Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 6.194
Filtrar
1.
Medicine (Baltimore) ; 99(3): e18875, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32011513

RESUMEN

RATIONALE: In surgery of the lower jaw, the application of computer-assisted navigation is complicated and challenging due to the mobile nature of the mandible. In this study, we presented a computer-assisted navigation surgery for removal of the foreign body in the lower jaw with a mandible reference frame, basing on the strategy that the mandible is independent as an entity. PATIENT CONCERNS: A 41-year-old male patient, identified as having a broken fissure bur that displaced into the mandibular lingual soft tissue, was referred to our department. The fissure bur broke accidentally and then displaced into the soft tissue when the patient underwent extraction of the left mandibular impacted third molar. DIAGNOSIS: A metallic foreign body in the left lower jaw, confirmed by orthopantomography. INTERVENTIONS: A computer-assisted navigation surgery with a customized mandible reference frame. OUTCOMES: The broken bur was removed successfully. Satisfactory wound healing and mouth opening was achieved, without postoperative complications. LESSONS: Surgeons should be alert to the presence of broken bur in the lower jaw and avoid its displacement into deep facial space, and computer-assisted navigation with a mandible reference frame is recommended for removal of the foreign body in the lower jaw.


Asunto(s)
Cuerpos Extraños/cirugía , Mandíbula/cirugía , Cirugía Asistida por Computador , Adulto , Cuerpos Extraños/diagnóstico por imagen , Humanos , Masculino , Mandíbula/diagnóstico por imagen , Radiografía Panorámica
2.
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
3.
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
4.
J Appl Oral Sci ; 28: e20190393, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32049137

RESUMEN

OBJECTIVES: This study assessed the incidence and variability features of root canals system (RCS) and their ramifications according to Pucci & Reig (PR) (1944) and the American Association of Endodontists (AAE) (2017) by micro-computed tomography (µCT). METHODOLOGY: 500 representative extracted human teeth of each tooth group (n=50) (maxillary/mandibular central and lateral incisors, canines, first and second premolars and molars) were scanned by µCT with a resolution of 26.70 µm. The reconstructed cross-sections images and the visualization of the continuous slices in the transversal axis were performed using DataViewer software. RCS were classified according to Pucci & Reig (main canal, collateral canal, lateral canal, secondary canal, accessory canal, intercanal, recurrent canal) and AAE (main canal, accessory canal, lateral canal). The apical deltas were assessed for both classifications. The prevalence of apical deltas was evaluated using the Chi-squared test (p<0.05). RESULTS: According to PR, a higher incidence of lateral canals was observed in maxillary canines (10%), central incisors (8%) and first premolars (6%). Using AAE, the highest incidence of lateral canals was observed in the mandibular first premolars (85%), first and second molars (84%), lateral incisors (67%), canines (59%), and in maxillary first premolars (52%). Regarding accessory canals, the PR showed a frequency in 2% of the maxillary lateral incisors and maxillary and mandibular first premolars and 3% of mandibular first and second molars. On the other hand, the AAE showed the highest incidence of accessory canals in 86% of the maxillary first premolars, 71% in mandibular lateral incisors, 69% in mandibular first premolars, 65% in mandibular canines, and 56% in maxillary canines. The PR showed the lowest incidence of apical deltas for all dental groups when compared with AAE (p=0.004). Interestingly, distal canals in maxillary molars showed a significant discrepancy between classifications (p=0.027). CONCLUSIONS: µCT enabled accurately describing the RC system and related ramifications, adding to the PR and AAE classifications, with some discrepancies reported for maxillary molars. Clinical Relevance This µCT study enabled a thorough description of the variability among root canals and their ramifications, including clinically relevant details on the presence and location of lateral canals and accessories in all human tooth groups, beyond the currently existing classification systems.


