9.3 Paediatric Dentistry, Orthodontics & Oral Surgery Essentials

Paediatric Dentistry and Prevention Frameworks

Paediatric dental care in the UK centers on biological caries management and traumatic injury protocols.

Caries Prevention Guidelines (Delivering Better Oral Health)

The Department of Health & Social Care (DHSC) publication Delivering Better Oral Health: An Evidence-Based Toolkit for Prevention establishes mandatory UK prescribing standards:

Biological Caries Management and Operative Paediatric Dentistry

• The Hall Technique: A non-invasive technique for restoring carious primary molars by cementing preformed metal crowns (PMCs / Stainless Steel Crowns) over teeth using glass ionomer cement without local anaesthesia, caries removal, or tooth preparation. By sealing active caries from the oral environment, the biofilm is deprived of substrate and becomes dormant.
• Pulp Therapy in Primary Molars: Indicated when caries extends to the pulp:
  • Vital Pulpotomy: Indicated for reversible pulpitis. Amputation of coronal pulp followed by application of 15.5% Ferric Sulfate for 15 seconds (or MTA/Biodentine) to achieve haemostasis, capped with zinc oxide eugenol and a PMC.
  • Pulpectomy: Indicated for non-vital necrotic primary molars; canals are instrumented and obturated with a resorbable paste (Zinc Oxide Eugenol or Vitapex [iodoform + calcium hydroxide]).

Traumatic Dental Injury (TDI) Protocols (IADT Guidelines)

                        [Traumatic Avulsion Injury]
                                     │
          ┌──────────────────────────┴──────────────────────────┐
          ▼                                                     ▼
[Primary Tooth Avulsion]                              [Permanent Tooth Avulsion]
(DO NOT REPLANT: Risk of                              (Replant Immediately!)
 damaging permanent germ)                                       │
                                     ┌──────────────────────────┴──────────────────────────┐
                                     ▼                                                     ▼
                          [Extra-oral Dry Time <60 mins]                       [Extra-oral Dry Time >60 mins]
                          - Rinse gently with saline/HBSS                      - Non-viable PDL cells
                          - Replant & verify position                          - Replant to maintain bone
                          - Flexible splint for 2 WEEKS                        - Ankylosis / Resorption expected
                          - Closed apex: RCT at 7-10 days                      - Splint for 2 WEEKS

[!IMPORTANT] Optimal Storage Media for Avulsed Teeth: If immediate replantation at the accident site is impossible, store the tooth in Hank's Balanced Salt Solution (HBSS), cold milk, or saline. NEVER store an avulsed tooth in tap water (hypotonic environment causes rapid PDL cell lysis) or allow it to dry in tissue paper.

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Orthodontics Principles and Diagnosis

Orthodontic diagnosis requires systematic classification of malocclusion and objective assessment of treatment priority.

Index of Orthodontic Treatment Need (IOTN)

The UK NHS funds orthodontic care based on the IOTN, comprising two components:

1. Dental Health Component (DHC)

Evaluates anatomical severity on a 5-point scale (Grade 1 = No need, Grade 5 = Very great need). Priority is categorized using the MOCDO hierarchy (Missing teeth, Overjet, Crossbite, Displacement, Overbite):

• DHC Grade 5 (Mandatory NHS Eligibility):
  • 5i: Impeded eruption of teeth (excluding 3rd molars) due to crowding, displacement, or supernumerary teeth.
  • 5a: Increased overjet >9 mm.
  • 5m: Reverse overjet >3.5 mm with reported masticatory or speech difficulties.
  • 5p: Defects of cleft lip and palate.
• DHC Grade 4 (Great Need / NHS Eligible):
  • 4a: Increased overjet 6.1 mm to 9.0 mm with incompetent lips.
  • 4b: Reverse overjet 1.5 mm to 3.5 mm.
  • 4f: Increased complete overbite with gingival or palatal trauma.
  • 4d: Severe displacement of contact points >4.0 mm.
• DHC Grade 3 (Borderline Need): Overjet 3.5–6.0 mm; displacement 2.0–4.0 mm.

