Thesis (Ph.D.) - Cairo University - Faculty of Oral and Dental Medicine - Department of Oral (Radiology and Diognosis)

Aim: This study was conducted to assess the variations in the number of roots, root canals and root canal configurations in the permanent maxillary premolars and the relationship between their roots apices and the maxillary sinus floor in a sample of Egyptian population. Methodology: A total of 216 upper first premolars and 232 upper second premolars were examined from 128 CBCT scans. Gender of the patient was registered for each scan. The teeth were investigated in terms of the number of roots and root canals and the canal configuration according to Vertucci classification while the proximity between their roots apices and the maxillary sinus floor (MSF) was determined according to Kilic classification. Results: Most of the maxillary first premolars were double rooted (69.9%) with two root canals 92.6 %, while the majority of the maxillary second premolars were single rooted (74.6%) with two root canals as well (79.3%). The prevalence of third root was rare in both maxillary bicuspids (3.7% in 1st premolars and 0.4% in maxillary 2nd ones). Type I root canal configuration showed the highest prevalence in double and triple-rooted maxillary premolars, while single rooted ones showed diversity in root canal configurations. Regarding the relationship between premolars roots tips and the MSF, most of the maxillary 1st premolars had no relationship with the MSF followed by type 3. On the other hand, type 2 was the most prevalent position in maxillary 2nd premolars, followed by type3.Concerning gender, males showed two and three roots and root canals more than females. Additionally, males showed a higher incidence of Type 1, Type 2 sinus relations than females

Issued also as CD