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Treatment decision in adult patients with Class III malocclusion: Orthodontic therapy or orthognathic surgery?

Anisha ValliLeave a comment

Class III malocclusion is one of those topics that every orthodontic student eventually dreads—complex etiology, unpredictable growth, and tough treatment calls, especially in adults.

But what if we told you that there is a systematic way to simplify treatment planning?

A classic study by Stellzig-Eisenhauer et al. gives us a powerful, evidence-based roadmap. This blog breaks it down into easy, clinic-ready points.

🔍 Why Class III in Adults Is So Challenging

  • Growth is almost complete → no skeletal correction with ortho alone.
  • Many patients show combined skeletal + dentoalveolar features.
  • Borderline cases make it hard to decide between:
    • ✔️ camouflage orthodontics (non-surgical)
    • ✔️ orthognathic surgery with orthodontics

The BIG Q: How do we objectively decide?

HIGH-YIELD CEPH PARAMETERS

A. Primary Predictor

Wits Appraisal (MOST RELIABLE)

  • −1 to −5 mm → Often orthodontic (camouflage)
  • < −7 mm → Borderline
  • ≤ −10 mm → Usually surgical

B. Other Key Predictors (Discriminant Model)

VariableTrendInterpretation
S–N Length↓ shorterIncreased likelihood of surgery
M/M Ratio (Maxilla/Mandible)↓ lowMandibular excess or maxillary deficiency → surgery
Lower Gonial Angle↑ largeVertical growth pattern → challenging to camouflage

3️⃣ NON-SURGICAL (ORTHODONTIC) CANDIDATES

Likely treatable with camouflage if:
✔ Wits > −6 mm
✔ Acceptable facial esthetics
✔ Mild–moderate skeletal discrepancy
✔ Good incisor inclinations possible (no excessive decomp needed)
✔ No significant vertical maxillary deficiency
✔ Patient prefers non-surgical path

Common Strategies:

  • Class III elastics
  • Lower incisor retraction (limits apply)
  • Upper expansion/advancement via dentoalveolar mechanics
  • Mini-screws for camouflage anchorage

4️⃣ SURGICAL CANDIDATES

Recommend ortho + orthognathic surgery when:
✔ Wits ≤ −8 to −10 mm
✔ Severe skeletal discrepancy (maxillary deficiency / mandibular prognathism)
✔ Large M/M discrepancy
✔ High lower gonial angle (vertical growers)
✔ Soft-tissue profile compromised
✔ Decompensation needed beyond safe limits
✔ Patient wants ideal esthetics & occlusion

Typical Surgical Options:

  • Le Fort I Maxillary Advancement
  • BSSO Mandibular Setback
  • Bimaxillary Surgery (common)

5️⃣ BORDERLINE CASE CHECKLIST

Use these for “grey-zone” decisions:

  • ☐ Dual bite? (Check CR vs CO)
  • ☐ Incisor decompensation possible without harming periodontium?
  • ☐ How much soft tissue improvement expected?
  • ☐ Stability concerns? (high angle, open bite tendency)
  • ☐ Patient esthetic expectations?
  • ☐ Realistic with camouflage forces?

If ≥ 3 boxes checked → lean toward surgery.

6️⃣ MANDATORY CLINICAL EXAM ELEMENTS

  • Check for functional shift
  • Evaluate soft-tissue profile (nasolabial angle, chin, lip support)
  • Assess transverse discrepancies
  • Evaluate vertical dimension
  • Understand patient desires (esthetic vs non-surgical preference)

7️⃣ RED FLAGS FOR CAMOUFLAGE

❌ Excessive lower incisor retroclination needed
❌ Gingival recession risk (thin biotype)
❌ Severe negative overjet > −6 mm
❌ Poor soft tissue esthetics (protrusive chin)
❌ Vertical dysplasia

8️⃣ RAPID SUMMARY

ORTHO ONLY = Mild skeletal discrepancy + Acceptable esthetics + Wits > −6 mm
SURGERY = Severe skeletal Class III + Esthetic disharmony + Wits < −10 mm
BORDERLINE = Depends on soft tissue, decomp needs, patient expectations

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