Determining the localization of premolar zenith positions according to the gingival line.

BACKGROUND The gingival zenith (GZ) positions according to a reference line in the premolar (PM) area remain concern, especially for the clinicians in placing the gingival contours during surgery. OBJECTIVES The objectives of this study are to determine the maxillary PM GZ positions according to GZ line (GZL). MATERIALS AND METHODS A sample population of 63 patients with healthy gingival tissue was studied. The GZ was determined at the most apical point of the gingival marginal scallop. A horizontal-zenith line (ZL) was drawn connecting the GZ from the ipsilateral canine (C) and central incisor teeth. Reference lines were drawn, and bilateral measurements were taken in the respective stone casts in the PM area. RESULTS No statistically significant differences were found between bilateral first premolars (FPM) and second premolars (SPM). When considering ipsilateral FPM and SPM, statistically significant differences were found between them. For all PM teeth, the mean distance value of GZ to GZL was approximately 1.32 mm. CONCLUSIONS The present study results showed that GZs of FPM and SPM teeth for both left and right sight was coronally located according to ZL.