Clinical Research Directory

Long-term Stability of Treatment With the Twin Block Appliance

The objective of this observational study is to investigate the long-term stability of treatment with the Twin block appliance in a patient group previously treated with a Twin block appliance. The main questions it aims to answer are: 1. Does treatment with the Twin block appliance give a lasting treatment result or does the bite relapse over time due to different factors such as short treatment time, compliance or the patient's natural growth pattern? 2. How many patients that had received treatment with Twin block appliance required additional treatment with fixed appliances and for what reason? Researchers will compare the patients present bite at (T2) by using study casts and cephalometric x-rays and compare this data with previous registrations made pre- (T0) and post-treatment (T1). Additional factors, such as how much relapse a patient has on average, will also be investigated.

Bacterial Diversity Study Using 16S rRNA Sequencing of Periodontal Samples From Patients With Orthodontic Retainers

After completion of orthodontic treatment, a retention phase is required to prevent relapse of tooth malposition. Fixed retention in the mandibular anterior region is commonly used. This type of retainer is bonded to the lingual surfaces of the canines and incisors and may hinder oral hygiene, thereby promoting bacterial plaque accumulation and gingival inflammation. Currently, probably due to the increasing use of clear aligner therapy, clear removable Essix-type retainers are becoming more widely used. Since these retainers can be removed by the patient, they may facilitate oral hygiene. However, studies assessing gingival health and the composition of the subgingival microbiota in patients wearing orthodontic retainers remain scarce. Therefore, the aim of this study will be to assess the composition of the gingival sulcus microbiota and gingival health in patients wearing fixed or removable orthodontic retainers. Ten adult patients who have completed orthodontic treatment will be recruited and divided into two groups: 1. Fixed retention group. 2. Removable retention group. Periodontal parameters will be assessed, and bacterial plaque samples will be collected from the gingival sulcus at five time points: T0: Bracket removal and dental scaling appointment. Periodontal parameters will be assessed, and plaque samples will be collected before bracket debonding and dental scaling. T1: Retainer placement appointment, three days after T0. Periodontal parameters will be assessed, and plaque samples will be collected before retainer placement. T2: One month after retainer placement. T3: Three months after retainer placement. T4: Six months after retainer placement.

Cleaning Methods for Clear Aligners

The goal of this clinical trial is to learn which cleaning method best removes bacteria from clear plastic aligners. Clear aligners are removable orthodontic trays worn to straighten teeth. They sit against the teeth for 20 to 22 hours a day. Bacteria build up on their surfaces within days. No agreed-upon way to clean them exists.The main questions it aims to answer are: Which of four common cleaning methods removes the most live bacteria from worn aligners? Which method leaves the least bacteria visible on the aligner surface under a microscope? Researchers will compare four cleaning methods to see which works best: Brushing with water (control) Soaking in chlorhexidine mouthwash Soaking in an effervescent cleaning tablet Using an ultrasonic cleaner together with a cleaning tablet Participants will: Wear one upper and one lower clear aligner for 10 days Clean the upper aligner twice a day for 5 minutes using their assigned method Return the aligner at the end of 10 days for laboratory testing

Microbial Adherence, Surface Roughness, Effectiveness and Impact on Patients Between Conventional and 3D Printed Twin Block Appliances

The Twin Block appliance is a removable orthodontic appliance that is used to help correct a backward positioned lower jaw in growing children. This appliance works by guiding the lower jaw forward to a specific position over a certain period of time. After completing the treatment, patients often experience improvements in their appearance, such as an improved bite, a more balanced facial profile and improved lip posture. The investigators' interest is to compare two types of Twin Block appliances; traditional (conventional) and 3D-printed, by examining several factors, including the amount of bacteria that stick to them, the surface roughness, and the overall effectiveness of each type. Surface roughness refers to the texture of the appliance's surface, which could influence how much bacteria can accumulate. Rougher surfaces may trap more bacteria, potentially leading to oral health issues such as bad breath, tooth decay, and gum problems. The study will also assess the effectiveness of both the conventional and 3D-printed Twin Block appliances, focusing on factors like how well they perform in improving jaw position and achieving the desired treatment outcomes. Additionally, the investigators want to assess how these appliances affect the quality of life related to oral health. Participants will answer questions about their experience to help understand how the type of appliance impacts their daily lives, comfort, and overall well-being during the course of treatment.