Malocclusions

Malocclusion refers to any deviation from normal alignment of teeth or harmonious relationship between the upper and lower dental arches resulting in abnormal occlusion that may be:

• Functionally harmful

• Periodontally damaging

• Associated with speech or mastication problems

• Aesthetically unacceptable

Normal occlusion allows efficient chewing, proper speech articulation, balanced facial growth, and temporomandibular joint stability.

Malocclusion is among the most common oral health problems worldwide after dental caries and periodontal disease.

Common contributing factors include:

• Genetic inheritance

• Abnormal jaw growth

• Early loss of primary teeth

• Oral habits

• Trauma

• Developmental disturbances

Pathophysiology

Malocclusion develops due to disturbance in the coordinated growth of:

• Teeth

• Alveolar bone

• Maxilla

• Mandible

• Orofacial muscles

Mechanisms involved

1. Skeletal discrepanciesMismatch between maxillary and mandibular growth leads to sagittal, vertical, or transverse disharmony.

2. Dental factors

3. Tooth size–arch length discrepancy

4. Ectopic eruption

5. Supernumerary teeth

6. Congenitally missing teeth

7. Functional influencesAbnormal muscle forces from habits such as:

8. Thumb sucking

9. Tongue thrusting

10. Mouth breathing

These forces alter eruption pathways and jaw development.

• Environmental causes

• Premature extraction of deciduous teeth

• Untreated caries

• Trauma affecting developing dentition

Classification (Diagnostic Criteria)

Class I Malocclusion (Neutroclusion)

• Normal molar relationship

• Anterior buccal groove of mandibular first molar aligns with mesiobuccal cusp of maxillary first molar

• Malalignment occurs due to:

  • Crowding

  • Spacing

  • Rotation

  • Crossbite

Most common form.

Class II Malocclusion (Distocclusion)

• Mandibular arch positioned at least half cusp width distal to maxillary arch

• Often associated with increased overjet

Subdivisions:

• Division 1: Proclined upper incisors

• Division 2: Retroclined upper incisors

Clinical effects:

• Lip incompetence

• Increased trauma risk

• Convex facial profile

Class III Malocclusion (Mesiocclusion)

• Mandibular arch positioned mesially relative to maxilla

• Reverse overjet common

Associated with:

• Prominent mandible

• Midface deficiency

• Concave facial profile

Signs and Symptoms

• Crowded or irregular teeth

• Spacing between teeth

• Protruding or retruded jaws

• Difficulty chewing

• Speech problems

• Mouth breathing

• Frequent cheek or tongue biting

• Temporomandibular joint discomfort

• Facial asymmetry

• Poor dental aesthetics

• Psychological distress or reduced self-esteem

Clinical Examination

Assessment includes:

• Facial profile analysis

• Jaw relationship evaluation

• Dental midline alignment

• Overjet measurement

• Overbite measurement

• Crossbite detection

• Open bite evaluation

• Arch symmetry

• Oral habits assessment

Investigation

Radiographic and diagnostic investigations include:

• Orthopantomogram (OPG)

  • Tooth presence

  • Impacted teeth

  • Developmental anomalies

• Lateral cephalometric radiograph

  • Skeletal relationships

  • Growth pattern analysis

• Study models or digital scans

  • Arch length discrepancy

  • Space analysis

• Photographic records

  • Treatment planning and monitoring

Treatment

Management depends on:

• Age of patient

• Growth potential

• Severity of malocclusion

• Skeletal versus dental origin

Non-pharmacological Management

Objectives include:

• Reduce temporomandibular joint dysfunction risk

• Prevent traumatic dental injuries

• Improve mastication and speech

• Reduce periodontal disease and caries risk

• Improve psychosocial wellbeing

Preventive Orthodontics

• Maintenance of primary teeth

• Space maintainers after early tooth loss

• Habit breaking appliances

• Serial extraction when indicated

Interceptive Orthodontics

Performed during mixed dentition stage.

Includes:

• Correction of crossbite

• Guidance of erupting teeth

• Expansion appliances

• Functional jaw modification

Removable Orthodontic Appliances

Useful in mild to moderate malocclusion:

• Retainers

• Expansion plates

• Space maintainers

• Functional appliances

Suitable for local primary care settings.

Fixed Orthodontic Appliances (Braces)

Indicated for:

• Moderate to severe malocclusion

• Relapse after removable appliance therapy

• Complex tooth movement

Patients should be referred to an orthodontist or oral and maxillofacial specialist.

Orthognathic Surgery

Required in severe skeletal discrepancies after growth completion.

Pharmacological Management

Pharmacological therapy is supportive only.

Indications include:

Pain after appliance placement:

• Paracetamol 500–1000 mg PO 8 hourly

Or

• Ibuprofen 400 mg PO 8 hourly

Management of appliance-related ulceration:

• Chlorhexidine mouthwash 0.2% twice daily

• Topical oral protective gels

Antibiotics are not routinely indicated unless infection occurs.

(According to Tanzania STG recommendations)

Complications of Untreated Malocclusion

• Dental caries

• Periodontal disease

• Tooth wear

• TMJ disorders

• Speech impairment

• Increased trauma risk

• Facial growth abnormalities

• Psychosocial impact

Prevention

Primary prevention:

• Early dental visits from age 6 years

• Prevention of premature tooth loss

• Caries control programs

• Elimination of harmful oral habits

Secondary prevention:

• School dental screening programs

• Early orthodontic referral

• Monitoring eruption patterns

Community prevention:

• Oral health education

• Access to preventive dental services

Patient Education

Patients and caregivers should understand:

• Early treatment reduces complexity and cost

• Good oral hygiene is essential during orthodontic therapy

• Regular follow-up is mandatory

• Appliance compliance determines treatment success

• Protective mouthguards reduce trauma risk

Prognosis

Excellent when:

• Diagnosed early

• Growth modification initiated during adolescence

• Patient compliance maintained

• Proper retention phase completed