Effect of Shortening the Etching Time on the Clinical Performance of Resin Composite Restorations in Primary Teeth

Study Overview
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Brief Summary
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The aim of this study is to evaluate the effect of shortening the etching time on the 18-month clinical performance of resin composite restorations in primary molars after partial carious removal. This randomized clinical trial will include subjects (5-10 year-old children) selected at Pediatric Clinic of Federal University of Santa Maria. The sample will consist of 70 primary molars presenting active cavitated carious lesions (with radiographic involvement of the outer half of the dentin), located on the occlusal surface. The sample will be randomly divided into two groups according to the etching time of the dentin prior adhesive application (Adper Single Bond 2; 3M ESPE): recommend by manufacturers (15 seconds) and half-reduced etching time (7 seconds). The restorations will be clinically followed every 6 months for up to 18-month using the FDI criteria for clinical evaluation. Survival estimates for restoration longevity will be evaluated using the Kaplan-Meier method.

Detailed Description
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The aim of this study is to evaluate the effect of shortening the etching time on the 18-month clinical performance of resin composite restorations in primary molars after partial carious removal. This randomized clinical trial will include subjects (5-10 year-old children) selected at Pediatric Clinic of Federal University of Santa Maria. The sample will consist of 70 primary molars presenting active cavitated carious lesions (with radiographic involvement of the outer half of the dentin), located on the occlusal surface. The sample will be randomly divided into two groups according to the etching time of the dentin prior adhesive application (Adper Single Bond 2; 3M ESPE): applying of 35% phosphoric acid by 15 s - recommend by manufacturers and half-reduced etching time (7 s). The restorations will be clinically followed every 6 months for up to 18-month using the FDI criteria for clinical evaluation. Survival estimates for restoration longevity will be evaluated using the Kaplan-Meier method.

Official Title
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Effect of Shortening the Etching Time on the Clinical Performance of Resin Composite Restorations in Primary Teeth

Conditions
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Dental Caries

Intervention / Treatment
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* Other: Total etching time
* Other: Half-reduced etching time


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: *Active carious lesion in middle dentin limited to the occlusal surfaces of primary molars. Exclusion Criteria: Children who refuse or fail to cooperate with the completion of clinical procedure; Teeth without antagonist; Carious lesions in inner half of dentin; Presence of painful symptoms or signs of pulpal changes.

Ages Eligible for Study
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Minimum Age: 5 Years
Maximum Age: 10 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

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 |
| --- | --- |
| Other: Total etching time<br>Dentin etching (35% phosphoric acid) by time recommend by manufacturer (15 seconds) | Other: Total etching time<br>* Apply 35% phosphoric acid on dentin and enamel by 15 seconds.<br>* Other names: (dental conditioner - 35% phosphoric acid);|
| Experimental: Half-reduced etching time<br>Dentin etching (35% phosphoric acid) by 7 seconds | Other: Half-reduced etching time<br>* Apply 35% phosphoric acid on enamel by 15 seconds and dentin by 7 seconds.<br>* Other names: (dental conditioner - 35% phosphoric acid);|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Failure of restorations |  | 18 months after restorations' placement |