and maxillofacial biopsied lesions. The clinico-pathologic data were extracted from the histopathology reports which included age, gender, nature of specimen, site of lesion, clinical appearance and histopathological diagnosis. Descriptive analysis, Chi squared test, and binary logistic regression were performed.Results: Regarding malignant lesions, the most prevalent lesions among males and females was squamous cell carcinoma; OSCC (226; 33.0% and 214; 30.9%; respectively). Followed by undifferentiated pleomorphic sarcoma which were five cases (0.7%) for males and 6 cases (0.9%) for females. Most of the cases (43.8%) diagnosed as OSCC were in the age group older than 40 years old. At this age group, the second most prevalent lesions were Adenocarcinoma and Adenoid cystic carcinoma (0.7% and 0.6%; respectively). The results of the regression analysis show that the site of the lesion (OR; 0.6, CI; 0.51-0.81; P= 0.00) and age of the patient (OR; 4.17, CI; 5.22-5.41; P=0.00) were the independent factors of malignancy of oral lesions.Conclusion: The present study showed high prevalence of malignant and premalignant oral mucosal lesions. The data from this study highlighted the need for dental public health intervention programs for early detection of oral cancer among Yemeni population by dental practitioners. As well as the importance of education of the general population in regards to risk factors of OMLs.

Aim: the aim of the study was to assess the prevalence of impacted teeth and its association with sex and age among a sample of the Yemeni population. Materials and Methods: A cross sectional study design was employed. The study included 999 radiographical records of patients who had panoramic X-rays previously done. All radiographs were assessed for the number and type of impacted teeth, pathology-associated impaction, sex, age and location (mandible and/or maxilla). The collected data was analyzed using SPSS®version21 software. Results: The study sample comprised digital panoramic radiographs of Yemeni patients aged 17 to 54 years (mean 26.6 years). The present study found 542 patients (54.3%) presented with at least one impacted tooth. The 17 to 25 years age group of the study sample had the highest prevalence of tooth impaction (28.6%). Only 10 (1.0%) case presented pathologies associated with the impacted teeth. There was a significant difference in the number of male 203 (20.3%) and female 339 (33.9%) patients with impacted teeth (p=0.031). Impacted teeth occurred slightly more often in the mandible (42.8%) compared to the maxilla (42.4%). Conclusion: The prevalence of impacted teeth among a sample of Yemeni population was high. Third molars and canines were the most common impacted teeth. The prevalence of impacted teeth in females was higher than in males and it was higher in the mandible than in the maxilla, with the younger patients with a higher prevalence of impaction.