Maxilla

Subperiosteal. The subperiosteal implants are placed on the residual bony ridge and are not osseointegrated. This implant is most commonly used in the mandible but sometimes is used in the maxilla. Subperiosteal implants have been installed since the 1940s (311) and still have a success rate after five years of only 50 to 60%. A success rate of over 90% for five years and 50% for 15 years also has been quoted (312). Subperiosteal implants are fitted by casting, which is an individual procedure. The casting can be coated with a porous metal coating or other coating and then put in the patient. This may result in an improvement for these implants. 

Aseptic necrosis of ball-and-socket joints (shoulder and hip) prostheses may be needed due to permanent damage bone marrow hyperplasia resulting in growth disturbances of maxilla and vertebrae Asplenia (autosplenectomy or surgical splenectomy)... 

Yellow phosphorus burns spontaneously in air, and the vapor released is irritating to the respiratory tract. The early signs of systemic intoxication by phosphorus are abdominal pain, jaundice, and a garlic odor of the breath prolonged intake may cause anemia, as well as cachexia and necrosis of bone, involving typically the maxilla and mandible (phossy jaw). In chronic phosphorus intoxication, lowered potassium blood levels or increased chloride concentrations along with leukopenia have also been reported. ... 

Skull Pre-maxillae, nasals, frontals, parietals, interparietal, occipitals (supraoccipital, occipital condyles, basioccipital), zygomatics, squamosals, lacrimals, tympanic bullae, mandibles, hyoid, palatine bone, vomer, presphenoid, basisphenoid, maxillae Figs. 1, 2, 3, and 4. 

Rotate fetus on its back to examine skull from ventral aspect examine basioccipitals, basisphenoid, incisors, nasals, nasal cartilages, squamosals, tympanic bullae, maxillae, and zygomatic arches and rotate skull to also examine the lateral aspects. 

The branchial pouches should be apparent between each respective arch, and the first and second arch should be discernible as two separate structures, although they can touch (Fig. 12a). The upper portion of the first arch (which gives rise to the maxilla) is also included in this assessment. 

Eirst arch (maxilla region)—small/ narrow... 

Olfactory Superior Middle turbinate Inferior turbinate Vestibule Maxilla... 

Jakhi SA, Parekh BK, Gupta S. 1983. Phosphoms necrosis of the maxilla. J Oral Med 38 174-176. 

Advancing or retracting the needle may be necessary to obtain a maxilla volume. 

Electrophysiological experiments to determine the relative abilities of contact chemoreceptors to perceive E, 20E and PoA in larvae of Mamestra brassicae [40], Bombyx mori, Spodoptera littoralis and Ostrinia nubilalis [118], In M brassicae a specific cell is present in the lateral sensilla of the maxilla which responds to 20E and PoA, but not to E. In B. mori, the medial sensilla were responsive to 20E and PoA, but not E. This finding confirmed previous observations [39], Both lateral and medial sensilla were responsive to E, 20E and PoA in O. nubilalis, with a... 

Osztramos. The discovery of these finds is partly a matter of collecting techniques (the separate teeth may be obtained by washing through sifts with 0.5 mm mesh size), though in the material in question complete maxillae and mandibles have also been found. 

The wolf find is interesting in that the praemolar of the maxilla occupies a somewhat intermediate position between Canis mosbachensis and C. lupus spelaeus, although tending to the latter form (Janossy, 1969a) (Fig. 26). 

Crude efforts were made to assess the effect of the removal of the maxillary palps and maxillae, both accessory mouth parts with many receptors assumed to be connected with the senses of taste or smell. The results were inconclusive, since insects so operated on refused to feed on either treated or untreated leaves, although this could also be interpreted to indicate that 24,055 had the same effect as removal of the sensory receptors—that is, it inhibited the response of the receptors so that the insect failed to recognize the treated material as food. 

Infraorbital Infraorbital Lower eyelid, medial aspect of cheek, part of the inner canthus and lacrimal sac, upper lip and lateral portion of nose 2 ml of anesthetic at the mouth of the infraorbital foramen located as a palpable, small depression in the maxilla, two-thirds of an inch inferior to the midpoint of the lower eyelid... 

Figure 1 Anterior view of an anencephalic human fetus. Notice the low-set ears, elevated nose and maxilla, the short neck (due to anomalies of the cervical vertebrae), and the prominent, protruding rudimentary brain. (Reproduced from Marin-Padilla M (1991) Cephalic axial skeletal-neural dysraphic disorders Embryology and pathology. Canadian Journal of Neurological Sciences 8 153-169, with permission.)...

Chronic ingestion and/or inhalation of phosphorus may result in osteomyelitis and bone necrosis. Signs and symptoms of this condition include bone inflammation, spontaneous bone fractures, anemia, and weight loss. A typical example of this condition is phossy jaw . This condition is caused by the absorption of phosphorus fumes through teeth cavities. Once absorbed, phosphorus attacks and destroys the bones of the mandible and maxilla. The extent of facial bone loss can be so severe that the bone necrosis may extend from the maxilla to the eye orbits. Phossy jaw is an irreversible and usually fatal condition. 

In many cases, gingival hyperplasia is accompanied by painful and bleeding gums. There is often superimposed secondary bacterial gingivitis. This can be so extensive that the teeth of the maxilla and mandible are completely overgrown. 

Intramembranous ossification is responsible for most of the mineralization of the skull, including the maxilla and mandible. It begins with the differentiation and activation of osteoblasts from fibroblast-related precursors within a region of connective tissue that demarcates where the bone will develop. The osteoblasts secrete a nonmineralized protein-rich (osteoid) matrix and, as they move away, the matrix mineralizes (Fig. 9.3a). The periosteum remains uncalcified and contains latent and undifferentiated osteoblasts for bone remodeling. Odontoblasts (Ob) and cementoblasts secrete an osteoid-like matrix similar to that of intramembraneous ossification. 

Mr. Smith is affected with Crouzon s syndrome (123500) and has craniosynostosis (i.e., premature closure of the skull sutures) along with unusual facies that includes proptosis secondary to shallow orbits, hypoplasia of the maxilla, and a prominent nose. His son and brother are also affected, although two daughters and his wife are not. Mr. and Mrs. Smith are considering having another child. Their physician counsels them that the risk that the child will be affected with Crouzon s syndrome is... 

Small cell neuroendocrine carcinomas similar to those seen in the lung are exceptionally rare in the nasal cavity and paranasal sinuses. They affect both sexes equally and occur over a broad age range (38 to 68 years in one studyThey may arise either in the nasal cavity or in the paranasal sinuses, especially the ethmoid and maxilla. Though some tumors will remain localized to the site of origin, higher grade tumors are likely to invade into adjacent structures such as the orbit, cribriform plate, or cranial cavity. 

Studies of heritable tumor syndromes have provided considerable insight into the molecular basis of the corresponding sporadic tumors. Mutations of the HRPT2 gene are responsible for the development of the hyperparathyroidism-jaw tumor (HPT-JT) syndrome, which is inherited as an autosomal dominant trait. The commonest manifestations of this syndrome include primary hyperparathyroidism, fibro-osseous lesions of the mandible and maxilla, and a variety of renal lesions. In this syndrome, hyperparathyroidism occurs as a result of neoplasms of one or more parathyroid glands, which... 

Maxilla GF, Tyrannic L, Caen G, et al. 1966. Effects of thyrocalcitonin on bone and renal excretion of calcium 45 and strontium 85 in the rat. Foliar Endocrinol 19(1) 7-13. 

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