Classification of Malocclusion Flashcards

Malocclusion Classification Terms

• Mesognathic: Characterized by a normal or straight profile where the jaws are aligned.
• Retrognathic: A condition in which the mandible is positioned behind the maxilla, often leading to an underbite.
• Prognathic: Refers to a condition where the mandible protrudes forward relative to the maxilla, resulting in an overbite.

Occlusion Classes

• Class I Occlusion: Normal occlusion where the first molars interdigitate properly, with a slight overbite.
• Class II Occlusion (Division 1): First molars are positioned further back; characterized by protruded maxillary incisors creating an overbite.
• Class II Occlusion (Division 2): Similar molar positioning as Division 1 but with retroclined maxillary incisors and a deep overbite.
• Class III Occlusion: First molars are positioned more towards the front, often described as having an underbite.

Types of Crossbites

• Posterior Crossbite: Occurs when the posterior teeth are positioned buccal or lingual to their normal occlusion.
• Anterior Crossbite: Maxillary anterior teeth are positioned lingually to the mandibular anterior teeth, disrupting normal bite.

Bite Types

• Open Bite: There is no contact between maxillary anterior teeth and mandibular teeth, with no overlap.
• Edge to Edge Occlusion: Maxillary and mandibular anterior teeth meet at their incisal edges, rather than overlapping.
• End to End Occlusion: Cusp tips of maxillary teeth touch the cusp tips of mandibular teeth.

Overbite Measurement

• Normal Overbite: Maxillary incisor edges align within the incisal third of the mandibular incisors.
• Moderate Overbite: Incisor edges are located within the middle third of the mandibular teeth.
• Severe Overbite: Incisal edges extend into the cervical third of the facial surfaces of the mandibular teeth.

Overjet and Underjet

• Overjet: Horizontal distance between the labial surfaces of maxillary incisors and the incisal edges of mandibular incisors, measured using a periodontal probe.
• Underjet: Condition where maxillary incisors are located lingually to the mandibular incisors.

Tooth Positioning Terms

• Infraversion: Tooth is positioned below the established line of occlusion.
• Labioversion/Buccoversion: A tooth that has moved to a position labial or buccal to its normal alignment.
• Linguoversion: A tooth positioned lingual to the normal alignment.
• Supraversion: Elongation of a tooth above the occlusion line.
• Buccoversion: Similar to labio- and linguoversion, but specifically refers to a tooth positioned buccal to its normal location.
• Torsoversion: A tooth that is turned or rotated from its normal position.