A tomography convergence-type oral scanner comprising: an oral scanning unit comprising a projector including a first light source for generating visible light, and a camera for generating image data by receiving the visible light reflected from a tooth after the visible light generated from the light source is incident on the tooth; an optical tomography scanning unit comprising an OCT body including a second light source that has a different wavelength from the first light source and generates a measurement light incident on the tooth, a beam splitter for splitting the measurement light into a reference light and a measurement light, a reference mirror that reflects the reference light, and a photodetector for detecting an interference light generated by superposition of a signal light generated by reflection of the measurement light by the tooth and the reference light reflected by the reference mirror, and an OCT scan probe including a collimator for converting the measurement light divided by the beam splitter into a parallel light and a MEMS mirror for reflecting the converted parallel light; and a dichroic mirror for transmitting the visible light generated by the oral scanning unit and reflecting the parallel light reflected by the MEMS mirror of the optical tomography scanning unit, thereby irradiating a tooth to be measured, wherein the second light source is near-infrared light of 750 to 1500 nm, the dichroic mirror transmits the first light source that generates visible light and reflects the second light source having a wavelength different from that of the first light source, thereby superimposing optical paths of the light sources of different regions, the oral scanning unit obtains image data of an external surface shape of the tooth, and the optical tomography scanning unit obtains internal tomography image data of the tooth, characterized in that a depth of focus of the optical tomography scanning unit is checked based on a depth information that obtained from the image data of the external surface shape obtained by the oral scanning unit, and only when a depth of the optical tomography scanning unit is the depth of focus based on the depth information obtained by the oral scanning unit, the internal tomography image data of the tooth obtained by the optical tomography scanning unit is registered. an oral scanning unit comprising a projector including a first light source for generating visible light, and a camera for generating image data by receiving the visible light reflected from a tooth after the visible light generated from the light source is incident on the tooth; an optical tomography scanning unit comprising an OCT body including a second light source that has a different wavelength from the first light source and generates a measurement light incident on the tooth, a beam splitter for splitting the measurement light into a reference light and a measurement light, a reference mirror that reflects the reference light, and a photodetector for detecting an interference light generated by superposition of a signal light generated by reflection of the measurement light by the tooth and the reference light reflected by the reference mirror, and an OCT scan probe including a collimator for converting the measurement light divided by the beam splitter into a parallel light and a MEMS mirror for reflecting the converted parallel light; and a dichroic mirror for transmitting the visible light generated by the oral scanning unit and reflecting the parallel light reflected by the MEMS mirror of the optical tomography scanning unit, thereby irradiating a tooth to be measured, wherein the second light source is near-infrared light of 750 to 1500 nm, the dichroic mirror transmits the first light source that generates visible light and reflects the second light source having a wavelength different from that of the first light source, thereby superimposing optical paths of the light sources of different regions, the oral scanning unit obtains image data of an external surface shape of the tooth, and the optical tomography scanning unit obtains internal tomography image data of the tooth, characterized in that a depth of focus of the optical tomography scanning unit is checked based on a depth information that obtained from the image data of the external surface shape obtained by the oral scanning unit, and only when a depth of the optical tomography scanning unit is the depth of focus based on the depth information obtained by the oral scanning unit, the internal tomography image data of the tooth obtained by the optical tomography scanning unit is registered.