Arthrocentesis is a minimally invasive procedure used to treat internal derangements and inflammatory degenerative disorders of the temporomandibular joint (TMJ) when conservative treatments fail. It involves lavage of the joint space to remove pain-inducing mediators and facilitate lysis of adhesions (Guarda-Nardini et al., 2008; Nagori et al., 2021). This procedure, characterized by its simplicity, cost-effectiveness, and short duration, has proven to be highly effective in reducing pain, improving jaw mobility, and minimizing joint sounds (Grossmann et al., 2017; Nitzan et al., 1991; Şentürk et al., 2016). Since its initial introduction, it has been widely utilized and continuously refined through various modifications to enhance its efficacy (Hasanoğlu Erbaşar et al., 2024; Şentürk et al., 2018a).

Temporomandibular joint arthrocentesis was first introduced in 1991 by Nitzan et al. The traditional technique involves the use of two needles to access the superior joint space, with one serving as the inflow port and the other as the outflow port (Nitzan et al., 1991). This method, classified as "double-puncture arthrocentesis" (DPA), is still widely used today. However, due to the technical challenges associated with the use of two needles, less invasive and more easily applicable single-puncture arthrocentesis (SPA) techniques have been developed (Folle et al., 2018; Şentürk et al., 2018a). SPA techniques are further categorized into Type 1 and Type 2 based on the method of fluid inflow and outflow. In Type 1, fluid inflow and outflow occur through the same lumen, whereas in Type 2, separate ports are used. (Şentürk et al., 2018a).

Among the most commonly used cannulas in Type 2 techniques are the Y-shaped cannula, Shepard cannula, double-needle cannula, and concentric cannula. The Y-shaped cannula, Shepard cannula, and double-needle cannula share a similar basic structure and working principle (Şentürk et al., 2018a; Folle et al., 2018). These designs allow simultaneous fluid inflow and outflow, minimizing the need for cannula repositioning and facilitating efficient fluid flow, which reduces procedure time (Nagori et al., 2021b; Navaneetham et al., 2023). Among these, the Y-shaped cannula stands out as a more practical choice due to its lower cost and easier accessibility. For these reasons, it was included as one of the techniques compared in this study.

Another important SPA Type 2 technique, the concentric needle technique, was first introduced into the literature in 2011 by Öreroğlu et al. (2011). Although this technique has gained attention for its less traumatic nature, cost-effectiveness, lack of requirement for additional sterilization, and ease of application (Şentürk et al., 2018a) concrete data regarding its intraoperative success remain quite limited. To the best of our knowledge, only the studies by Grossman et al. (Grossmann and Poluha, 2024) and Erbaşar et al. (Hasanoğlu Erbaşar et al., 2024) have provided data on the operation time of this technique, while no data evaluating the procedural difficulty have been reported. Moreover, the original technique described and recommended by Öreroğlu et al. (2011), which involves the use of 21-gauge and 27-gauge needles, was not employed in these studies. In the study by Grossman et al. (Grossmann and Poluha, 2024), two needles were used: an 18-gauge and a 21-gauge needle in the first group, and an 18-gauge and a 25-gauge needle in the second group. In the study by Erbaşar et al. (Hasanoğlu Erbaşar et al., 2024), 19-gauge and 21-gauge needles were utilized. Therefore, our study is the first to evaluate the original concentric needle technique described by Öreroğlu et al. (2011) in terms of intraoperative parameters.

This study aims to compare, for the first time in the literature, two significant SPA Type 2 techniques, the concentric needle cannula technique and the Y-shaped cannula technique, in terms of intraoperative parameters, including procedure duration, the number of cannula relocations, and procedural difficulty. Additionally, we aim to address the gap in the literature by providing intraoperative data on the original concentric needle technique.