The lower jaw.
The 8 bones of the cranium encase the brain.
The skull’s facial skeleton includes the nasal and cheek bones, maxilla, and mandible.
All except the mandible are fixed together by immovable joints.... skull
Structure of bone Bone is composed partly of ?brous tissue, partly of bone matrix comprising phosphate and carbonate of lime, intimately mixed together. The bones of a child are about two-thirds ?brous tissue, whilst those of the aged contain one-third; the toughness of the former and the brittleness of the latter are therefore evident.
The shafts of the limb bones are composed of dense bone, the bone being a hard tube surrounded by a membrane (the periosteum) and enclosing a fatty substance (the BONE MARROW); and of cancellous bone, which forms the short bones and the ends of long bones, in which a ?ne lace-work of bone ?lls up the whole interior, enclosing marrow in its meshes. The marrow of the smaller bones is of great importance. It is red in colour, and in it red blood corpuscles are formed. Even the densest bone is tunnelled by ?ne canals (Haversian canals) in which run small blood vessels, nerves and lymphatics, for the maintenance and repair of the bone. Around these Haversian canals the bone is arranged in circular plates called lamellae, the lamellae being separated from one another by clefts, known as lacunae, in which single bone-cells are contained. Even the lamellae are pierced by ?ne tubes known as canaliculi lodging processes of these cells. Each lamella is composed of very ?ne interlacing ?bres.
GROWTH OF BONES Bones grow in thickness from the ?brous tissue and lime salts laid down by cells in their substance. The long bones grow in length from a plate of cartilage (epiphyseal cartilage) which runs across the bone about 1·5 cm or more from its ends, and which on one surface is also constantly forming bone until the bone ceases to lengthen at about the age of 16 or 18. Epiphyseal injury in children may lead to diminished growth of the limb.
REPAIR OF BONE is e?ected by cells of microscopic size, some called osteoblasts, elaborating the materials brought by the blood and laying down strands of ?brous tissue, between which bone earth is later deposited; while other cells, known as osteoclasts, dissolve and break up dead or damaged bone. When a fracture has occurred, and the broken ends have been brought into contact, these are surrounded by a mass of blood at ?rst; this is partly absorbed and partly organised by these cells, ?rst into ?brous tissue and later into bone. The mass surrounding the fractured ends is called the callus, and for some months it forms a distinct thickening which is gradually smoothed away, leaving the bone as before the fracture. If the ends have not been brought accurately into contact, a permanent thickening results.
VARIETIES OF BONES Apart from the structural varieties, bones fall into four classes: (a) long bones like those of the limbs; (b) short bones composed of cancellous tissue, like those of the wrist and the ankle; (c) ?at bones like those of the skull; (d) irregular bones like those of the face or the vertebrae of the spinal column (backbone).
The skeleton consists of more than 200 bones. It is divided into an axial part, comprising the skull, the vertebral column, the ribs with their cartilages, and the breastbone; and an appendicular portion comprising the four limbs. The hyoid bone in the neck, together with the cartilages protecting the larynx and windpipe, may be described as the visceral skeleton.
AXIAL SKELETON The skull consists of the cranium, which has eight bones, viz. occipital, two parietal, two temporal, one frontal, ethmoid, and sphenoid; and of the face, which has 14 bones, viz. two maxillae or upper jaw-bones, one mandible or lower jaw-bone, two malar or cheek bones, two nasal, two lacrimal, two turbinal, two palate bones, and one vomer bone. (For further details, see SKULL.) The vertebral column consists of seven vertebrae in the cervical or neck region, 12 dorsal vertebrae, ?ve vertebrae in the lumbar or loin region, the sacrum or sacral bone (a mass formed of ?ve vertebrae fused together and forming the back part of the pelvis, which is closed at the sides by the haunch-bones), and ?nally the coccyx (four small vertebrae representing the tail of lower animals). The vertebral column has four curves: the ?rst forwards in the neck, the second backwards in the dorsal region, the third forwards in the loins, and the lowest, involving the sacrum and coccyx, backwards. These are associated with the erect attitude, develop after a child learns to walk, and have the e?ect of diminishing jars and shocks before these reach internal organs. This is aided still further by discs of cartilage placed between each pair of vertebrae. Each vertebra has a solid part, the body in front, and behind this a ring of bone, the series of rings one above another forming a bony canal up which runs the spinal cord to pass through an opening in the skull at the upper end of the canal and there join the brain. (For further details, see SPINAL COLUMN.) The ribs – 12 in number, on each side – are attached behind to the 12 dorsal vertebrae, while in front they end a few inches away from the breastbone, but are continued forwards by cartilages. Of these the upper seven reach the breastbone, these ribs being called true ribs; the next three are joined each to the cartilage above it, while the last two have their ends free and are called ?oating ribs. The breastbone, or sternum, is shaped something like a short sword, about 15 cm (6 inches) long, and rather over 2·5 cm (1 inch) wide.
