The hard palate is a thin horizontal

plate made up of two bones of the

facial skeleton The facial skeleton comprises the ''facial bones'' that may attach to build a portion of the skull The skull is a bone A bone is a Stiffness, rigid tissue (anatomy), tissue that constitutes part of the skeleton in most vertebrate animals. ...

, located in the roof of the mouth. The bones are the

palatine process of the maxilla In human anatomy of the mouth In animal anatomy Anatomy (Greek ''anatomē'', 'dissection') is the branch of biology concerned with the study of the structure of organism In biology, an organism (from Ancient Greek, Greek: ὀργαν ...

and the

horizontal plate of palatine bone The horizontal plate of palatine bone is a quadrilateral part of the palatine bone In anatomy Anatomy (Greek ''anatomē'', 'dissection') is the branch of biology concerned with the study of the structure of organism In biology, an orga ...

. The hard palate spans the

alveolar arch The alveolar process () (also called the alveolar bone) is the thickened ridge of bone A bone is a Stiffness, rigid tissue (anatomy), tissue that constitutes part of the vertebrate skeleton in animals. Bones protect the various organs of the bo ...

formed by the

alveolar process The alveolar process () (also called the alveolar bone) is the thickened ridge of bone A bone is a Stiffness, rigid tissue (anatomy), tissue that constitutes part of the vertebrate skeleton in animals. Bones protect the various organs of the bo ...

that holds the upper

teeth A tooth (plural teeth) is a hard, calcified Calcification is the accumulation of calcium salts in a Tissue (biology), body tissue. It normally occurs in the formation of bone, but calcium can be deposited abnormally in soft tissue,Miller, J. ...

teeth

(when these are developed).

Structure

The hard palate is formed by the

and

. It forms a partition between the nasal passages and the

mouth In animal anatomy Anatomy (Greek ''anatomē'', 'dissection') is the branch of biology concerned with the study of the structure of organism In biology, an organism (from Ancient Greek, Greek: ὀργανισμός, ''organismos'') is ...

mouth

. On the anterior portion of the hard palate are the plicae, irregular ridges in the mucous membrane that help facilitate the movement of food backward towards the larynx. This partition is continued deeper into the mouth by a fleshy extension called the

soft palate The soft palate (also known as the velum, palatal velum, or muscular palate) is, in mammal Mammals (from Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was origin ...

. On the ventral surface of hard palate, some projections or transverse ridges are present which are called as palatine rugae.

Function

The hard palate is important for feeding and speech. Mammals with a defective hard palate may die shortly after birth due to inability to suckle. It is also involved in

mastication Chewing or mastication is the process by which food Food is any substance consumed to provide Nutrient, nutritional support for an organism. Food is usually of plant, animal or Fungus, fungal origin, and contains essential nutrients, such a ...

in many species. The interaction between the

tongue The tongue is a muscular organ (anatomy), organ in the mouth of a typical tetrapod. It manipulates food for mastication and swallowing as part of the digestive system, digestive process, and is the primary organ of taste. The tongue's upper surfa ...

tongue

and the hard palate is essential in the formation of certain

speech Speech is human vocal communication Communication (from Latin Latin (, or , ) is a classical language A classical language is a language A language is a structured system of communication Communication (from Latin ''c ...

sounds, notably high-front vowels,

palatal consonant Palatal consonants are consonant In articulatory phonetics The field of articulatory phonetics is a subfield of phonetics Phonetics is a branch of linguistics that studies how humans produce and perceive sounds, or in the case of sign lan ...

s, and

retroflex consonant A retroflex, apico-domal, or cacuminal () consonant is a coronal consonant where the tongue has a flat, concave, or even curled shape, and is articulated between the alveolar ridge and the hard palate. They are sometimes referred to as cerebral ...

s such as like "see", like "yes", �(realization of /hj/ in English) like "hue", and �(/r/, only for some speakers) like "red".

