Background: Knowledge of tooth morphology is obligatory for achieving success in dental treatment. The root canal configuration of maxillary first premolar (MFP) has been shown to be highly varying. The study was conducted to assess the canal configurations in the roots of upper first premolars within a sample population of Peshawar with the help of tooth cross-sectioning method. Methods: The extracted 250 maxillary first premolars had undergone access cavity preparation after cleaning and pulp was removed from each individual tooth. The root canals were located in the pulp chamber floor and then India ink was injected in to their orifices. When the canals get stained the roots were cross-sectioned at three levels to assess the configurations of root canals using a categorization method devised by Weine. SPSS version 19 was used to analyze the data. A p-value of less than 0.05 was considered statistically significant. Results: Among 250 maxillary first premolars, the common root canal configuration was Weine's type-IV in 30.4% and type-III in 30.0% teeth. Weine's type-I and type-II were observed in 24.8% and 8.8% premolars, respectively. Variable root canal configurations were seen in 6.0% teeth. Apical delta was found in 1 (0.4%) tooth. A highly statistically significant difference was observed when root canal configuration was compared with external root morphology. Conclusion: Weine's type-IV and type-III root canal configurations were frequently observed in maxillary first bicuspids.

Background: The Cusp of Carabelli is a small additional cusp which is situated on the mesiopalatal surface of first maxillary molars. This nonfunctional cusp comes in many forms including furrows, ridges or pits and is collectively known as the Carabelli trait Objective: To evaluate the frequency of the occlusal contacts between the accessory cusp of Carabelli and the opposing arch tooth among both genders in patients attending the out-patients department of Peshawar Dental Hospital, Peshawar Methodology: This descriptive cross-sectional study was conducted on 300 subjects visiting the OPD of Peshawar Dental Hospital from October 2022 to December 2022. The sample size was calculated using WHO formula N=p(100-p)z2/d2 (Http://www.fao.orgThe age group selected for the participants was from 13-30 years. Consecutive sampling technique was used.). Articulating paper was used to assess the occlusal contacts caused by the cusp of Carabelli. The data were analyzed using SPSS version 20. Pearson’s chi square test was applied to analyze the data. P value of ≤ 0.05 was considered statistically significant. Results: The results of the current study showed that 10.7% of the participants experienced occlusal contacts caused by the presence of their accessory cusp with the opposing arch tooth with no statistically significant difference between genders. Conclusion: The cusp of Carabelli is the most prevailing variation found on the palatal aspect of mesiopalatal cusp of permanent maxillary first molars in a hospital-based inhabitants of Peshawar with rare occlusal contacts experienced by the patients. Key words: Cusp of Carabelli, Maxillary permanent first molars, Occlusal contact.