Effect of Increased Improve Time on Adhesive System

Study Overview
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Brief Summary
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Objective: This double-blind randomized clinical trial evaluates the influence of increased application time of a new etch-and-rinse two-step adhesive Single Link; (Angelus Dental Products Industry) applied in non-carious cervical lesions (NCCLs). Methods: A total of 221 restorations were randomly placed in 35 patients assigned in four groups to two different etch-and-rinse two-step adhesive Peak® Universal Bond (P) (Ultradent Products Ind) and Single Link (SL) (Angelus Dental Products Industry). The adhesives systems were applied on the NCCLs follows: P1 - applied according to the manufacturer's; P2X - applied for the double time; SL1 and; SL2X. The resin composite Amelogen (Ultradent) was placed incrementally. The restorations were evaluated imediataly (baseline), 6 and 12 months, using the FDI and USPHS criteria. Statistical analyses were performed using appropriate tests (=0.05).

Detailed Description
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Methods: Recruitment Patients were recruited as they seek for treatment in the clinics of Dentistry of the local university. No advertisement was made for participant recruitment. Patients were recruited in the order in which they reported for the screening session, thus forming a sample of convenience. Eligibility criteria A total of 183 participants were examined by two calibrated dental students to check if they met the inclusion and exclusion criteria. Sample size calculation The annual retention rate to one-step self-etch adhesives in NCCLs was reported to be 4.4% in a recent systematic review. Considering that this decline follow a linear trend, the overall retention rate of one-step self-etch adhesives will be approximately 78% after 5-year of clinical service. With an of 0.05, a power of 80%, and a two-sided test, the minimal sample size will be 41 restorations in each group in order to detect a difference of equivalence of 15% among the test groups. Interventions A total of 221 restorations were randomly placed in 35 patients assigned in four groups to two different etch-and-rinse two-step adhesive Peak® Universal Bond (P) (Ultradent Products Ind) and Single Link (SL) (Angelus Dental Products Industry). The adhesives systems were applied on the NCCLs follows: P1 - applied according to the manufacturer's; P2X - applied for the double time; SL1 and; SL2X. The resin composite Amelogen (Ultradent) was placed incrementally. The restorations were evaluated imediataly (baseline), 6 and 12 months, using the FDI and USPHS criteria. Statistical analyses were performed using appropriate tests (=0.05).

Official Title
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Effect of Increased Improve Time on Adhesive System: A RANDOMIZED CLINICAL TRIAL

Conditions
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Clinical Trial

Intervention / Treatment
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* Other: Peak etch-and-rinse (P1)
* Other: Peak applied for double time(P2X)
* Other: Single Link etch-and-rinse (SL1)
* Other: Single Link double time (SL2X)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Participants had to be in good general health, at least 18 years old, have an acceptable oral hygiene level, and present at least 20 teeth under occlusion, at least four NCCLs in four different teeth, these lesions had to be non-carious, non-retentive, deeper than 1 mm, and involve both the enamel and dentin of vital teeth without mobility. The cavo-surface margin could not involve more than 50% of enamel, and all lesions had cervical margins ending in dentin. Exclusion Criteria: Participants had not be in good general health, at less 18 years old, have not an acceptable oral hygiene level, and present at less 20 teeth under occlusion, at less four NCCLs in four different teeth, these lesions had not be non-carious, retentive and involve only enamel of vital teeth with mobility.

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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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: Crossover Assignment
Interventional Model Description: This was a double-blind, superiority, split-mouth randomized clinical trial. The study was carried out in the clinics of the School of Dentistry at the local University from August 2015 to August 2017.
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Peak etch-and-rinse (P1)<br>Application Mode - According to the manufacturer's instructions. | Other: Peak etch-and-rinse (P1)<br>* Application Mode - Peak Adhesive system applied according to the manufacturer's instructions.<br>* Other names: P1;|
| Experimental: Peak applied for double time(P2X)<br>Application Mode - According to the manufacturer's instructions, but for the double time. | Other: Peak applied for double time(P2X)<br>* Application Mode - Peak Adhesive system applied according to the manufacturer's instructions, but for the double time.<br>* Other names: P2X;|
| Active Comparator: Single Link etch-and-rinse (SL1)<br>Application Mode - According to the manufacturer's instructions. | Other: Single Link etch-and-rinse (SL1)<br>* Application Mode - Single Link Adhesive system applied according to the manufacturer's instructions.<br>* Other names: SL1;|
| Experimental: Single Link double time (SL2X)<br>Application Mode - According to the manufacturer's instructions, but for the double time. | Other: Single Link double time (SL2X)<br>* Application Mode - Single Link Adhesive system applied according to the manufacturer's instructions, but for the double time.<br>* Other names: SL2X;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Retention/fracture | The primary clinical endpoint was restoration retention/fracture | 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Marginal staining | restoration Marginal staining | 6 months | 
| marginal adaptation | restoration marginal adaptation | 6 months | 
| postoperative sensitivity | restoration postoperative sensitivity | 6 months | 
| recurrence of caries. | restauration recurrence of caries | 6 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Dentin adhesive; Non-carious cervical lesions; Longevity.