Evaluation of Two Resin Composites and Two Adhesives for a Novel Restorative Protocol to Treat Cervical Lesions

Study Overview
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Brief Summary
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Non-carious cervical lesion is frequently associated with gingival recession, resulting in a combined lesion that has a different treatment prognosis when the two lesions appear alone. The literature presents few studies that propose a multidisciplinary approach (restorative and root coverage surgery procedures) to optimize the treatment of this combined lesion. The previously proposed approaches and materials have limitations and an optimal clinical protocol has not been established yet. Thus the aim of this study is to evaluate a novel multidisciplinary protocol with two resin composites and two different adhesive systems through a randomized clinical trial and laboratory studies. 120 combined lesions will be randomly assigned to one of the following groups: NP + TE (n = 30) - Partial restoration of cervical lesions with nanofilled composite and total-etch adhesive system and periodontal surgery for root coverage, NP + UA (n = 30) - partial restoration of cervical lesions with nanofilled composite and self-etching adhesive system and periodontal surgery for root coverage, MH + TE (n = 30) - partial restoration of cervical lesions with microhybrid composite and total-etch adhesive system and periodontal surgery for root coverage, MH + UA (n = 30) - partial restoration of cervical lesions with microhybrid composite and self-etching adhesive system and periodontal surgery for root coverage. Restorations will be assessed using the USPHS criteria after one week, six months and twelve months.

Official Title
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Evaluation of Two Resin Composites and Two Adhesives for a Novel Surgical-restorative Protocol for the Treatment of Non-carious Cervical Lesions Associated With Gingival Recession: a Randomized Controlled Clinical Trial

Conditions
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Dental Abrasion, Gingival Recession, Composite Resins

Intervention / Treatment
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* Procedure: Periodontal surgery
* Procedure: Total Etch adhesive
* Procedure: Universal Adhesive
* Procedure: Nanofilled Composite
* Procedure: Micro-Hybrid Composite


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Individuals presenting one or more combined defect, i.e. a NCCL classified as B+ (Pini-Prato et al., 2010): presenting more than 1mm in depth, affecting dental crown and root associated with Miller's class I or II gingival recession in canines or premolars with pulp vitality; Healthy patients (systemically and periodontally), 18 years old, with at least 20 teeth in occlusion; Plaque index ≤ 20% (Ainamo & Bay, 1975); NCCL cavo-surface margin without involvement of more than 50% of enamel; In tooth included in the study and the adjacent elements of the following must be observed: probing depth less than 3 mm; do not show bleeding on probing (periodontal health) and no insertion loss in the proximal and palatal areas; Provide formal consent to participate in research, after the explanation of the risks and benefits by an individual not involved in it (Resolution #196 October 1996 and the Code of Dental Professional Ethics - C.F.O. - 179/93). Exclusion Criteria: NCCL previously restored; Presence of caries; Patients with periodontitis; Patients with bruxism or teeth clenching; Patients with orthodontic treatment in progress; Pregnant patients or smokers; Patients with systemic problems (cardiovascular, blood dyscrasias, immunodeficiency, diabetes and others), which contraindicate the surgical procedure; Previous periodontal surgery in the area of interest of the present study.

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: Factorial Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Group NF + TE<br>Nanofilled Composite - Filtek Z350 XT® - 3M ESPE (NF) + Total Etch adhesive - Adper Single Bond 2® - 3M ESPE (TE) adhesive: combined lesions will be treated with partial restoration with nanofilled resin composite and total-etch adhesive system (two step). Subsequently, periodontal surgery will be performed for root coverage. | Procedure: Periodontal surgery<br>* Coronally advanced flap for root coverage<br>Procedure: Total Etch adhesive<br>* Total-etch adhesive system (two step)<br>Procedure: Nanofilled Composite<br>* Partial nanofilled-resin composite restoration<br>|
| Active Comparator: Group NF + UA<br>Nanofilled Composite - Filtek Z350 XT® - 3M ESPE (NF) + Universal Adhesive - Single Bond Universal® - 3M ESPE (UA): combined lesions will be treated with partial restoration with nanofilled resin composite and one-step self-etching adhesive system. Subsequently, periodontal surgery will be performed for root coverage. | Procedure: Periodontal surgery<br>* Coronally advanced flap for root coverage<br>Procedure: Universal Adhesive<br>* One-step self-etching adhesive system<br>Procedure: Nanofilled Composite<br>* Partial nanofilled-resin composite restoration<br>|
| Active Comparator: Group MH + TE<br>Micro-Hybrid Composite - Charisma Classic® - Heraeus Kulzer (MH) + Total Etch adhesive - Adper Single Bond 2® - 3M ESPE (TE) adhesive: combined lesions will be treated with partial restoration with micro-hybrid resin composite and total-etch adhesive system (two step). Subsequently, periodontal surgery will be performed for root coverage. | Procedure: Periodontal surgery<br>* Coronally advanced flap for root coverage<br>Procedure: Total Etch adhesive<br>* Total-etch adhesive system (two step)<br>Procedure: Micro-Hybrid Composite<br>* Partial micro-hybrid composite restoration<br>|
| Active Comparator: Group MH + UA<br>Micro-Hybrid Composite - Charisma Classic® - Heraeus Kulzer (MH) + Universal Adhesive - Single Bond Universal® - 3M ESPE (UA): combined lesions will be treated with partial restoration with micro-hybrid resin composite and one-step self-etching adhesive system. Subsequently, periodontal surgery will be performed for root coverage. | Procedure: Periodontal surgery<br>* Coronally advanced flap for root coverage<br>Procedure: Universal Adhesive<br>* One-step self-etching adhesive system<br>Procedure: Micro-Hybrid Composite<br>* Partial micro-hybrid composite restoration<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Modified United States Public Health Service (USPHS) criteria | USPHS criteria is based on the following ratings: Color compatibility, retention, marginal adaptation, anatomic form, surface texture, marginal discoloration, sensibility pre-operative and postoperative and the presence of secondary caries | 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Aesthetics (Visual Analogue Acale - VAS) | The esthetics of the treatment will be evaluated by patients´ point of view using the VAS scale | 1 year | 
| Dentin Hypersensitivity (Visual Analogue Acale - VAS) | The Dentin Hypersensitivity will be evaluated by patients´ point of view using the VAS scale | 1 year |