title: A cephalometric study to ascertain the use of nasion as a guide in locating the position of orbitale as an anterior reference point among a population of South Coastal Karnataka.
abstract: BACKGROUND
  To ascertain the use of nasion as a guide in locating the position of orbitale as an anterior reference point in the face-bow transfer records in individuals having different facial types.
  
  
  OBJECTIVE
  This study evaluated the distance from the nasion to the orbitale using cephalometric measurements to ascertain the use of nasion as a guide in locating the position of orbitale as an anterior reference point in individuals having different facial types among a population of South Coastal Karnataka.
  
  
  METHODS
  Anthropometric measurements were made on 61 subjects and they were classified into mesoprosopic, euryprosopic and leptoprosopic facial type groups based upon the prosopic index. Lateral cephalometric radiographs were taken and nasion to orbitale distance was measured. The collected data was tabulated and statistically analyzed.
  
  
  METHODS
  The statistical test carried out was the analysis of variance test and correlations were checked for using Pearson's correlation test.
  
  
  RESULTS
  The study found the mean distance from nasion to orbitale was 24.25 mm with a standard deviation 4.26 mm. A good correlation was found between prosopic index and nasion to orbitale distance. No statistically significant variation in nasion to orbitale distance in individuals of different facial types was found.
  
  
  CONCLUSIONS
  Although, variation exists it was not statistically significant. However, since a large range of measurements were found, prior evaluation using cephalometric radiographs may be necessary in certain individuals.
authors.affiliation: Department of Prosthodontics, A. B. Shetty Memorial Institute of Dental Sciences, Nitte University, Mangalore, Karnataka, India.
authors.forename: Chethan
authors.initials: C
authors.lastname: Hegde
authors.forename: Nikhil J
authors.initials: NJ
authors.lastname: Lobo
authors.forename: Krishna D
authors.initials: KD
authors.lastname: Prasad
keywords: Anterior reference point; face-bow; facial types; nasion; orbitale; prosopic