Altered Passive Eruption: Crown Dimensions Before and After Periodontal Surgery

Objectives: The aim of this study was to analyze the clinical crowns dimensions of the anterior maxillary teeth in patients with APE, before and after esthetic surgical procedure.
Methods: Twelve participants diagnosed with APE type 1B were recruited for this study. Digital images of upper central incisors (CI), lateral incisors (LI) and canines (CA) were used to measure the widest mesiodistal portion and the longest inciso-cervical distance. A periodontal probe was used as reference marker for calibration. Data was collected and analyzed statistically (α=0.05). The width/length ratio was calculated at baseline and after flap surgery, which included gingivoplasty and extended osteoplasty.
Results: The mean coronal tooth width (mm) was 7.72±0.88 for CI, 5.80±1.28 for LI, and 6.80±1.11 for CA. The mean coronal tooth length (mm) before and after surgery for CI was, respectively, 8.07±1.24 versus 9.60±1.69; for LI was 6.35±0.90 versus 7.88±1.14; and for CA was 6.91±1.07 versus 8.28±1.32. Length measures from CI, LI and CA significantly increased after surgery (p<0.05). Additionally, CI length values were significantly higher from LI and CA, both before and after surgery (p<0.05). Mean coronal tooth width/length ratios before and after surgery for CI were 0.97±0.11 versus 0.82±0.12; for LI were 0.91±0.14 versus 0.74±0.12; and for CA were 0.91±0.11 versus 0.75±0.09. Width/length ratios from CI and LI significantly reduced after surgery.
Conclusions: It could be concluded that periodontal plastic surgery effectively increased crown lengthening, contributing to improve the anatomic proportions.