Join me for a summary of Dr Bing Fang’s lecture entitled: Biomechanical Research and clinical application of orthopaedic Treatment on Adolescent mandibular retrognathia. It was part of the first International Orthodontic Foundation online symposium, with Ravi Nanda: https://www.iofglobal.org

Intrusion with aligners

Clinical risk of anterior intrusion, can cause retroclination / proclination.

• Plan with assessing lower incisor inclination relative to skeletal structure from a cephalogram
• To figure out this problem they designed a finite element study to figure out what happens for different lower incisor inclinations
• If the IMPA angle exceeded 100 the intrusive force will be in front of CR resulting in a moment causing lingual root torque and buccal crown torque
• If the IMPA angle less than 100 the intrusive force will be behind the CR resulting in a moment causing buccal root torque and lingual crown torque
• Plan intrusion:
  • Proclined teeth: intrusion and retraction at the same time with lingual crown torque
  • Retroclined teeth: Intrusion, with labial crown torque

Advanced Mandibular Spring AMS with aligner

• Telescopic arm with spring.
• Distalization of posterior and no movement in the anterior along with anterior bit turbos
• Class II elastics are used day time, appliance at night
• Inserts into connectors which are imbedded into the aligner
• How does it work
  • Finite model analysis, favourable for advancing the mandible – PDL even stress, promote mandibular growth, stress on condylar anterior aspect and posterior glenoid fossa

alignerorthodontics #class2 #Bingfang #farooqahmed