A balanced face refers to a face having the same or similar proportions of 3 regions in length, that are formed by 4 points of the forehead hairline, eye brows, nasal tip and mentum when the face is divided from the bottom to top into three sections If the bottom section of those three is shorter than the other 2 sections or looks retruded, then the mandible looks like a bird’s jaw.
The ideal lateral shape can be formed when the upper lip is positioned about 2 to 3 mm backwards and the lower lip positioning about 1 to 2 mm backwards from a line connecting the nasal tip to the mentum.
If the mandible is deviated from such ideal shape, there are various reasons to be considered such as the nose is too flat, or the chin would be sunken a lot, or the lips are protruded.
But the most common cause is the weak and less developed mentum creating the short chin.
The Types of Short chin
When the arrangement of teeth (dentition) is normal
This is the case showing normal dentition when the upper teeth and the lower teeth are occluded. Because there is no problem in the dentition, it is relatively easy to fix with a surgical treatment which is a simple surgical operation.
Also the prevalence of short chin is relatively large, so any patients who see themselves as suffering from short chin, it is highly probable that they fall into this category.
It is called Microgenia in English, and in this case, the treatment can be done by Genioplasty a procedure to cut the mental bone and move it forward, or by insertion of an implant. The operation can be done in a short period of time so the swelling is relatively minimal and also the surgical effects are excellent.
When the dentition does not fit together (micrognathia)
The patient not only has a short chin but also the lower teeth are unnaturally positioned at the rear side compared to the front teeth when the upper and lower teeth are occluded. In this case not only the mandibular mentum but the entire mandible including the teeth has deteriorated in their growth. In this case it is being called as Micrognathia in English.
Patients with micrognathia can have breathing problem because they cannot close their mouths well enough due to relatively big tongue at young age, but the number is not that high among the patients who complain about short chin. In order to treat this condition, a dental correction has to be done and also the entire mandible including teeth has to be moved forward by a surgical operation.