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1.
J Appl Oral Sci ; 28: e20190103, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32049131

RESUMEN

OBJECTIVE: This study aimed to assess the association between tooth size and root canal morphology by using CBCT analysis. METHODOLOGY: In this retrospective study, tooth anatomic lengths (crown and root lengths, buccolingual and mesiodistal dimensions) of 384 patients were assessed and correlated with Vertucci's root canal morphology classification. Data was analyzed for gender-related differences using the independent sample t-test, ANOVA, and the Pearson's correlation for a possible relation between anatomic lengths and canal morphology. RESULTS: The maxillary first and second premolars showed a greater predilection for Type IV and II variants, respectively, while the mandibular first premolar showed a greater predilection for Type II canal system. The root canal system of the mandibular second premolar showed maximal diversity (47% Type I, 30% Type II, and 20% Type III). The dimensions were greater in men regardless of tooth type. The most significant relation (p<0.05) between the anatomic size and canal morphology was observed in the maxillary first premolars, followed by the mandibular canines (buccolingual dimension) and the lower second premolars (crown length). Negative correlations existed between the crown length and the patient's age for the anterior teeth and mandibular second premolar (r=-0.2, p<0.01). CONCLUSIONS: The most common canal formation for anterior teeth was the Type I. The anatomic lengths had the strongest influence on the canal configuration of the maxillary first premolar, with Type IV being the most common root canal system. The mandibular second premolars showed maximal diversity in the canal classification terms and had a significant correlation with their crown lengths. CLINICAL RELEVANCE: The complex relationship between the canal morphology and anatomic tooth sizes need meticulous awareness and recognition during endodontic procedures, in conjunction with the demographic variabilities.


Asunto(s)
Tomografía Computarizada de Haz Cónico/métodos , Cavidad Pulpar/anatomía & histología , Diente/anatomía & histología , Adulto , Anciano , Análisis de Varianza , Cavidad Pulpar/diagnóstico por imagen , Femenino , Humanos , Masculino , Mandíbula/anatomía & histología , Mandíbula/diagnóstico por imagen , Maxilar/anatomía & histología , Maxilar/diagnóstico por imagen , Persona de Mediana Edad , Odontometría/métodos , Valores de Referencia , Estudios Retrospectivos , Factores Sexuales , Diente/diagnóstico por imagen , Estados Unidos
2.
J Appl Oral Sci ; 28: e20190148, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32049133

RESUMEN

OBJECTIVE: The site of the sinus tract depends on the rate of resistance against abscess exudate drainage, bone morphology, and distance from the root apex to the outer cortical bone. To assess apical bone thickness in buccal and palatal/lingual aspects of maxillary and mandibular teeth, using a high-resolution cone-beam computed tomography (CBCT) system. METHODOLOGY: In total, 422 CBCT examinations were included in the study, resulting in a sample of 1400 teeth. The scans were acquired by PreXion 3D, with a high-resolution protocol. The bone thickness was taken as the distance between the center of the apical foramen and the buccal and lingual/palatal cortical bone. The quantitative variables were expressed as mean values±standard deviation. The independent samples were analyzed using the t-test or the Mann-Whitney test (p<0.05). RESULTS: The lowest mean value of bone thickness was observed in the buccal cortical bone of the upper canines (1.49 mm±0.86) and in the upper central incisors (1.59 mm±0.67). In premolar teeth, the lowest values were found in the buccal cortical bone of upper first premolars (1.13 mm±0.68). In the posterior teeth, the lowest values were found in the buccal cortical bone of upper first molars (1.98 mm±1.33). In the lower second molar region, the buccal cortical bone (8.36 mm±1.84) was thicker than the lingual cortical bone (2.95 mm±1.16) (p<0.05). CONCLUSIONS: The lowest mean values of bone thickness are in the buccal cortical bone of the maxillary teeth. In the mandible, bone thickness is thinner in the buccal bone around the anterior and premolar teeth, and in the lingual aspect of mandibular molars. All these anatomic characteristics could make the occurrence of the sinus tract more susceptible in these specific regions of the maxillary and mandibular alveolar bone.


Asunto(s)
Tomografía Computarizada de Haz Cónico/métodos , Mandíbula/anatomía & histología , Maxilar/anatomía & histología , Diente/anatomía & histología , Adulto , Femenino , Humanos , Masculino , Mandíbula/diagnóstico por imagen , Maxilar/diagnóstico por imagen , Odontometría/métodos , Valores de Referencia , Estadísticas no Paramétricas , Diente/diagnóstico por imagen
3.
J Appl Oral Sci ; 28: e20190435, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32049138

RESUMEN

OBJECTIVE: To quantify the bone volume that can be safely withdrawn from 3 donor sites: (1) the mandibular symphysis, (2) the oblique mandibular line and (3) the skullcap. METHODOLOGY: For the symphysis, 200 tomographic exams were evaluated by the extension of the anterior loop of mental foramen, by the nerve, by the distance of the foramens, by the distance between the vestibular cortical and the lingual plates and by the distance between the apexes, or lower anterior teeth, and the mandibular base, using the "distance" tool of the I-CAT Vision, in the panoramic and parasagittal reformations. For the oblique line, 70 TCFC exams were analyzed retrospectively in panoramic and parasagittal reformations, evaluating the thickness of the vestibular cortical and the distance between the cortical and the mandibular canal. For the cranial bone, a hexagonal donor site located in parietal area was considered. RESULTS: The average dimensions of the bone blocks that can be safely removed from the region of the mandibular symphysis are: 32.27 mm in length, 4.87 mm in height and 4 mm in thickness, providing a volume of 628.61 mm3 available for grafting. In the oblique line, the available bone volume for grafting was 859.61 mm3. In the region of the cranial vault, multiplying the average bone thickness by the area of the hexagon, an average volume of 2,499 mm3 was obtained. CONCLUSIONS: Comparing the donor sites, the bone availability in the cranial vault is 3 times greater than in the mandibular posterior region, and at least 2 times greater than in the mandibular symphysis.


