Morphometric study on single-root premolars in a European population sample: An update on lengths and diameters

External dental root morphology knowledge is fundamental for the implication in periodontal and implant dentistry branches. So far the literature available presents a few and not updated studies regarding this particular topic. The aim of this study is to investigate the morphometry of external gross anatomy of single-rooted premolars, focusing on length and tapering parameters. One hundred seventy four extracted teeth of European origin were used to measure the root length and diameter on the 4 radicular surfaces, starting from the cement- enamel junction to the root apex. Data were statistically analyzed with descriptive measures and any statistical significance (p value <0.05) was evaluated by means of T-student test. The length of the single-root mandibular and maxillary premolars resulted to be higher than those reported in literature. The data regarding the tapering showed a pronounced lowering of the diameter root from the middle point of the root. In addition, the single-rooted premolar showed to own an oval-shaped root characterized, in both arches, by a high variability, confirming the data reported in literature. The present morphometric study providing analytical data regarding the length, the tapering and the high variability of the single-root premolar highlights the need of an accurate knowledge of the root anatomy for a correct therapeutic approach in the daily clinical practice.