Tooth Morphology Flashcards
Morphology
The study of the form of an organ or body part
Tooth morphology
Study of the size, shape, form and structure of the teeth
How many dental arches do we have?
2
What are the two dental arches
Maxillary and mandibular
Occlusion is when?
The teeth in both arches are in contact
Dentition refers to
The arrangement of the teeth as a set; the natural teeth in the dental arch
Primary dentition
Baby teeth
Permanent dentition
Adult teeth
How many dentition periods?
3
What are the 3 dentition periods?
Primary, mixed, permanent
Primary (deciduous) dentition
Assists with speech, provides chewing surfaces to strengthen muscles of mastication
-important for guiding permanent teeth into proper position
Premature loss of primary teeth can lead to problems in
Alignment, spacing and occlusion of permanent dentition
In primary dentition there is a total of how many teeth and when does it occur ?
20 teeth. Occurs between 6 months and 6 years of age
Mixed dentition
Occurs between 6 and 12 years when primary teeth are exfoliating and permanent teeth are erupting
Succedaneous teeth
Permanent teeth that replace deciduous teeth
How many teeth in the permanent dentition
32
Anterior teeth
Incisors and canines (cuspids)
Posterior teeth
Premolars (bicuspids) and molars
Each arch can be divided into 2 what?
Sextants
Sextants are
1/6th of the dentition
Sextants divided
into maxillary right and left (posterior and anterior)
Mandibular right and left (posterior and anterior)
Quadrants make up
1/4 of the dentition
Mesial
Toward midline
Distal
Away from midline
Lingual
Inside, toward tongue
Labial
Outside toward lips
Incisal
Biting or cutting edge
Buccal
Outside, toward cheeks
Occlusal
Grinding or chewing surface
Major elevation on the masticatory surfaces of the canines and posterior teeth
Cusp
Fossa
Wide shallow depression on the lingual surfaces of anterior teeth and occlusal surfaces of posterior teeth
Raised, rounded area on the cervical third of the lingual surface.
Cingulum
Ridge
Thin elongated surface
Mamelon
Rounded enamel extensions on the incisal edge of newly erupted incisors
The 5th supplemental cusp found lingual to the mesiolingual cusp
Cusp of carabelli
Central groove
Most prominent groove on posterior teeth
Function of the incisor
Cut food without heavy force
Canines
Cutting and tearing of food with force
Premolars
Grasping, tearing, grinding
Molars
Chew and grind food
3 anatomical features of teeth are
Contours, contacts and embrasures
Contour is
Crown of the tooth which narrows towards the cervical line
The mesial or distal surface of a tooth that touches the adjacent tooth in the same arch
Contact area
Contact point
Exact spot at which the teeth actually touch each other
Contacts do what?
Prevent food impact ion, protects interproximal tissues and stabilizes the arches
An embrassure is what
Is a triangular space between the proximal surfaces of two adjoining teeth in contact
A line angle is a junction of how many walls
2
A point angle is formed by the junction of how many surfaces
3
Both primary and permanent anterior teeth have how many roots
1
All premolars/bicuspids have how many roots. The exception is the max. First pre molar and it has how many?
Premolars/bicuspids have 1
Max first premolar has 2
All max molars have how many well formed & separated roots? except for the third molar
3
All mand molars have how many well formed & separated roots?
2
What are the 3 tooth numbering systems
Universal, international/FDI and Palmer
What does MODBL stand for
Mesio-occluso-disto-bucco-lingual
OB stands for
Occlusobuccal
Date of eruption for a central incisor
6-10months
Date of eruption for lateral incisor
9-12 months
Date of eruption for first molar
12-18 months
Date of eruption for canine
16-22 months
Date of eruption for second molar
24-32 months
Habits such as thumb sucking or improper swallowing habit can affect
Occlusion
Centric occlusion
Jaws are closed in a position that produce maximal stable contact between the occluding surfaces of the max and mand teeth
Functional occlusion
Contact of the the teeth during biting and chewing movements
Malocclusion
Abnormal relationship of the teeth
Normal occlusion is when
Mesiobuccal cusp of permanent maxillary first molar occluded with mesiobuccal groove of the mandibular first molar
Maxillary canine occluded with distal half of mand canine and the mesial half of the mand premolar
Normal occlusion
Basis of angles classification system is that
The permanent maxillary first molar is the key to occlusion
There are three classifications of occlusion
Class 1 Class 2 which is split into division 1 and 2 And class 3
Class 1 occlusion is knows as a
Neutroclusion
Neutroclusion is when
The mesiobuccal cusp of permanent maxillary first molar occluded with the mesiobuccal groove of the mandibular first molar
Also known as crooked teeth caused by crowding or spacing
Class 2 is known as
Distoclusion
Distoclusion is when
Mesiobuccal cusp of permanent maxillary first molar occluded mesial to the mesiobuccal groove of the mandibular first molar
Also known as an overbite
Class 3 is known as
Mesioclusion
Mesioclusion is when
Mesiobuccal cusp of permanent maxillary first molar occludes distal to the mesiobuccal groove of the mandibular first molar
Also known as an underbite
Curve of spee
What is the name for the arc of the occlusal plane
Curve of Wilson
Defined by a line drawn across the occlusion surface of the left mandibular first molar across the arch and through the occlusal surface of the right mandibular first molar
Antagonist
Every tooth in the oral cavity has 2 antagonists EXCEPT THE MANDIBULAR central incisors and maxillary 3rd molars
Cavity class 1
Occlusal on posteriors and lingual out of anteriors
Cavity class 2
Proximal surfaces of posteriors
In between sides touching other teeth, hard to see
Cavity class 3
Proximal surfaces of incisors and canines
same as 2 just on different teeth
Cavity class 4
Proximal surfaces of incisors and canines, similar to class 3 except it includes the incisal edge
Cavity class 5
Gingival third of the facial or lingual surface of any tooth
Near base of tooth above gums
Cavity class 6
Incisal edges of anterior teeth
Cusp tips of posterior teeth
Appears as lesions on biting surface of teeth