Asunto(s)
Trasplante Óseo/métodos , Tomografía Computarizada de Haz Cónico/métodos , Mandíbula/trasplante , Cráneo/trasplante , Sitio Donante de Trasplante , Adolescente , Adulto , Anciano , Puntos Anatómicos de Referencia , Hueso Cortical/diagnóstico por imagen , Hueso Cortical/trasplante , Femenino , Humanos , Masculino , Mandíbula/diagnóstico por imagen , Ilustración Médica , Persona de Mediana Edad , Estudios Retrospectivos , Cráneo/diagnóstico por imagen , Sitio Donante de Trasplante/diagnóstico por imagen , Adulto Joven
4.
Int J Oral Sci ; 12(1): 4, 2020 01 14.
Artículo en Inglés | MEDLINE | ID: mdl-31932579

RESUMEN

The morphology of the alveolar bone at the maxillary anterior teeth in periodontitis patients was evaluated by cone-beam computed tomography (CBCT) to investigate the distribution of alveolar defects and provide guidance for clinical practice. Ninety periodontitis patients and 30 periodontally healthy individuals were selected to determine the morphology of the alveolar bone at the maxillary anterior teeth according to the degree of bone loss, tooth type, sex and age. The differences in the dimensions between periodontitis patients and healthy individuals were compared, and the distribution of alveolar bone defects was analyzed. A classification system was established regarding the sagittal positions and angulations of the teeth. The buccal residual bone was thicker and the lingual bone was thinner in the periodontitis patients than in the periodontally healthy individuals, and there were differences between the different tooth types, sexes and age subgroups. The buccal undercut was close to the alveolar ridge, while fenestration was reduced and the apical bone height was higher in periodontitis patients than in periodontally healthy individuals. The apical bone height increased with the aggravation of bone loss and age. The proportions of different sagittal positions changed with the aggravation of bone loss. Moreover, the teeth moved more buccally regarding the positions of the maxillary anterior teeth. The morphology of the alveolar bone at the maxillary anterior teeth differed between periodontitis patients and healthy individuals, and the differences were related to the degree of bone loss, tooth type, sex and age.


Asunto(s)
Proceso Alveolar/diagnóstico por imagen , Tomografía Computarizada de Haz Cónico/métodos , Incisivo/diagnóstico por imagen , Maxilar/diagnóstico por imagen , Periodontitis/diagnóstico por imagen , Adulto , Proceso Alveolar/anatomía & histología , Femenino , Humanos , Incisivo/anatomía & histología , Masculino , Maxilar/anatomía & histología , Estudios Retrospectivos , Ápice del Diente/anatomía & histología , Ápice del Diente/diagnóstico por imagen , Cuello del Diente/anatomía & histología , Cuello del Diente/diagnóstico por imagen
5.
Int J Radiat Oncol Biol Phys ; 106(3): 612-620, 2020 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-31738948

RESUMEN

PURPOSE: The cone-beam computed tomography (CBCT)-guided small animal radiation research platform (SARRP) has provided unique opportunities to test radiobiologic hypotheses. However, CBCT is less adept to localize soft tissue targets growing in a low imaging contrast environment. Three-dimensional bioluminescence tomography (BLT) provides strong image contrast and thus offers an attractive solution. We introduced a novel and efficient BLT-guided conformal radiation therapy and demonstrated it in an orthotopic glioblastoma (GBM) model. METHODS AND MATERIALS: A multispectral BLT system was integrated with SARRP for radiation therapy (RT) guidance. GBM growth curve was first established by contrast CBCT/magnetic resonance imaging (MRI) to derive equivalent sphere as approximated gross target volume (aGTV). For BLT, mice were subject to multispectral bioluminescence imaging, followed by SARRP CBCT imaging and optical reconstruction. The CBCT image was acquired to generate anatomic mesh for the reconstruction and RT planning. To ensure high accuracy of the BLT-reconstructed center of mass (CoM) for target localization, we optimized the optical absorption coefficients µa by minimizing the distance between the CoMs of BLT reconstruction and contrast CBCT/MRI-delineated GBM volume. The aGTV combined with the uncertainties of BLT CoM localization and target volume determination was used to generate estimated target volume (ETV). For conformal irradiation procedure, the GBM was first localized by the predetermined ETV centered at BLT-reconstructed CoM, followed by SARRP radiation. The irradiation accuracy was qualitatively confirmed by pathologic staining. RESULTS: Deviation between CoMs of BLT reconstruction and contrast CBCT/MRI-imaged GBM is approximately 1 mm. Our derived ETV centered at BLT-reconstructed CoM covers >95% of the tumor volume. Using the second-week GBM as an example, the ETV-based BLT-guided irradiation can cover 95.4% ± 4.7% tumor volume at prescribed dose. The pathologic staining demonstrated the BLT-guided irradiated area overlapped well with the GBM location. CONCLUSIONS: The BLT-guided RT enables 3-dimensional conformal radiation for important orthotopic tumor models, which provides investigators a new preclinical research capability.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Mediciones Luminiscentes , Imagen Multimodal/métodos , Radioterapia Conformacional , Radioterapia Guiada por Imagen , Animales , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/radioterapia , Tomografía Computarizada de Haz Cónico/métodos , Medios de Contraste , Glioblastoma/diagnóstico por imagen , Glioblastoma/patología , Glioblastoma/radioterapia , Procesamiento de Imagen Asistida por Computador , Imagen Tridimensional/métodos , Mediciones Luminiscentes/instrumentación , Mediciones Luminiscentes/métodos , Imagen por Resonancia Magnética/métodos , Ratones , Ratones Endogámicos C57BL , Modelos Animales , Radioterapia Conformacional/instrumentación , Radioterapia Conformacional/métodos , Radioterapia Guiada por Imagen/instrumentación , Radioterapia Guiada por Imagen/métodos , Carga Tumoral
6.
Int J Radiat Oncol Biol Phys ; 106(1): 185-193, 2020 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-31580928

