Evidence for the superiority of patient-specific implants (PSI) over stock implants
in temporomandibular joint (TMJ) replacement remains inconclusive. The objective of
this study was to provide guidance for clinical decisions by evaluating whether PSI
offer advantages over stock systems in rehabilitation of the TMJ. A systematic search
was performed in three databases to identify studies reporting mouth opening, pain,
and diet outcomes for PSI and/or stock TMJ implants. Two-arm studies were analysed
separately from pooled single- and two-arm studies; studies with comparable follow-up
times were compared. Forty-two observational studies involving 2221 patients were
included. PSI showed a consistent trend towards greater mouth opening across most
follow-up times; however, a significant difference in favour of PSI was only observed
in two-arm studies at >12 months (mean difference 5.83 mm; P = 0.025). Pain outcomes
were mixed: stock implants favored early pain and late diet change, while PSI favored
pain relief at 6-24 months. The findings suggest PSI should be considered for movement
restrictions, while stock implants may provide an alternative for pain and dietary
needs. Due to the observational nature of the included studies and differences in
study populations across arms, the findings should be interpreted with caution.
