Effect of Low-Level Laser Therapy on Osseointegration of Posterior Dental Implants: A Randomized, Double-Blind, Split-Mouth Clinical Trial

Examining the effect of low level laser therapy on osseointegration of posterior implants

Randomized, double-blind, split-mouth clinical trial, on 17 patients (34 implants). Randomization is performed using a computer-generated random number sequence

The study is conducted at the clinic of Mashhad School of Dentistry. Patients requiring bilateral implants in the premolar and molar regions of the mandible are selected. One side is considered as the test group and the opposite side as the control group. Patients and evaluators are blinded to the grouping. Implant stability measurements are performed using the Ostell device in four sessions

Inclusion criteria: - Patients should have sufficient bone volume for implant placement without GBR (Guided Bone Regeneration). - Patients should have signed an informed consent form. - The target bone should be type D3 or D4. - Patient cooperation should be excellent. Exclusion criteria:1. Patients with insufficient bone volume requiring GBR 2. Bone type D1 or D2 3. Need for implants in areas other than mandibular premolars and molars4. Need for implants only on one side of the mandible (inability to perform split-mouth design)5. Systemic diseases affecting bone healing process6. Use of medications affecting bone metabolism7. History of radiotherapy in the head and neck region

Intervention group: Low-level laser therapy (LLLT) with 940 nm wavelength, 100 mW output power, in continuous mode, for 40 seconds from buccal and lingual sides, on days 2, 4, 6, 8, 10, and 12 post-surgery. Control group: Same protocol with the laser device turned off

Implant stability measured by Ostell device on days 0, 10, 21, and 42 post-surgery

This study will use a simple randomization method with a split-mouth design. The randomization process will be as follows: - Randomization unit: Individual patient's mouth sides (right vs left) - Randomization tool: Computer-generated random number sequence - Sequence generation: A statistician not involved in the study will generate a random sequence using statistical software (e.g., R or SAS) - Allocation concealment: Opaque, sealed envelopes will be used. Each envelope will contain the allocation for the right side of the mouth (laser or control), with the left side automatically assigned to the opposite group. - Implementation: After the patient is deemed eligible and has signed the informed consent, the treating clinician will open the envelope to determine which side receives the laser treatment. The split-mouth design ensures that each patient serves as their own control, reducing inter-individual variability.( 1. A statistician outside the research team generates a random list of 0s and 1s, equal to the number of patients, using R software (version 4.1.2). The number 0 indicates laser allocation to the right side, and 1 indicates laser allocation to the left side. 2. This random list is placed in opaque, sealed envelopes. Each envelope is marked with a serial number corresponding to the patient's entry number into the study. 3. After confirming the patient's eligibility and signing the informed consent form, the research assistant (who is not involved in the treatment process) opens the envelope for that patient and informs the surgeon of the allocation. 4. Based on this allocation, the surgeon performs the laser treatment on the specified side. The opposite side is automatically assigned to the control group. 5. Each patient's allocation is recorded on a separate form accessible only to the research assistant and the surgeon. This method ensures that the allocation is completely random and cannot be predicted or manipulated.)

This study is designed as a randomized, double-blind clinical trial: 1. Patients (Participants): Patients are blinded to which side of their mouth is receiving laser treatment and which side is the control group. They do not know in which sessions the laser is active and in which it is turned off. 2. Evaluators: The individuals responsible for measuring implant stability using the Ostell device are blinded to which side has received laser treatment and which is the control group. They simply perform the measurements without knowledge of the implant grouping. The principal investigator and the treatment team applying the laser cannot be blinded as they need to know which side to treat with the active laser and which with the inactive laser. Statistical analysts can also be kept blinded by providing them with coded data without specifying the groups. This type of blinding helps reduce bias in the evaluation of results, as neither patients nor evaluators are aware of the grouping. Additionally, the use of an inactive laser in the control group (instead of not using the device at all) helps maintain patient blinding, as they cannot discern whether they have received actual laser treatment or not. The main researcher and the treatment team applying the laser cannot be blinded, as they need to know which side to treat with the active laser and which with the inactive one. Statistical analysts can also be kept blinded by providing them with coded data without specifying the groups

All data is potentially shareable after de-identification of individuals.

The access period begins immediately after the publication of results.

The data will be available to researchers working in academic and scientific institutions. Those working in industry can also apply to receive the data.

The data and documents from this study are to be used solely for research purposes and in compliance with confidentiality principles. Access to the data is permitted only for the research team, and any publication of results will be without mentioning patients' personal information.

To obtain data or documents related to this study, please contact the principal investigator, Dr. [Negar Asgarian], via email :Asgariann4001@mums.ac.ir . Requests will be addressed after review and approval by the university's research ethics committee.

Submit a written request to the principal investigator Review of the request by the research team Evaluation and approval of the request by the research ethics committee If approved, signing of a confidentiality agreement by the requester Provision of data or documents in coded form without patients' personal information This process typically takes 2 to 4 weeks.