RESUMEN

PURPOSE: Recurrent or previously irradiated head and neck cancers (HNC) are therapeutically challenging and may benefit from high-dose, highly accurate radiation techniques, such as stereotactic ablative radiation therapy (SABR). Here, we compare set-up and positioning accuracy across HNC subsites to further optimize the treatment process and planning target volume (PTV) margin recommendations for head and neck SABR. METHODS AND MATERIALS: We prospectively collected data on 405 treatment fractions across 79 patients treated with SABR for recurrent/previously irradiated HNC. First, interfractional error was determined by comparing ExacTrac x-ray to the treatment plan. Patients were then shifted and residual error was measured with repeat x-ray. Next, cone beam computed tomography (CBCT) was compared with ExacTrac for positioning agreement, and final shifts were applied. Lastly, intrafractional error was measured with x-ray before each arc. Results were stratified by treatment site into skull base, neck/parotid, and mucosal. RESULTS: Most patients (66.7%) were treated to 45 Gy in 5 fractions (range, 21-47.5 Gy in 3-5 fractions). The initial mean ± standard deviation interfractional errors were -0.2 ± 1.4 mm (anteroposterior), 0.2 ± 1.8 mm (craniocaudal), and -0.1 ± 1.7 mm (left-right). Interfractional 3-dimensional vector error was 2.48 ± 1.44, with skull base significantly lower than other sites (2.22 vs 2.77; P = .0016). All interfractional errors were corrected to within 1.3 mm and 1.8°. CBCT agreed with ExacTrac to within 3.6 mm and 3.4°. CBCT disagreements and intrafractional errors of >1 mm or >1° occurred at significantly lower rates in skull base sites (CBCT: 16.4% vs 50.0% neck, 52.0% mucosal, P < .0001; intrafractional: 22.0% vs 48.7% all others, P < .0001). Final PTVs were 1.5 mm (skull base), 2.0 mm (neck/parotid), and 1.8 mm (mucosal). CONCLUSIONS: Head and neck SABR PTV margins should be optimized by target site. PTV margins of 1.5 to 2 mm may be sufficient in the skull base, whereas 2 to 2.5 mm may be necessary for neck and mucosal targets. When using ExacTrac, skull base sites show significantly fewer uncertainties throughout the treatment process, but neck/mucosal targets may require the addition of CBCT to account for positioning errors and internal organ motion.


Asunto(s)
Neoplasias de Cabeza y Cuello/radioterapia , Recurrencia Local de Neoplasia/radioterapia , Radiocirugia/métodos , Errores de Configuración en Radioterapia , Anciano , Tomografía Computarizada de Haz Cónico/métodos , Fraccionamiento de la Dosis de Radiación , Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Neoplasias de Cabeza y Cuello/patología , Humanos , Inmovilización/métodos , Persona de Mediana Edad , Recurrencia Local de Neoplasia/diagnóstico por imagen , Recurrencia Local de Neoplasia/patología , Neoplasias de la Parótida/diagnóstico por imagen , Neoplasias de la Parótida/radioterapia , Posicionamiento del Paciente , Estudios Prospectivos , Mejoramiento de la Calidad , Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia Guiada por Imagen/métodos , Reirradiación/métodos , Neoplasias de la Base del Cráneo/diagnóstico por imagen , Neoplasias de la Base del Cráneo/radioterapia
7.
Br J Radiol ; 93(1105): 20180989, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31742428

RESUMEN

OBJECTIVE: To assess the rates of fractures and ligament injuries in patients with an acute ankle injury and a normal radiographic examination, and to consider the most appropriate examination protocol. METHODS: Patients with an acute ankle injury who presented to the John Radcliffe Hospital Emergency Department with a normal radiographic examination were eligible for the study. They were invited to receive a cone beam CT and ultrasound examination at a local radiology department within 5 days of their ankle injury. RESULTS: Of the 100 patients recruited to the study, 19 patients were found to have major fractures and 42 patients had small avulsion fractures. Additionally, 42 patients had ankle effusions and there were a large number of soft tissue injuries. There were 83 acute injuries of the anterior talofibular ligament, 19 of the anterior tibiofibular ligaments, 26 of the calcaneofibular ligament, 39 of the deltoid ligament complex, 21 of the talonavicular ligament, 14 of the spring ligament and 3 of the calcaneocuboid ligament. CONCLUSION: Conventional radiographic examination misses significant fractures of the foot and ankle and the presence of an ankle effusion does not relate to the severity of injury. Ultrasound is a useful imaging technique that can supplement clinical practice, but it is unlikely to replace current protocols alone. Cone beam CT is an appropriate alternative to plain radiography, being more sensitive in detecting fractures and delivering a similar dose of radiation. However, neither CT or ultrasound examination can detect all avulsion fractures. Simple anterior process fractures of the calcaneus are associated with talonavicular ligament injuries and the medial ligaments are injured in almost 50% of cases when there is a lateral ligament injury. ADVANCES IN KNOWLEDGE: Fractures in the foot and ankle are detected more precisely with cone beam CT compared to radiographs. Cone beam CT delivers similar doses of to conventional radiographs which is around 10% of that resulting from conventional CT. Ultrasound examination is an effective assessment tool to detect ligamentous injuries. The absence of an ankle effusion does not exclude a major fracture.


