This is achieved when the eyes are horizontally fixed.In this position, the occlusal plane is horizontal, which is also the case of the auricular-nasal plane, which passes through the upper border of the external auditory conduct and the anterior nasal spine.
En esta posición, el plano oclusal es horizontal, así como el plano auriculonasal, que pasa por el borde superior del conducto auditivo externo y por la espina nasal anterior.