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Additive manufacturing in the craniofacial area
Published in Ali Khademhosseini, Gulden Camci-Unal, 3D Bioprinting in Regenerative Engineering, 2018
Cedryck Vaquette, Kelly McGowan, Saso Ivanovski
Dental implant therapy is indicated to increase chewing comfort [15,16], to replace strategically important missing teeth [17], or to provide an alternative means of supporting a dental prosthesis where natural tooth and existing satisfactory restorations would otherwise be subjected to invasive preparation procedures [18,19]. Implants can be used to support a single tooth crown, a bridge, or fixed and removable full arch prosthesis, which makes them a valuable addition to the dental clinician’s armamentarium. Safe and predictable implant placement requires an adequate volume of healthy bone, the availability of which must be carefully assessed through both clinical examination and three-dimensional (3D) radiography before commencing treatment [20]. The close proximity of the maxillary sinus and nasal cavity in the maxilla and the position of the inferior alveolar nerve within the mandible can be significant anatomical limitations to ideal implant placement and can act to limit the bone height available for implant placement following alveolar ridge resorption.
Computer-Aided Diagnosis with Dental Images
Published in de Azevedo-Marques Paulo Mazzoncini, Mencattini Arianna, Salmeri Marcello, Rangayyan Rangaraj M., Medical Image Analysis and Informatics: Computer-Aided Diagnosis and Therapy, 2018
Chisako Muramatsu, Takeshi Hara, Tatsuro Hayashi, Akitoshi Katsumata, Hiroshi Fujita
DPRs are the most widespread examination in dental clinics in developed countries. More than 17 and 10 million DPRs are taken annually in the United States and Japan, respectively [24, 25]. As shown in Figure 5.2, DPR is obtained by a pair of x-ray tube and detector rotating around an examinee. A DPR has a wide coverage depicting not only the upper and lower teeth, but also other structures around the mouth and neck, such as the maxilla, mandible, temporomandibular joint, maxillary sinus, and cervical vertebrae, as shown in Figure 5.3. A DPR is a kind of tomography; thus, the image is blurry compared to intraoral radiographs and has a small magnification effect. However, it allows the examination of the whole dental region, as well as the extra-dental regions, which have been attracting the attention of researchers in recent years.
Dental Radiography
Published in Paolo Russo, Handbook of X-ray Imaging, 2017
Obviously the main targets of intraoral radiography are the teeth. Intraoral radiographs aim at reproducing the tooth crowns (bitewing radiographs), the marginal alveolar bone, or, very commonly, the roots of the teeth (periapical radiographs) under investigation. In addition, intraoral radiography comprises occlusal projections. The anatomical targets of the latter in the case of maxillary occlusal radiography are the anterior hard palate, as well as anterior parts of the nasal cavity and the maxillary sinus. In some instances, also, the posterior parts of the hard palate are investigated with this type of radiograph. Mandibular occlusal radiography images the floor of the mouth as well as the anterior portion (and sometimes also the posterior portion) of the mandible in an axial direction.
Oral health of the prehistoric Rima Rau cave burials, Atiu, Cook Islands
Published in Journal of the Royal Society of New Zealand, 2020
Angela L. Clark, Christina Stantis, Hallie R. Buckley, Nancy Tayles
The sample includes 918 alveoli (with and without teeth in situ) in addition to the 366 teeth. Table 4 summarises the prevalence of the three oral indicators associated with dental infection. Of 341 teeth for which carious lesions could be recorded, 12.6% were carious. Caries are significantly more prevalent on molars than on other tooth types (Table 4). Mandibular teeth had a higher frequency of caries compared with maxillary teeth, but this difference is not statistically significant. Caries were significantly more frequent on the root surfaces compared with the crown surfaces. The occlusal crown surface had a significantly higher frequency of caries than any other crown surface. No significant differences in caries rates were observed for the different root surfaces. Periapical cavities were uncommon, with only 15 observed (1.9%). Despite the infrequency of such lesions, the periapical cavity for a young adult female was notably severe. As observed in Figure 2, the pathology can be identified by osteoblastic and osteoclastic activity, consistent with a bony response to an infection affecting the anterior right maxilla with lesions penetrating the maxillary sinus. Antemortem tooth loss (AMTL) occurred for 9.0% of teeth. AMTL is significantly more frequent with partial remodelling than with full remodelling of the alveolus.
The influence of framework material on stress distribution in maxillary complete-arch fixed prostheses supported by four dental implants: a three-dimensional finite element analysis
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2021
Suleyman Cagatay Dayan, Onur Geckili
A 3D finite-element model was constructed from a tomographic image of a patient with an atrophic maxilla and moderate maxillary sinus pneumatization. The local ethics committee of Istanbul University, Medical Faculty (Protocol No. 2018/85), approved the study protocol. Volumetric data were reconstructed in 0.2-mm slices and exported to 3D-Doctor (Able Software Corp., MA, USA) in DICOM 3.0 format. Data were segmented according to Hounsfield values using interactive segmentation. Complex rendering was used to construct a 3D model, using simplification to render a smooth surface. The completed model was exported in STL format to VRMesh Studio (VirtualGrid Inc, WA, USA), dimensional and topographic arrangements were made about the 3D model.