It is determined by analyzing dentofacial esthetics, tooth proportion, phonetics and the kinetics of the lower lip. The maxillary incisal edge position is considered the starting point of any maxillary reconstruction. The LTR classification is based on the relationship between the optimal dimensions and position of the maxillary central incisor, the maxillary lip (dimensions and dynamics) and the architecture of the edentulous ridge. Think of it as a guidepost for treatment planning the edentulous maxilla (either for fixed or removable prostheses) that helps clinicians identify the final prosthetic design while providing a case-specific risk assessment guide. This is why the LTR (Lip-Tooth-Ridge) classification was developed: to make navigating this rehabilitation planning smoother, swifter and, at the end of the day, more successful. The complexity is mainly due to anatomical characteristics, bone resorption pattern, quality of bone, development of prosthetic emergence profile, oral hygiene limitations, influence of the teeth and hard tissue during speech and the important role the prosthesis plays in overall facial and dental esthetics. The prosthetic rehabilitation of the edentulous maxilla is known to be a challenge and requires meticulous planning.
