A dosage cap assembly is provided for use with an applicator assembly, the dosage cap assembly including a tip including an outer surface, an attachment end, a second end, and an inner surface defining a tip cavity, wherein the attachment end of the tip includes an engagement mechanism. In this process, an arbitrary point is set in the object region of interest, and a presence area, which is likely to contain the entire object region of interest, is determined in the image using the set arbitrary point and a possible size of the object region of interest. The device can be configured to allow six degrees of motion when comparing one endplate relative to the other.