Esthetic Crown Lengthening With Closed Piezoelectric in Comparison to Open Flap Approach

Study Overview
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Brief Summary
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In this randomized clinical trial, the investigators are comparing two different approaches for Esthetic crown lengthening- a minimally invasive approach using piezoelectric (PZ) and a traditional open flap approach (OF).

Detailed Description
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The altered passive eruption is diagnosed when there is an excessive gingival display with short clinical crowns. Esthetic crown lengthening (ECL) is the most common surgical treatment of altered passive eruption. Traditional ECL involves osseous resection with gingivectomy or apical displaced gingiva. The amount of soft and hard tissue removal in this technique aims to provide a healthy and esthetically acceptable crown height. However, gingival tissue coronal rebound is one of the most noted post-operative complications of traditionally used techniques. On the other hand, surgical techniques that include flap reflection may cause more coronal displacement of the gingival margin. Hence, it is crucial to assess different surgical techniques to determine the most effective technique that gives the required outcomes with maximum patient satisfaction. Piezoelectric bone surgery delivers high precision in resection, good tactile sensibility, and permits a selective cut of mineralized tissue while sparing soft tissue. Further, the minimally invasive technique (mECL) was suggested to reduce pain, post-op discomfort, and procedure duration, and to accelerate the healing process. The mECL technique conveys a potential alternative approach as a sutureless, atraumatic, and less invasive technique that has been shown to increase patient satisfaction and comfort. In addition, using piezoelectric for osseous resection in this closed approach increases the favorable surgical outcomes. However, the osseous resection in mECL may be incomplete and results in a coronal rebound on the gingival contour. In addition, osseous resection in this approach is very technique sensitive to avoid root damage and uneven bone resection. A few studies and even a fewer clinical trials evaluated the clinical outcome of mECL using piezoelectric for osseous resection (PZ). Hence, in this randomized clinical trial, gingival margin and bone crest stability will be evaluated after a minimally invasive approach using piezoelectric (PZ) and a traditional open flap approach (OF).

Official Title
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Esthetic Crown Lengthening With Closed Piezoelectric in Comparison to Open Flap Approach

Conditions
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Altered Passive Eruption of Teeth

Intervention / Treatment
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* Procedure: ECL- mPZ
* Procedure: ECL-OF


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with a gummy smile due to APE (Type 1B) in two or more maxillary anterior teeth Patients with normal muscular efficiency of the upper lip Patients with no vertical skeletal defects Exclusion Criteria: Patients with systemic condition that prevent periodontal surgery Patients who smoke Patients with previous periodontal surgery in the same area Pregnant women

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Subjects' matching inclusion criteria will be randomly assigned to control (OF) or tested (PZ) groups. After eligibility has been ascertained and consent has been obtained, subjects planned for ECL will be enrolled in the study and assigned to the group in 1:1 ratio using computer-generated block randomization scheme.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Control group: Crown lengthening using a traditional open-flap approach (OF).<br>Esthetic Crown lengthening done using a traditional open-flap approach (OF). | Procedure: ECL-OF<br>* Open Flap Technique (OF): Gingivectomy and intra-sulcular incision will be carried out to remove strip of outlined marginal gingiva. Full mucoperiosteal flap will be elevated to preform ostectomy and/or osteoplasty until the desired distance achieved between the bone crest and the gingival margin. After achieving the new supracrestal distance, the flap will be sutured.<br>|
| Experimental: Test group: Crown lengthening using a minimally invasive approach by piezoelectric (PZ).<br>Esthetic Crown lengthening done using a minimally invasive approach using piezoelectric (PZ). | Procedure: ECL- mPZ<br>* Flapless Technique using Piezoelectric (PZ): Gingivectomy and intra-sulcular incision will be carried out to remove strip of outlined marginal gingiva. However, no flap will be reflected the osseous recontouring will be carried using special piezoelectric tip below gingival margin. The required distance between the bone crest and the gingival margin will be checked by inserting a periodontal probe into the incision below gingival margin.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change of supracrestal width (cementoenamel junction to alveolar crest CEJ-AC) | Change of the supracrestal width will be measured using cone beam computed tomography (CBCT). | CBCT parameter will be evaluated before the surgery and at 12 month after the surgery. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change on Probing depth (PD) | Change on Probing depth (PD) | PD will be evaluated prior to surgery and 6 and 12 month after surgery | 
| Change on Bleeding on probing (BOP) | Change on Bleeding on probing (BOP) | BOP will be evaluated prior to surgery and 6 and 12 month after surgery | 
| Change clinical attachment level (CAL). | Change on clinical attachment level (CAL). | CAL will be evaluated prior to surgery and 6 and 12 month after surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Crown lengthening, Open-flap approach, Piezoelectric approach