Self correcting anomalies are termed as Transient malocclusion, these are not true malocclusion’s but mimic malocclusion during the normal development of dentition and occlusion. they do not need any corrective measures but get corrected themselves as they pass through the developmental stages .
Self correcting Anomalies are classified based on the stages of tooth development they are seen in.
- Gum Pads: Increased Overjet (Retrognathic mandible), Open Bite, Infantile Swallow
- Primary Dentition: Anterior Deep Bite, Flush Terminal plane, Primary Spacing
- Mixed Dentition: End on 1st Permanent Molar Relation, Ugly Duckling Stage, <2mm Mandibular lower incisors crowding.
- Permanent Dentition: Overjet and OverBite
Gum Pads Period:
Increased overjet is due to the increased growth of Maxilla compared to that of mandible. The Maxillary Gum pads are considerably placed ahead of the mandibular Gum Pads which last for 6 months after birth. It is also due to the Retrognathic state of the mandible when compared to that of the Maxilla in the Gum Pads stage.
As you can see in the above image the maxilla and mandible gum pads are not in relation to each other which means they are not in contact with each other. Hence the Gum pads when in contact with each other in the posterior region show open bite in the anterior region.
Infantile Swallow (or) Tongue between Gum Pads:
As you can see from the above 2 conditions that the anterior region of the Gum pads do not come in contact with each other. Hence to swallow an infant has to close the space created by the Open Bite, the tongue is used to close the space by placing it between the upper and lower gum pads during swallowing.
The features of Infantile swallowing outlined by Moyer are as follows:
- The jaws are apart and the tongue is placed between the upper and lower gum pads.
- The mandible is stabilized by the contraction of the muscles of the seventh cranial nerve and the interposed tongue.
- The swallow is guided and to a large extent controlled by the sensory interchange between the lips and the tongue
Primary Dentition Period:
Anterior Deep Bite:
Deep Bite occurs in the initial stages of development. Deep bite is accentuated by the fact that the deciduous incisors are more upright than their successors the Permanent Incisors. the lower incisal edges come in contact with the cingulum area of the maxillary incisors. The deep bite is later reduced due to:
- Eruption of Deciduous Molars – which come into occlusion and increase the vertical dimension
- Attrition of incisors
- Forward movement of the mandible due to growth
Flush Terminal Plane:
The Mesio Distal relationship between the distal surfaces of the upper and lower second deciduous molars is called a terminal plane. The Distal surface of the upper and lower second deciduous molars are in one vertical plane. This relation is also called as Vertical Terminal plane. this is a normal feature of the deciduous dentition.
With the presense of Flush Terminal plane in the deciduous dentition we can say that the occlusal relationship in the permanent dentition is going to be normal.
These are also called as Simian Spaces or Anthropoid Spaces or Physiological Spaces or Developmental Spaces.
Spacing is usually present between the Deciduous Teeth. the presence of spaces between the deciduous teeth is important for the normal development of the permanent dentition. Absence of spaces in the primary dentition is an indication that crowding of the teeth may occur when the larger permanent teeth erupt.
These Spaces are seen:
- Mesial to the Maxillary Canine
- Distal to the Mandibular Canine
These spaces are useful in placement of the canine cusps in the opposing arch.
End on Relation of First Permanent Molar:
End on End relation is obtained in the mixed dentition period following the Flush terminal plane relation in the deciduous dentition. The flush terminal relation between the decicuous 2nd molars leads to the End on relation of the First permanent molar.
Ugly Duckling Stage:
Due to the eruption of the maxillary Canines at 10-12yrs of age there is a transient or self correcting malocclusion seen in the maxillary incisor region. This condition usually corrects itself when the canines erupt and the pressure is transferred to the coronal area of the incisors.