Asunto(s)
Traumatismos del Tobillo/diagnóstico por imagen , Tomografía Computarizada de Haz Cónico/métodos , Fracturas Óseas/diagnóstico por imagen , Ligamentos Articulares/diagnóstico por imagen , Ligamentos Articulares/lesiones , Traumatismos de los Tejidos Blandos/diagnóstico por imagen , Ultrasonografía/métodos , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
8.
Gen Dent ; 68(1): 66-71, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31859666

RESUMEN

Knowledge of the anatomical relationships between the maxillary sinus (MS) and posterior teeth is important to prevent complications when endodontic or oral surgical procedures are performed. The aim of this study was to evaluate the relationships between the root apices of maxillary posterior teeth and the MS floor. Three oral radiologists evaluated 851 posterior teeth (1969 roots) imaged with cone beam computed tomography. The roots were analyzed individually in parasagittal sections, on which the most superior point of the apex was observed. A qualitative evaluation was performed, and each root was assigned a proximity score: 1, root invaginating the MS; 2, root in close contact with the MS floor; 3, root with no relationship with the MS; and 4, root with a measurable proximity to the MS. For roots classified as score 4, the distance to the MS floor was measured (quantitative analysis). Student t tests, 1-way analysis of variance, and simple linear regression analysis were performed (P < 0.05). The qualitative analysis revealed that the mesiobuccal root of the second molar had a pronounced proximity to the MS. The quantitative analysis revealed no differences in distance to the MS between right and left posterior teeth or between the different roots of the same tooth. In relation to the MS, the second molar was positioned closest, followed by the first molar, second premolar, and first premolar. Except for the comparison between mean distances of the second premolar and first molar (P = 0.11), the differences between groups of teeth were statistically significant (P < 0.05). Simple linear regression analysis showed that the more posterior the tooth was in relation to the midline, the shorter the mean distance from the root apex to the MS floor (P < 0.05). The mesiobuccal roots of second molars were closest to the MS. Second molars exhibited the shortest distances between their root apices and the MS and the greatest number of roots that were invaginating or in close contact with the MS. Therefore, second molars require special attention when endodontic or oral surgical approaches involve those regions.


Asunto(s)
Tomografía Computarizada de Haz Cónico/métodos , Maxilar , Seno Maxilar , Humanos , Procesamiento de Imagen Asistida por Computador , Maxilar/anatomía & histología , Seno Maxilar/anatomía & histología , Seno Maxilar/diagnóstico por imagen , Diente Molar/anatomía & histología , Diente Molar/diagnóstico por imagen , Raíz del Diente/anatomía & histología , Raíz del Diente/diagnóstico por imagen
9.
Eur Radiol ; 30(1): 163-174, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31359127

RESUMEN

OBJECTIVES: To assess the impact of recently developed respiratory motion correction software on contrast-enhanced cone beam CT angiography (CBCT-a) for intraprocedural image guidance during intra-arterial liver-directed therapy. METHODS: From 2015 to 2017, two groups of patients who underwent intra-arterial liver-directed therapy with (breathing, n = 30) or without (still, n = 30) significant respiratory motion artifacts were retrospectively included. All CBCT-a were processed with and without dedicated respiratory motion correction software. Four readers independently assessed the following in both reconstructions (motion correction ON and OFF): (1) overall image quality on a 0-to-5 point scale, and (2) presence of relevant peri-procedural information on tumor and vasculature (overall vessel geometry, visibility of extrahepatic vessels, target tumor conspicuity, visibility of tumor feeders). RESULTS: Motion correction increased the average image quality in the breathing group from 2.0 ± 0.9 to 2.9 ± 1.0 (p < 0.01). The visibility of vessel geometry, extrahepatic vessels, and tumor feeders was significantly improved for all readers, and tumor conspicuity was improved for three readers. The average image quality was not significantly different between reconstructions in the still group (motion correction ON and OFF), for any of the readers (4.0 ± 0.6 vs 4.2 ± 0.6; p = 0.12). There was no change in the visibility of vessel geometry, extrahepatic vessels, tumor feeders, or tumor conspicuity for the four readers using the respiratory motion correction software in this group. CONCLUSIONS: Using the dedicated respiratory motion correction software during intra-arterial liver-directed procedures increases the visualization of relevant peri-procedural information and image quality in CBCT-a corrupted by respiratory motion artifacts without affecting these elements in still CBCT-a. KEY POINTS: • The use of respiratory motion correction software could reduce the need for cone beam CT angiography acquisition retake. • Motion correction software significantly increases the visibility of vessel geometry, extrahepatic vessels, and tumor feeders, as well as tumor conspicuity in cone beam CT angiography corrupted by respiratory motion artifacts. • The use of respiratory motion correction software on cone beam CT angiography uncorrupted by respiratory motion artifact does not result in decreased image quality.


