Dentistry Flashcards
Enamel
Outer covering of crown that has no sensory capacity, elasticity, or flexibility
Hardest portion of the tooth
Dentin
Makes up the bulk of the tooth
Second hardest tissue in the body
Sensitive to heat, cold, and touch
Pulp
Interior cavity
Rich with blood vessels, nerves, and lymphatics
Registers pain and quickly becomes contaminated, inflamed, and necrotic if exposed
Cementoenamel Junction (CEJ)
junction between the crown and the root
Periodontium
Tooth supporting structure
Collection of supporting structures surrounding the teeth
Cementum
Avascular and bonelike material that covers the root
Attached to the bone by periodontal ligament fibers
Constantly undergoing resorption and repair
Periodontal Ligament
Holds the tooth in the alveolus by attaching the tooth to the alveolar bone
Absorbs shock of impact, protects vessels and nerves, registers pain and tactile pressure, and supplies nutrients to alveolar bone and cementum
Alveolar Bone
Surrounds and supports the teeth
Constantly remodeling internally yet remains constant throughout adult life
Osteoblasts vs Osteoclasts
Osteoblasts - cells that make bone
Osteoclasts - cells that resorb bone
Gingiva
Soft tissue providing epithelial attachment
first line of defense
Free gingiva
most coronal gingiva, is not directly attached to the tooth, and forms the sulcus
Attached gingiva
Apical to free gingiva
Crown
Portion above the CEJ, visible to the naked eye, and covered in enamel
Root
Portion below the CEJ that is mainly made of dentin and covered by cementum
Heterodont
teeth of mixed form and function
Diphyodont
Having a set of primary (deciduous) teeth and secondary (permanent) teeth
Anelodont
Having a limited period of growth as they develop roots
Brachyodont
Having a root that is longer than the crown
Hypsodont
Having a long crown and a short root
Much of the crown is held in reserve subgingivally in the alveolar bone
Elodont
Teeth that grow throughout life and never develop roots
Dog and Cat Teeth Types
Heterodont, diphyodont dentition with anelodont, brachyodont teeth
Horse Teeth Types
Heterodont, diphyodont dentition with anelodont, hypsodont teeth
Rabbit Teeth Types
Heterodont, diphyodont dentition with elodont teeth, the deciduous teeth are not functional and are exfoliated shortly before or after birth
Incisor
6 incisors in the maxilla and 6 incisors in the mandible
Function: tearing, nibbling, and grooming
-Each only have one root
101-103, 201-203, 301-303, 401-403
Canine
2 canine teeth in the maxilla and 2 in the mandible
Function: to grab and tear food and for protection
-Each have only one root which is longer than the crown for protection
-Most prone to fracture due to amount of trauma the tooth is subjected to
104, 204, 304, and 404
Premolar
Located behind the teeth
Function: to hold and cut food into digestible pieces
Dogs have 8 premolars in the maxilla and 8 in the mandible
Cats have 6 in the maxilla and 4 in the mandible
Maxilla premolars have one, two, or three roots while mandible premolars have one or two roots
Molar
Located behind the premolars
Function: to grind food
In cats, there are 2 in the maxilla and 2 in the mandible with the molars having 1 or 2 roots
In dogs, there are 4 in the maxilla and 8 in the mandible with the molars having 2 or 3 roots
Carnassial Teeth
Cheek teeth found in carnivorous teeth
Function: to shear flesh and bone
In the dog and cat, the carnassial teeth are the upper fourth premolar and the lower first molar
Directional Terms - Facial
towards the face (also called “labial” for anteriors and “buccal” for posteriors
Directional Terms - Lingual
towards tongue (also called “palatal” for maxillary teeth)
Directional Terms - Palatal
towards the palate on the maxillary teeth
Directional Terms - Mesial
towards midline
If you are nose to nose with the patient, the mesial root is the root closest to you
Directional Terms - Distal
away from midline
If you are nose to nose with the patient, the distal root is the root more distant to you
Directional Terms - Rostral
towards nose of animal
Directional Terms - Buccal
towrds the cheeks
Furcation Definition
space between 2 roots where they meet the crown
Incisal
biting surface of incisors
Occlusal
chewing surface
Coronal
towards crown
Apical
towards roots
Contact Area
Area that touches the adjacent tooth in the same arch
If not present, teeth have an open contract
Interproximal space
area between adjacent teeth
Characteristics of a normal occlusion (also called “scissor bite”)
Upper incisors just overlap the lower incisors
Lower canines fit between upper third incisor and upper canine
Interdigitation of upper and lower premolars (side view)
Neutrocclusion (Class 1 Malocclusion; MAL/1)
