ANATOMY OF OROFACIAL STRUCTURES
9TH EDITION STUDY GUIDE 2026
COMPREHENSIVE QUESTIONS AND STEP
BY STEP SOLUTIONS
◉ why does a mesial step occur ?
Answer: allows room for the lower molars to move mesially
◉ premolars are not as wide as
Answer: primary molars
◉ what is extra space called
Answer: leeway space
◉ what helps the mandibular teeth before the maxillary teeth help
establish the mesial step?
Answer: earlier eruption
◉ what is the development of occlusion influneced by?
Answer: hereditary factors: missing teeth, impacted teeth, size and
shape of muscle and bone
,◉ what are controllable factors that affect occlusal development
Answer: premature loss of deciduous teeth, decayed teeth , harmful
habits
◉ what is horizontal alignment
Answer: balance or equilibrium between the tongue and the facial
muscles
◉ what does horizontal alignment allow?
Answer: teeth to be brought into proper alignment and be
maintained in their proper positions once they have erupted
◉ what happens if horizontal alignment is disturned?
Answer: a malocclusion or an abnormal alignment of the teeth
within the dental arches can occur
◉ what happens after the teeth erupt?
Answer: tongue acts as an internal force, pushing teeth toward the
lips and cheeks
◉ what do we call the muscles that allow the cheeks and lips prevent
the teeth from moving too far facially ?
, Answer: resistance
◉ what can abnormal thrusting of the tongue aganist the anterior
teeth cause?
Answer: imbalanced state
◉ what does tongue thrusting cause?
Answer: the maxillary anterior teeth to protrude labially
◉ what does intercuspation of the teeth help prevent?
Answer: tooth deviations in a buccal or lingual direction
◉ what does alignment with previously eruopted teeth affect?
Answer: successive teeth
◉ what is adequate space needed for?
Answer: needed between teeth to allow for complete eruption of
more teeth
◉ what happens when a tooth does not have room enough?
Answer: it will erupt out of alignment
9TH EDITION STUDY GUIDE 2026
COMPREHENSIVE QUESTIONS AND STEP
BY STEP SOLUTIONS
◉ why does a mesial step occur ?
Answer: allows room for the lower molars to move mesially
◉ premolars are not as wide as
Answer: primary molars
◉ what is extra space called
Answer: leeway space
◉ what helps the mandibular teeth before the maxillary teeth help
establish the mesial step?
Answer: earlier eruption
◉ what is the development of occlusion influneced by?
Answer: hereditary factors: missing teeth, impacted teeth, size and
shape of muscle and bone
,◉ what are controllable factors that affect occlusal development
Answer: premature loss of deciduous teeth, decayed teeth , harmful
habits
◉ what is horizontal alignment
Answer: balance or equilibrium between the tongue and the facial
muscles
◉ what does horizontal alignment allow?
Answer: teeth to be brought into proper alignment and be
maintained in their proper positions once they have erupted
◉ what happens if horizontal alignment is disturned?
Answer: a malocclusion or an abnormal alignment of the teeth
within the dental arches can occur
◉ what happens after the teeth erupt?
Answer: tongue acts as an internal force, pushing teeth toward the
lips and cheeks
◉ what do we call the muscles that allow the cheeks and lips prevent
the teeth from moving too far facially ?
, Answer: resistance
◉ what can abnormal thrusting of the tongue aganist the anterior
teeth cause?
Answer: imbalanced state
◉ what does tongue thrusting cause?
Answer: the maxillary anterior teeth to protrude labially
◉ what does intercuspation of the teeth help prevent?
Answer: tooth deviations in a buccal or lingual direction
◉ what does alignment with previously eruopted teeth affect?
Answer: successive teeth
◉ what is adequate space needed for?
Answer: needed between teeth to allow for complete eruption of
more teeth
◉ what happens when a tooth does not have room enough?
Answer: it will erupt out of alignment
