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Articulation and Resonance Lab 2
Dentition (Noncadaver Lab)
To the Instructor: This lab is best performed using dental impressions, especially if they show
pre-orthodontia malocclusions and other malformations. Dental labs, dentists, and dental
hygienists are great sources of these impressions, which are wonderful study guides for your
students. You’ll probably find that individual students will donate their impressions when they
see how much good they do. This lab guide gives you general terms and discussion points. You
may wish to add some of the following images from the Image Library to the lab guide so that
students will have them at hand as a reference in the lab.
Figure or Table
Figure 6-23a Upper and lower arches
Figure 6-23 b–e Dental malocclusion secondary to dental malformations
Figure 6-29 b
and c Dental malocclusion secondary to prognathic mandible and orofacial
myofunctional disorders
Figure 6-23b Photo of adult arch
Figure 6-24 Landmarks of tooth
Figure 6-25 Surface references of teeth and dental arch
Figure 6-26 Types of teeth
Figure 6-27a Comparison of deciduous and permanent arches
Figure 6-27b Panaflex of emergent permanent teeth in deciduous arch
Figure 6-28 Terms of occlusion
Table 6-2 Terms of malocclusion
Figure 6-29a Terms of malorientation
Figure 6-29b Radiograph of prognathic mandible
Figure 6-29c Dental impressions revealing marked malorientations secondary to
tongue thrust
Articulation and Resonance Lab 2
Dentition (Noncadaver Lab)
You will want to familiarize yourself with the terminology, spelling, structures, and landmarks
indicated next.
Generally:
incisors
molars
Structure:
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neck: juncture of root and crown
dentin: ivory of tooth; bulk of tooth; calcified tissue; contains nerves in pulp
enamel: very dense, hardest substance in body; covers crown to root (not on root); resists
abrasion; thickest on grinding surface
Types of teeth:
central incisors: chisel-shaped; have only one root; lower smaller than upper; lower are
overlapped by uppers
lateral incisors: smaller than centrals; shorter root than centrals
Tooth development:
Growth period:
formation of tooth bud (five weeks embryonic)
deposition of enamel and dentin (seven weeks embryonic)
Calcification:
enamel and dentin hardened by calcium
Arches:
adult = 8 per half arch; child = 5 (missing 2 bicuspids, 1 molar)
Deciduous arch:
smaller and fewer
ten teeth in each arch
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©2016 Cengage Learning. May be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part.
start getting teeth in at six to seven months; finish by end of second year
start shedding at six to seven years
healthy deciduous arches necessary for correct spacing of permanent teeth
Permanent arch:
successional teeth: those replacing deciduous
successionals are mature by the time deciduous erupt
when ready to erupt, they push up to contact deciduous; osteoclasts develop at point of
contact
Class I malocclusion: normal molar orientation but deviation in anterior portion of arch
Class II malocclusion: mandible retruded or retracted (relative micrognathia)
Class III malocclusion: mandible overlaps maxilla (protruded mandible)
persistent open bite: cannot occlude in front
persistent closed bite: cannot occlude posterior teeth