Improvement of Temporomandibular Joint Lavage in Computational Fluid Dynamics Models with Modified Strategies

Objectives: Arthroscopic lavage is the current minimally invasive techniques used in temporomandibular joint disc displacement (TMJ-DD) for pain reduction and functional improvement. In the current study, we aimed to explore the optimized strategy for different cases together with analyzing the biomechanics and diverse clinical outcomes of 32 approaches with computational fluid dynamics.
Methods: Data was retrospectively analyzed from 312 cases that had undergone arthroscopic lavage for TMJ-DD from 2002 to 2014. Thirty-two types of finite volume models, featuring irrigation needles of 0.8mm or 2.4mm inner-diameters with four combinations of insertion location and direction and with 27.57Kpa or 42.9Kpa lavage pressure, were constructed based on computed tomography images. We investigated the flow pattern, pressure distribution and lavage efficiency of lavage fluid secondary to caliber-varying needles.
Results: Our results demonstrated that the size of lavage needles was the critical factor in determining irrigated flow rate and intra-articular pressure. While the needle location and lavage direction and pressure mainly influence the lavage efficiency. These were consistent with clinical data suggesting that increasing the mouth opening and maximal contra-lateral movement led to better outcomes following lavage with larger needles and smaller lavage pressure.
Conclusions: The findings of this study could be useful for making an individualized lavage plan for TMJ-DD patients according to their main complaint and clinical examinations. Further animal models validation are needed before applying these theories into clinical use.