Maxilla and Mandible

[vratisevojvodo]

Maxillary retrusion​

Maxillary retrusion, also called maxillary retrognathia or maxillary hypoplasia, is when the maxilla recedes with respect to the frontal plane of the forehead. A retruded maxilla can have detrimental effects on a person's aesthetics.

Maxillary retrusion can be prevented or reversed, during childhood, using an exercise conceived by the orthodontist Mike Mew. This exercise involves putting pressure on the roof of your mouth using your tongue, and should be done continuously throughout the day. This exercise not only protrudes the maxilla, but protrudes the zygomatic bones as well, because the zygomatic bones are connected to the maxilla.

Surgical procedures in correcting maxillary retrusion include LeFort I maxillary advancement, LeFort II maxillary advancement, or a LeFort III maxillary advancement.

Other terms associated with maxillary retrusion include: Midface retrusion Midface hypoplasia Midfacial retrusion Midfacial hypoplasia Midfacial retrognathia (used rarely)

Maxillary protrusion​

The reverse of maxillary retrusion is called maxillary protrusion or maxillary prognathia. Maxillary protrusion should not be confused with dentoalveolar protrusion, also called bidental protrusion, bialveolar protrusion, bimaxillary protrusion or bimax. (However, John Mew explains that bimaxillary protrusion is a misnomer.) Bimaxillary protrusion is an ethnic variation that has little influence to physical attractiveness.
Note that it is possible for one to have a bimax yet a retruded maxilla.

Narrow maxilla​

A narrow maxilla is a maxilla which does not have much lateral projection. It could be caused by poor oral posture. In narrow maxillas, the cheekbones do not project laterally much. Narrow dental arch. Palate expansion is used to correct a narrow maxilla. It could broaden cheekbones as well.

Downward maxilla​

A downward maxilla is a maxilla which falls downward or grows downward. It could be caused by poor oral posture. Those with a downward maxilla usually have downward orbital rims as well.

Maxillary impaction is a procedure which corrects a downward maxilla. A LeFort III could elevate the maxillozygomatic area, including the infraorbital rims, upward.

Causes of poor maxillary development​

- Poor oral posture
- Acidic diet
- Vitamin K insufficiency
- Poor head and body posture - Caused by sitting too much.
- Lack of hard foods
- Stress - Effects tongue position and head posture.
- Thumb sucking
- Allergies
- Sleep position
- Bottlefeeding
- Retractive orthodontic treatment (braces, headgear and extractions)
- Inflammation - leads to mucus production
- Poor diet - could lead to inflammation and allergies, leading to nasal blockage

Effects of poor maxillary development​

Eye area​

- Darkness under the eyes due to infraorbital retrusion.

Paranasal area​

Nose​

The nose is more pronounced in an ideal occlusion (straight teeth) but in the various malocclusions (crooked teeth) where the maxilla (top jaw) is underdeveloped it appears larger, although in fact it is smaller.
— John Mew

Dorsal hump ("hook nose") as the bottom cartilaginous part of the nose gets pulled inward by the retruded maxilla.

Lower third​

- More pronounced nasolabial folds.
- Marionette lines caused by unsupported soft tissue from the cheeks by retruded mandible.
- Pronounced separation of soft tissue between chin and cheeks.
- Unpronunced jawline caused by tucked-in soft tissue by retruded mandible.
- Stuffy cheeks
- Small teeth
- Crowded teeth

Health effects​

A retruded maxilla is maladaptive since it causes snoring, sleep apnea, insufficient oxygen intake and spinal imbalance.. So a retruded maxilla like all other facial deformities are selected against. A retruded maxilla pushes the tongue back thus obstructs the airway, causing snoring and sleep apnea. People with sleep apnea have 20% decreased life expectancy and increased risk for cardiovascular disease. Most stroke patients suffer from sleep apnea.
A retruded maxilla blocks the airway passage, which in turn makes people to move their heads forward to compensate. Forward head posture, however, places a load on the spine. It could increase spinal load by several pounds, inhibiting mobility and increasing needless effort to maintain balance.

Other effects

A protruded maxilla increases the volume of the resonance chamber, the mouth. This leads to richer vocalization. Singers have protruded maxilla and are more likely to be attractive. Example. Good looking actors like Johnny Depp and Brad Pitt have good voices.

Mandible​

The mandible is a bone of the lower face which includes the entire lower jaw, lower dental arch and teeth. Parts of the mandible include the chin, the base of the mandible and the ramus. A large, heavily developed mandible is an important feature of masculine faces. Heavily developed mandibles are broad and include projecting chins and long ramuses. Ramus length is affected by testosterone levels.

People with maxillary retrusion tend to have weakly developed mandibles—narrow palates, obtuse gonial angles, short base of mandible, and receding chins, which creates a weak appearance to the face.

A retruded or downward ramus will obstruct the airway. To compensate for the airway obstruction, the bottom of the ramus shifts forward. This will result in an increased gonial angle, which is a detriment to aesthetics.

Ramus length is more affected by testosterone rather than maxillary retrusion. However, a retruded maxilla will make the ramus appear less vertical, making it appear shorter as a result.

