Evaluation of Face and Terminology Flashcards
Primary teeth letters
a = central b = laterals c = cuspid d = 1st primary molar e = 2nd primary molar
Permanent teeth numbers
1 = centrals 2 = laterals 3 = cuspid 4 = 1st bicuspid 5 = 2nd bicuspid 6 = 1st molar 7 = 2nd molar 8 = 3rd molar
Mixed Dentition
Classic: 12cde6
Early: 1bcde6
Late: 1234e6
Overbite
vertical measurement of the amount of overlap the incisors
of lower incisor clinical crown, look for lower incisor impingement on palatal tissues
Normal is about 10%
Overjet
horizontal measurement from the labial of the maxillary central incisor to the labial of the mandibular central incisor
normal is 2-4 mm
excess does not mean Class II and inadequate does not mean class III
Inadequate (negative) = cross-bite
Arch Length (common) and Arch Circumference (proper)
distance in mm from the mesial of the 1st permanent molar around arch over the contact points and incisal edges to the mesial of the 1st permanent molar on opp. side
Arch Length
distance from a line perpendicular to the mesial surface of the permanent first molars to the central incisors
Arch circumference
distance in mm from mesial of the 1st permanent molar around the arch over the contact points and incisal edges to the mesial of the 1st permanent molar on the opp. side
Space Required
mesiodistal width at the normal contact point of each erupted permanent tooth anterior to the first permanent molar (sum the widths)
Compare space allowed with space required
If SR > SA, the patient has crowding or a “tooth size arch length” discrepancy (TSAL)
If SA > SR, pt has excess space
Vertical Facial Proportions
Facial 1/3s
Lower facial 1/3 slightly longer than central 1/3
Lower 1/3 divided 1/3 to 2/3
Frontal Facial Proportions
Separation of eyes = width of eyes
Central, medial, and lateral 1/5s
Nose, chin centered in central 1/5, nose same or slightly sider
Interpupillary width = width of mouth
Skeletal Profile
Frankfort horizontal plane (porion-orbitale) vs nasion-porion line
Straight: soft tissue N-Pog line is approximately 90 degrees compared to the Po-Or (Frankfort Horizontal) line
Retrognathic: soft tissue pogonion point is behind a 90 degree line extending from Nasion compared to Frankfort Horizontal
Prognathic: pogonion point is anterior to the 90 degree line extending from Nasion compared to the FH
Skeletal Profile pt 2
2 lines from bridge of nose to base of upper lip
Straight = class I skeletal Convex = class II skeletal Concave = Class III skeletal
How to measure mandibular plane
mirror handle on border of mandible
flat = short face, deep bite steep = long face, open skeletal bite