2. Aesthetic Component (AC)

Utilizes a 10-point scale of standardized photographs (Grades 1–4: No/little need; Grades 5–7: Borderline; Grades 8–10: Great need).

Cephalometric Analysis and Skeletal Relationships

Cephalometric tracings assess sagittal and vertical skeletal relationships:

• SNA Angle (Norm: 82° ± 2°): Relates the maxilla to the cranial base (Sella-Nasion).
• SNB Angle (Norm: 80° ± 2°): Relates the mandible to the cranial base.
• ANB Angle (SNA minus SNB; Norm: 2° to 4°): Defines sagittal skeletal pattern:
  • Class I Skeletal Pattern: ANB = 2° to 4°.
  • Class II Skeletal Pattern: ANB >4° (Maxillary prognathism or mandibular retrognathism).
  • Class III Skeletal Pattern: ANB <2° (Mandibular prognathism or maxillary retrognathism).

Biomechanics of Orthodontic Tooth Movement

Tooth movement occurs via remodeling of the periodontal ligament (PDL) and alveolar bone under sustained mechanical force:

• Compression (Pressure) Side: Sustained light force constricts microvasculature, leading to osteoclast differentiation and direct bone resorption.
• Tension Side: PDL fibers are stretched, stimulating osteoblast activity and bone apposition.
• Hyalinization: Heavy forces cause microvascular necrosis and sterile necrosis (hyalinization) of the PDL, resulting in delayed undermining resorption and root resorption risks.

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Oral Surgery and Local Anaesthesia Essentials

Safe surgical exodontia requires pharmacology mastery and strict compliance with national surgical guidelines.

Local Anaesthetic Pharmacology and Dosing Rules

Local anaesthetic agents block voltage-gated sodium channels along the neuronal membrane:

[!WARNING] Articaine Safety Considerations: Due to an increased reported incidence of prolonged paraesthesia, Articaine 4% is contraindicated for Inferior Alveolar Nerve Blocks (IANB) in UK dental practice, but is highly effective for buccal infiltration in both maxillary and mandibular dentitions.

Surgical Extraction and Flap Principles

• Elevator Mechanics: Elevators function via three mechanical principles: Leverage (first-class lever; fulcrum on alveolar bone), Wedge (two-inclined planes driven parallel to root space), and Wheel-and-Axle (rotation of handle turns blade, e.g., Cryer elevators).
• Flap Design Rules: Mucoperiosteal flaps must be full-thickness (incorporating mucosa and periosteum); possess a broad base to ensure adequate blood supply; have incision lines resting on sound, un-operated bone; and avoid damaging neurovascular bundles (e.g., mental nerve, lingual nerve).

National Guidelines and Surgical Complications

• NICE Guidelines on Third Molar Extraction: Prophylactic removal of pathology-free impacted third molars is strictly disadvised. Indications for surgical removal include: uncontrollable or recurrent pericoronitis (≥2 episodes), non-restorable caries, pulpal/periapical pathology, internal/external root resorption, or dentigerous cysts.
• Alveolar Osteitis (Dry Socket): Occurs due to premature plasmin-mediated fibrinolysis of the post-extraction blood clot. Presents with severe, throbbing pain 1 to 3 days post-extraction. Management involves gentle irrigation with warm sterile saline and packing with Alvogyl (an antiseptic, analgesic dressing containing eugenol, iodoform, and butyl paraminobenzoate).
• Medication-Related Osteonecrosis of the Jaw (MRONJ): Exposed bone in the maxillofacial region persisting >8 weeks in patients treated with antiresorptive drugs (Bisphosphonates e.g., Alendronic Acid, Zoledronic Acid; Denosumab) or anti-angiogenic agents. Dental extractions must be executed with minimal trauma, primary flap closure where possible, and strict avoidance of periosteal disruption.