Partial-thickness/Non-advanced vs. Full-thickness/MCAT Tunnelling for the Treatment of Multiple Gingival Recessions

Study Overview
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Brief Summary
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Included patients will be randomly allocated to the test (split-thickness non-advanced tunnel - Zabalegui et al. 1999) or to the control group (full-thickness coronally-advanced tunnel - MCAT - Aroca et al. 2010).

Detailed Description
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Design: Randomized, clinical, outcome-assessor blinded, multi-centric, superiority trial with two parallel groups and a 1:1 allocation ratio. The follow-up of individual patients will be 6 months (to be extended to 3/5 years if funding will be available) Patients with a minimum of two-adjacent teeth with RT1 and/or RT2 gingival recessions (at least one with a depth >2 mm) with indication for root coverage treatment will be included. RT2 gingival recessions will be considered not eligible when associated with interproximal exposure of the CEJ. Mean root coverage (linear) at 6-months will be evaluated as the primary outcome by a blinded outcome assessor.

Official Title
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Partial-thickness/Non-advanced vs. Full-thickness/MCAT Tunnelling for the Treatment of Multiple Gingival Recessions: a Multi-centre Randomized Clinical Trial

Conditions
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Gingival Recession

Intervention / Treatment
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* Procedure: Split-thickness non-advanced tunnel (Zabalegui et al. 1999)
* Procedure: Full-thickness coronally-advanced tunnel (Aroca et al. 2010)


