Evaluation of Three Hard Relining Materials in Complete Dentures

Study Overview
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Brief Summary
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Purpose: The purpose of this study is to evaluate three hard relining materials after 3 and 6 months of use with mandibular complete dentures. The effect of hard relining materials on supporting tissues and patients' satisfaction will also be assessed. Materials and Methods: 36 complete edentulous patients who already have maxillary dentures and complaining of instable mandibular dentures will be invited to participate in this study. Mandibular dentures will be relined randomly by one of three relining materials: two chairside relining materials (Tokuyama Rebase II Fast, Tokuyama Dental Co, Japan), and (Flexacryl Hard, Lang Co, USA) and one heat cured acrylic resin (Vertex, Dental technology Co, Holland). The color stability of relining material, peeling, and the effect on supporting tissue will be assessed by two separate prosthodontists after 3 and 6 months of follow up. In addition, patients will be asked to grade there overall satisfaction on a Visual Analogue Scale (VAS) ranging from 0 to 100.

Detailed Description
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Relining denture is a process of resurfacing the tissue side of a denture to make it fit more accurately Direct relining of removable dentures with hard chair-side reline materials is suitable for improving the fit of the denture bases to the supporting tissues. Chairside reline materials are more convenient than those processed in a laboratory because the direct method is faster and does not cause clinically significant dimensional changes of the reline resin. However, when autopolymerized reline resins are used with a direct method, several problems can occur as burning sensation caused by monomers, an exothermic heat reaction and an unpleasant odor. There are three types of hard relining chair-side materials: Dual-polymerized Visible light-polymerized as Triad DuaLine, Light Liner (Hard), Astron LC (Hard).Visible light-polymerized as Lightdon-U, Triad Hi-Flow Reline Material, Triad VLC Reline Material. Finally, autopolymerized as New Truline, Tokuyama Rebase II (Fast) , GC Reline. Other concerns related to direct reline materials include patient tolerance (taste, temperature, odor), color stability, durability and ease of handling and polishing. Few studies evaluated the effect of disinfection solutions on relining materials properties as roughness and hardness. In one study, disinfectant solutions caused a decrease in hardness, whereas with roughness, the materials tested showed a statistically significant increase, except for Tokuyama. Depending on the examined relining materials, some materials have increased and the others have decreased surface roughness after immersion in disinfecting solutions or microwave disinfection. All previous laboratory studies concentrated on the effects of disinfection on relining materials properties as roughness, hardness, color change. However, the clinical studies did not compare chemically cured and heat cured relining materials and their effects on supporting tissue. The aim of this study is to evaluate the clinical performance of two -chemically cured- and heat cured denture relining material after 3 and 6 months of use. In addition, the effect of hard relining materials on supporting tissues, and patients' satisfaction has not been evaluated yet.

Official Title
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Evaluation of Three Hard Relining Materials in Complete Dentures: An In-vivo Study

Conditions
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Complete Mandibular Dentures With Poor Retention

Intervention / Treatment
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* Other: Rebase II Fast
* Other: Flexacryl
* Other: Vertex


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age between 45-80 year, complete maxillary and lower dentures Mandibular dentures with poor retention Exclusion Criteria: Patients with good stability of mandibular dentures. Partial maxillary edentulous patients

Ages Eligible for Study
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Minimum Age: 47 Years
Maximum Age: 78 Years

Sexes Eligible for Study
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Male

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: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Rebase II Fast<br>The direct chair-side relining materiel 'Rebase II Fast' will be used. | Other: Rebase II Fast<br>* It is going to be used a direct relining material<br>|
| Experimental: Flexacryl<br>The direct chair-side relining material Flexacryl will be used | Other: Flexacryl<br>* This is going to be used as a second direct relining material<br>|
| Experimental: Vertex<br>Vertex is a heat-cured resin material which is going to be used for indirect relining | Other: Vertex<br>* This is going to be used as an indirect relining material<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Supporting Alveolar Mucosa Status_3 | According to a clinical examination by two prosthodontists, the supporting alveolar mucosa will be given one of the following levels: Class I: The presence of reddish soft tissues extending to more than half of the area of the supporting mucosa or the presence of large areas of movable tissues. Class II: The presence of irritated soft tissues extending to about third of the area of the supporting mucose or the presence of some areas of movable tissues at the top of the alveolar ridge. Class III: The soft tissues appear in general as normal and fixed except for small isolated areas. Class IV: The soft tissues appear normal and fixed without any signs of irritation or denture-induced injuries. | This will be measured at three months following relining | 
| Supporting Alveolar Mucosa Status_6 | According to a clinical examination by two prosthodontists, the supporting alveolar mucosa will be given one of the following levels: Class I: The presence of reddish soft tissues extending to more than half of the area of the supporting mucosa or the presence of large areas of movable tissues. Class II: The presence of irritated soft tissues extending to about third of the area of the supporting mucose or the presence of some areas of movable tissues at the top of the alveolar ridge. Class III: The soft tissues appear in general as normal and fixed except for small isolated areas. Class IV: The soft tissues appear normal and fixed without any signs of irritation or denture-induced injuries. | This variable will be assessed at six months following relining | 
| Color Stability_3 | The color stability variable has four degrees on clinical examination: no change simple medium large | This will be assessed at three moths following relining | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Color Stability_6 | The color stability variable has four degrees on clinical examination: no change simple medium large | This be assessed at six months following relining | 
| Peeling_3 | This variable is going to be inspected clinically and it has two categories: peeling more than 4 mm peeling less than 4 mm | This variable is going to be assessed at three months following relining | 
| Peeling_6 | This variable is going to be inspected clinically and it has two categories: peeling more than 4 mm peeling less than 4 mm | This variable is going to be assessed at six months following relining | 
| Satisfaction_3 | Patient's satisfaction: patients will be asked to grade there overall satisfaction on a visual analogue scale (VAS) ranging from 0 to 100. | This is going to be measured at three months following relining | 
| Satisfaction_6 | Patient's satisfaction: patients will be asked to grade there overall satisfaction on a visual analogue scale (VAS) ranging from 0 to 100. | This is going to be measured at six months following relining | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Chair-side hard relining, complete denture, patients' satisfaction, supporting tissues, autopolymerized reline resins, heat cured relining material