Apparatus (20) for determining surface topology of a teeth portion (26), comprising: a scanning element (90) with a sensing surface a lighting unit (28, 32, 34, 38) to provide a set of rays of incident light transmitted to the part of the teeth (26) along an optical path through said scanning element (90) for generate illuminated spots on said portion of the teeth focusing optics light (42, 44) defining one or more focal planes in front of said detection surface in a variable position by said optics, each light beam presenting its focus on one said one or more focal planes a displacement mechanism (70, 72) coupled to said focusing optics to move said focal plane to the part of the teeth (26) along an axis (Z) defined by the propagation of light rays incident ( 48) a detector (60) having a set of sensing elements (68) for measuring the intensity of each of a plurality of light beams returning from said spots propagating through an opposite optical path of the light rays incident a processor (24) connected to said detector (60) for determining for each light beam, a specific position of the point, the position of the respective plane focal said one or more focal planes which gives the measured maximum beam returned light and, based on the specific positions certain point, generating data representative of the topology of that part of the teeth (26), wherein the scanning element (90), the lighting unit (28, 32 , 34, 38), focusing optics (42, 44) and the displacement mechanism (70, 72) are included together in a portable device, wherein said incident light rays are polarized, the apparatus comprising a filter polarization (62) for filtering, from said beams returned light, light components having the polarization of the incident light rays, so that the light that is detected is having an opposite polarization to the light incident.Aparato (20) para determinar la topología de la superficie de una parte de los dientes (26), que comprende: un elemento de exploración (90) c
