Orthodontics Assistant Final Exam: Questions With Expert
Solutions
What occurs during first appointment? Right Ans - Initial exam and
interview
X-rays
Impressions for study models
Treatment plan
What type of records are used in an orthodontics practice? Right Ans -
Clinical photos I/E. E/O
Radiographs: Lateral Ceph, OPG, Cone Beam
Plaster Models
Which reference points are used to assess facial symmetry? Right Ans -
Facial midline through glabella & philtrum
Pupillary midline
Where is facial asymmetry commonly found? Right Ans - Rarely maxilla:
Chin
Mandibles
angles and
Cheekbones
What reference points are used for facial convexity? Right Ans - Glabella
Subnasal
pogonion (anterior point of chin)
What type of malocclusion is indicated by convex? Right Ans - Class II
What type of malocclusion is indicated by concave? Right Ans - Class III
(hypoplastic maxilla)
What is Brachyfacial? Right Ans - Broad square face
Low mandibular plane angle
Strong chin
Straight profile
Flat lip posture
,What is Dolicofacial? Right Ans - Long narrow face
High mandibular plane angle
Convex
Poor chin development
anterior, posterior face height imbalance
What is mesofacial? Right Ans - Well balanced i.e. equal thirds
What does a negative discrepancy, in spacing measured with calipers
indicate? Right Ans - Crowding
What is molar Class I malocclusion? Right Ans - MB cusp of upper 6 should
rest on MB groove on lower 6
What is Class II molar malocclusion? Right Ans - MB Cusp of upper 6 is
mesial to MB groove of lower 6
What is Class III molar malocclusion Right Ans - MB cusp of upper 6 is
positioned distal to the MB groove of lower 6
What is overbite? Right Ans - Vertical overlap of incisors - normal is 1-
2mm
What is open bite? Right Ans - No vertical overlap of incisors
What is a deep bite? Right Ans - Vertical overlap of incisors measured as a
percentage
What is overjet? Right Ans - Horizontal overlap of incisors
What is normal overjet? Right Ans - 2-3mm
What is anterior crossbite? Right Ans - Lower anteriors are in front of
upper incisors
What is a posterior cross bite? Right Ans - Mandibular posterior teeth are
buccal positioned in relation to Maxillary, reflects narrow max arch
, What is CR-CO? Right Ans - The relationship between Centric Relation and
Centric Occlusion
What are the steps of Diagnosis and Tx Planning? Right Ans - 1. Develop
adequate diagnostic database
2. Formulate problem list (diagnoses)
3. Prioritise problems on list
4. Evaluate Interactions between solutions
5. Evaluate alternative solutions
6. Develop final treatment concept with Pt. input
What are indications for Orthodontic Tx? Right Ans - 1.Alleviate social
handicap
2. Enhance Dental and Facial appearance
3. Maintain normal development
4. Improve Jaw function
5. Reduce trauma on dentition and soft tissue
6. Facilitate other Dental Tx (e.g. implants)
What is the Field theory? Right Ans - Explains usual pattern of hypodontia
where for any given field (Incisors, canines, PM and M), the most distal tooth
is most likely to experience hypodontia e.g. laterals, 5s, 8s
How can a posterior crossbite be treated? Right Ans - Expanders
How is excessive overjet treated? Right Ans - Removable appliance if just
teeth
Specialists if associated with skeletal component
What needs to be done if a primary tooth is extracted or prematurely lost for
any reason? Right Ans - A space maintainer e.g. a ring and clamp/band and
loop
What should be used if molars on both sides are lost? Right Ans - A
lingual/palatal arch
What exception is there to the placement of spacers in prematurely lost
primary teeth? Right Ans - Incisors do not need space maintainers
Solutions
What occurs during first appointment? Right Ans - Initial exam and
interview
X-rays
Impressions for study models
Treatment plan
What type of records are used in an orthodontics practice? Right Ans -
Clinical photos I/E. E/O
Radiographs: Lateral Ceph, OPG, Cone Beam
Plaster Models
Which reference points are used to assess facial symmetry? Right Ans -
Facial midline through glabella & philtrum
Pupillary midline
Where is facial asymmetry commonly found? Right Ans - Rarely maxilla:
Chin
Mandibles
angles and
Cheekbones
What reference points are used for facial convexity? Right Ans - Glabella
Subnasal
pogonion (anterior point of chin)
What type of malocclusion is indicated by convex? Right Ans - Class II
What type of malocclusion is indicated by concave? Right Ans - Class III
(hypoplastic maxilla)
What is Brachyfacial? Right Ans - Broad square face
Low mandibular plane angle
Strong chin
Straight profile
Flat lip posture
,What is Dolicofacial? Right Ans - Long narrow face
High mandibular plane angle
Convex
Poor chin development
anterior, posterior face height imbalance
What is mesofacial? Right Ans - Well balanced i.e. equal thirds
What does a negative discrepancy, in spacing measured with calipers
indicate? Right Ans - Crowding
What is molar Class I malocclusion? Right Ans - MB cusp of upper 6 should
rest on MB groove on lower 6
What is Class II molar malocclusion? Right Ans - MB Cusp of upper 6 is
mesial to MB groove of lower 6
What is Class III molar malocclusion Right Ans - MB cusp of upper 6 is
positioned distal to the MB groove of lower 6
What is overbite? Right Ans - Vertical overlap of incisors - normal is 1-
2mm
What is open bite? Right Ans - No vertical overlap of incisors
What is a deep bite? Right Ans - Vertical overlap of incisors measured as a
percentage
What is overjet? Right Ans - Horizontal overlap of incisors
What is normal overjet? Right Ans - 2-3mm
What is anterior crossbite? Right Ans - Lower anteriors are in front of
upper incisors
What is a posterior cross bite? Right Ans - Mandibular posterior teeth are
buccal positioned in relation to Maxillary, reflects narrow max arch
, What is CR-CO? Right Ans - The relationship between Centric Relation and
Centric Occlusion
What are the steps of Diagnosis and Tx Planning? Right Ans - 1. Develop
adequate diagnostic database
2. Formulate problem list (diagnoses)
3. Prioritise problems on list
4. Evaluate Interactions between solutions
5. Evaluate alternative solutions
6. Develop final treatment concept with Pt. input
What are indications for Orthodontic Tx? Right Ans - 1.Alleviate social
handicap
2. Enhance Dental and Facial appearance
3. Maintain normal development
4. Improve Jaw function
5. Reduce trauma on dentition and soft tissue
6. Facilitate other Dental Tx (e.g. implants)
What is the Field theory? Right Ans - Explains usual pattern of hypodontia
where for any given field (Incisors, canines, PM and M), the most distal tooth
is most likely to experience hypodontia e.g. laterals, 5s, 8s
How can a posterior crossbite be treated? Right Ans - Expanders
How is excessive overjet treated? Right Ans - Removable appliance if just
teeth
Specialists if associated with skeletal component
What needs to be done if a primary tooth is extracted or prematurely lost for
any reason? Right Ans - A space maintainer e.g. a ring and clamp/band and
loop
What should be used if molars on both sides are lost? Right Ans - A
lingual/palatal arch
What exception is there to the placement of spacers in prematurely lost
primary teeth? Right Ans - Incisors do not need space maintainers
