Abstract: A protective sleeve comprises a housing configured to fit over a portion of an intraoral scanning device and protect the intraoral scanning device from an external environment. The intraoral scanning device comprises a first aperture for transmission of optical signals, the housing defines a second aperture for transmission of the optical signals, and the second aperture is aligned with the first aperture when the housing is fit over the portion. The protective housing comprises one or more supports attached to the housing and a transparent element secured by the one or more supports and aligned with the second aperture. The transparent element is further aligned with a defogging element of the intraoral scanning device when the housing is fit over the portion, and an external surface of the transparent element is to receive heat generated by the defogging element to prevent fogging of the transparent element.