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Head & Neck Anatomy
Chapter 20 Occlusion
What is occlusion? | The contact relationship between the maxillary and mandibular teeth when the jaw is in a closed position. |
What is centric occlusion? | voluntary position of the dentition that allows the maximum contact when the teeth occlude. |
What happens if a tooth is missing for a long period of time? | Mesial Drifting or supereruption |
Overjet | How many mm the maxillary arch naturally overhangs the mandibular, facially. |
What is the purpose of overjet? | Allows for the extensions of movement in the mandible and keeps soft tissue out of the way during mastication. |
What is overbite? | in centric occlusion, max. incisors overlap the mandibular incisors. |
What is the purpose of overbite? | Allows for contact between posterior teeth during mastication. |
What teeth are anchor support for the dental arches? | Canines & 1st Molars |
Phase I of arch form? | Molars |
Phase II of arch form? | Anteriors |
Phase III arch form? | Premolars |
Phase IV arch form? | Canines then 2nd molars |
Phase V arch form? | Wisdom Teeth |
What is the Curve of Spee? | Anterior to posterior |
What is the Curve of Wilson? | Side to side. |
What is the root axis line? | Each tooth is bisected by its root axis line, showing the angulations of the root. |
What are centric stops? | maximum interdigitation with locking of the two arch positions. |
Centric stops include? | Height of cusp contour, marginal ridges, central fossae, supporting cusps. |
What are supporting cusps? | Lingual cusps of max. post & buccal cusps of mand. post./ Incisal edges of mand. anterior |
What is centric relation? | End point of closure of the mandible: the mand. is in the most retruded position to which it can be carried by the musculature and ligaments. |
What percentage of youth show some degree of malocclusion? | 80% |
What is occlusion? | The contact relationship between the maxillary and mandibular teeth when the jaw is in a closed position. |
What is centric occlusion? | voluntary position of the dentition that allows the maximum contact when the teeth occlude. |
What happens if a tooth is missing for a long period of time? | Mesial Drifting or supereruption |
Overjet | How many mm the maxillary arch naturally overhangs the mandibular, facially. |
What is the purpose of overjet? | Allows for the extensions of movement in the mandible and keeps soft tissue out of the way during mastication. |
What is overbite? | in centric occlusion, max. incisors overlap the mandibular incisors. |
What is the purpose of overbite? | Allows for contact between posterior teeth during mastication. |
What teeth are anchor support for the dental arches? | Canines & 1st Molars |
Phase I of arch form? | Molars |
Phase II of arch form? | Anteriors |
Phase III arch form? | Premolars |
Phase IV arch form? | Canines then 2nd molars |
Phase V arch form? | Wisdom Teeth |
What is the Curve of Spee? | Anterior to posterior |
What is the Curve of Wilson? | Side to side. |
What is the root axis line? | Each tooth is bisected by its root axis line, showing the angulations of the root. |
What are centric stops? | maximum interdigitation with locking of the two arch positions. |
Centric stops include? | Height of cusp contour, marginal ridges, central fossae, supporting cusps. |
What are supporting cusps? | Lingual cusps of max. post & buccal cusps of mand. post./ Incisal edges of mand. anterior |
What is centric relation? | End point of closure of the mandible: the mand. is in the most retruded position to which it can be carried by the musculature and ligaments. |
What percentage of youth show some degree of malocclusion? | 80% |
What is class I malocclusion? | Ideal mesiodistal relationship/ MB of max. first molar occludes with the MB groove the mandibular first molar. |
What is the facial profile of a class I Malocclusion? | Mesognathic. |
What is an open bite? | The anterior teeth do not occlude. |
What is an end to end bite? | The teeth occlude without the maxillary teeth overlapping the mandibular teeth. |
What is cross bite? | When a mand. tooth or teeth are placed facially to the maxillary teeth. |
What is class II malocclusion? | The MB cusp of the max. first molar occlude (more than the width of a premolar) mesial to the MB groove of the mand. first molar. |
What is class II, division I occlusion? | The max. anterior protrude facially from the mand. anterior. |
What is a clinical consideration of class II, division I occlusion? | Mand. incisors super erupt. |
What is the facial profile of a class II, division I occlusion? | Retrognathi- overbite |
What is the palate shape of a class II, division I occlusion? | Narrow and V shaped |
What is class II malocclusion, division II occlusion? | The max. central incisors are upright or retruded. |
What is the facial profile of a class II, division II? | Mesognathic with a prominent chin. |
What is class III malocclusion? | MB cusp of the max first molar occludes distal to the MB groove of the mand. first molar. |
What is the facial profile of a class III mandible? | Prognathic- underbite |
What is clenching? | Teeth are in centric occlusion for long period of time. |
What is bruxism? | Grinding of the teeth. Forceful meshing of teeth that may cause audible noises. |
What is attrition? | Tooth tissues are worn away. |
What is abfraction? | Tooth tissue loss caused by tensile and compressive forces. |