Entire Jaw Research Articles

Pediatric acute lymphocytic leukemia with osseous changes in jaws: Literature review and report of a case

A case of acute lymphocytic leukemia (ALL) in a child is presented. We also reviewed the recent literature of similar cases describing leukemic jaw bones involvement in Japan. Radiographic examinations of the patient disclosed diffuse osteolytic changes of the entire jaws, the corticated border of the crypts of developing teeth, loss of lamina dura, a thickened periodontal space and disappearance of the radiopaque lines that delineate the borders of the mandibular canal. Pronounced regression and restoration of the alveolar bone and the crypts were detectable on the radiographs taken after a course of the treatment for ALL.

The maximum average bite force for a given jaw length

Major osteological landmarks were used to prepare idealized drawings of mammalian and reptilian lower jaws. Measurements from these drawings allowed the average output or bite force, along the entire jaw, to be calculated for many different anteroposterior positions of the input or muscle force. In the mammalian drawing, the maximum average bite force is exerted when the resultant force is located at about 30% of the way along the jaw from the joints. Because of geometric differences in the reptilian drawing, a resultant positioned at 20% of the way along the jaw exerts the maximum average bite force; a maximum force that is smaller than that in the mammalian case. The estimated location of the muscle resultant in actual cases corresponds to these calculated positions. Therefore, in real animals, the muscles are located in the position that produces the largest average force for any jaw length. The geometric changes necessary to transform the idealized reptilian drawing, with a smaller maximum average bite force, into that of the mammalian drawing, with a larger maximum force, are the same as those changes seen in the fossil record of the reptile/mammal transition. This finding suggests that the morphological changes that occurred in the jaws increased the average bite force in the primitive mammals.

4495632 Radiographic apparatus for photographic entire jaws : Kozo Nakano, Kyoto, Japan assigned to Kabushiki Kaisha Morita Seisakusho

4495632 Radiographic apparatus for photographic entire jaws : Kozo Nakano, Kyoto, Japan assigned to Kabushiki Kaisha Morita Seisakusho

4430746 Tomographic for photographing entire jaws : Masakaz Suzuki, Toshiaki Ikeda, Shuhe Furuichi, Shin Nakamachi, Japan assigned to Kabushiki Kaisha MOrita Seisakusho

4430746 Tomographic for photographing entire jaws : Masakaz Suzuki, Toshiaki Ikeda, Shuhe Furuichi, Shin Nakamachi, Japan assigned to Kabushiki Kaisha MOrita Seisakusho

Can Odontocetes Debilitate Prey with Sound?

In this paper we discuss an hypothesis. We marshall scattered supportive evidence, outline its problems, and explore its ramifications and suggest tests. We do not prove it. The hypothesis is that some odontocete cetaceans may emit sounds so intense that their prey is debilitated and capture made easier. Collateral to this idea is the possibility that this capability may have had profound effects on the evolution of modern cetaceans, to be found especially in their behavior and anatomy. At this point the idea seems to have appeared briefly three times. This is the first full-scale review. The first to mention it were Bel'kovich and Yablokov (1963). They calculate, using the very high frequency of 196 kHz, that a sound intensity of 10 watts/cm2 (which corresponds to about 6.5 atmospheres pressure) might be developed and that it could be perceived as a powerful shock that could stun prey. They note that even a small dolphin might thus be able to stun prey. Next, Berzin (1971), after lengthy studies of the sperm whale (Physeter catodon), concluded that neither their teeth nor jaws were essential for food getting. He first noted that almost all food items in sperm whale stomachs are intact. Even very large squids and sharks measuring up to 3 m in length usually show no tooth marks. He continues: Moreover our material included up to ten sperms with well-filled or at least normally filled stomachs in which the entire jaw was either turned aside already at the very base, or turned inside out with the tooth row outward, or else rolled up in a ring, arch, etc.... In such animals not a single tooth nor even the jaw could take any part in gripping the prey. Analysis of all these data leads one to a conclusion which at first glance appears preposterous: there is reduction not only of the function of the teeth but also that of the entire lower jaw in the digestive process of the sperm whale. Only thus can the facts, which contradict what is generally accepted be explained. He proposes acoustic stunning as an hypothesis.

