Gross Anatomy and Histology of First Premolar Teeth in Baghdad Population

Abstract

Introduction: Dental anatomy involves the study of the morphology, growth, identity, and function of each tooth in human dentition. This study evaluates the descriptive anatomy, histology, and geometry of the human first premolars in both jaws to enhance dental care quality. Various techniques, including in vivo and in vitro methods, have been employed to study root and root canal morphology.
Methodology:A total of 51 sound teeth were collected from Ghazi Al-Hariri Hospital for Surgical Specialties and Al-Amiria Specialized Dental Center. These teeth, extracted due to orthodontic procedures, belonged to individuals aged 20-40 years and were collected from November 2023 to April 2024.
Results:The study found that double-rooted teeth were predominantly present in the maxillary first premolars, while single-rooted teeth were more common in the mandibular first premolars. In the histological analysis, acellular cementum was observed at the cementoenamel junction (CEJ) and the coronal one-third of the root, whereas more cellular cementum was present in the apical two-thirds of the tooth. The radicular dentin adjacent to the cementodentinal junction exhibited Tomes’ Granular Layer. Dentinal tubules were present throughout the dentin thickness. The pulp showed four zones: odontogenic, cell-free, cell-rich, and pulp.
Conclusion:There  was  a  morphometric  variation  between  upper  and  lower  first premolars, with no differences observed in histological sectioning