 

[ER enjoyer]

Maxillary retrusion​

Maxillary retrusion, also called maxillary retrognathia or maxillary hypoplasia, is when the maxilla recedes with respect to the frontal plane of the forehead. A retruded maxilla can have detrimental effects on a person's aesthetics.

Maxillary retrusion can be prevented or reversed, during childhood, using an exercise conceived by the orthodontist Mike Mew. This exercise involves putting pressure on the roof of your mouth using your tongue, and should be done continuously throughout the day. This exercise not only protrudes the maxilla, but protrudes the zygomatic bones as well, because the zygomatic bones are connected to the maxilla.

Surgical procedures in correcting maxillary retrusion include LeFort I maxillary advancement, LeFort II maxillary advancement, or a LeFort III maxillary advancement.

Other terms associated with maxillary retrusion include: Midface retrusion Midface hypoplasia Midfacial retrusion Midfacial hypoplasia Midfacial retrognathia (used rarely)

Maxillary protrusion​

The reverse of maxillary retrusion is called maxillary protrusion or maxillary prognathia. Maxillary protrusion should not be confused with dentoalveolar protrusion, also called bidental protrusion, bialveolar protrusion, bimaxillary protrusion or bimax. (However, John Mew explains that bimaxillary protrusion is a misnomer.) Bimaxillary protrusion is an ethnic variation that has little influence to physical attractiveness.
Note that it is possible for one to have a bimax yet a retruded maxilla.

Narrow maxilla​

A narrow maxilla is a maxilla which does not have much lateral projection. It could be caused by poor oral posture. In narrow maxillas, the cheekbones do not project laterally much. Narrow dental arch. Palate expansion is used to correct a narrow maxilla. It could broaden cheekbones as well.

Downward maxilla​

A downward maxilla is a maxilla which falls downward or grows downward. It could be caused by poor oral posture. Those with a downward maxilla usually have downward orbital rims as well.

Maxillary impaction is a procedure which corrects a downward maxilla. A LeFort III could elevate the maxillozygomatic area, including the infraorbital rims, upward.

Causes of poor maxillary development​

- Poor oral posture
- Acidic diet
- Vitamin K insufficiency
- Poor head and body posture - Caused by sitting too much.
- Lack of hard foods
- Stress - Effects tongue position and head posture.
- Thumb sucking
- Allergies
- Sleep position
- Bottlefeeding
- Retractive orthodontic treatment (braces, headgear and extractions)
- Inflammation - leads to mucus production
- Poor diet - could lead to inflammation and allergies, leading to nasal blockage

Effects of poor maxillary development​

Eye area​

- Darkness under the eyes due to infraorbital retrusion.

Paranasal area​

Nose​

The nose is more pronounced in an ideal occlusion (straight teeth) but in the various malocclusions (crooked teeth) where the maxilla (top jaw) is underdeveloped it appears larger, although in fact it is smaller.
— John Mew

Dorsal hump ("hook nose") as the bottom cartilaginous part of the nose gets pulled inward by the retruded maxilla.

Lower third​

- More pronounced nasolabial folds.
- Marionette lines caused by unsupported soft tissue from the cheeks by retruded mandible.
- Pronounced separation of soft tissue between chin and cheeks.
- Unpronunced jawline caused by tucked-in soft tissue by retruded mandible.
- Stuffy cheeks
- Small teeth
- Crowded teeth

Health effects​

A retruded maxilla is maladaptive since it causes snoring, sleep apnea, insufficient oxygen intake and spinal imbalance.. So a retruded maxilla like all other facial deformities are selected against. A retruded maxilla pushes the tongue back thus obstructs the airway, causing snoring and sleep apnea. People with sleep apnea have 20% decreased life expectancy and increased risk for cardiovascular disease. Most stroke patients suffer from sleep apnea.
A retruded maxilla blocks the airway passage, which in turn makes people to move their heads forward to compensate. Forward head posture, however, places a load on the spine. It could increase spinal load by several pounds, inhibiting mobility and increasing needless effort to maintain balance.

Other effects

A protruded maxilla increases the volume of the resonance chamber, the mouth. This leads to richer vocalization. Singers have protruded maxilla and are more likely to be attractive. Example. Good looking actors like Johnny Depp and Brad Pitt have good voices.

Mandible​

The mandible is a bone of the lower face which includes the entire lower jaw, lower dental arch and teeth. Parts of the mandible include the chin, the base of the mandible and the ramus. A large, heavily developed mandible is an important feature of masculine faces. Heavily developed mandibles are broad and include projecting chins and long ramuses. Ramus length is affected by testosterone levels.

People with maxillary retrusion tend to have weakly developed mandibles—narrow palates, obtuse gonial angles, short base of mandible, and receding chins, which creates a weak appearance to the face.

A retruded or downward ramus will obstruct the airway. To compensate for the airway obstruction, the bottom of the ramus shifts forward. This will result in an increased gonial angle, which is a detriment to aesthetics.

View attachment 3276679

Ramus length is more affected by testosterone rather than maxillary retrusion. However, a retruded maxilla will make the ramus appear less vertical, making it appear shorter as a result.

''oral posture''Like most of the flat/recessed/downgrowth maxilla mfs has mongolian skull thats why JFL