This study is about a treatment for a jaw condition called temporomandibular joint (TMJ) subluxation. In this condition, the jaw can move too far forward during mouth opening, which may cause repeated jaw locking and problems with normal function.

The treatment being studied is platelet-rich plasma (PRP) injections. PRP is made from a person's own blood and may help improve joint stability and reduce symptoms.

In this study, 40 adults with TMJ subluxation were randomly assigned to receive PRP with either a lower or higher platelet concentration. Each participant received 2 injections, given 2 weeks apart.

The study measured jaw pain, how often locking happened, mouth opening, and joint clicking before treatment, after 6 months, and after 5 years.

The goal of this study is to find out whether the amount of platelets in PRP changes how well this treatment works.

This prospective, double-blinded, parallel-group randomized clinical trial was conducted to evaluate whether platelet concentration influences the clinical efficacy of platelet-rich plasma (PRP) prolotherapy in the management of temporomandibular joint (TMJ) subluxation. TMJ subluxation is characterized by recurrent episodes of excessive anterior translation of the mandibular condyle beyond the articular eminence, often resulting in transient jaw locking and functional impairment.

A total of 40 adult patients (≥18 years) diagnosed with TMJ subluxation according to the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD), supported by imaging evidence, were enrolled and randomly allocated in a 1:1 ratio into two groups: low-concentration PRP (L-PRP) and high-concentration PRP (H-PRP). PRP was prepared using standardized centrifugation protocols (1,500 rpm for L-PRP and 3,200 rpm for H-PRP). All participants received two intra-articular and pericapsular injections separated by a 2-week interval.

The primary outcomes were TMJ pain on function, assessed using a visual analog scale (VAS), and frequency of joint locking (episodes/day). Secondary outcomes included maximal mouth opening (MMO, mm) and presence of joint clicking. Outcomes were assessed at baseline, 6 months, and 5 years following treatment.

The study aimed to determine whether variations in platelet concentration affect clinical outcomes of PRP prolotherapy and to provide evidence for optimizing PRP preparation protocols in the management of TMJ subluxation.

Inclusion Criteria: patients aged ≥ 18 years -

Exclusion Criteria: patients aged < 18 years

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Individual participant data (IPD) will not be shared due to institutional regulations and ethical considerations regarding patient confidentiality and data protection.

Participants and outcome assessors were blinded to group allocation. The clinician performing the intervention was not blinded due to the nature of the procedure.