#DEN4001
#D4/S1/W11
#ORTHO

Recognition of Malocclusion

Ortho assessment

• The patient’s and/or carer’s awareness of the malocclusion (presenting complaint)
• Their general level of dental awareness
• An extra-oral examination of facial form (skeletal pattern and soft tissue)
• General oral condition – oral hygiene and tooth quality
• Presence of all or absence of teeth
• The alignment and form of each arch
• The teeth in occlusion
• Radiographic assessment – orthopantogram
• Good quality study models
• Clinical photographs.

IOTN

• two components
  • dental health
  • aesthetic

Dental health component

• Grade 1 - no need for treatment
• Grade 2 - slight need for treatment
• Grade 3 – borderline  need for treatment
• Grade 4 -  need for treatment
• Grade 5 -  great need for treatment
• following characteristics are assessed, most severe trait in the grade selected
  • missing teeth
  • overjet
  • crossbite
  • contact point displacement
  • overbite

Grade 1 (None)

• 1 Extremely minor malocclusions including contact point displacements less than 1 mm.

Grade 2 (Slight)

• 2a. Increased overjet greater than 3.5 mm, but less than or equal to 6 mm with competent lips.
• 2b. Reverse overjet greater than 0 mm but less than or equal to 1 mm.
• 2c. Anterior or posterior crossbite with less than or equal to 1 mm discrepancy between retruded contact position and intercuspal position.
• 2d. Contact point displacements greater than 1 mm but less than or equal to 2 mm.
• 2e.  Anterior or posterior open bite greater than 1 mm but less than or equal to 2 mm.
• 2f.   Increased overbite greater than or equal to 3.5 mm without gingival contact.
• 2g.  Pre- or post-normal occlusions with no other anomalies (includes up to half a unit  discrepancy).

Grade 3 (Borderline need)

• 3a. Increased overjet greater than 3.5 mm, but less than or equal to 6 mm with incompetent lips.
• 3b. Reverse overjet greater than 1 mm, but less than or equal to 3.5 mm.
• 3c. Anterior or posterior crossbites with greater than 1 mm, but less than or equal to 2 mm discrepancy between retruded contact position and intercuspal position.
• 3d. Contact point displacements greater than 2 mm, but less than or equal to 4 mm.
• 3e. Lateral or anterior open bite greater than 2 mm, but less than or equal to 4 mm.
• 3f. Deep overbite complete on gingival or palatal tissues, but no trauma.

Grade 4 (Need treatment)

• 4h. Less extensive hypodontia requiring pre-restorative orthodontics or orthodontic space closure to obviate the need for a prosthesis.
• 4a. Increased overjet greater than 6 mm, but less than or equal to 9 mm.
• 4b. Reverse overjet greater than 3.5 mm with no masticatory or speech difficulties.
• 4m. Reverse overjet greater than 1 mm but less than 3.5 mm with recorded masticatory and speech difficulties.
• 4c. Anterior or posterior crossbites with greater than 2 mm discrepancy between retruded contact position and intercuspal position.
• 4l. Posterior lingual crossbite with no functional occlusal contact in one or both buccal segments.
• 4d. Severe contact point displacements greater than 4 mm.
• 4e. Extreme lateral or anterior open bites greater than 4 mm.
• 4f. Increased and complete overbite with gingival or palatal trauma.
• 4t. Partially erupted teeth, tipped and impacted against adjacent teeth.
• 4x. Presence of supernumerary teeth.

Grade 5 (Great Need treatment)

• 5I. Impeded eruption of teeth (except for third molars) due to crowding, displacement, the presence of supernumerary teeth, retained deciduous teeth and any pathological cause.
• 5h. Extensive hypodontia with restorative implications (more than 1 tooth missing in any quadrant) requiring pre-restorative orthodontics.
• 5a. Increased overjet greater than 9 mm.
• 5m.Reverse overjet greater than 3.5 mm with reported masticatory and speech difficulties.
• 5p. Defects of cleft lip and palate and other craniofacial anomalies.
• 5s. Submerged deciduous teeth.

Aesthetic component

• 10 photographs showing different levels of dental attractiveness
• grades 1-4 - little or no treatment on aesthetic grounds
• grades 5-7 - borderline need for treatment
• grades 8-10 - would clearly benefit from orthodontic treatment

Ortho referral

• refer earlier rather than later
• include likely compliance of family to orthodontic treatment
• oral hygiene
• prognosis of teeth
• relevant radiographs

Preventive and Interceptive Orthodontics

Loss of primary canine

• matter of great concern
• maxillary, if primary canine removed before CI and lateral incisors have moved together, likely to lead to incisor spacing and labioversion of the permanent canine
• mandible, may lead to lingual tipping of four mandibular incisors and blocking out of permanent canine

Loss of first primary molars

• if lost prior to eruption of 6s, would lead to mesial shift of E
• less likelihood of space loss if 6s are in occlusion
• little chance of loss of arch perimeter if lost during eruption of the 4

loss of secondary primary molar

• more damaging than loss of the D
• 6s drift forward immediately
• greatest loss when D lost prior to 6 eruption

Ankylosis

Ankylosis

• deciduous molars 1-9%
• ankylosis - fusion between cementum and dentine of tooth and bone of alveolar process
• mandibular first primary molar most common
• unclear aetiology
• wait for eruption of 1st permanent molars before surgical exo
• if there is evidence of root resorption, no indication for early removal
• surgical exo only if preventing eruption of succedaneous tooth
• space maintainer if early exfoliation

Appliance treatment in mixed dentition

removable

• adams cribs
• two z springs
• anterior cross bite
• pseudo class III
  • inclined plane
• tongue blade
  • one permanent incisor in cross btie without excessive overtbite
  • can use tongue blade or paddle pop stick to lever against it
  • put paddle pop stick lingual to it and bite against it while holding the other end of the paddle pop stick, use for 1 minute 6 times per day, interval of atleast half an hour
  • correction usually complete within a few days
• posterior cross bite
  • maxilalry appliance with a mid palatal expansion screw
  • quad helix
  • RME

Anomalies of eruption

Ectopic eruption of first permanent molars

• usually due to inadequate arch laength
• take radio to confirm presence of premolar
• more common in maxilla
• space regaining appliance to upright maxillary 6s to regain space,

Ectopic eruption of permanent canine

• majority in palatal
• 2% in maxilla
• investigate if not palpable at age 9-10

Parallax technique

• slob rule

Supernumerary teeth

• if obstructing eruption path of adjacent tooth, or has associated pathology, should be removed as soon as convenient
• risk vs benefit