Frankfort Horizontal Deviation Comparison in Natural Head Position on Discrepancy of Skeletal Pattern (Cephalometry Study)

Cephalometry remain imperative in diagnosis and treatment planning. Commonly used craniofacial reference plane such as Frankfort Horizontal (FH), have shortcomings, including their variation individual orientation when Natural Head Position (NHP), so FH cannot be considered a true horizontal. The purpose of this study was to determine deviant FH, to highlight effect of deviant FH on the determination cephalometric values in vertical skeletal discrepancy cases dan to construct a true horizontal line (HOR) as alternate reference plane. Lateral cephalometric roentgenograms from 104 randomly selected patients, then determined FH inclination. Control group was created from FH inclination come near to true horizontal and study group was created from FH inclination away from true horizontal. Independent t test was done for both the groups to compare the values obtained and determine the statistic difference. Statistical analysis in control group shows that there is no significant difference between FH and HOR, which prove that HOR could be used as an alternative to FH. The study group showed a significant statistic difference, resulting in erroneous analysis if the deviant DH was used.