To establish a ratio of variable bone height (Infrazygomatic alveolar crest height) to constant bone height (Infraorbital zygomatic height) and, to estimate the relative sinus floor position from alveolar crest of maxillary first molar region of dentulous Indian males and females, using Digital panoramic radiographs. Panoramic radiographs of 74 patients were included in the study (37 male, 37 female) to measure maxillary posterior vertical bone height and their ratio in dentulous patients. Measurements were made from reference lines drawn from anatomic landmarks on soft digital versions of standardized panoramic radiographs using Kodak dental imaging software. Later the data were analyzed using normal test (Z-score). When the posterior maxillary bone height and their ratio were evaluated in Indian population, the vertical bone height (x, y, z) of males was more than the females. Ratio of Infrazygomatic-alveolar crest distance (y)/Infraorbital-zygomatic distance (x)-was 0.74 for Indian males and females. The relative sinus floor for Indian males was found to be 8.1 mm and that of Indian females to be 7.8 mm. The results are of significant value as “baseline” data, in serial studies where alveolar bone height for a single patient is compared at different times before and after tooth loss. The relative sinus floor position from alveolar crest can help in implant length selection. This study can be used as a diagnostic and predictive tool in implant treatment planning but further long-term evaluation is still required to prove the efficacy of this study.