APPENDICULAR SKELETON The upper limb consists of the shoulder region and three segments – the upper arm, the forearm, and the wrist with the hand, separated from each other by joints. In the shoulder lie the clavicle or collar-bone (which is immediately beneath the skin, and forms a prominent object on the front of the neck), and the scapula or shoulder-blade behind the chest. In the upper arm is a single bone, the humerus. In the forearm are two bones, the radius and ulna; the radius, in the movements of alternately turning the hand palm up and back up (called supination and pronation respectively), rotating around the ulna, which remains ?xed. In the carpus or wrist are eight small bones: the scaphoid, lunate, triquetral, pisiform, trapezium, trapezoid, capitate and hamate. In the hand proper are ?ve bones called metacarpals, upon which are set the four ?ngers, each containing the three bones known as phalanges, and the thumb with two phalanges.
The lower limb consists similarly of the region of the hip-bone and three segments – the thigh, the leg and the foot. The hip-bone is a large ?at bone made up of three – the ilium, the ischium and the pubis – fused together, and forms the side of the pelvis or basin which encloses some of the abdominal organs. The thigh contains the femur, and the leg contains two bones – the tibia and ?bula. In the tarsus are seven bones: the talus (which forms part of the ankle joint); the calcaneus or heel-bone; the navicular; the lateral, intermediate and medial cuneiforms; and the cuboid. These bones are so shaped as to form a distinct arch in the foot both from before back and from side to side. Finally, as in the hand, there are ?ve metatarsals and 14 phalanges, of which the great toe has two, the other toes three each.
Besides these named bones there are others sometimes found in sinews, called sesamoid bones, while the numbers of the regular bones may be increased by extra ribs or diminished by the fusion together of two or more bones.... bone
Thrush is characterised by the presence of white patches on the mucous membrane which bleeds if the patch is gently removed. It is caused by the growth of a parasitic mould known as Candida albicans. Antifungal agents usually suppress the growth of candida. Candidal in?ltration of the mucosa is often found in cancerous lesions.
Leukoplakia literally means a white patch. In the mouth it is often due to an area of thickened cells from the horny layer of the epithelium. It appears as a white patch of varying density and is often grooved by dense ?ssures. There are many causes, most of them of minor importance. It may be associated with smoking, SYPHILIS, chronic SEPSIS or trauma from a sharp tooth. Cancer must be excluded.
Stomatitis (in?ammation of the mouth) arises from the same causes as in?ammation elsewhere, but among the main causes are the cutting of teeth in children, sharp or broken teeth, excess alcohol, tobacco smoking and general ill-health. The mucous membrane becomes red, swollen and tender and ulcers may appear. Treatment consists mainly of preventing secondary infection supervening before the stomatitis has resolved. Antiseptic mouthwashes are usually su?cient.
Gingivitis (see TEETH, DISEASES OF) is in?ammation of the gum where it touches the tooth. It is caused by poor oral hygiene and is often associated with the production of calculus or tartar on the teeth. If it is neglected it will proceed to periodontal disease.
Ulcers of the mouth These are usually small and arise from a variety of causes. Aphthous ulcers are the most common; they last about ten days and usually heal without scarring. They may be associated with STRESS or DYSPEPSIA. There is no ideal treatment.
Herpetic ulcers (see HERPES SIMPLEX) are similar but usually there are many ulcers and the patient appears feverish and unwell. This condition is more common in children.
Calculus (a) Salivary: a calculus (stone) may develop in one of the major salivary-gland ducts. This may result in a blockage which will cause the gland to swell and be painful. It usually swells before a meal and then slowly subsides. The stone may be passed but often has to be removed in a minor operation. If the gland behind the calculus becomes infected, then an ABSCESS forms and, if this persists, the removal of the gland may be indicated. (b) Dental, also called TARTAR: this is a calci?ed material which adheres to the teeth; it often starts as the soft debris found on teeth which have not been well cleaned and is called plaque. If not removed, it will gradually destroy the periodontal membrane and result in the loss of the tooth. (See TEETH, DISORDERS OF.)
Ranula This is a cyst-like swelling found in the ?oor of the mouth. It is often caused by mild trauma to the salivary glands with the result that saliva collects in the cyst instead of discharging into the mouth. Surgery may be required.
