Tooth Morphology 1 Flashcards
What is the palatal region of the mouth?
Surface of the maxillary tooth which faces the palate
What is the lingual region of the mouth?
Surface of the mandibular tooth which faces the tongue
What is the labial region of the mouth?
Surface of the incisors and canines facing the lips
What is the buccal region of the mouth?
Surface of the pre molars and molars facing the cheek
What is mesial in terms of the oral cavity?
Surface of the tooth which faces towards the midline of the dental arch
What is distal in terms of the oral cavity?
Surface of the tooth which faces away from the midline of the dental arch
What is the occlusal surface of a tooth?
The biting surface of a molar or premolar
What is the incisal margin of a tooth?
The cutting edge of an incisor or canine
What is a cusp?
Pronounced elevation on the occlusal surface of a tooth
What is a tubercle?
A small elevation on the crown of a tooth
What is the cervical margin?
Surface above the junction of the crown and root
What is cingulum?
A bulbous convexity near the cervical region of a tooth
What is a ridge?
Any linear elevation on the tooth surface
What is a marginal ridge?
A ridge at the mesial or distal edge of the occlusal surfaces of molar and premolars
What is a fissure?
A long cleft between cusps or ridges
What is a fossa?
A rounded depression on a tooth’s surface
What are contact points?
Distal surface of one tooth abuts firmly to the mesial surface of the adjacent tooth
What maintains contact points?
Mesial drift
What is mesial drift?
The tendency for teeth to move in a mesial direction
What can occur if contact points are lost?
Food can become impacted between teeth
What is the importance of marginal ridges?
Push food into occlusal surfaces
What 3 things cause variation in tooth morphology?
- Age
- Disease
- Developmental anomalies or defects
What 4 tooth morphology variations occur with age?
- Attrition on tooth surface
- Receding gingiva
- Cementum thickness increases
- Teeth become darker in colour
What is an example of a local disease of the oral cavity?
Caries
What is a neonatal line?
Line left on a tooth due to serious disease during tooth development
What are 5 developmental defects of the oral cavity?
- Number of teeth
- Size of teeth
- Fusion of teeth
- Transportation of teeth
- Root morphology
What are 3 ways the number of teeth in the oral cavity can be affected?
- Hypodontia
- Anodontia
- Hyperdontia
What is hypodontia?
When one or more teeth fail to develop
What 3 teeth are most likely to be affected by hypodontia?
- Lateral incisors
- Pre molars
- Molars
What is anodontia?
Rare congenital disorder where all teeth are missing
What is hyperdontia?
Additional teeth are found in the dental arch
Where are extra teeth usually found in the dental arch?
Midline between upper central incisors
What is the main issue with hyperdontia?
Extra teeth may obstruct the eruption pathway of permanent central incisors
What are 2 ways the size of teeth in the oral cavity can be affected?
- Microdontia - Unusually small teeth
2. Macrodontia - Unusually large teeth
What Is a germinated tooth?
When the enamel organ partially divides during tooth development to give 2 crowns on a tooth instead of 1
What is the transposition of teeth?
Positional interchange of 2 adjacent teeth
Where are 2 locations which transportation of teeth most likely occur?
- Permanent maxillary canine transposed with first premolar
2. Permanent mandibular canine transposed with lateral incisor
What are 4 ways root morphology can be variant?
- Unduly curvatures
- Thickened at apex
- Concrescence
- Unusually long roots
What causes a root to thicken at the apex?
Hypercementosis
What is concrescence?
Roots of adjacent teeth become joined by cementum
What are 2 clinical points with regards to long roots?
- Root apices of maxillary teeth could invaginate the maxillary sinus
- Roots of permanent 3rd mandibular molars may be in close relationship with inferior alveolar nerve
