Purpose: To compare the maximum occlusal force (MOF) in endodontically treated teeth (ETT) and their vital contralateral counterparts and to evaluate the intraoral factors affecting them. Materials and Methods: A total of 30 adult participants presenting with an endodontically treated tooth and its vital contralateral counterpart were recruited for this split-mouth study. MOFs were measured using a wireless sensor network occlusal force recorder, and the mean MOF of ETT was compared to that of their vital contralateral counterparts. Multiple-factor ANOVA was used to examine the association between various clinical factors and MOF. Results: The mean MOF for ETT was significantly higher than their vital counterparts (215.44 ± 74.11 N and 202.40 ± 70.67 N, respectively; P < .001). Among the clinical factors, the MOFs were significantly influenced by the location of teeth (P < .01) and the crown-root ratio (P = .01). Upon further analysis of ETT and control teeth, the location of teeth was identified as the sole factor associated with MOF, with P < .05. Conclusions: The MOFs for ETT were statistically significantly higher than those of their corresponding vital contralateral teeth.