Clinical significance

Cleft palate

In the

birth defect A birth defect, also known as a congenital disorder, is a condition present at birth Birth is the act or process of bearing or bringing forth offspring, also referred to in technical contexts as parturition. In mammals, the process is initiat ...

called

cleft palate A cleft lip contains an opening in the upper lip Lips are a visible body part at the mouth of many animals, including humans. Lips are soft, movable, and serve as the opening for food intake and in the articulation of sound and speech. Hu ...

, the left and right portions of this plate are not joined, forming a gap between the mouth and nasal passage (a related defect affecting the face is

cleft lip A cleft lip contains an opening in the upper lip Lips are a visible body part at the mouth of many animals, including humans. Lips are soft, movable, and serve as the opening for food intake and in the articulation of sound and speech. Hu ...

). While a cleft palate has a severe impact upon the ability to

nurse Nursing is a profession within the health care Healthcare is the maintenance or improvement of health Health is a state of physical, mental and social well-being Well-being, also known as ''wellness'', ''prudential value'' or ''qua ...

nurse

and speak, it is now successfully treated through reconstructive

surgical Surgery ''cheirourgikē'' (composed of χείρ, "hand", and ἔργον, "work"), via la, chirurgiae, meaning "hand work". is a medical or dental specialty that uses operative manual and instrumental techniques on a person to investigate or t ...

procedures at an early age. This is the time where such procedures are available. Due to the complexity of this birth defect, researchers still do not know exactly what causes the cleft palate to develop during human development. Recently, these researchers found that even though there is no exact cause, there are several risk factors that drastically increase the risk of a baby being born with an orofacial cleft palate. As for the environmental risk factors, maternal smoking is the most influential risk factor. Based on a recent study of 103 German patients with cleft palates, it was found that 25.2% of them developed the defect due to excessive maternal smoking during pregnancy. While maternal smoking during pregnancy is a risk, there are also several genetic risk factors. Five SNP variants in the PAX7 gene affect development of facial features. These variations occur at six loci: 1p36, 2p21, 3p11.1, 8q21.3, 13q31.1 and 15q22. When tested in the European and Asian communities, these loci tests had a 95% acceptance rate. Besides the PAX 7 gene variants, there were also five possible mutations found in the transforming growth factor- alpha gene or TGFA gene that can lead to the development of a cleft palate. Even though several risk factors have been linked to cleft palates, more research much be done in order to determine the true causes of the defect.

Palatal abscess

Palatal

abscess An abscess is a collection of pus Pus is an exudate An exudate is a fluid emitted by an organism through pores or a wound, a process known as exuding or exudation. ''Exudate'' is derived from ''exude'', "to ooze", from the Latin Lat ...

abscess

es may also occur.

Hard palate pigmentation

Long-term use of the drug

chloroquine Chloroquine is a medication primarily used to prevent and treat malaria in areas where malaria remains sensitive to its effects. Certain types of malaria, resistant strains, and complicated cases typically require different or additional medi ...

diphosphatase, used in

malaria prophylaxisMalaria prophylaxis is the preventive treatment of malaria Malaria is a mosquito-borne infectious disease that affects humans and other animals. Malaria causes symptoms that typically include fever Fever, also referred to as pyrexia, is d ...

rheumatoid arthritis Rheumatoid arthritis (RA) is a long-term autoimmune disorder that primarily affects synovial joint, joints. It typically results in warm, swollen, and painful joints. Pain and stiffness often worsen following rest. Most commonly, the wrist and ...

and other conditions, was found to cause bluish - grey pigmentation in the hard palate.

References

{{DEFAULTSORT:Hard Palate Palate

palate The palate () is the roof of the mouth In animal anatomy Anatomy (Greek ''anatomē'', 'dissection') is the branch of biology concerned with the study of the structure of organism In biology, an organism (from Ancient Greek, Greek: ...

Speech organs ja:口蓋#硬口蓋