There is a small size difference between the lower jaw and the mandible in micrognathia. In addition to affecting the face's appearance and function, micrognathia can also affect breathing and feeding. It can be present at birth or develop later in life. It can be caused by various genetic or environmental factors, and it can be associated with other syndromes or conditions. We will discuss the causes, symptoms, diagnosis, treatment, and prevention of micrognathia in this blog post.
There are several possible causes of micrognathia, depending on whether it is congenital (present at birth) or acquired (developed later in life).
Genetic factors: Micrognathia can be inherited from one or both parents, or it can result from a random genetic mutation. Pierre Robin syndrome, trisomy 13, trisomy 18, achondrogenesis, progeria, and cri-du-chat syndrome are some genetic syndromes that can cause micrognathia.
Micrognathia can also be caused by exposure to harmful substances or infections during pregnancy, including alcohol, tobacco, drugs, pesticides, rubella, cytomegalovirus, and Zika.
An injury or illness that affects the lower jaw's growth or development can cause micrognathia. Some examples include fractures, dislocations, infections, tumors, arthritis, and ankylosis.
Having a small lower jaw that does not match the size of the rest of the face is a symptom of micrognathia. The lower jaw may also be set back or positioned abnormally in relation to the upper jaw.
Micrognathia may also cause the following symptoms:
Breathing difficulties during sleep or while lying down. This can lead to snoring, sleep apnea, or cyanosis (bluish skin color).
Poor weight gain, malnutrition, or choking can result from difficulty feeding, chewing, or swallowing.
A crowded or misaligned mouth, an overbite, underbite, or crossbite are examples of dental problems.
Problems with speech, such as lisping, slurring, or difficulty pronouncing certain sounds.
A sloping forehead, a flat or sunken nose, a cleft palate, or low-set ears are all examples of facial deformities.
Slow growth, intellectual disability, or learning difficulties.
Symptom severity may vary depending on the degree of micrognathia and other associated conditions.
Various methods can be used to diagnose micrognathia before or after birth. Some of these methods are:
A prenatal ultrasound is a test that uses sound waves to create images of the fetus inside the womb. It can detect micrognathia in the second and third trimesters.
Measure the head circumference and the distance between the chin and the chest of the newborn or child. These measurements are compared with the normal ranges for the child's age and gender.
Imaging tests such as X-rays, CT scans, and MRIs produce detailed pictures of bones and tissues in the face and skull. These tests can show the shape, size, and position of the lower jaw, as well as any abnormalities.
A genetic test analyzes a child's or parent's DNA to determine if any genetic mutations or syndromes can cause micrognathia.
Treatment for micrognathia depends on its cause, severity, and age. Some treatment options include:
If the micrognathia is mild or expected to improve with growth, the child is observed regularly to ensure no breathing or feeding problems develop.
A child is placed on his or her side or stomach, or propped up with pillows or a special device to prevent the tongue from falling back and blocking the airway.
For temporary relief of breathing problems, especially during sleep, a nasal-pharyngeal airway is inserted through the nose and into the throat.For temporary relief of breathing problems, especially during sleep, a nasal-pharyngeal airway is inserted through the nose and into the throat.
Tracheostomy: This is a surgical procedure in which an opening is made in the neck and a tube is inserted into the windpipe to bypass the blocked airway.
Using braces, retainers, or other devices that move teeth into a better position, orthodontic treatment corrects dental problems caused by micrognathia, such as crooked or crowded teeth.
Usually performed on children in their late teens or early twenties, orthognathic surgery repositions or reshapes the lower jaw to improve the appearance and function of the face.
By making small cuts in the bone and applying a device that pulls the bone segments apart, distraction osteogenesis gradually lengthens the lower jaw. The procedure is usually performed on young children or those with severe micrognathia who cannot undergo orthognathic surgery.
Although micrognathia may not be preventable in some cases, especially if it is caused by genetic factors, there are some preventive measures that may reduce the risk:
The purpose of prenatal care is to monitor the health of the mother and the fetus during pregnancy, as well as to detect and treat any complications or infections that may affect the lower jaw's development.
Micrognathia can be caused by certain diseases, such as rubella, that are vaccinated against during pregnancy.
Preventing or limiting exposure to substances that can harm the development of the lower jaw during pregnancy, such as alcohol, tobacco, drugs, or pesticides, is essential.
