Background: Prosthodontic treatment planning in edentulous patients requires precise determination of occlusal dimensions, particularly in the mandibular arch where distinct landmarks are lacking. This study aimed to investigate the average distance between the lingual frenum and mandibular incisal edges in Jordanian patients to aid in pre-extraction records. Methods: A total of 126 patients aged between 40 and 60 years with lower partially edentulous ridges and poorly diagnosed lower anterior teeth attended the prosthodontic clinic at Princess Haya Bint Al-Hussein Military Hospital "in Ajloun First, a lower alginate impression was taken in the clinic and then it was poured into a dental cast. Subsequently, the distance between the lingual frenum and the mandibular incisal margins was measured on the dental cast using a standardized vernier caliper. Descriptive statistics and the Shapiro-Wilk test were employed for data analysis. Results: The results showed a standard deviation of 1.58 millimeters; the mean distance was 9.39 millimeters between the mandibular incisal edges and the lingual frenum. Despite the non-normal distribution of the data (p < 0.001), the central tendency measurements provide reliable estimates. The range of distances varied from 6 to 14 millimeters. Conclusion: This study offers valuable insights into the distance between the lingual frenum and mandibular incisal edges in Jordanian patients, aiding in prosthodontic treatment planning. Despite data non-normality, the findings provide a reference point for determining occlusal rim height and incisor setting. Further research is warranted to explore additional factors influencing mandibular prosthetic rehabilitation outcomes.