Orthodontic anchorage: definition, types and advantages

Orthodontic anchorage


What is an anchorage in orthodontics?

Anchorage in orthodontics means to prevent ‘an unwanted tooth movement.’ Anchorage is the resistance to the force that is not wanted to minimize the side effects on other teeth while aligning tooth or teeth in orthodontic treatment.

Do you remember Newton’s third law? It says that for every action or force, there will be an opposite reaction. Ok, this is exactly what you see that happens to teeth. When orthodontists want to move or align protruding teeth or fix jaw irregularities, they use anchorage techniques to stop that reaction or opposite force that happens in the other teeth. To have stable and firm braces or other orthodontic appliances in your mouth, the anchorage is necessary. Depending on the type of treatment and force or pressure in an area of teeth or jaw, orthodontists plan an appropriate anchorage system.

Orthodontic anchorage can take many shapes and forms:

  • TADs
  • Molar teeth
  • Dental implants
  • Bridges
  • Headgear (extraoral anchorage)
  • Transpalatal arch
  • Interach elastics
  • Spring designs in braces
  • Loop design in braces

What are the types of anchorage in orthodontics?

Orthodontists need a stable and not fragile anchor to do the orthodontic treatment without any damages to other oral structures like teeth and gums. So, they try to use the most suitable anchorage type in or outside of your mouth.

Three types of anchorage in orthodontics are:

  • Extraoral anchorage:

extraoral anchorage is the type of anchorage that is fixed outside the mouth to hold the force of tooth movement of our orthodontic treatment. Orthodontists use external skeletal parts of the body like the chin, neck, and head to fix the orthodontic appliance for aligning our jaw or teeth irregularities.

Headgear appliance in orthodontics is an exraoral anchorage appliance. Orthodontic headgears treat many jaw and teeth irregularities. By wearing headgear, based on different designs, the forces and pressure are spread well over the other skeletal parts of your body (head, neck, or chin). So, there will not be any side effects of moving the protruding jaw or teeth during your treatment.

  • Temporary anchorage devices (TADs) and osseo-integrated implants:

In this type of anchorage, orthodontists use bone in your oral structures to anchor your orthodontic appliance. Osseo-integrated implants and TADs are also called skeletal or bone anchorage. Orthodontists fix the anchors in the bone, which provides a stable and tough anchorage for your treatment. The bone density and maturation is a key factor for implanting skeletal anchorage. This is why skeletal anchorage of TADs is not recommended for children below 12 years old. You should have a good quality of bone to have TADs implanted.

  • Dental anchorage:

Teeth can be good anchorage when dentists or orthodontists make the most of them. Orthodontists and dentists can use as many teeth into the anchorage to stable the orthodontic braces or other appliances in the mouth. Teeth can distribute the force that is necessary to pull or push other teeth into the normal and fitted position. The best anchorage teeth are molar teeth (back teeth) and canine teeth because of the stable location or powerful root structures of these teeth.

orthodontics anchorage

What are temporary anchorage devices (TADs)?

Temporary anchorage devices or TADs are anchorage tools that are mechanically fixed into the bone in the mouth to act as anchors for your orthodontic appliance. TADs can be removed when your orthodontic treatment is over or when it is not necessary anymore.

TADs are screw-like devices that are implanted in the skeletal areas of oral cavity. The TADs anchorage has changed orthodontic treatment in a dramatic way. Before these devices, most orthodontic treatments required surgical procedures for treating complex irregularities in teeth. You had no choice to do surgeries if you wanted to complete your orthodontic treatment when irregularities in your teeth were severe.

The areas that TADs are placed should have bone density and bone maturation is needed. For orthodontic treatment of children, orthodontists wait for the appropriate age of the child when they get to the 12 years of age or till their puberty periods of children. Then, the implant TADs into the bony area. Alveolar bone, the rooftop of the mouth (palatal bone), lower and upper jaw bones and zygomatic arch in the jaw are the skeletal structures for the implanting TADs anchorage in orthodontics.

What are types of TADs?

In orthodontics today, different TADs are available to meet the needs of the amount of force and treatment time in each orthodontic treatment. Your orthodontic braces are attached to these TADs with coil springs or elastics to stay in place. Unless your orthodontist has used other anchorage ways, you can look at the TADs and the locations of these anchorage devices that are inserted in your bones in the mouth.

Main types of TADs are:

  • Miniscrews: miniscrews are made of titanium and are popular TADs in orthodontic anchorage. The designs of miniscrews allow the steel wires, elastics or springs to pass through them and hold your braces or other orthodontic appliance to firm and stable in your mouth. Miniscrews are easy to use for orthodontist and dentists and are mechanically applied with numbing the bone area first to prevent any pain. It doesn’t hurt and you don’t need to worry about the pain.
  • Miniplates: miniplates are TADs anchorage tools that consist of screws and plate. The plate should be contoured to fit the bone area. Miniplate application needs a little surgery but it can easily be done under local anesthesia. Orthodontists use this amazing temporary anchorage device to do complex teeth movement in orthodontics. Miniplates have multiple screws that can withstand against pressures and forces. Miniplates offer better orthodontic control and will not loosen during your treatment.

What are the advantages of TADs?

  • TADs offer highly stable anchorage in your orthodontic treatment
  • They fix your braces firmly in place
  • There will not be any unwanted movement of your braces or other orthodontic appliances
  • No surgeries is necessary to correct your teeth irregularities
  • It’s an alternative to  headgear if you are not interested in wearing headgear for your orthodontic treatment
  • TADs have made orthodontic time shorter
  • TADs are effective compared with other conventional anchorage systems
  • TADs are easy to apply
  • No damage to other teeth while pulling or pushing the others

Important tips on anchorage in orthodontics:

Finally, it is a good idea to follow these tips to have much stable anchorage for your orthodontic treatment

  • Do oral hygiene practices regularly
  • Use soft toothbrushes to brush your teeth or clean the area around miniscrews and other anchorage tools
  • Prevent plaque accumulation around the TADs
  • In case of any anchorage breakage or loss, visit your orthodontist immediately
  • If you develop any sensitivity or irritation around the TADs, report that to your orthodontist

Source: muih.edu