Asunto(s)
Cavidad Pulpar/anatomía & histología , Microtomografía por Rayos X/métodos , Cavidad Pulpar/diagnóstico por imagen , Humanos , Imagen Tridimensional , Mandíbula/anatomía & histología , Mandíbula/diagnóstico por imagen , Maxilar/anatomía & histología , Maxilar/diagnóstico por imagen , Valores de Referencia , Estadísticas no Paramétricas , Ápice del Diente/anatomía & histología , Ápice del Diente/diagnóstico por imagen
5.
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
6.
Medicine (Baltimore) ; 99(2): e18069, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31914012

RESUMEN

This study aims to find and locate foramens exactly in maxilla and mandible in case of complications during surgeries.Computer topographic angiography (CTA) images of 120 cases were reviewed. The measurements were performed on coronal, sagittal and axial planes after the 3 dimension volume reconstruction. The distances among foramens, bony landmarks, teeth, and facial artery were all measured with the angles as adjustments.The incisive foramen (IF) was measured 20.55 ±â€Š2.81 mm to margo inferior of incisor, and 45.27 ±â€Š5.27 degree from the axial midline. The greater palatine foramen located 43.17 ±â€Š2.55 mm from the IF, while 21.08 ±â€Š3.75 degree from the midline in axial plane. The lesser palatine foramina located 44.56 ±â€Š5.74 mm from the IF and 20.05 ±â€Š3.59 degree to the midline. The Mandibular foramen (MBF) was 91.15 ±â€Š1.86 mm horizontally to the margo inferior of incisor. The angle that the MBF-margo inferior of incisor line made with the axial midline was 31.25 ±â€Š2.89 degree. The shortest horizontal distance from the mental foramen (MF) to the facial artery in sagittal plane was 21.90 ±â€Š1.86 mm, while it became 13.00 ±â€Š2.05 mm in coronary section. The horizontal distance from the MF to the margo inferior of incisor in sagittal plane was 22.04 ±â€Š3.22 mm. It turned out to be 25.78 ±â€Š5.23 mm between MF and mid-sagittal line in coronary section. The vertical distance was 25.20 ±â€Š3.06 mm from the upper margin of the second premolar to the MF.The foramens were clearly seen through CTA. Moreover, linear and angular measurements were presented, which makes it safer and wiser for surgeons to consider the biometric data before operations.


Asunto(s)
Puntos Anatómicos de Referencia/diagnóstico por imagen , Angiografía por Tomografía Computarizada/métodos , Mandíbula/anatomía & histología , /diagnóstico por imagen , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Arterias , Huesos/diagnóstico por imagen , Huesos/cirugía , Niño , Cara/irrigación sanguínea , Cara/diagnóstico por imagen , Femenino , Humanos , Incisivo/anatomía & histología , Incisivo/diagnóstico por imagen , Masculino , Mandíbula/diagnóstico por imagen , Mandíbula/patología , Mandíbula/cirugía , Persona de Mediana Edad , Adulto Joven
7.
Dentomaxillofac Radiol ; 49(2): 20190155, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31670576

RESUMEN

OBJECTIVES: To verify quantitative differences of the mandibular cortical and trabecular bone between patients with multiple myeloma (MM) under bisphosphonate (BP) therapy and a control group never exposed to BP. METHODS: Clinical and demographic characteristics were collected through medical records and interviews. Mandibular cortical thickness (MCT) and fractal dimension (FD) were measured on cone beam computed tomography (CBCT) images, on the molar region, in both groups. Additionally, FD was measured on periapical digital intraoral radiography and results were compared to CBCT measurements. RESULTS: There were 33 patients with MM under BP therapy and 28 controls, with no significant differences in gender and age between groups. Pamidronate was used by all MM patients, either associated or not to other types of BP. The median MCT was higher in MM group exposed to BP (5.20 mm) than in controls (3.50 mm, p < 0.001). There were no significant differences in the median FD between patients in the MM group and controls, on CBCT (0.95 vs 0.90, p = 0.814) and periapical digital intraoral radiography (0.98 vs 0.96, p = 0.963), respectively, even when more than one type of BP was used. CONCLUSIONS: The MCT represents an useful tool in the detection of bone dimensional changes caused by BP, in patients with MM. Additional studies are necessary to improve the knowledge on the quantitative evaluation of trabecular jaw bone, in individuals with MM, under BP therapy.


