In dentistry, mesial describes the tooth surface that faces the middle of the dental arch — the midline between the two central incisors. The opposite term is distal.
Greek mésos = middle
towards the middle of the dental arch
mesial
Mesial and distal are the two most important surface terms used on a tooth in dentistry. They are supplemented by vestibular (towards the cheek or lip), oral (towards the oral cavity) and occlusal (towards the chewing surface).
The difference from general anatomy matters: there, distal simply means further from the trunk. On the dental arch, the term refers instead to the midline between the central incisors.
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