Effect of Nano-structured Alumina Coating on the Bond Strength of Zirconia Resin-bonded Fixed Dental Prostheses

Study Overview
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Brief Summary
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The purpose of this study is to evaluate the clinical outcome of resin-bonded fixed dental prostheses (RBFDPs) pretreated with nanostructured alumina coating (NAC). The study adopts a prospective, randomized, controlled, double-blind design contrasting the use of NAC to air-borne particle abrasion (APA) (control) as a surface pretreatment method of zirconia RBFDPs used for replacing missing central or lateral incisors. The primary outcome evaluated is the retention/survival of the zirconia RBFDPs pretreated with APA and NAC.

Detailed Description
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Zirconia resin-bonded fixed dental prostheses (RBFDPs) have been regarded as a promising minimally invasive alternative for the replacement of missing central and lateral incisors, offering several advantages to orthodontic space closure or tooth replacement with implant-supported restorations. Debonding of the zirconia RBFDPs represents the main technical complication since clinically established airborne particle abrasion (APA) of an inert zirconia surface does not always provide sufficient resin-bond strength. Further, APA can also impair the mechanical properties of zirconia restoration affecting its long-term success. Nano-structured alumina coating (NAC) presents an alternative non-invasive zirconia surface pretreatment. The aim of this randomized controlled clinical trial is to study the effect of NAC coated bonding surface of zirconia RBFDPs affecting its debonding and clinical survival rate. The study adopts a prospective, randomized, controlled, double-blind design contrasting the use of NAC to air-borne particle abrasion (APA) as a surface pretreatment method of zirconia RBFDPs. Healthy patients in need of a missing central or lateral incisor replacement are screened and rated to be eligible by two calibrated dentists. RBFDPs are randomly allocated into two groups and inserted by the same operator. The first group, where the bonding surface is pretreated with APA serves a control group. In the second group the restorations are pretreated with NAC. The participants and the operator are blinded to the group assignment in a double-blinded trial design. The primary outcome evaluated is the retention/survival of the RBFDP. Non-parametric tests and Kaplan-Meyer analysis will be used to determine differences between both study groups.

Official Title
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Effect of Nano-structured Alumina Coating on the Bond Strength of Zirconia Resin-bonded Fixed Dental Prostheses

Conditions
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Missing Incisors, Zirconia Surface Pretreatment, Children, Adults, Debonding

Intervention / Treatment
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* Other: NAC
* Other: APA


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 1. Patients with missing central or lateral incisor Exclusion Criteria: inadequate edentulous space for the pontic signs of bruxism abutment tooth with active periodontal or periapical disease inadequate enamel bonding surface of the abutment tooth inadequate interocclusal space for a retainer wing and a proximal connector pontic guidance physical or psychological disease likely to interfere with normal conduct of the study
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
Interventional Model Description: This is a single-centre, prospective, randomized, controlled, double-blind clinical trial.
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: APA<br>Air-borne particle abrasion of zirconia RBFDPs prior to bonding | Other: APA<br>* Air-borne particle abrasion of zirconia RBFDPs prior to bonding<br>|
| Experimental: NAC<br>Pretreatment of zirconia RBFDP with nanostructured alumina coating after milling of RBFDP's framework | Other: NAC<br>* Pretreatment of zirconia RBFDP with nanostructured alumina coating after milling of RBFDP's framework<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Survival rate of zirconia RBFDPs | Survival rate is defined by debonding or restoration loss | From baseline through study completion, an average of 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Porcelain chipping | Porcelain chipping | From baseline through study completion, an average of 1 year | 
| Zirconia framework fracture | Zirconia framework fracture | From baseline through study completion, an average of 1 year | 
| Gingivitis | Visual and tactile inspection of gingiva | From baseline through study completion, an average of 1 year | 
| Parodontitis | Gingival sulcus depth measurement | From baseline through study completion, an average of 1 year | 
| Marginal leakage | Discoloration of a restoration margin | From baseline through study completion, an average of 1 year | 
| Secondary caries | Caries between the tooth and restoration margin | From baseline through study completion, an average of 1 year | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Airborne particle abrasion, Nanostructured alumina coating, Resin-bonded fixed dental prostheses