A Randomised Crossover Clinical Trial to Compare the Effects of Different Storage Conditions on Removable Retainers
Trial Snapshot
- Phase
- Not Applicable
- Status
- Recruiting
- Sponsor
- University of Malaya
- Enrollment
- 24
- Locations
- 1
- Primary Endpoint
- Microbial colony counts of removable retainers in wet and dry storage conditions
Study Overview
Brief Summary
Orthodontic removable retainers are appliances that hold the position of the upper and lower teeth after fixed braces treatment and they can be removed from a patient's mouth. Basically, there are 2 types of removable retainers; Hawley retainer and vacuum-formed retainer.
Hawley retainer is made of an acrylic resin plate that covers the palate for the upper jaw and the back of the arch facing the tongue for the lower jaw. It has thin stainless-steel wires incorporated to fit the first molars and the six front teeth as retention.
Vacuum-formed retainer (VFR) is a clear or transparent plastic retainer. It covers the teeth completely and a small part of the gum.
The investigators' interest is to determine whether the storage conditions will affect the amount of bacteria, appearance and strength of removable retainers. Primarily, the amount of bacteria that sticks to the retainers may cause overall dental and oral health effects such as mouth odour, dental caries and gum problems. The investigators would also like to assess the oral health-related quality of life (OHRQoL) of participants after storing retainers in different storage conditions by answering a questionnaire.
Detailed Description
RATIONALE OF THE STUDY
A non-bias clinical study is required to facilitate the best recommendation to care for the orthodontic retainers. This may prevent the risk of further harms to the oral condition and increase the longevity of the retainers. In turn, this would improve the OHRQoL of orthodontic patients and potentially save the cost of retainer replacements. Therefore, the findings may help to provide evidence-based guidelines for the storage method of removable retainers.
Primary Objective
- To compare the microbial colony counts of removable retainers in wet and dry storage conditions.
Secondary Objectives 2. To compare the surface roughness of removable retainer materials in wet and dry storage conditions. 3. To compare the colour stability of removable retainer materials in wet and dry storage conditions. 4. To compare the compressive strength of removable retainer materials in wet and dry storage conditions. 5. To evaluate OHRQoL of participants storing their removable retainers in dry and wet conditions.
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Crossover
- Primary Purpose
- Screening
- Masking
- Single (Investigator)
Masking Description
Investigator will be masked with the randomization sequance & allocation.
Eligibility Criteria
- Ages
- 18 Years to — (Adult, Older Adult)
- Sex
- All
- Accepts Healthy Volunteers
- Yes
Inclusion Criteria
- •Patients aged 18 years and above
- •Fixed appliance treatment on both the upper and lower arches
- •Ready for debond
- •Planned for either Hawley retainers or VFRs for retention
- •Fit and healthy patients without systemic disease
- •Non-smoking patients
Exclusion Criteria
- •Sectional fixed appliance treatment or fixed appliance treatment on single arch only
- •Planned for double retention with bonded retainers
- •Systemic disease that may affect salivary flow
- •Smoking patients
Arms & Interventions
Hawley retainers in dry storage condition
Acrylic retainers to be stored in a dry retainer box the entire time when not in use.
Intervention: Hawley retainers in dry storage condition (Device)
Hawley retainers in wet storage condition
Acrylic retainers to be stored in a glass of clean tap water the entire time when not in use.
Intervention: Hawley retainers in wet storage condition (Device)
Vacuum-formed retainers in dry storage condition
Thermoplastic retainers to be stored in a dry retainer box the entire time when not in use.
Intervention: VFRs in dry storage condition (Device)
Vacuum-formed retainers in wet storage condition
Thermoplastic retainers to be stored in a glass of clean tap water the entire time when not in use.
Intervention: VFRs in wet storage condition (Device)
Baseline characteristics
Newly constructed Hawley retainers and VFRs will be labeled as baseline samples.
Intervention: Baseline characteristics (Device)
Outcomes
Primary Outcomes
Microbial colony counts of removable retainers in wet and dry storage conditions
Time Frame: 6 months
Removable retainers will be sonicated and vortexed to dislodge bacteria. Serial dilution will be done and bacterial suspension will be pipetted on a BHI agar petri dish. Total bacterial count in CFU/ml will be counted at baseline, T1 and T2.
Secondary Outcomes
- Surface roughness of removable retainers in wet and dry storage conditions(6 months)
- OHRQoL of participants storing their removable retainers in dry and wet conditions(6 months)
- Colour stability of removable retainers in wet and dry storage conditions(6 months)
- Compressive strength of removable retainers in wet and dry storage conditions(6 months)
Investigators
Dr Wan Nurazreena Wan Hassan
Associate Professor, Department of Paediatric Dentistry & Orthodontics, Faculty of Dentistry
University of Malaya