Asunto(s)
Artefactos , Angiografía por Tomografía Computarizada/métodos , Tomografía Computarizada de Haz Cónico/métodos , Neoplasias Hepáticas , Intensificación de Imagen Radiográfica/métodos , Anciano , Anciano de 80 o más Años , Algoritmos , Quimioembolización Terapéutica/métodos , Femenino , Humanos , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/terapia , Persona de Mediana Edad , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Respiración , Estudios Retrospectivos , Programas Informáticos
10.
Urologiia ; (5): 53-58, 2019 Dec.
Artículo en Ruso | MEDLINE | ID: mdl-31808633

RESUMEN

AIM: The aim of this study was to determine the possibilities of volumetric dynamic voiding multispiral computed cystourethrography (VDMMCT) for assessment of the lower urinary tract during voiding. MATERIALS AND METHODS: VDMMCT was performed in a series of 22 patients with various urethral pathologies using 320 detector rows (640 unique slices; row width 0,5 mm). This method allows to cover the scan area of 16 cm per one rotation of the X-ray tube. In all patients, the cross-sectional area of the various urethral parts was estimated and the urinary bladder volume and average urine flow rate during all voiding phases were calculated. RESULTS: VDMMCT was performed for dynamic evaluation of bladder volumes changes and analyzing a passage of contrasted urine throughout the urethra. The average volume of the urinary bladder was 356.3+/-179.9 ml, while the voiding volume was 299.5+/-154.8 ml. The average pre- and postoperative urine flow rate was 4.1+/-1.1 ml/s and 7.9+/-5.1 ml/s, respectively. The maximum urine flow rate was 19 ml/s. The average urethral diameter according to the VDMMCT after urethroplasty was 7.6+/-2.1 mm. The minimum length of urethral strictures was 17 mm, while the maximum length was 32 mm. CONCLUSION: Our results demonstrate the efficiency of the VDMMCT for assessing of the urethra throughout its length. VDMMCT can multidimensionally and dynamically represent the change of the bladder volume and the urine flow rate.


Asunto(s)
Tomografía Computarizada de Haz Cónico/métodos , Estrechez Uretral/diagnóstico , Urografía/métodos , Humanos , Masculino , Uretra , Estrechez Uretral/diagnóstico por imagen , Vejiga Urinaria , Micción
11.
J Craniofac Surg ; 30(8): 2565-2569, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31689732

RESUMEN

This clinical report presents the outcomes of segmental corticotomy-assisted orthodontic treatment in a class III patient. A 13.5-year-old female patient presented with class III anomaly and a thin alveolus in the mandibular anterior region. After the alignment of the mandibular incisors, segmental corticotomy with platelet-rich fibrin (PRF) was performed in the mandibular incisor area to facilitate incisor retraction to ensure periodontal support after the changes in the inclination of the teeth. Lateral cephalograms were taken at the beginning (T0), precorticotomy (T1), at the end of the treatment (T2), and 2 years after the treatment (T3). Cone-beam computed tomography (CBCT) records were collected at the T1, T2, and T3 periods to evaluate the bone structures. The measurements included the inclination and the position of the mandibular incisors, symphysis width, symphysis height, B-B' width, cervical alveolar width, the vertical alveolar bone level on the labial and the lingual sides, and the amount of labial and lingual bone at the apex in the mandibular central incisor and canine areas.The class I molar and canine relationship was achieved in this borderline case. The amount of labial bone at the root apex and the B-B' width increased. A vertical alveolar bone gain was observed. The facial profile was improved significantly. The treatment outcome was stable at the 2-year follow-up. The segmental anterior mandibular corticotomy provided an effective correcting inclination of the mandibular teeth with the use of class III elastics. This technique ensured the maintenance of a sufficient amount of labial bone with no periodontal side effects.


Asunto(s)
Maloclusión de Angle Clase III/cirugía , Fibrina Rica en Plaquetas , Adolescente , Tomografía Computarizada de Haz Cónico/métodos , Femenino , Humanos , Incisivo , Maloclusión de Angle Clase III/diagnóstico por imagen , Mandíbula
12.
Medicine (Baltimore) ; 98(48): e18166, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31770264

RESUMEN

RATIONALE: Hepatectomy is a treatment to increase survival and curability of patients with intrahepatic lesions or malignant tumors. However, posthepatectomy liver failure (PHLF) can occur. This case is a patient showing acute mental change in postanesthetic care unit (PACU) as an uncommon symptom of PHLF after extended right hepatectomy. PATIENT CONCERNS: A 68-year-old male patient was admitted for surgery of Klatskin tumor. He had hypertension and atrial fibrillation. His model for end-stage liver disease score was 16 pts. His serum bilirubin and ammonia levels were 4.75 mg/dL and 132.8 mcg/dL, respectively. Other laboratory data were nonspecific. He underwent extended right hepatic lobectomy including segments IV-VIII for 9 hours. Weight of liver specimen was 1028 g which was about 58% of total liver volume based on computed tomographic volumetry. The patient was extubated and moved to the PACU with stable vital sign and regular self-breathing. He could obey verbal commands. Fifteen minutes after admission to the PACU, the patient showed abruptly decreasing mental status and self-breathing. DIAGNOSES: Brain computed tomography, blood culture, and sputum culture were performed to diagnose brain lesions and sepsis for evaluating the sudden onset comatous mental status. Results showed nonspecific finding. INTERVENTIONS: He was intubated for securing airway and applying ventilatory care. The patient was moved to the intensive care unit. He received intensive conservative therapy including continuous renal replacement therapy and broad-spectrum antibiotics. OUTCOMES: The patient's condition was worsened. He expired on postoperative day 3. LESSONS: Acute mental change is uncommon and rare as initial symptoms of PHLF. Therefore, clinician may overlook the diagnosis of PHLF in patients with acute mental change after hepatectomy. Thus, clinician should plan an aggressive treatment for PHLF including liver transplantation by recognizing any suspicious symptom, although such symptom is rare.