Mumps is an acute infective disorder of the major salivary glands. It causes painful enlargement of the glands which lasts for about two weeks. (See also main entry for MUMPS.)
Tumours may occur in all parts of the mouth, and may be BENIGN or MALIGNANT. Benign tumours are common and may follow mild trauma or be an exaggerated response to irritation. Polyps are found in the cheeks and on the tongue and become a nuisance as they may be bitten frequently. They are easily excised.
A MUCOCOELE is found mainly in the lower lip.
An exostosis or bone outgrowth is often found in the mid line of the palate and on the inside of the mandible (bone of the lower jaw). This only requires removal if it becomes unduly large or pointed and easily ulcerated.
Malignant tumours within the mouth are often large before they are noticed, whereas those on the lips are usually seen early and are more easily treated. The cancer may arise from any of the tissues found in the mouth including epithelium, bone, salivary tissue and tooth-forming tissue remnants. Oral cancers represent about 5 per cent of all reported malignancies, and in England and Wales around 3,300 people are diagnosed annually as having cancer of the mouth and PHARYNX.
Cancer of the mouth is less common below the age of 40 years and is more common in men. It is often associated with chronic irritation from a broken tooth or ill-?tting denture. It is also more common in those who smoke and those who chew betel leaves. Leukoplakia (see above) may be a precursor of cancer. Spread of the cancer is by way of the lymph nodes in the neck. Early treatment by surgery, radiotherapy or chemotherapy will often be e?ective, except for the posterior of the tongue where the prognosis is very poor. Although surgery may be extensive and potentially mutilating, recent advances in repairing defects and grafting tissues from elsewhere have made treatment more acceptable to the patient.... mouth, diseases of
Cleft palate and hare-lip should be recti?ed by operation, because both are a serious drawback to feeding in early life – while later, harelip is a great dis?gurement, and the voice may be affected. The lip may be dealt with at any time from the neonatal period to a few weeks, depending on the individual surgeon’s view of when the best result is likely to be achieved. Prior to operation, special techniques may be necessary to ensure adequate feeding such as the use of special teats in formula-fed babies. The closure of a large cleft in the palate is a more formidable operation and is better performed when the face has grown somewhat, perhaps at 6–12 months. The operations performed vary greatly in details, but all consist in paring the edges of the gap and drawing the soft parts together across it.
Further operations may be required over the years to improve the appearance of the nose and lip, to make sure that teeth are even, and to improve speech.
Parents of such children can obtain help and advice from the Cleft Lip and Palate Association (CLAPA).... palate, malformations of
The condition is irreversible thus no cure is possible. However, pituitary gland normalisers can assist and possibly avert decline.
Alternatives. Tea: Combine equal parts: Gotu Kola, Yarrow, Horsetail. 1 heaped teaspoon to each cup boiling water; infuse 15 minutes. 1 cup once or more daily.
Tablets/capsules. Bladderwrack, Borage, Kelp, Liquorice, Ginseng, Wild Yam, Damiana, Helonias. Formula. Combine: Sarsaparilla 1; Ginseng 1; Fringe Tree half; Thuja quarter. Dose: Powders, quarter of a teaspoon. Liquid extracts: 30-60 drops. Tinctures: 1-2 teaspoons. In water, morning and evening. ... acromegaly
Treatment. BHP (1983) recommends: Meadowsweet, Balm of Gilead, Poke root, Bogbean, Hart’s Tongue fern, Mountain Grape.
Teas: Singly or in combination (equal parts): Chamomile, Bogbean, Nettles, Yarrow. 1-2 teaspoons to each cup boiling water; infuse 5-10 minutes. 1 cup thrice daily before meals.
Tablets/capsules. Blue Flag root, Dandelion root, Poke root, Prickly Ash bark.
Formula. White Poplar bark 2; Black Cohosh half; Poke root quarter; Valerian quarter; Liquorice quarter. Mix. Dose: Powders: 500mg (two 00 capsules or one-third teaspoon) (children 5-12 years: 250mg – one 00 capsule or one-sixth teaspoon). Liquid extracts: 1 teaspoon: (children 5-12: 3-10 drops). Tinctures: 2 teaspoons: (children 5-12: 5-20 drops).
Evening Primrose oil. Immune enhancer.
Topical. Hot poultice: Slippery Elm, Mullein or Lobelia.
Diet: Lacto vegetarian. Kelp. Comfrey tea. Molasses. Low fat.
General. Adequate rest, good nursing, gentle manipulation but no massage to inflamed joints. Natural lifestyle. Parental emotional support.
Oily fish. See entry. ... arthritis, juvenile, chronic
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