What is orthodontics?

Dento-maxillary anomalies involve more than just uneven teeth; they most often represent combinations of the following disorders:

  • disorders of the mutual positioning and sizes of the upper and lower jaws (skeletal anomalies);
  • disorders of the shape of dental arches, uneven tooth position in the row (anomalies of tooth position);
  • disorders of tongue and lip function, incorrect swallowing, mouth breathing, harmful habits – thumb sucking, etc., which are often the cause of dento-maxillary anomalies and are a factor of instability in orthodontic treatment (functional disorders).

Thus, the goals of orthodontic treatment at the current stage of scientific development are:

  • harmonious development of the facial skeleton, facial aesthetics;
  • even tooth position in the dental arches, correct occlusion, smile aesthetics;
  • correct function (breathing, tongue, lips, cheeks, absence of harmful habits).

Orthodontic tooth movement

There are several main types of tooth movement in orthodontics:

  • Rotation – turning the tooth around a special point called the Center of resistance.
  • Translation – bodily movement of the tooth.
  • Intrusion – “sinking” the tooth into the bone, into the gum.
  • Extrusion – “pulling” the tooth out of the bone.
  • Tipping – tooth movement that combines rotation and bodily movement of the tooth.

Orthodontic tooth movement (details)

Orthodontic tooth movement refers to the slow movement of teeth to the desired position (for functional-aesthetic reasons) under the action of small forces (up to a few grams). From a mathematical point of view, orthodontic tooth movement resembles the movement of a solid body in a viscous medium.

Tooth movement occurs due to bone tissue resorption on one side and, conversely, bone tissue formation to fill the resulting free space on the other side. Large forces applied to the teeth can lead to acute inflammation and damage to the integrity of the dentoalveolar structures (tissues surrounding the tooth).

The theory of light forces in orthodontics

In modern orthodontics, it has been established that the lighter the forces applied to the teeth by the bracket system, the faster the teeth move. This is paradoxical, but a fact. Apparently, this is explained by the peculiarity of bone tissue and dentoalveolar structure resorption and regeneration processes.

Tooth movement with a bracket system

Brackets are small locks that are glued to the teeth on the vestibular or inner side. They have slots into which the archwire is placed and fixed. Through the brackets, the archwire exerts individual pressure on each tooth.

Modern bracket systems, in combination with rectangular archwires, allow pressure to be applied to the teeth not only inwards or outwards but also to cause rotation, tipping, or bodily movement of the teeth.