Participation Criteria
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Eligibility Criteria
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Any patient having a minimum of two adjacent teeth with RT1 and/or RT2 gingival recessions (at least one with a depth >2 mm) with indication for root coverage treatment, being at least 18 years old and able and agreeing to sign a written informed consent form will be potentially eligible for this trial. RT2 gingival recessions will be considered not eligible when associated with interproximal exposure of the CEJ (interdental gingival recession). In case of multiple RT1/RT2 recessions involving 2 or 3 teeth, at least 2 or 1 more non-included adjacent teeth should respectively be present in order to guarantee a minimum of 4 adjacent teeth (including the included ones) in the region of interest (ROI) for digital scanning. Patients fitting to all the inclusion criteria as above will be not included in the study if they appear to be unable to attend to the study-related procedures (including the follow-up visits) or if one or more of the following systemic or local exclusion criteria are found in the enrollment phase. Systemic primary exclusion criteria: Compromised general health which contraindicates the study procedures (ASA IV-VI patients); Systemic diseases/medications which could influence the outcome of the therapy (e.g., uncontrolled diabetes mellitus); Current smokers (self-reported, any type of smoking), users of chewing tobacco, and drug/alcohol abusers; Pregnant or nursing women; Local primary exclusion criteria: History of previous periodontal surgery (mucogingival or other) on the teeth to be included; Patients having had surgical soft tissue augmentation procedures in the ROI within the previous 12 months; Furcation involvement in the teeth to be included; Presence of severe tooth malposition, rotation or clinically significant super-eruption in the teeth to be treated; Presence of fixed or removable prosthesis in the area to be treated; Presence of RT3 gingival recessions in the same surgical area of the treatment. Secondary exclusion criteria (after initial therapy is provided): Not able to achieve good oral hygiene and control gingivitis in the whole of the dentition (FMPS < 20% and FMBS < 20%); Persistence of uncorrected gingival trauma from toothbrushing.
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
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Split-thickness non-advanced tunnel (Zabalegui et al. 1999)<br> | Procedure: Split-thickness non-advanced tunnel (Zabalegui et al. 1999)<br>* A split-thickness non-advanced tunnel will be performed according to Zabalegui et al. (1999).<br>|
| Active Comparator: Full-thickness coronally-advanced tunnel (Aroca et al. 2010)<br>Modified Coronally Advanced Tunnel (MCAT) | Procedure: Full-thickness coronally-advanced tunnel (Aroca et al. 2010)<br>* A full-thickness coronally-advanced tunnel (Modified Coronally Advanced Tunnel - MCAT) will be performed according to Aroca et al. (2010).<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mean Root Coverage (MRC) (6 months) | Defined as the percentage of root coverage in the mid-buccal aspect obtained with respect to baseline. The MRC will be measured as a percentage (% mm, with probe) 6 months after surgery. Considering the study will also include RT2 gingival recessions (we expect CRC not possible in some cases), the linear 6 months MRC will be evaluated as the primary outcome of the study. | 6 months after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mean Root Coverage (MRC) (3 months) | Defined as the percentage of root coverage in the mid-buccal aspect obtained with respect to baseline. The MRC will be measured as a percentage (% mm, with probe) 3 months after surgery. | 3 months after surgery | 
| Complete Root Coverage (CRC) | Defined as the presence/absence of complete root coverage in the mid-buccal aspect. It will be measured at 3- and 6-months after surgery and evaluated as linear mid-buccal measurement (mm, with probe). | 3 and 6 months after surgery | 
| Recession Reduction (RR) | Defined as the reduction in recession in the mid-buccal aspect with respect to baseline. It will be calculated at 3- and 6-months after surgery and evaluated as linear mid-buccal measurement (mm, with probe). | 3 and 6 months after surgery | 
| Contact-point/Papilla-tip (DCP) distance changes | Defined as the change in the linear distance between the contact point and the top of papilla at the mesial aspect of each tooth (Aroca et al. 2010) with respect to baseline. It will be measured at 3- and 6-months after surgery and evaluated as linear measurement (mm, with probe). | 3 and 6 months after surgery | 
| Keratinized Tissue Height (KTH) changes | Defined as the linear changes in mid-buccal keratinized tissue height (distance from the gingival margin and the mucogingival junction) with respect to baseline. It will be calculated at 3- and 6-months after surgery and evaluated as linear mid-buccal measurement (mm, with probe). | 3 and 6 months after surgery | 
| Probing Pocket Depth (PPD) changes | Defined as the changes in PPD (distance from the gingival margin to the bottom of the probeable sulcus) with respect to baseline. It will be calculated at 3- and 6-months after surgery and evaluated only as linear mid-buccal measurement (mm, with probe). | 3 and 6 months after surgery | 
| Clinical Attachment Level (CAL) changes | Defined as the changes in CAL (distance from the CEJ to the bottom of the probeable sulcus) with respect to baseline. It will be calculated at 3- and 6-months after surgery and evaluated only as linear mid-buccal measurement (mm, with probe). | 3 and 6 months after surgery | 
| Dental hypersensitivity (DH) | Assessed by 10 s air spray applied to the buccal cervical area. It will be evaluated at baseline and at 3- and 6-months after surgery. | 3 and 6 months after surgery | 
| Root-coverage Esthetic Score (RES) | Evaluated at 3- and 6-months according to Cairo et al. (2009). | 3 and 6 months after surgery | 
| Digital Mean Root Coverage (dMRC) | Defined as the percentage of root surface coverage obtained with respect to baseline. The sMRC will be measured at 3- and 6-months after surgery. It will be assessed as buccal surface measurement (% mm2, digital assessment). | 3 and 6 months after surgery | 
| Digital Complete Root Coverage (dCRC) | Defined as the presence/absence of complete root surface coverage. It will be measured at 3- and 6-months after surgery and evaluated as buccal surface measurement (mm2, digital assessment). | 3 and 6 months after surgery | 
| Digital Recession Reduction (dRR) | Defined as the reduction in recession surface with respect to baseline. It will be calculated at 3- and 6-months after surgery and evaluated as buccal surface measurement (mm2, digital assessment). | 3 and 6 months after surgery | 
| Digital Contact-point/Papilla-tip (dDCP) distance changes | Defined as the changes in the area between the contact point and the top of papilla at the mesial aspect of each tooth with respect to baseline. It will be measured at 3- and 6-months after surgery and evaluated as area measurement (mm2, digital assessment). | 3 and 6 months after surgery | 
| Digital Gingival thickness (dGT) | It will be measured both at the gingival margin and 1-mm apically. It will be assessed as a mid-buccal thickness measurement (mm, digital assessment) at 3- and 6-months after surgery. | 3 and 6 months after surgery | 
| Digital Keratinized Tissue Height (dKTH) changes | Defined as the changes in keratinized tissue surface (surface delimited apico-coronally by the gingival margin and the mucogingival junction and mesio-distally by the projection of a line passing by the contact-point and perpendicular to the occlusal aspect of each tooth) with respect to baseline. It will be calculated at 3- and 6-months after surgery and evaluated as buccal surface measurement (mm2, digital assessment). | 3 and 6 months after surgery |