title: Natural position of the head: review of two-dimensional and three-dimensional methods of recording.
abstract: Both the correct position of the patient's head and a standard system for the acquisition of images are essential for objective evaluation of the facial profile and the skull, and for longitudinal superimposition. The natural position of the head was introduced into orthodontics in the late 1950s, and is used as a postural basis for craniocervical and craniofacial morphological analysis. It can also have a role in the planning of the surgical correction of craniomaxillofacial deformities. The relatively recent transition in orthodontics from 2-dimensional to 3-dimensional imaging, and from analogue to digital technology, has renewed attention in finding a versatile method for the establishment of an accurate and reliable head position during the acquisition of serial records. In this review we discuss definition, clinical applications, and procedures to establish the natural head position and their reproducibility. We also consider methods to reproduce and record the position in two and three planes.
authors.affiliation: Doctoral School in Life and Health Science - PhD Program in Experimental Medicine and Therapy - CIR Dental School - University of Turin, Turin, Italy; Department of Biotechnological, Biomedical and Translational Sciences - Centro Universitario di Odontoiatria - Section of Orthodontics - University of Parma, Parma, Italy; Orthodontics and Gnatology - Masticatory Function - Department of Surgical Sciences - University of Turin, Turin, Italy. Electronic address: diana.cassi@unipr.it.
authors.forename: D
authors.initials: D
authors.lastname: Cassi
authors.affiliation: Doctoral School in Life and Health Science - PhD Program in Experimental Medicine and Therapy - CIR Dental School - University of Turin, Turin, Italy; Orthodontics and Gnatology - Masticatory Function - Department of Surgical Sciences - University of Turin, Turin, Italy.
authors.forename: C
authors.initials: C
authors.lastname: De Biase
authors.affiliation: Orthodontic Division, Dental School, University of Brescia, Brescia, Italy.
authors.forename: I
authors.initials: I
authors.lastname: Tonni
authors.affiliation: Department of Biotechnological, Biomedical and Translational Sciences - Centro Universitario di Odontoiatria - Section of Orthodontics - University of Parma, Parma, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Gandolfini
authors.affiliation: Department of Biotechnological, Biomedical and Translational Sciences - Centro Universitario di Odontoiatria - Section of Orthodontics - University of Parma, Parma, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Di Blasio
authors.affiliation: Doctoral School in Life and Health Science - PhD Program in Experimental Medicine and Therapy - CIR Dental School - University of Turin, Turin, Italy; Orthodontics and Gnatology - Masticatory Function - Department of Surgical Sciences - University of Turin, Turin, Italy.
authors.forename: M G
authors.initials: MG
authors.lastname: Piancino
mesh_terms: D002508:Cephalometry; D006257:Head; D006801:Humans; D021621:Imaging, Three-Dimensional; D009970:Orthodontics; D004856:Postural Balance; D011187:Posture; D015203:Reproducibility of Results; D012886:Skull
keywords: Cephalometry; Head posture; Orthognathic surgery; Three-dimensional imaging