Nervous Control of Occlusion

Receptors that convey sensory information about occlusal relationships to the CNS are found in the teeth, periodontal ligaments, muscles of mastication, and the temporomandibular joints. This sensory information enters the CNS largely through the maxillary and mandibular divisions of the trigeminal nerve. Cell bodies of these afferent neurons are found in the trigeminal ganglion (exteroceptive) and mesencephalic nucleus (proprioceptive). Axons of exteroceptive neurons are segregated into those conveying general sensory modalities such as touch, which enter the main sensory nucleus, and those conveying pain and temperature, which descend in the spinal tract of V and enter the spinal nucleus of V. Axons of proprioceptive neurons terminate in the motor nucleus of the trigeminal nerve. Second order neurons of the main sensory and spinal nuclei of the trigeminal nerve project to the thalamus. Third order neurons from the thalamus project bilaterally to the frontal and parietal cortex. The muscles of mastication, responsible for mandibular movement, are innervated by alpha motor neurons from the motor nucleus of V. When these neurons are stimulated, the masticatory muscles contract. The motor nucleus receives fibers from the frontoparietal motor cortex, trigeminal sensory nuclei, cerebellum, contralateral reticular formation, hypothalamus, amygdaloid nucleus, caudate nucleus, tectum of the midbrain, and cranial nerve nuclei (especially VII, which controls the muscles of the mouth and cheek and XII, which controls the musculature of the tongue). Input from all of these areas controls the muscles of mastication through the alpha and gamma motor neurons. Occlusal forces are produced during mastication, swallowing, and other activities. Tooth contacts stimulate sensory neurons. This information is conveyed to the CNS and integrated, and the appropriate adjustment of the mandible is made. Many questions concerning how the nervous system controls occlusion remain unanswered. How do the nervous pathways for the control of occlusal forces differ for individuals with normal occlusion or malocclusion, or for edentulous individuals or those with dentures? If the receptors of the teeth or periodontal ligaments provide the primary sensory input for the muscles of mastication, then clearly the individual with dentures or the edentulous individual must utilize alternative pathways to provide the appropriate control. Why do some people with obvious malocclusion not experience pain and others with minor occlusal problems experience great discomfort in the temporomandibular joint? Perhaps it is genetic, or the pathways used by each of these individuals may differ. What is the effect of repositioning the teeth or the entire jaw on established neuronal pathways? Perhaps the pathways are modified, or they degenerate and other pathways are established.

Root morphogenesis in ectopically transplanted pleurodont teeth of the iguana

A study was made to determine the behavior and fate of transplanted reptilian teeth with a pleurodont type of attachment. The purpose was to compare this attachment with the behavior of other types of attachments, when they are transplanted, and to determine which portions of the ankylosed tooth are controlled by intrinsic factors. 50 small green iguanas were used. Autologous transplants of both individual buds of a known stage of development and small blocks of the entire upper or lower jaw were placed in the gular region or anterior chamber of the eye. The transplants and the jaws were examined at intervals from 0 to 180 days. Tooth buds transplanted with or without the jaw were capable of growth to normal size and shape. New bud formation also began after transplant acceptance, and buds were more protected from epithelial injury than previously reported amphibian tooth transplants. The ankylosed adult tooth began the process of shedding almost immediately. While lack of normal environment and lack of underlying bone did not prevent formation of a normal root shaft with dentin, there was little evidence of induction of the ‘bone of attachment’ and underlying jaw bone by the growing buds. The root shaft size and shape were, therefore, intrinsic features of the pleurodont tooth.

Sclerotic cemental masses of the jaws (so-called chronic sclerosing osteomyelitis, sclerosing osteitis, multiple enostosis, and gigantiform cementoma)

A series of thirty-eight cases of densely sclerotic lesions of the jaws was studied. The lesions were all at least 1.5 cm. in diameter. Pain, drainage, or localized expansion of the jaw was present in two thirds of the patients. Thirty-four of the thirty-eight patients were women, and twenty-five were negros. In fourteen instances, a radiographic survey of the entire jaws was available. Thirteen of these fourteen patients had multiple lesions which were usually symmetrically distributed throughout the jaws. In twenty-four patients radiographs of the lesional area only were available for review. In thirty-four of the thirty-eight cases (89 per cent), the sclerotic masses were interpreted as cementum. Although this condition has previously been described as chronic sclerosing osteomyelitis, sclerosing osteitis, multiple enostosis, or gigantiform cementoma, it appears more appropriate to consider these lesions as part of the spectrum of the benign fibro-osseous lesions of periodontal ligament origin. Four of the sclerotic lesions, which were radiographically indistinguishable from the cemental lesions, consisted only of bone. Two of these appeared to be examples of true chronic sclerosing osteomyelitis, and two may be appropriately designated as enostosis or osteomas.

