China
Africa
Explore chapters and articles related to this topic
State of the Art of Artificial Intelligence in Dentistry and Its Expected Future
Published in Lavanya Sharma, Mukesh Carpenter, Computer Vision and Internet of Things, 2022
Vukoman Jokanović, M. Živković, S. Živković
Maxillary sinusitis is an inflammation of the mucous membrane that is radio-graphically characterized by thickening of the mucosa >4 mm, lacking continuity of the bottom of the maxillary sinus, opacity, focal alveolar atrophy, and associated periodontal disease. CT and CBCT are the most suitable methods for detecting such indications. In conventional radiography, diagnostic inconveniences are influenced by the overlapping of the maxillary sinus, the sinus bone architectures of the face, which often gives false negative outcomes. DL algorithms enhance the diagnostic capability of conventional radiographic imaging, reducing the need for unnecessary frequent CT scanning of patients. In a diagnosis of maxillary sinusitis, DL systems show 87.5%–93% accuracy, which is better or at least comparable to the findings of experienced radiologists. Such help is especially valuable in diagnostic support to inexperienced radiologists [27,52].
Designing for Head and Neck Anatomy
Published in Karen L. LaBat, Karen S. Ryan, Human Body, 2019
The lower portion of the face, the jaw, provides protection as well as the motion essential for chewing and talking. The maxillae are the paired stationary upper jawbones which you can feel as a U-shaped structure holding your upper teeth. Each maxilla reaches all the way to the lower border of the eye and abuts the nasal bones medially and the zygomatic bone laterally. The mandible (lower jawbone), also U-shaped, is separate from the skull and holds the lower teeth. The temporomandibular joint (TMJ), the articulation between mandible and temporal bone, just in front of the ear canal, allows movement of the lower jaw so that you can talk and chew (inset, Figure 3.3). Keep the movement of the lower jaw (up, down, forward and back, and side-to-side) in mind when designing headgear that is strapped under the chin and/or worn while eating or talking.
Dental Radiography
Published in Paolo Russo, Handbook of X-ray Imaging, 2017
The maxilla forms the upper jaw and, thus, a large part of the facial bones. Its structure is complex and it contains many regions of interest for radiographic examination. As in the mandible, the alveolar process lies within the predominant focus of a dentist and, as such, also of dental radiographic evaluation. The paired maxillary sinuses have strong effects on the posterior teeth (premolars, molars) as pathological conditions in the sinuses may also invade the teeth and vice-versa. In addition, implant surgery often requires a specific procedure (sinus floor elevation) in which the basal part of the maxillary sinus has to be radiographically assessed before and sometimes also after surgery. Some radiographs are explicitly aiming at the maxilla. For instance, Waters projection (see Section 22.4.2.3.2.5) was developed to investigate the maxillary sinuses plus the sphenoidal (and frontal) sinuses. The maxillary bone is of complex geometry and forms the lateral wall and the floor of the nasal cavity. The latter may also lie in the focus of dental radiographic evaluation. As the maxilla also forms the bony floor of the orbits, radiographic examination will inherently expose the eye to some radiation. This is deemed critical, as the eye suffers from lens clouding (cataract). Recent evidence resulted in recommendations to lower the threshold for exposure once more (Stewart et al. 2012). The geometric shape and the proximity of different anatomical structures render radiographic evaluation of the maxilla a rather complex task. The paired palatal bones are located directly adjacent to the maxilla at its dorsal end and, thus form the dorsal end of the hard palate. Even though they do not, in a strict anatomical sense, belong to the maxilla, in clinical terms they are often considered as being part of it. Maxillary and neighboring structures are a common locus for pathological conditions or dental procedures; hence, this anatomical region obviously represents a major focus for dental radiography.
New information on the giant Devonian lobe-finned fish Edenopteron from the New South Wales south coast
Published in Australian Journal of Earth Sciences, 2020
G. C. Young, R. L. Dunstone, P. J. Ollerenshaw, J. Lu, B. Crook
The lower jaw shows a partly exposed dentary fang (f.De, Figure 6c). Three opposing fangs at least 40 mm long and pointing ventrally must represent the dermopalatine and ectopterygoid of the upper dentition (f.Dpl, f.Ect). A row of small teeth, enmeshed with fangs of the lower jaw, is probably a portion of the upper marginal jaw bone (maxilla). The opposite (left) jaw is poorly exposed, but the actual jaw symphysis is well displayed on the lower blocks (V3481e, g; see Figure 7). The palate shows the vomers (Vo) with four fangs projecting into the rock, behind which is the parasphenoid (Psp) and accessory vomers (ac.Vo), their posterior edges lost in a fracture (Figure 6c). The post-parietal shield (PPSh, Figure 6a) is preserved approximately in the correct position relative to the palate. A clear midline suture separates radiating bone striations defining ossification centres for both post-parietals, incomplete supratemporals, and the left tabular (PPa, ST, Ta, Figure 6c). The posterior skull edge is obscured by rock matrix, but the total length was about 105 mm, giving the parietal shield about 1.7 times the length of the post-parietal shield, as in the holotype diagnosis of Young et al. (2013). Presumed median and lateral extrascapulars are displaced behind the skull (Esc.m, Esc.l, Figure 6c).