Asunto(s)
Neoplasias de los Conductos Biliares/cirugía , Hepatectomía , Encefalopatía Hepática , Tumor de Klatskin/cirugía , Fallo Hepático , Hígado , Complicaciones Posoperatorias , Anciano , Neoplasias de los Conductos Biliares/patología , Tomografía Computarizada de Haz Cónico/métodos , Tratamiento Conservador/métodos , Resultado Fatal , Hepatectomía/efectos adversos , Hepatectomía/métodos , Encefalopatía Hepática/diagnóstico , Encefalopatía Hepática/etiología , Encefalopatía Hepática/fisiopatología , Humanos , Tumor de Klatskin/patología , Hígado/diagnóstico por imagen , Hígado/patología , Hígado/cirugía , Fallo Hepático/diagnóstico , Fallo Hepático/etiología , Fallo Hepático/psicología , Pruebas de Función Hepática/métodos , Masculino , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/fisiopatología , Complicaciones Posoperatorias/psicología
13.
Niger J Clin Pract ; 22(11): 1611-1616, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31719285

RESUMEN

Aims: To investigate the root canal's anatomy, gender differences, and bilateral symmetry of permanent mandibular incisors using cone-beam computed tomography (CBCT). Materials and Methods: A total of 208 patients with 822 well-developed mandibular incisors were evaluated. CBCT images were retrieved from the database of patients who received treatment in the College of Dentistry and Dental Clinics. The following parameters were evaluated using CBCT: (1) the number of roots; (2) the number of canals; (3) canal configuration according to Vertucci's classification; (4) differences between genders; and (5) bilateral symmetry. Results: Two canals appeared in 26.3% of mandibular central incisors, 30.8% of lateral incisors, and 28.6% of all the 822 mandibular incisors. In the teeth with two canals, Type III configuration was dominant. There were no statistically significant differences found between the central and lateral incisors (P = 0.449). There were gender differences in central incisors, while lateral incisors showed none. Slight bilateral asymmetries appeared in central and lateral incisors in relation to some canals and canals configurations. Conclusion: CBCT can be of great use in locating the second canal and determining canal configuration in mandibular incisors. Knowledge of bilateral asymmetry can be of clinical significance when the clinician is treating contralateral teeth in the same patient.


Asunto(s)
Tomografía Computarizada de Haz Cónico/métodos , Cavidad Pulpar/diagnóstico por imagen , Incisivo/diagnóstico por imagen , Mandíbula/diagnóstico por imagen , Raíz del Diente/diagnóstico por imagen , Adulto , Cavidad Pulpar/anatomía & histología , Femenino , Humanos , Incisivo/anatomía & histología , Masculino , Mandíbula/anatomía & histología , Persona de Mediana Edad , Arabia Saudita , Factores Sexuales , Raíz del Diente/anatomía & histología
14.
Am J Orthod Dentofacial Orthop ; 156(4): 493-501, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31582121

RESUMEN

INTRODUCTION: The purpose of this research was to evaluate dental compensation in facial asymmetry and its correlation with skeletal variables using cone-beam computed tomography. METHODS: Sixty adult patients were retrospectively divided into asymmetry (mean age, 21.8 ± 5.4 years) and symmetry groups (mean age, 28.1 ± 4.1 years); both groups comprised 30 patients. Independent and paired t tests were used for comparisons between the asymmetry and symmetry groups and between deviated (Dv) and nondeviated (NDv) sides of the asymmetry group, respectively. Pearson correlation between dental and skeletal variables was performed. RESULTS: The mean value of menton deviation was 9.4 mm in the asymmetry group. Compared with the symmetry group, the direction and amount of dental compensation of the asymmetry group were as follows: 2.5-mm extrusion of the maxillary first molar (UM6) at NDv (P <0.05); 1.8-mm higher position of the mandibular canine (LC) from the mandibular horizontal plane using mental foramen (MHP_mf) at NDv (P <0.05); 6°-more buccoversion of UM6 at Dv; 3.7°-more linguoversion of UM6 at NDv; 4.8°-more buccoversion of the maxillary canine (UC) at Dv; 4.9°-more buccoversion of the mandibular molar (LM6) at NDv; and 2.6°-more linguoversion of LC at Dv. Dental compensation correlated or marginally correlated with skeletal variables of the deviated mandible. CONCLUSIONS: Dental compensations, extrusion of the maxillary molars on the NDv, and buccal tipping of the maxillary teeth and lingual tipping of the mandibular teeth on the Dv, were observed. The mandibular body length was associated with linguoversion of the mandibular molars on the Dv. The ramal inclination was related to the extrusion of the maxillary molars on the NDv.


