Objective: The present study is a model analysis which correlates the linear and angular measurements of anterior segment with posterior segment of maxillary arch and study the intra arch discrepancy as a whole. Materials and Methods: Sample was divided into three groups. 51 patients belong to group 1, 70 to group 2, 55 to group 3.The study casts were analyzed for correlating the angular (ALPHAr, THETA) and linear measurement (OCI). Results: All three variables OCI, ALPHAr and THETA can be important discriminant of Class I, Class II and Class III malocclusions.A mathematical MODEL to classifythe samples in the three groups is derived. Conclusion: Arch form can be predicted, whether it is constricted or expanded in anterior or posterior segment using values ALPHAr and THETA. Using the linear value OCI and angular values ALPHAr and THETA, we can classify a given case into Class I, Class II or Class III malocclusion.