Background/Objectives The aim of this study was to develop an evidence-based scoring system for prioritizing limited orthodontic resources based on orthodontic treatment need (OTN), orthodontic treatment complexity (OTC), and orthodontic treatment priority (OTP), which is not merely a scoring system for malocclusion but also a comprehensive classification of orthodontic issues incorporating patient- and treatment-related factors, called Orthodontic Care Index (OCI).Materials and methods The development of the OCI involved eight phases, starting with a systematic literature review to identify all possible parameters involved in determining OTN, OTC, and OTP. An eight-member orthodontic specialist panel then evaluated and scored the significance of each parameter, resulting in a parameter-score list. Subsequently, a retrospective convenience sample of 61 patients was scored with the parameter-score list, and using the same convenience sample a gold standard was established through the expert opinion of a third orthodontic panel. Linear regression analysis was used to estimate weights of importance and construct a formula to calculate index scores. Lastly, the expert opinion was compared to the index scores, to determine the index performance.Results The preliminary index separately calculates OTN, OTC, and OTP for a patient as the weighted sum of his/her domain scores. The sensitivity of the index for predicting OTN, OTC, and OTP was high (98.1%, 82.9%, and 92.7% respectively), while the variability of each was relatively low (52.1%, 31.2%, and 52.6% respectively).Conclusions/Implications The OCI shows promise as a guideline for prioritizing orthodontic care. It will be further refined and validated to enhance its performance and usefulness.