Asunto(s)
Cefalometría/métodos , Tomografía Computarizada de Haz Cónico/métodos , Asimetría Facial/diagnóstico por imagen , Maloclusión/diagnóstico por imagen , Diente Molar/diagnóstico por imagen , Adolescente , Adulto , Estética Dental , Asimetría Facial/fisiopatología , Femenino , Humanos , Imagen Tridimensional/métodos , Masculino , Maloclusión/fisiopatología , Persona de Mediana Edad , Diente Molar/fisiopatología , Estudios Retrospectivos
15.
Am J Orthod Dentofacial Orthop ; 156(4): 566-573, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31582128

RESUMEN

INTRODUCTION: Accurate root position is imperative for successful orthodontic treatment that is stable and functional. Current methods to monitor root position are either inaccurate or use relatively high levels of radiation. A method to generate an expected root position (ERP) setup has been reported to have the potential to accurately evaluate root position with minimal radiation. The purpose of this study was to determine the accuracy and reliability of the clinical decisions made on root position using the ERP setup. METHODS: This retrospective study included 10 subjects who had pretreatment and midtreatment cone-beam computed tomography (CBCT) scans and study models. An ERP setup was generated for all patients at midtreatment. Four examiners assessed both the CBCT scan and ERP setup and made clinical decisions regarding the root position with each method. Cohen's kappa was determined to assess intraoperator and intermethod reliability. Sensitivity, specificity, positive predictive value, and negative predictive value were calculated to determine the accuracy of the ERP setup. RESULTS: The kappa values for intraoperator reliability for both the CBCT scan and ERP setup fell within the 0.61-0.80 range. The kappa values for intermethod reliability between the CBCT scan and ERP setup fell within the 0.61-0.80 range for all tooth groups. The sensitivity of the ERP setup ranged from 0.72 to 0.90, specificity ranged from 0.89 to 0.97, positive predictive value ranged from 0.57 to 0.85, and negative predictive value ranged from 0.93 to 0.99. CONCLUSIONS: This study demonstrated that the ERP setup, when compared with the gold standard CBCT scan, was accurate and reliable in making clinical decisions regarding root position at midtreatment.


Asunto(s)
Toma de Decisiones Clínicas , Tomografía Computarizada de Haz Cónico/métodos , Imagen Tridimensional/métodos , Técnicas de Movimiento Dental , Raíz del Diente/anatomía & histología , Raíz del Diente/diagnóstico por imagen , Modelos Dentales , Humanos , Reproducibilidad de los Resultados , Estudios Retrospectivos , Sensibilidad y Especificidad
16.
Niger J Clin Pract ; 22(10): 1448-1456, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31607738

RESUMEN

Objective: The purpose of this study was to investigate a relationship between gingival tissue biotypes and arch form with Schneiderian membrane thickness, using limited cone beam computed tomography. Materials and Methods: A total of 90 subjects were selected. For each subject three parameters were assessed - gingival biotype - clinically by Probe transparency method as thin or thick and coded as 0 and 1, respectively, gingival thickness and Schneiderian membrane thickness in mm, arch form as square, oval, or tapered (radiographically by cone beam computed tomography images). Central incisors and first molars were assessed for gingival biotype and gingival thickness and Schneiderian membrane thickness was determined at 16. Numerical data were estimated for normal distribution. Analysis of Variance test was followed by Tukey honestly significant difference test and Pearson's correlation coefficient test for analysis. Results: Thin gingival biotype was found associated with the central incisors and thick gingival biotype with molars. Limited cone beam computed tomography scans evaluation revealed highest prevalence of square arch form followed by oval, and tapered. The average thickness of the Schneiderian membrane was 1.18 ± 0.43 mm on left side and 1.09 ± 0.41 mm on right side with a range of 0.50 - 2.00 mm. Mean Schneiderian membrane thickness was more in case of thick gingival biotype and with square arc form both on right and left sides. Conclusions: The Schneiderian membrane thickness was positively and highly associated with gingival biotype. The gingival biotype and arch form had significant effect on Schneiderian membrane thickness and can provide valuable clinical information on Schneiderian membrane thickness preoperatively for implant placement and sinus lift procedures.


Asunto(s)
Tomografía Computarizada de Haz Cónico/métodos , Implantes Dentales , Encía/diagnóstico por imagen , Mucosa Nasal/diagnóstico por imagen , Arco Dental/anatomía & histología , Arco Dental/diagnóstico por imagen , Femenino , Encía/anatomía & histología , Humanos , Masculino , Diente Molar , Adulto Joven
17.
Technol Cancer Res Treat ; 18: 1533033819873629, 2019 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-31551011

RESUMEN

In adaptive radiation therapy of head and neck cancer, any significant anatomical changes observed are used to adapt the treatment plan to maintain target coverage without elevating the risk of xerostomia. However, the additional resources required for adaptive radiation therapy pose a challenge for broad-based implementation. It is hypothesized that a change in transit fluence is associated with volumetric change in the vicinity of the target and therefore can be used as a decision support metric for adaptive radiation therapy. This was evaluated by comparing the fluence with volumetric changes in 12 patients. Transit fluence was measured by an in vivo portal dosimetry system. Weekly cone beam computed tomography was used to determine volume change in the rectangular region of interest from condyloid process to C6. The integrated transit fluence through the region of interest on the day of the cone beam computed tomography scan was calculated with the first treatment as the baseline. The correlation between fluence change and volume change was determined. A logistic regression model was also used to associate the 5% region of interest volume reduction replanning trigger point and the fluence change. The model was assessed by a chi-square test. The area under the receiver-operating characteristic curve was also determined. A total of 46 pairs of measurements were obtained. The correlation between fluence and volumetric changes was found to be -0.776 (P value <.001). The negative correlation is attributed to the increase in the photon fluence transport resulting from the volume reduction. The chi-square of the logistic regression was found to be 17.4 (P value <.001). The area under the receiver-operating characteristic curve was found to be 0.88. Results indicate the change in transit fluence, which can be measured without consuming clinical resources or requiring additional time in the treatment room, can be used as a decision support metric for adaptive therapy.