Jaw lengths are normal, but one or more teeth are in an abnormal position
Distoversion
A tooth in its anatomically correct position in the dental arch but abnormally angled in a distal direction
Mesioversion
A tooth in its anatomically correct position in the dental arch but abnormally angled in a mesial direction
Linguoversion
A tooth in its anatomically correct position in the dental arch but abnormally angled in a lingual direction
Labioversian
An incisor/canine tooth in its anatomically correct position in dental arch but abnormally angled in a labial direction
Buccoversian
A premolar/molar in its anatomically correct position in the dental arch but abnormally angled in a buccal direction
Crossbite
Mandibular tooth/teeth present a more buccal or labial position that the antagonist maxillary tooth
Can be classified as rostral or caudal
Rostral crossbite
Mandibular incisor teeth are labial to the opposing maxillary incisor teeth when mouth is closed
Caudal crossbite
Mandibular cheek teeth are buccal to the opposing maxillary cheek teeth when mouth is closed
Mandibular Disocclusion (Class 2 Malocclusion; MAL/2)
Overjet
Mandible resides distal (caudal) to its normal location in relation to maxilla
*Often results in mandibular canine teeth traumatizing the palate
Mandibular Mesiocclusion (Class 3 Malocclusion; MAL/3)
Underjet
Mandible resides mesial (rostral) to its normal location in relation to the maxilla
*Although considered normal in brachycephalic breeds, maxillary incisors that contact the lingual floor or canine teeth can cause significant trauma/discomfort
When do primary teeth generally erupt or emerge into the oral cavity?
3-6 weeks
At 3 months of age, the ____ begin to erupt, and the ____ are shed or exfoliated
Permanent teeth
Primary teeth
Deciduous teeth are fully erupted by ____, and usually by _____ they are replaced by permanent (secondary or adult teeth)
2 months of age
6 months
List the order of primary teeth eruptions in dogs
Canines first then incisors then fourth, third, and second premolars for total of 28 primary teeth
List the order of primary teeth eruptions in cats
Incisors before canines followed by premolars for a total of 26 deciduous teeth
What happens to deciduous teeth as permanent teeth develop?
Resorption causes the roots of the deciduous teeth to be absorbed by the surrounding tissues (also called exfoliation) and usually is complete by 6 months of age
What is a period of mixed dentition?
Time when the mouth contains both primary and permanent teeth in functional positions
Name the canine dental formula
2x (3/3 I, 1/1 C, 4/4 P, 2/3 M) = 42
Name the feline dental formula
2x (3/3 I, 1/1 C, 4/4 P, 2/3 M) = 30
*The upper first premolar and the lower first and second premolar are absent
List the deciduous formulas for both cats and dogs and why are they different from the permanent teeth dental formula?
Dog: 2x (3/3 I, 1/1 C, 3/3 P) = 28
Cat: 2x (3/3 I, 1/1 C, 3/2 P) = 26
*There are no deciduous counterparts for the first premolar or the molars
What causes delayed eruption of permanent teeth? What breeds of dog are predisposed? How is diagnosis confirmed?
Delay usually caused by dense, overlying, fibrous gingival tissue preventing normal eruption
Small-breed dogs are typically pre-disposed
Diagnosis is confirmed by x-ray
Define operculectomy
Performed by removing a small gingival window with No. 11 surgical blade to remove the impediment
Which are the most common retained (persistent) deciduous teeth and how are they treated?
Canines followed by incisors and premolars
Immediate extraction of the retained tooth
How are missing, underlying permanent teeth treated?
Once resorption is clinically or radiographically evident, extraction is indicated
What causes deciduous teeth to fracture and what is treatment for them?
The roots of deciduous teeth are longer and thinner and may be partially resorbed, so treatment involves extraction because of the risk for infection due to exposed pulp
Explain the Modified Triadian System
Each tooth is given a 3-digit number
First number represents the quadrant
Second and third numbers represent the actual tooth within the arcade
List the Permanent (adult) teeth quadrant numbers
1 (right maxilla)
2 (left maxilla)
3 (left mandible)
4 (right mandible)
List the Primary (baby) teeth quadrant numbers
5 (right maxilla)
6 (left maxilla)
7 (left mandible)
8 (right mandible)
Explain the Rule of 4 and 9
Tooth 4 is always the canine tooth and tooth 9 is always the first molar
Which teeth are cats missing?
105, 205, 305, 405, 306, and 406
Explain the tooth anatomic identification system
Uppercase letters indicate permanent teeth
Lowercase letters indicate deciduous teeth (primary teeth)
Superscript: maxillary teeth
Subscript: mandibular teeth
