An interventional study of Fixed orthodontic appliances and Clear Aligner Treatment in Orthodontic Treatment and Saliva, sponsored by Riyadh Elm University. Not yet recruiting at 1 site in Saudi Arabia. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-09-09.
Sponsored by Riyadh Elm University · Not applicable, Interventional, and Other
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 study is a randomized controlled clinical trial designed to evaluate changes in salivary parameters in patients undergoing fixed orthodontic treatment or clear aligner therapy. Patients referred to the orthodontic department of Riyadh Elm University dental hospital will be screened for eligibility and randomly allocated into two parallel groups with an allocation ratio of 1:1.
Prior to the initiation of orthodontic treatment, all participants will undergo phase I periodontal therapy and receive standardized oral hygiene instructions. Patients in the fixed orthodontic appliance group will be treated using metallic brackets with a 0.022-inch slot and initial 0.014-inch nickel-titanium archwires. Patients in the clear aligner group will receive clear aligner treatment according to the prescribed protocol.
Salivary samples will be collected using the spitting method at baseline before the start of orthodontic treatment (T0) and at subsequent follow-up time points as specified in the study protocol. Salivary flow rate, salivary pH, and buffering capacity will be assessed at each time point using standardized methods described in the proposal.
Randomization will be carried out using a random number generator, with allocation concealment ensured through the use of opaque sealed envelopes. The investigators involved in outcome assessment and data analysis will be blinded to group allocation.
This study will be conducted following approval from the Institutional Review Board (IRB) of Riyadh Elm University and in accordance with institutional ethical guidelines.
Riyadh Elm University is the lead sponsor of 26 studies on the registry; 10 are open to participants now.
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Exclusion Criteria:
Study subjects in control group will receive fixed orthodontic appliances with metallic brackets of 0.022-inch slot size (American Orthodontics). The bonding process will be performed using the same adhesive (BracePaste, American Orthodontics) for all patients, and treatment will be initiated with 0.014-inch NiTi archwires (Highland Metals).
Device: Fixed orthodontic appliances
Study subjects in Clear Aligner treatment group will receive Invisalign® (Align Technology, Inc., Tempe, AZ, USA). The Clear Aligner treatment protocol will be followed until the end of the treatment.
Device: Clear Aligner Treatment
Study subjects in control group will receive fixed orthodontic appliances with metallic brackets of 0.022-inch slot size (American Orthodontics).
Study subjects in Clear Aligner treatment group will receive Invisalign® (Align Technology, Inc., Tempe, AZ, USA). The Clear Aligner treatment protocol will be followed until the end of the treatment.
Salivary flow rate
The salivary flow rate will be recorded in each patient. Two mL of whole unstimulated saliva will be collected in a graduated tube. The salivary flow rate will be recorded in all the four time points T0, T1, T3 and T4.
Time frame: The outcome measure will be assessed at (T0) just before the commencement of fixed appliance and Clear Aligner therapy, at one week (T1), at two weeks (T2), after three months (T3), and at six months (T4) of treatment.
Salivary pH
The pH values will be assessed using portable pH meter strips at the same four time points. Salivary pH will be measured at T0, T1, T3 and T4.
Time frame: The outcome measure will be assessed at (T0) just before the commencement of fixed appliance and Clear Aligner therapy, at one week (T1), at two weeks (T2), after three months (T3), and at six months (T4) of treatment.
Salivary buffering capacity
Buffer capacity will be determined by quantitative test using a hand-held pH meter method. This method will involve addition of 0.5 ml of saliva to 1.5 ml of 5 mmol/L HCl. Mixtures will be vigorously shaken. Then stream of Nitrogen will be passed through the mixture for 20 min to eliminate carbon dioxide from the sample and allowed to stand for 10 min when the final pH will be measured. The salivary buffering capacity will be measured at T0, T1, T3 and T4.
Time frame: The outcome measure will be assessed at (T0) just before the commencement of fixed appliance and Clear Aligner therapy, at one week (T1), at two weeks (T2), after three months (T3), and at six months (T4) of treatment.
Plan to share: Undecided
Start is estimated for Sep 2026; primary completion for Jun 2027, 9 months later.
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Riyadh Elm University