Normally, maxillary teeth vertically cover about 2 to 3 mm of the mandibular teeth. When this vertical overlap or contact between the teeth is lost, this is called an open bite. Orthodontists may employ different methods to treat this malocclusion, one of which is the use of lower anterior high pull headgear (LAHPH). It has been reported that LAHPH can effectively treat moderate open bites in adults.
Open bite: nature and causes
Open bite is a malocclusion caused by impaired jaw development, genetic factors, bad habits (e.g. finger sucking, nail-biting, lip and tongue sucking), and the improper eruption of anterior and maxillary teeth.
As we know, bad habits such as sucking on a pacifier and fingers are more common in girls than boys. Continuation of these bad habits can negatively affect both the soft and hard oral tissues. The severity of these consequences depends on how much and how long children have these habits.
An open bite occurs when these consequences result in the delayed eruption of some upper and lower front teeth. Orthodontists argue that open bites will improve if children break these habits at the right time before the eruption of permanent teeth.
How LAHPH works in the treatment of moderate open bite in adults?
Anterior open bite is one of the most controversial malocclusions among orthodontists. Since an open bite is associated with dental problems at lower ages, it may turn into a skeletal-dental complication as the patient grows older.
LAHPH has a very simple mechanism of action; when the patient wants to open their mouth, the extrusion force generated by the elastic tension is transmitted to the mandibular incisors, resulting in the closure of the open bite. Therefore, one of the therapeutic purposes of the high pull headgear is to apply intrusion force on the posterior part. In fact, the high pull headgear both serves as a support for the two hooks (which extrude the anterior teeth of the mandible) and intrudes the posterior teeth. An important point in this method is that the edge of the mandibular incisor should be lower than the lip line to allow the extrusion of mandibular teeth without adverse effects on the smile beauty.
LAHPH can be effectively used to correct moderate open bites in adult patients with a class-I malocclusion. Especially for those who are not willing to undergo orthognathic surgery.
Advantages of LAHPH in the treatment of open bite
The use of LAHPH in the treatment of open bite has some unique advantages over other methods. For instance, the use of LAHPH is preferred to vertical braces because it does not cause the gingival smile. Moreover, it can be placed on the anterior part of the maxilla with a mini screw to extrude the anterior teeth of the mandible using a brace.