Asunto(s)
Sistemas de Apoyo a Decisiones Clínicas , Neoplasias de Cabeza y Cuello/radioterapia , Radiometría , Planificación de la Radioterapia Asistida por Computador , Algoritmos , Toma de Decisiones Clínicas , Tomografía Computarizada de Haz Cónico/métodos , Tomografía Computarizada de Haz Cónico/normas , Manejo de la Enfermedad , Neoplasias de Cabeza y Cuello/diagnóstico , Humanos , Curva ROC , Radiometría/métodos , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador/métodos , Resultado del Tratamiento
18.
J Craniofac Surg ; 30(7): 2094-2098, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31503128

RESUMEN

PURPOSE: The aim of this study was to measure the cortical bone thickness of the infrazygomatic crest area in individuals with unilateral cleft lip and palate using cone beam computed tomography for placement of miniplates used for bone anchored maxillary protraction. MATERIALS AND METHODS: CBCT scans were obtained from 31 non-syndromic UCLP children diagnosed with maxillary hypoplasia (17 males, 14 females, mean age: 11.9 years). 5 horizontal and 5 vertical reference planes were drawn at the infrazygomatic crest area. The cortical bone thickness at 25 intersection points on the cleft side and the non-cleft side was measured. RESULTS: The mean cortical bone thickness of the 25 measured points was 1.19 mm on the cleft side and 1.17 mm on the non-cleft side with no significant difference. The greatest cortical bone thickness was found to be at the most superior, posterior point (H+6, V+0), which was 1.49 mm on the cleft side and 1.47 mm on the non-cleft side. The thinnest mean cortical bone thickness was measured at the most inferior, anterior point (H-2, V-8), which was 0.94 mm on the cleft side and 0.95 mm on the non-cleft side. There was no significant difference between males and females.


Asunto(s)
Labio Leporino/diagnóstico por imagen , Fisura del Paladar/diagnóstico por imagen , Adolescente , Niño , Tomografía Computarizada de Haz Cónico/métodos , Hueso Cortical/diagnóstico por imagen , Femenino , Humanos , Imagen Tridimensional , Masculino
19.
Oral Maxillofac Surg Clin North Am ; 31(4): 539-547, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31563194

RESUMEN

Dynamic navigation (DN) has been used by many fields previously and recently applied to dental implant surgery. DN allows the implant surgeon to evaluate a patient, scan the patient, plan the implant position, and perform the implant surgery in the same day without the delay or cost of fabrication of a static surgical guide stent. The current DN workflow requires (1) cone-beam computed tomography with fiducials, (2) virtual implant planning, (3) calibration, and (4) implant placement in accordance to the 3-D image on the navigation screen. This technology allows for improved precision and accuracy in the placement of dental implants.


Asunto(s)
Tomografía Computarizada de Haz Cónico/métodos , Implantación Dental/métodos , Implantes Dentales , Cirugía Asistida por Computador , Diseño Asistido por Computador , Implantación Dental Endoósea , Humanos , Imagen Tridimensional , Planificación de Atención al Paciente
20.
Eur J Radiol ; 119: 108659, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31520930

RESUMEN

PURPOSE: To evaluate image quality (IQ) and radiation dose in cone-beam computed tomography (CBCT) of the ankle using a novel twin robotic X-ray system. METHOD: We examined 16 cadaveric ankles with standard-dose (FD) and low-dose (LD) protocols using the new system's CBCT mode. For comparison, we performed multi-slice CT imaging (MSCT) with a clinical protocol. Three radiologists assessed IQ, noise and artifacts in bone and soft tissue on a five-point Likert scale (1= poor IQ; strong noise or artifacts; 5= excellent IQ; minimal noise or artifacts). Volume CT dose indices (CTDIvol) were calculated for radiation dose comparison between CBCT and MSCT. RESULTS: Overall IQ was described as very good or excellent by reader 1/2/3 in 62.5/87.5/56.3% of LD, 87.5/87.5/81.3% of FD and 100/87.5/87.5% of MSCT studies. Readers agreed that IQ was better in MSCT than LD (R1/R2/R3; p ≤ 0.008), two also found advantages of MSCT over FD (R1/R3; p ≤ 0.034). Soft tissue noise and artifacts were stronger in FD (all p ≤ 0.002) and LD (all p ≤ 0.001). In bone, artifacts and noise were also more severe in LD (all p < 0.001) and FD (all p ≤ 0.003). CTDIvol for clinical MSCT scans without dose modulation (15.0 ± 0.0 mGy) were higher than for FD (5.3 ± 1.0 mGy) and LD studies (2.9 ± 0.6 mGy; both p < 0.001). CONCLUSIONS: Despite MSCT providing better overall IQ than the twin robotic X-ray system's CBCT mode, both cone-beam protocols offer very good IQ in most studies and are suitable for clinical ankle imaging. Standard-dose and especially low-dose CBCT studies deliver up to five times less radiation dose than MSCT imaging.


Asunto(s)
Articulación del Tobillo/diagnóstico por imagen , Tomografía Computarizada de Haz Cónico/normas , Dosis de Radiación , Robótica/normas , Artefactos , Cadáver , Tomografía Computarizada de Haz Cónico/instrumentación , Tomografía Computarizada de Haz Cónico/métodos , Diseño de Equipo , Humanos , Fantasmas de Imagen , Robótica/métodos , Relación Señal-Ruido , Tomógrafos Computarizados por Rayos X/normas , Rayos X
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