Accuracy of Guided Dual Technique in Esthetic Crown Lengthening: A Prospective Case-Series Study

Abstract

Objective: This study aimed to evaluate the efficacy and safety of a digitally guided dual technique during esthetic crown lengthening surgery. In addition, patient satisfaction and patient-reported outcomes were assessed.

Materials and methods: A prospective case series study was conducted. Cone-beam computed tomography and intraoral scans were used to design surgical guides, which were manufactured via 3D printing. The primary outcome was surgical accuracy, assessed by measuring the distance between the planned and final gingival margin positions using overlapping intraoral scans. Secondary outcomes included clinical crown length, gingival margin stability, pain, and patient satisfaction. Statistical analyses were performed using multilevel linear regression models, with significance set at p < 0.05.

Results: Ten participants (87 teeth) were treated without complications. The mean duration of surgery was 66.5 min. The overall absolute deviation was 0.56 mm (95% CI: 0.48 to 0.65) at 6 months postoperatively. Clinical crown length increased significantly from baseline to the end of surgery (p < 0.001), with minimal reduction at 6 months (p = 0.479). Patient-reported outcomes indicated mild postoperative pain and high satisfaction with esthetic results.

Conclusions: The digitally guided dual technique for esthetic crown lengthening surgery is safe and effective, providing highly accurate outcomes. The technique also results in excellent patient satisfaction.

Clinical significance: The use of digitally guided dual techniques for ACL surgery enhances precision and safety, leading to highly accurate outcomes and improved patient satisfaction. This approach could be beneficial in clinical settings to ensure better esthetic and functional results.

Keywords: altered passive eruption; esthetic crown lengthening; guided surgery; patient reported outcomes.

FIGURE 1

Patient's photographs before surgery. (A) Extraoral photographs, (B) intraoral photographs.

FIGURE 2

Steps for the surgical guide confection. (A) CBCT superimposed to the STL model, (B) CEJ level marked, (C) surgical guide design.

FIGURE 3

Surgical sequence. (A) Surgical guide try‐in, (B) gingivectomy, (C) soft tissue removal and check of the gingival margin position with the gingival margin, (D) gingival margin position without the surgical guide, (E) full‐thickness flap elevation, (F) checking the bone level after ostectomy, (G) suture at the end of the surgery, (H) 15 days postoperative appointment, (I) 8 weeks follow‐up appointment.

FIGURE 4

Patient's photographs at 6 months follow‐up appointment. (A) Extraoral photographs, (B) intraoral photographs.

FIGURE 5

Measurements with Real GUIDE 5 software. (A) General view, (B) CCL measurements, (C) T1 measurements, (D) T2 measurements, (E) T3 measurements, (F) overlapping of T1, T2, and T3.

FIGURE 6

Boxplot of the accuracy results by tooth type. For each box, the interior line in bold shows the median, and the edges of the box are estimates of the lower and upper quartiles. Negative values represent undercorrection (GM over the planned position) and positive values represent overcorrection (GM under the planned position).

FIGURE 7

(A) Pain experienced by the patients measured with VAS over time, (B) analgesic medication intake by the patients over time.