The GDP's role in Orthodontics 

• The GDP is the primary clinician to notice when something may be abnormal in the developing occlusion and refer to an orthodontist.  
• This is why you need to know your eruption dates.

• It is paramount for the GDP to ensure the pt has optimal oral hygiene before referring to the orthodontist.  
  • Not only is this motivation for the patient, but realistically, the orthodontist will refuse treatment or halt treatment if oral hygiene standards are low. 
  • This is due to the exceptional plaque-retentive ability of braces, leading to increased risk of enamel decalcification and gingivitis. 
• Therefore, GDPs are responsible for carrying out their dental recalls on orthodontic patients.  
  • This is because orthodontists purely work on the braces. GDPs must review the rest of the patient's oral health and review and reinforce the maintenance of the braces.  
  • The GDP will also be responsible for helping with and reviewing the patient in soft tissue injury due to braces. For example, many people are given wax to apply over sharp areas of braces (eg. Wires) to prevent injury. 
  • This may mean reducing the recall for patients with orthodontic appliances. 
• The GDP will also be instructed by the orthodontist to extract any teeth required for treatment, so good communication is key! 

Evaluation of the Developing Occlusion 

Recognising abnormalities 

• The common things to look for in a patient in the mixed dentition: 
  • Extra teeth 
  • Missing teeth 
    • Commonly missing teeth 
      • 8s > L5 > U2 > U5 > L1 (1)
  • Delayed eruption – usually anything longer than 6 months from when the tooth on the contra-lateral side of the arch erupted.  
  • Asymmetry in eruption pattern – ask yourself, could a permanent successor be missing/impacted? 
  • Abnormal sequence of eruption – are teeth erupting in an odd order? 
  • Retained deciduous teeth – could it be ankylosed? Is there a permanent successor? 
  • Submerging deciduous teeth - could it be ankylosed? Is there a permanent successor? 
• The transition of occlusion in mixed dentition is ideally, ½ Class II molar relationship (in primary dentition, as Ds and Es meet 'cusp to cusp') to a Class 1 molar relationship (in permanent dentition). 

Interceptive Orthodontics- It's all about the timing! 

Spotting the Problems: 

• Eruption: impacted/ ectopic 
• Crossbites 
• Poor Quality First Permanent Molars (MIH/ Caries) 
• Infra-occluded primary molars 
• Habits: Anterior open Bites, Posterior crossbites, Overjet increase 
• Centre Line Shifts 
• Overjet and Trauma risk  

Impacted Maxillary Permanent Central Incisors:  

• Eruption usually around 6/7yrs of age 
• Can present as a midline diastema. 
• Delay of abnormal pattern should be investigated – Take RADs 
• Ensure to maintain the space once the A is lost, to allow room for the U1 to come through.  
• Non-eruption causes: 
  1. Trauma 
     1. Ankylosis of A/ hypoplasia to the U1/ may cause damage to the U1/ form an odontome in a reactionary process 
     2. Dilaceration (crown or root) = difference in angulation in the tooth.  
  2. Supernumerary – extra tooth, can be erupted or unerupted.  
     1. Mesiodens- conical.  
     2. Tuberculate – malformed premolars  
     3. Supplemental – extra teeth of normal morphology. These typicallly erupt in the correct position for the permanent dentition.  
• Refer to RCS Guidelines for treatment (2)

Palatally Ectopic Canines: 

• Aetiology: Small Laterals (small roots) or missing laterals.  
• Class II Div II typically 
• If left, can start causing root resorption of teeth involved in impaction.  
• Usually erupt around 11/12 years and are palpable buccally at 9-10 years. Make sure you check for this! 
  • If you cannot feel them, it is sensible to take a RAD.  
• Use the SLOB rule to determine the canine's location: See 'what the patient should expect at the orthodontist ' page.
• They are typically exposed using a palatal 5-5 flap.
• Recommended Treatment:  
  • Consider space creation: Extraction of Cs or arch expansion (or combination)  
  • If extracting C's, then space-maintainers may be necessary to ensure the space does not close and impede the eruption of the canine.  
  • Follow RCS Guidelines. (3)

Anterior Crossbites: 

• Best to correct in mixed dentition.  
• Left untreated could lead to attrition of the labial surfaces of upper incisors, fractured lowers, increased mobility and gingival recession.  
• Recommended Treatment: 
  1. Temporary crown/ composite build ups 
  2. Fixed appliances:  corrects the crossbite in 6 weeks – 3 months 

Posterior Crossbites: 

• Premolar to molar region. Aetiology is normally a narrow upper arch.  
• Correction is not always essential – treatment decision should be based on functional need.  
• Purpose of treatment is usually to expand the maxilla and eliminate any mandibular displacement.  
• Treatment:  
  • Removable appliance 
  • Better OHI and similar long-term stability regardless of speed of correction shown by the Quadhelix.  

Poor Prognosis 6s: 

• Susceptibility to caries and effects of MIH (post-eruptive breakdown). 
• IDEAL XLA timing: allows the 7 to drift and erupt mesially providing acceptable occlusion 
  • When bifurcation of 7s is visible on radiographs – between 8.5-10 years 
  • Too early = distal tipping of L5 
  • Too late = not enough meisal movement of L7, gap not filled.  
• Try and keep L6s where possible – these are more crucial.  
• Upper 7s mesial movement is more predictable and favourable.  
• Treatment: Follow current RCSEng Guidelines. (4) 
  • Follow this until more evidence is provided. 
  • Lower 6s are more crucial compared to Upper. 
  • Compensate the Upper when XLA the Lower but not so crucial the other way around.  
• *Balancing extraction = preserves symmetry and prevents centre-line shift- involves extracting the contra-lateral tooth in the same arch.  
• *Compensating extraction = allows molar teeth to drift in unison and prevent over-eruption. Involves removing the ipsi-lateral opposing tooth.  

Infra-occluded Es: 

• Strong genetic components 
• Below the occlusal plane  
• Early marker for Dental Abnormalities. E.g. Ectopic canines, Hypodontia (tooth agenesis) 
• Typically due to ankylosis of roots.  
• Aplastic successor: slow root resorption leading to lack of exfoliation especially 12-13yrs  
• Treatment: 
  • Ideally we should wait for exfoliation. 
    • Timing of exfoliation on the other side of the arch to give a guide.  
  • XLA ONLY:  
    • deep infraocclusion – tilting/ tipping the adjacent teeth and space loss. 
    • No permanent successor and concerns for future treatment of infra-occlusion. Refer to orthodontist for advice. 
• Grading of infra-occlusion: 
  • Slight: occlusal surface approx. 1mm below occlusal plane 
  • Moderate: occlusal plane approx. At the level of the contact points of the adjacent teeth 
  • Severe: occlusal plane below the contact points, potentially at gingival level and allowing tipping of the adjacent teeth. 

 Centre-Line Shift: Unilateral loss of primary teeth 

• 2mm or more is noticeable 
• Difficult to correct in permanent dentition 
• Can typically involve a C/D/E  
•  Recommendation:  
  • Balanced XLA if one primary canine (C) has exfoliated early and the contralateral is firm then do the XLA. 

Increased Overjet: 

• Increased overjet increase the risk of trauma to the teeth – twice as likely to have a dental injury. 
• 6yrs is the most common age for dental trauma and then again between 8-10yrs 
• With a lack of lip coverage this increases severity likelihood if injury occurs.  
• Intervene if child is being bullied  
• Treatment: 
  • Twin block  
  • Mouthguard fabrication 

Summary: