Defining the boundary between functional necessity and cosmetic desire — and establishing precise treatment targets for medically guided and orofacial guided orthodontic care.
PART A — DEFINITION & CRITERIAPART B — TREATMENT TARGETSMEDICALLY GUIDED ORTHODONTICSOROFACIAL GUIDED ORTHODONTICSKEY REF: SEMINAR SEP 2016
A
PART A
Define Medically Necessary Orthodontics
DEFINITION
Medically necessary orthodontics refers to orthodontic treatment required not primarily for aesthetic improvement, but to correct or prevent a condition with a demonstrable, clinically significant impact on a patient's physical health, function, or quality of life — and where orthodontic intervention is an essential, integral component of the medical or surgical management plan.
This distinction carries profound implications for insurance coverage, resource allocation, and treatment prioritisation in public health systems. The referenced article highlights that while the concept is widely accepted, its application remains one of the most contested areas in modern orthodontic practice.
Key Criteria That Define Medical Necessity
Functional impairment is present or anticipated
The condition causes or is likely to cause a clinically measurable functional problem — mastication, swallowing, speech, breathing, pain, or nutritional compromise.
Orthodontic treatment is integral to the medical/surgical plan
Not an add-on or cosmetic adjunct — the overall medical outcome would be significantly compromised without orthodontic intervention.
The condition is not primarily cosmetic
While aesthetics may improve as a secondary benefit, the primary driver is health, function, or structural integrity — not appearance.
Evidence-based justification exists
Supported by clinical findings, diagnostic records (radiographs, models, photographs), and specialist opinion from other disciplines where applicable.
Orthodontics is the most appropriate intervention
The indicated treatment of choice — not merely one of several optional interventions of comparable value.
Challenges in Defining Medical Necessity
The referenced article specifically highlights the considerable challenges in applying this concept in practice:
CHALLENGE 01
SUBJECTIVITY OF THE BOUNDARY
The line between "medically necessary" and "cosmetically desirable" is not always clear-cut. A severe Class II may cause functional limitation, psychosocial distress, and trauma risk — but quantifying these objectively for insurance purposes is difficult.
CHALLENGE 02
LACK OF UNIVERSAL INDICES
Various indices exist (HLD, IOTN, DAI, PAR) but none is universally accepted as the definitive threshold for medical necessity across all health systems and jurisdictions.
CHALLENGE 03
SYSTEM-SPECIFIC DEFINITIONS
What qualifies varies between countries, insurance providers, and public health systems. NHS, Medicaid, and CPSP-affiliated systems each apply different thresholds and criteria.
CHALLENGE 04
PSYCHOSOCIAL DIMENSIONS
Severe malocclusion can cause significant psychological harm (bullying, social exclusion, self-esteem). Psychosocial need is rarely formally recognised as a standalone basis in most systems.
Clinical Examples of Medically Necessary Conditions
CONDITION
MEDICAL NECESSITY JUSTIFICATION
Cleft lip and palate
Pre- and post-surgical orthodontics essential for surgical closure, speech, feeding, and bone graft site preparation
Severe skeletal Class II or III
Orthodontic decompensation required before orthognathic surgery for functional jaw correction
Obstructive sleep apnoea (OSA)
Mandibular advancement or arch expansion to improve airway patency — clinically proven functional benefit
Craniofacial syndromes
Orthodontics integral to multidisciplinary craniofacial surgical management (Crouzon, Apert, Treacher Collins)
Traumatic dental injury
Space management and alignment required for implant or fixed restoration placement — preserves function
TMJ ankylosis
Post-surgical orthodontics after joint reconstruction essential for functional occlusal rehabilitation
Ectodermal dysplasia
Space management and prosthodontic preparation — orthodontics integral to full rehabilitative plan
Severe anterior open bite
Functional compromise to swallowing pattern and sibilant phonemes constitutes medical justification
Impacted teeth with pathology
Orthodontic traction required as part of management of dentigerous cyst, root resorption, or eruption failure
· · · ·
B
PART B — FRAMEWORK 1
Treatment Targets: Medically Guided Orthodontics
FRAMEWORK OVERVIEW
Medically guided orthodontics is driven by systemic health, surgical outcomes, and functional rehabilitation. Treatment targets are structural — focused on teeth, bones, and jaws as components of a larger medical management plan.
T1
Restore and Optimise Masticatory Function
Achieve stable, functional occlusion with adequate posterior support allowing normal chewing efficiency and swallowing. Establish bilateral simultaneous posterior occlusal contacts to reduce asymmetric TMJ loading. Correct posterior crossbites causing lateral mandibular displacement. Eliminate premature contacts driving the mandible into dysfunctional positions.
T2
Eliminate or Prevent Pain
Address dentally or skeletally-mediated orofacial pain. Correct malocclusions perpetuating or creating TMJ dysfunction — disc displacement, condylar overloading. In progressive condylar resorption: establish occlusion minimising condylar compressive loading. Reduce myofascial pain from chronic postural compensation for malocclusion.
T3
Prepare for Surgical Correction — Pre-surgical Orthodontics
Dental decompensation — remove compensations masking the skeletal discrepancy. Establish arch coordination — upper and lower arches coordinated in width and form to fit after surgical repositioning. Create surgical wafer compatibility. Correct dental midlines relative to jaw bases. Level arches to allow correct vertical jaw positioning post-surgery. Duration: 12–18 months conventionally, or abbreviated in Surgery First Approach.
T4
Protect and Restore Airway
In OSA patients: upper arch expansion (RME or SARME) to reduce nasal resistance. Mandibular advancement to increase retrolingual and retropalatal airway dimensions. Correction of severe overjet and retrognathia demonstrated to improve airway patency. Integration with CPAP therapy or MMA surgery where orthodontics alone is insufficient.
