Influences of Gingival Cord Retractor in Retention Rate of Non-carious Cervical Lesions Restorations.

Study Overview
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Brief Summary
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The aim of this study is through a randomized clinical trial, double blind, splith-mouth, evaluate the retention rate of restorative protocols of Non-carious cervical lesion. The presence of gingival displacement with a retraction cord (yes or no) and the category of adhesive system (etch-and-rise and self-etching) will be evaluated. Data will be collected, tabulated and submitted to statistical analysis.

Detailed Description
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Cervical wear is classified as a noncarious cervical lesion (NCCL), which is a pathological process characterized by loss of dental hard tissues near the cementoenamel junction (CEJ). The aim of this study is through a randomized clinical trial, double blind, splith-mouth, evaluate the retention rate of restorative protocols of Non-carious cervical lesion. The presence of gingival displacement with a retraction cord and the category of adhesive system will be evaluated. Two hundred and twenty teeth, with NCCL of depth greater than 1.5mm, of 55 healthy patients of both sexes will be select. The teeth will be randomly divided into 4 different groups according to the gingival displacement with retraction cord (yes or no) and adhesive system category (etch-and-rise and self-etching). Data will be collected, tabulated and submitted to statistical analysis.

Official Title
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Influences of Gingival Cord Retractor in Retention Rate of Non-carious Cervical Lesions Restorations With Different Adhesive Systems. Randomized Clinical Trials.

Conditions
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Dental Wear, Tooth Wear

Intervention / Treatment
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* Procedure: Gingival displacement
* Procedure: Enamel and dentin etched
* Procedure: Selective enamel etched
* Procedure: Wash and dry
* Device: Total-etch adhesive system
* Device: self-conditioning adhesive system
* Procedure: Photoactivated


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Healthy volunteers; both genres; presence of at least four non carious cervical lesions of similar dimensions in the same arc and opposite quadrants; good oral hygiene. Exclusion Criteria: Presence of cavities, cracks or enamel fractures; extensive or unsatisfactory restorations; recent restorations involving the labial surface; dentures or orthodontics; presence of periodontal disease and,or parafunctional habits; systemic disease and, or severe psychological; constant use of analgesic and, or anti-inflammatory or allergic response to dental products.
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: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Retraction and total-etch<br>Gingival displacement with a gingival cord (#0, #00 or #000) prior to the restoration. Application of total-etch adhesive system: enamel and dentin etched with 35% phosphoric acid, wash, dry, two layers of primer/bond application with a brush and photoactivated for 20 seconds. | Procedure: Gingival displacement<br>* Gingival displacement with a gingival cord (#0, #00 or #000) with specific spatula.<br>Procedure: Enamel and dentin etched<br>* Enamel and dentin etched with 35% phosphoric acid for 30 and 15 seconds, respectively.<br>Procedure: Wash and dry<br>* Wash and dry with absorbent paper.<br>Device: Total-etch adhesive system<br>* Two layers of pirmer/bond on enamel and dentin with a brush.<br>Procedure: Photoactivated<br>* Photoactivated for 20 seconds<br>|
| Active Comparator: No retraction and total-etch<br>Application of total-etch adhesive system: enamel and dentin etched with 35% phosphoric acid, wash, dry, two layers of primer/bond application with a brush and photoactivated for 20 seconds. | Procedure: Enamel and dentin etched<br>* Enamel and dentin etched with 35% phosphoric acid for 30 and 15 seconds, respectively.<br>Procedure: Wash and dry<br>* Wash and dry with absorbent paper.<br>Device: Total-etch adhesive system<br>* Two layers of pirmer/bond on enamel and dentin with a brush.<br>Procedure: Photoactivated<br>* Photoactivated for 20 seconds<br>|
| Active Comparator: Retraction and self-conditioning<br>Gingival displacement with a gingival cord (#0, #00 or #000) prior to the restoration. Application of self-conditioning adhesive system: selective enamel etched with 35% phosphoric acid, wash, dry, one layer of acid/pirmer on enamel and dentin with a brush, one layer of bond with a brush and photoactivated for 20 seconds. | Procedure: Gingival displacement<br>* Gingival displacement with a gingival cord (#0, #00 or #000) with specific spatula.<br>Procedure: Selective enamel etched<br>* Selective enamel etched with 35% phosphoric acid for 15 seconds.<br>Procedure: Wash and dry<br>* Wash and dry with absorbent paper.<br>Device: self-conditioning adhesive system<br>* One layer of acid/pirmer on enamel and dentin with a brush following to one layer of bond with a brush.<br>Procedure: Photoactivated<br>* Photoactivated for 20 seconds<br>|
| Active Comparator: No retraction and self-conditioning<br>Application of self-conditioning adhesive system: selective enamel etched with 35% phosphoric acid, wash, dry, one layer of acid/pirmer on enamel and dentin with a brush, one layer of bond with a brush and photoactivated for 20 seconds. | Procedure: Selective enamel etched<br>* Selective enamel etched with 35% phosphoric acid for 15 seconds.<br>Procedure: Wash and dry<br>* Wash and dry with absorbent paper.<br>Device: self-conditioning adhesive system<br>* One layer of acid/pirmer on enamel and dentin with a brush following to one layer of bond with a brush.<br>Procedure: Photoactivated<br>* Photoactivated for 20 seconds<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Success rate of noncarious cervical lesions restorations according to the World Dental Federation criterion | Evaluate the success rate of NCCL restoration with a 36 mounths follow up | 36 mounths |