Transverse Problems

Question 1

Anterior Crossbite
* Prevalence:—%
* Manifested in the — dentition

Answer 1

2.2% to 11.9
mixed

Question 2

No Treatment?
(5)

Answer 2

• Esthetic problem
• Damage to the teeth in crossbite
  through attrition
• Gingival recession
• Loss of alveolar bone on lower incisors
• Excess mobility of lower incisors
  affected by the crossbite

Question 3

Differential Diagnosis
(4)

Answer 3

• Cephalometric evaluation
• Dental assessment
• Functional assessment
• Profile analysis

Question 4

Differential Diagnosis
Ngan, et al., Pediatric Dednitry, 1997
* Dental assessment
* Class III molar relationship

Answer 4

• (-) overjet or end-to-end relationship with retroclined mandibular incisors (compensated
  class III malocclusion)
• If negative overjet, proceed to functional assessment

Question 5

• Functional assessment
• Determine whether a — discrepancy exist

Answer 5

centric relation/centric occlusion (CR/CO)

Question 6

• Functional assessment
• At CR, patient may have a Class — skeletal pattern, normal facial profile and Class —
  molar relationship
• At CO, patient may have a Class — skeletal and dental pattern

Answer 6

I, I
III

Question 7

ANTERIOR
CROSSBITE
SKELETAL
Ceph:
Dental:
Profile:

Answer 7

Class III maxillo-mandibular
relationships

Severe proclination of upper
incisors
Severe retroclination of lower
incisors
Class III molar relationship
**MAY or MAY NOT be
present in Class III skeletal

Concave or straight **MAY
or MAY NOT be present in Class III skeletal

Question 8

ANTERIOR
CROSSBITE
DENTAL
Ceph:
Dental:
Profile:

Answer 8

Class I or II maxillo-mandibular
relationships

Normal inclination/position or
severe retroclination/retrusion
of upper incisors
Severe proclination/protrusion
of lower incisors
Class I or II molar relationship
Presence of anterior functional
shift
*MAY or MAY NOT be
present in Class III dental

Straight or convex

Question 9

Early Treatment of dental
anterior crossbite
* The most common etiologic factor for nonskeletal anterior crossbites is
…
* Focus the treatment plan on management of the total space situation, not
just the crossbite

Answer 9

lack of space for the permanent incisors

Question 10

Early Treatment of dental
anterior crossbite
Management
(4)

Answer 10

• Extraction of adjacent primary teeth to provide necessary space
• Disking of teeth
• Opening space for tooth movement
• Determine whether tipping will provide appropriate correction

Question 11

Early Treatment of dental
anterior crossbite
(3)

Answer 11

• Fixed inclined planes
• Reverse crown
• Maxillary lingual holding arch with springs

Question 12

• Reverse crown
  (2)

Answer 12

• A large permanent anterior tooth crown is
• reverse-cemented

Question 13

• Maxillary lingual holding arch with springs
  (2)

Answer 13

• Lingual eruption of maxillary lateral incisors in
• a crowded arch

Question 14

Early Treatment of skeletal
anterior crossbite
* Must refer to orthodontist
* Objective is to

Answer 14

reduce the amount of dental compensation to skeletal;
discrepancy that are often associated with a more severe malocclusion in
late adolescence

Question 15

Posterior Crossbite
Iodice, et al., Eur.J. Orthod. 2013; Contemporary Orthod. 5th Ed.
* Prevalence:
* –% of Hispanic population
* –% in African-American population
* –% among Caucasians
* Transverse maxillary deficiency:

Answer 15

7.3
9.6
9.1
narrow
maxilla relative to the rest of the face

Question 16

Hidden Posterior Crossbite
* Compensatory changes in dentoalveolar
processes
(3)

Answer 16

• Tipping of maxillary teeth to the buccal
• Tipping of mandibular teeth to the lingual
• Uprighting teeth creates a dental crosbite

Question 17

Unilateral Posterior
Crossbite
* May be a bilateral crossbite with a
functional lateral jaw shift as the
teeth from centric relation to centric
occlusion
* Key sign:

Answer 17

deviation of the mandibular
dental midline, relative to the
maxillary dental and skeletal midlines,
toward the side of the crossbite when
the teeth are in maximum
intercuspation

Question 18

Posterior Crossbites due to
functional shifts
Sequelae:
(4)

Answer 18

1. Compensatory changes in
   the TMJ?
2. Modifications of soft tissue
   growth?
3. Development of skeletal
   asymmetries?
   NO STRONG EVIDENCE
4. Attrition of teeth

Does not self

Question 19

skipped
Posterior Crossbites
management
(7)

Answer 19

• Is the crossbite skeletal or dental?
• Is the crossbite unilateral or bilateral
• Is there a functional shift?
• If dental, which teeth are tipped and in which jaws?
• Should the treatment be initiated at this time or deferred to a later date?
• Should the problems be corrected?
• Can the problem be corrected or masked by treatment?

Question 20

Management
* Simple dentoalveolar unilateral posterior
crossbite:

Answer 20

fixed or removable appliances
to move teeth
* W-arch, quadhelix (up to age 9 or 10)
* Jackscrew: relatively heavy force
that separates the partially
interlocked suture

Question 21

Posterior Crossbites
management
* Early mixed dentition:

Answer 21

use
slow expansion
* Suture can be separated in
females up to age 16, and in
males up to age 18
* An occlusal radiograph is used
to assess the midpalatal
suture patency

Question 22

Buccal Crossbites
(scissor bite)
(2)

Answer 22

• Buccal displacement of a maxillary posterior tooth, with or without
  contact between the lingual surface of the maxillary lingual cusp and the
  buccal surface of the mandibular antagonist’s buccal cusp.
• A complete buccal crossbite (Brodie bite): a combination of excessive
  maxillary width and a narrow mandibular alveolar process, although the
  width of the mandibular base is usually normal.

Question 23

Scissor bite
(3)

Answer 23

• Elastics
• Mandibular appliance to upright
  posterior teeth
• Lip bumper