27. Classification of orthodontic appliances- concepts and principles of action

Question 1

How orthodontic appliances generally classified

Answer 1

• Clinical implication
• Position in oral cavity
• Location of anchorage
• Fixation of appliance

Question 2

Subcategories under clinical implication for orthodontic appliances

Answer 2

1. Therapeutic Appliances=>
   * Mechanical=>exert mechanical forces
   * Functional=>redistribute muscle force action and modify growth
   * Combined=>exert mechanical and functional forces
2. Interceptive Appliances=>
   * Passive=>barrier to prevent recurrence of oral habits
   * Active=>use dominant reflex to suppress oral habits
   * Space Maintainers=>preserve space in event of premature loss of primary teeth
3. Retentional Appliances=>
   * Permanent=>long-term wear
   * Temporary=>short-term wear

Question 3

How orthodontic appliances classified based on their position in oral cavity

Answer 3

• Unimaxillary Appliances=>act in single jaw either maxillary or mandibular
• Bimaxillary Appliances=>act simultaneously on maxilla and mandible
• Includes majority of functional appliances
• Unimaxillary w/ Bimaxillary Action=>positioned in one jaw but correct occlusal relationships in both jaws
• Appliances in Oral Vestibule=>Positioned in vestibular area of mouth

Question 4

Classifications of orthodontic appliances based on location of anchorage

Answer 4

1. Intraoral Anchorage=>
   * Apply mechanical forces directly to teeth using active force of orthodontic archwires
2. Extraoral Anchorage=>
   * Located outside patient’s mouth=>
   * Mechanical orthodontic appliances that apply orthopedic forces on teeth, dental arches, and jaws

Question 5

How orthodontic appliances classified based on their fixation

Answer 5

* Removable Appliances
* Attached=>have retention elements but can be removed by patient
* Unattached=>do not have retention elements and majority of functional appliances
* Fixed Appliances=>
* Bonded to teeth and cannot be removed by patient=>
* Multibracket systems, bonded retainers, rapid palatal expanders (RPE)