Volumetric changes in articulating interpositional spacers for two-stage temporomandibular joint arthroplasty. A pilot study.

Two-stage temporomandibular joint (TMJ) arthroplasty may involve the placement of a spacer until a final prosthesis is placed. In cases where a patient is not immobilized via intermaxillary fixation (IMF), the spacer is considered to be articulating, and the patient can open their mouth and function more normally during this interval. This study was designed to retrospectively assess the volumetric changes of the spacer within the temporomandibular joint following the use of an articulating bone cement spacer in a two-stage reconstruction. Fourteen patients (thirteen females, one male with mean ± SD age of 58.1 ± 13.0 years underwent two-stage TMJ reconstruction with an articulating spacer. The mean duration of the spacer retention was 142.1 ± 58.4 days. The median volume change of the temporomandibular joint spacer was quantified. Longer retention of the spacer was significantly associated with greater volume change (P = 0.011). There was no impact on prosthesis fit or occlusion at the time of surgery, and prosthesis outcomes were good. This study indicates that the duration of retention of the articulating bone cement spacer in the TMJ influences the amount of spacer volumetric changes, although the amount of change does not appear to be clinically significant.