Cosmetic Correction of Severe Mandibular Retrusion

Retrusion of the mandible is characterized by posterior displacement of the entire lower jaw. It may be a unilateral or a bilateral deformity but is more frequently the latter. In all such defects of the lower jaw there is some degree of bony hypoplasia; often there is an actual loss of bone with much distortion of the anatomic structures of the mandible. Malocclusion is invariably present, and underdevelopment and recession of the symphysis may accentuate the deformity. The most conspicuous feature in all cases of mandibular retrusion is retraction of the chin; this may or may not be associated with shortening of the upper lip (Figs. 1 and 2). Retrusion of the mandible may be due to (1) malocclusion alone or (2) arrested growth of the lower jaw complicated by malocclusion. In all patients having mandibular retrusions resulting from malocclusion and characterized by a distal relationship of the lower to

Clinical pantomography of the jaws.

Pantomography is a procedure which has been developed for the purpose of obtaining laminagrams of curved surfaces. This method employs a fixed source of radiation, while object and film are rotated on holders having equal radii and moving at equal speed through a peripheral frictional arrangement. The rather narrow roentgen beam reproduces on the film the layer of interest, which has the same linear velocity and direction of movement as the film itself. Structures outside this layer of equal linear velocity are blurred in the usual tomographic manner. The reproduced section, however, appears in essentially better detail than in conventional tomography. For concentric pantomography the object is placed concentrically on the holder. This technic is best suited to structures of considerable length, e.g., the entire jaw, though it may entail some lack of detailed definition. In eccentric pantomography, the object is placed eccentrically on the holder. Thus, only a portion will be reproduced, with some gain in...

Familial Fibrous Swelling of the Jaws

The familial occurrence of painless enlargement of the jaws was first reported by Jones in 1933 (4) in three siblings, six, five, and four years of age. In 1938 (5) Jones reported later observations on the same family under the title “Familial Multilocular Cystic Disease of the Jaws.” He concluded from roentgenograms that the condition was due to multiple dentigerous cysts affecting the entire upper and lower jaws and accompanied by chronic enlargement of the lymph nodes in the submaxillary regions. The disorder first became evident when the patients were between two and a half and three years of age. Earlier generations of this family had not exhibited signs of the disease. Jones mentions that Dr. P. J. Thomas of Savannah, Ga., had observed a boy with similar multilocular enlargement of both jaws; in this family, however, enlarged jaws were said to have been present in five successive generations. In 1947 (7), Miller described hypertrophy of the jaws in a young man eighteen years of age, whose mother was...

THE SURGICAL TREATMENT OF CERTAIN DEFORMITIES OF THE JAW ASSOCIATED WITH MALOCCLUSION OF THE TEETH

With the development in orthodontic practice it is surprising that so little advance has been made in the surgical treatment of prognathism, receding maxilla and other marked deformities of the jaw producing malocclusion. In the main the text-books on oral surgery contain no reference to the subject and little is to be found in modern treatises of surgery. In Von Bergmann's elaborate "System of Surgery," however, four lines relate that in a successful attempt to improve the deformity of a receding chin, Von Bergmann made an extensive resection of all of the processes, including the coronoid process, and subsequently displaced the entire jaw by the aid of an artificial dental apparatus. <h3>HISTORY OF THE SUBJECT</h3> Over sixty years have lapsed since Dr. S. P. Hullihen,¹of Wheeling, Ga., successfully devised and performed an osteoplastic resection of the jaw, yet the modern works on dental practice and orthodontia mention

II. On the affinities of thylacoleo

Since the communication of the paper “On Thylacoleo,” in the “Philosophical Transactions” for 1871, further explorations of the caves and breccia-fissures in Wellington Valley, New South Wales, have been made, by a grant for that purpose from the Legislature of the Colony, and carried out by E. B. Ramsay, Esq., F. L. S., Curator of the Museum of Natural History, Sydney. The present paper treats of the fossils contributing to the further restoration of the great carnivorous Marsupial ( Thylacoleo carnifex , Ow.). They exemplify the entire dentition in situ of the upper and lower jaws of a nature individual: the bones of the fore-limb, of which those of the antibrachium and the ungual phalanges are described, are compared with those of other Marsupials, and of placental, especially feline, Carnivora . An entire lower jaw with the articular condyles adds to the grounds for determination of the habits and affinities of the extinct Marsupial. Figures of these fossils of the natural size accompany the paper.

Removal of Entire Upper Jaw for Malignant Disease

Removal of Entire Upper Jaw for Malignant Disease

On extirpation of the entire upper jaw, illustrated by a case in which it was removed, together with the whole of the palate bone, on account of a large fibro-vascular tumour springing from the antrum

On extirpation of the entire upper jaw, illustrated by a case in which it was removed, together with the whole of the palate bone, on account of a large fibro-vascular tumour springing from the antrum