Clinical trials

Study Design: A randomized controlled trial with two parallel arms and an allocation ratio of 1:1. Setting: The study will be conducted in the orthodontic department of Riyadh Elm University hospitals in Riyadh City, Saudi Arabia. Participants: Patients undergoing fixed or clear aligner orthodontic treatment referred to REU dental hospital will be randomly allocated to either the clear aligner group or the fixed orthodontic appliance group. Intervention: Prior to orthodontic treatment, all patients will receive phase I periodontal therapy and oral hygiene instructions. Fixed orthodontic appliances will be bonded using metallic brackets with a 0.022-inch slot and 0.014-inch NiTi archwires. Clear aligner patients will receive Invisalign® treatment. Outcomes and Saliva Collection: Salivary samples will be collected using the spitting method at baseline (T0) and follow-up time points according to the study protocol. Salivary flow rate, pH, and buffering capacity will be assessed as described in the proposal. Randomization and Blinding: Randomization will be performed using a random number generator with allocation concealment via opaque envelopes. The investigators involved in outcome assessment and data analysis will be blinded. Ethical Considerations: The study will be submitted to the Institutional Review Board at Riyadh Elm University and conducted in accordance with IRB policies.

This randomized controlled clinical trial will compare three commonly used interproximal enamel reduction (IPR) techniques during clear aligner therapy in adult patients. IPR is a routine orthodontic procedure in which a small amount of enamel is removed between teeth to create space and help achieve the planned alignment. Seventy-five adults (18 years and older) indicated for receiving clear aligner treatment with IPR prescribed in their digital treatment plan will be enrolled at the orthodontic clinics of Riyadh Elm University (Riyadh, Saudi Arabia) and randomized in a 1:1:1 ratio to one of three IPR techniques: manual abrasive strips (manual arm), motor-driven oscillating strips (motor-driven arm), or abrasive discs (abrasive arm). IPR will be performed by the same trained operator according to the assigned technique. The primary outcome is IPR accuracy, defined as the difference between the amount of IPR planned digitally and the amount performed clinically, measured using intraoral scans taken before and immediately after IPR. Secondary outcomes are short-term periodontal outcomes, assessed on IPR teeth only using plaque and gingival bleeding indices at baseline and at a 6-week follow-up visit. The data analyst will be blinded to group allocation

This randomized crossover study will assess how three aligner-cleaning methods affect early supragingival oral microbial ecology and periodontal health in adults using clear aligners. Each participant will complete three (1-month) periods in a randomized sequence with (1-week) washouts between periods: 1. Mechanical toothbrushing with fluoride toothpaste (control), 2. Chlorhexidine (CHX) mouthwash, and 3. an oxygen-based cleanser (BlueM). Primary ecological outcomes focus on early dysbiosis indicators Fusobacterium nucleatum and Prevotella intermedia measured on retrieved aligner inner-surface biofilm and on supragingival plaque at the gingival margin. Secondary outcomes include periodontal indices (plaque index, gingival index, bleeding on probing) at index teeth and the host inflammatory marker MMP-8 in matrix-paired extracts (plaque and aligner). Study visits occur at baseline and at the end of each 1-month period. Supragingival plaque is collected from the upper and lower first molars and central incisors; used aligners are swabbed immediately after removal. Participants are instructed to wear aligners about 22 hours/day, change trays every 10 days, remove aligners for meals and oral hygiene, and drink only water while aligners are in. Laboratory procedures include blinded culture enumeration under coded labels (performed by a single trained operator, FA), confocal laser scanning microscopy, and RNA isolation with species-specific qRT-PCR; microscopy is conducted unblinded after decoding. The study will determine whether chlorhexidine or an oxygen-based cleanser produces more favorable early ecological changes and periodontal outcomes than mechanical brushing alone in clear aligner therapy.

The goal of this clinical trial is to clinically evaluate the performance of BioFlx in comparison to preformed zirconia crowns in the restoration of primary second molars in pediatric patients. The main questions it aims to answer are: Is there a difference between BioFlx crowns (Group A) and one zirconia (Group B) in terms of crown retention (primary outcome)? Is there a difference between BioFlx crowns (Group A) and one zirconia (Group B) in modified gingival index, plaque index, occlusion, surface roughness, stain resistance, wear of opposing tooth, color match, anatomic form, marginal integrity and discoloration, proximal contact, and recurrent caries at the crown margins? Researchers will compare the clinical performance of Bioflx crowns and zirconia crowns to determine if they are similar. Participants: * Participants will be asked to attend two appointments. During the first visit, a BioFlx crown will be placed on the primary lower second molar, and during the second visit, a zirconia crown will be placed on the contralateral primary lower second molar. * Participants will be recalled and evaluated after 3, 6, and 12 months.

This clinical trial goal is to evaluate the difference in masticatory activities in adult patients treated with clear aligners compared to conventional fixed appliances treatment. The aim of this study is to measure the changes of the activity of the anterior temporalis and masseter muscles in different treatment modality. The activity of the muscles will be evaluated and measured using the surface electromyography (sEMG) BioRadio device before and after the beginning of each treatment modality.

The aim is to evaluate clear aligners' cytotoxicity, leaching, and structural properties and compare them with four cleaning tools. The null hypothesis is the cleansers have no impact on the properties tested.