Background: There are a few studies about the evaluation of maxillary first premolars
internal structure with micro-computed tomography (micro-CT). The aim of this study was to assess
morphological features of the pulp chamber in maxillary first premolar teeth using micro-
Methods: Extracted 15 maxillary first premolar teeth were selected from the patients who were in
different age groups. The distance between the pulp orifices, the diameter of the pulp and the
width of the pulp chamber floor were measured on the micro-CT images with the slice thickness
of 13.6 µm. The number of root canal orifices and the presence of isthmus were evaluated.
Results: The mean diameter of orifices was 0.73 mm on the buccal side while it was 0.61 mm on
palatinal side. The mean distance between pulp orifices was 2.84 mm. The mean angle between
pulp orifices was -21.53°. The mean height of pulp orifices on the buccal side was 4.32 mm while
the mean height of pulp orifices on the palatinal side was 3.56 mm. The most observed shape of
root canal orifices was flattened ribbon. No isthmus was found in specimens.
Conclusion: Minor anatomical structures can be evaluated in more detail with micro-CT. The observation
of the pulp cavity was analyzed using micro-CT.