T5
Enable Prosthetic and Implant Rehabilitation
Create correct space, alignment, and root parallelism for implant placement following tooth loss. Open or maintain space at sites of congenitally absent or lost teeth. Correct axial inclinations of adjacent teeth for perpendicular implant placement. In ectodermal dysplasia and oligodontia: entire orthodontic treatment planned around prosthetic end result — orthodontics as a preparatory service for comprehensive rehabilitation.
T6
Support Cleft Management
Pre-surgical infant orthopaedics(NAM — nasoalveolar moulding) in neonatal period to mould alveolar segments. Pre-graft alignment — open space at cleft site for alveolar bone grafting (age 9–11, before canine eruption). Maintain space for bone graft and subsequent tooth eruption or implant. Post-graft orthodontics — guide canine through grafted bone, close residual spaces, coordinate arches for Le Fort I.
T7
Normalise Skeletal Growth in Growing Patients
Use functional appliances, orthopaedic forces, or facemasks to redirect abnormal jaw growth. Modify condylar growth in Class II — Twin Block, Herbst, Forsus. Restrain or redirect in Class III— reverse pull headgear, chin cup. In craniofacial syndromes: coordinate orthodontic timing with surgical distraction osteogenesis and craniofacial procedures.
· · · ·
B
PART B — FRAMEWORK 2
Treatment Targets: Orofacial Guided Orthodontics
FRAMEWORK OVERVIEW
Orofacial guided orthodontics treats the orofacial system as an integrated functional unit — recognising that dental arches exist within a dynamic environment of muscles, airways, joints, and neuromuscular patterns. Targets extend beyond teeth and bones to the entire functional system.
T1
Optimise Orofacial Muscle Function and Balance
Achieve lip competence — upper and lower lips meeting at rest without strain. Incompetent lips indicate excess lower facial height or dental protrusion and perpetuate the malocclusion. Correct tongue posture — habitual low tongue posture fails to support the upper arch, contributing to transverse constriction and vertical malocclusion. Establish normal buccinator mechanism and reduce excessive mentalis activity.
T2
Correct Oral Habits as Treatment Goals
Thumb/digit sucking — active habit cessation is a treatment target, not a side note; the habit perpetuates anterior open bite and bimaxillary protrusion. Tongue thrust (atypical swallowing) — persistent infantile swallow pattern contributes to anterior open bite; orofacial guided orthodontics includes myofunctional therapy as part of the plan. Mouth breathing — perpetuates narrow upper arch, high palatal vault, and increased lower face height.
T3
Nasal Breathing Optimisation
Upper arch expansion (RME or SARME) to reduce nasal airway resistance — demonstrated to increase nasal airflow. Eliminate posterior crossbite contributing to nasal obstruction. Coordinate with ENT — adenoidectomy, turbinate reduction, septal surgery where structural nasal obstruction coexists. Target: habitual nasal breathing at rest — not oral breathing. Nasal breathing is critical for normal mid-face development; mouth breathing produces classic "adenoid facies."
T4
Myofunctional Coordination
Align dental arches to support proper muscle balance between tongue, lips, cheeks, and suprahyoid/infrahyoid musculature. Integrate orofacial myofunctional therapy (OMT) — exercises targeting lip seal, tongue posture, nasal breathing, and chewing patterns — as an adjunct to orthodontic treatment. Studies show OMT reduces relapse in open bite correction and improves long-term stability of arch expansion.
T5
Temporomandibular Joint Health
Establish an occlusion that does not create or perpetuate TMJ dysfunction. Avoid occlusal interferences causing lateral mandibular shifts or condylar deflection. In patients with diagnosed TMD: joint stabilisation first(splint therapy) before orthodontic mechanics are initiated. Monitor condylar position throughout treatment — avoid mechanics increasing condylar compressive loading in susceptible patients.
T6
Speech Function
Correct dental relationships impairing phonation: anterior open biteimpairs sibilant sounds (s, z, sh) producing a lisp; severe Class IIIaffects labio-dental (f, v) and inter-dental sounds; missing upper anteriors impacts multiple phonemes. Coordinate with speech-language pathologist (SLP) where articulation disorders coexist. Distinguish dental-structural speech problems (correctable by orthodontics) from motor-speech disorders (requiring SLP intervention).
T7
Swallowing Normalisation
Correct skeletal and dental architecture to support transition from infantile to mature swallowing pattern. In anterior open bite cases: merely closing the bite orthodontically without addressing tongue thrust leads to relapse. Orofacial guided target: achieve a mature swallowing pattern with posterior tongue seal, not anterior tongue thrust against incisors. Myofunctional therapy integrated with orthodontic treatment to achieve and maintain this.
· · · ·
Summary: Key Differences Between the Two Frameworks
Both frameworks share a common foundation: orthodontics is not practised in isolation. Whether the driver is a systemic condition requiring surgical correction or a neuromuscular dysfunction perpetuating a dental pattern — the orthodontist is one member of a larger team, and treatment targets must reflect the broader health and functional goals of the patient's entire management plan.
KEY REFERENCES
PRIMARY
Seminar September 2016: AJODO Seminar Series — Medically Necessary Orthodontics.
ARTICLE
"Medically necessary orthodontic care: Challenges and applications." American Journal of Orthodontics and Dentofacial Orthopedics.
Harvold EP — Orofacial function and form. | Hanson ML — Orofacial Myofunctional Therapy. | Graber LW, Vanarsdall RL, Vig KWL. Orthodontics: Current Principles and Techniques, 6th Ed.
