Can Changing the Transverse Dimension Improve the Quality of Orthodontic Treatment in Children? Dr. Roberta Lione
Malocclusion is not a disease, but rather a set of dental deviations which in some cases can influence quality of life
· Quality of life
o RME can improve the QOL McNamara 2015
Presentation of narrow maxilla:
· Facial presentation
o Underdeveloped midface
o Narrow pharangeal airway
o Increased nasal resistance
o Mouth breathing
o Altered tongue position
AOB presentation
· Maxillary narrow in AOB cases compared to normal growing patients
o Mechanical blockage of the incisors and anterior maxilla
o Poor upper tooth to lip
o Reduced gingival show on smiling
· Palatal morphology of AOB Vs control Lagena 2018
o Difference in AP and vertical morphology of palate
o AOB palates higher and narrower than control
o AOB cases narrow maxilla and mandible Balanti 2009
o Narrow nose, narrow alar base, narrow zygomatic and mandible
· Functional imbalance
o Excessive vertical growth in the maxilla
o Clockwise rotation of growth
Treatment modalities
1. Orthodontic therapy – dentoalveolar openbites
a. Quadhelix with spurs – eliminate digit sucking habit. Jones 1989, Henry 1993
2. Orthopaedic approach
a. RME – skeletal origin of AOB (hyperdivergent cases)
b. Lower removable bite blocks
i. 5mm lower bite block
RME and lower removable bite block treatment for AOB
· Expansion allows spontaneous eruption of the upper incisors (narrow arch resulting in mechanical obstruction in vertical eruption)
· Expansion can increase the vertical dimension, to control the vertical dimension bite blocks in the lower arch can be used
Evidence Lione 2017 AJODO
1 year of RME and bite block
· Significant rotation of mandibular rotation
· Improve AOB by 2mm
· LAFH decrease by 1.5mm
Stability long term Mucedero 2018
· Maintained reduced extrusion of molars, when compared to untreated AOB cases
· Overbite 1.8mm greater in treated group Vs control
Effects of RME on facial pattern in AOB cases Lione 2019
· Changes of patients cephalogram analysis
· Effect of RME
o Increase in ramu height / posterior face height
o Counter clockwise rotation of the mandible
o Reduced steepness of occlusal plane