Asunto(s)
Conservadores de la Densidad Ósea , Difosfonatos , Mandíbula , Mieloma Múltiple , Conservadores de la Densidad Ósea/uso terapéutico , Tomografía Computarizada de Haz Cónico , Difosfonatos/uso terapéutico , Humanos , Maxilares/diagnóstico por imagen , Maxilares/efectos de los fármacos , Mandíbula/diagnóstico por imagen , Mandíbula/efectos de los fármacos , Mieloma Múltiple/complicaciones , Radiografía Dental Digital
8.
Dentomaxillofac Radiol ; 49(3): 20190210, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31714158

RESUMEN

OBJECTIVES: The purpose of this study is to evaluate normal ranges of cortical bone Hounsfield units indices through cone beam CT images, and to investigate their relationships with age and sex. METHODS: 700 adult human cone beam CT images were evaluated retrospectively, and divided into 4 age groups. Six different cortical bone Hounsfield unit measurements were applied bilaterally, where gender and age were recorded. Collected data were subjected to statistical analysis and ANOVA tests were used for various comparisons. RESULTS: The cortical bone measurements between female and male patients were significantly different (p<0.05). Cortical bone thickness indices showed greater values in male patients compare to female patients (p<0.05). Quantitative mandibular indices were significantly lower in first age group (18-30 years) than other three older age groups (p<0.01). CONCLUSION: The results of this study seems to propose a persistent alteration in the mandibular cortical bone with age and that this influced by sex. Further studies with larger patient groups are needed to clarify and understand these mandibular indices.


Asunto(s)
Tomografía Computarizada de Haz Cónico , Mandíbula , Adulto , Factores de Edad , Anciano , Hueso Cortical , Femenino , Humanos , Masculino , Mandíbula/diagnóstico por imagen , Mandíbula/crecimiento & desarrollo , Valores de Referencia , Estudios Retrospectivos , Factores Sexuales
9.
Dentomaxillofac Radiol ; 49(3): 20190280, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31718273

RESUMEN

OBJECTIVE: The objective of this study was to determine whether the trabecular volumetric Bone Mineral Density (vBMD) of the middle, body and angle of the mandible correlates with vBMD of the cervical and lumbar vertebrae in a Chinese population. METHODS AND MATERIALS: 661 subjects (270 males, 391 females), ranging from 20 to 59 years of age, were recruited for vBMD measurements by quantitative CT (QCT). Basic information (age, height and weight), vBMD of the mandible (middle, body and angle sites), and vBMD of the cervical and lumbar vertebrae were recorded. Spearman's rank correlation test was used to investigate the association of mandibular with vertebral vBMD. RESULTS: The study cohort comprised 661 subjects: 270 (41%) males, 391 (59%) females. Median age in males was 40 (range, 21-59) years. Median age in females was 41 (range, 20-59) years. Values of the Spearman correlation coefficient between mandibular and vertebral vBMD ranged from R = 0.048 to 0.141. In males, the three correlation coefficients between mandibular and cervical vBMD (middle: R = 0.138; body: R = 0.126; angle: R = 0.122) were all statistically significant (p < 0.05). In females, the correlation between the middle mandibular site and cervical site was statistically significant (R = 0.141, p < 0.01). None of the other correlations examined were statistically significant. CONCLUSION: In this study population, mandibular vBMD was at best weakly correlated with cervical and lumbar vertebral vBMD, indicating that mandibular vBMD should be measured independently for the assessment of mandibular bone status.


Asunto(s)
Densidad Ósea , Mandíbula , Osteoporosis , Enfermedades de la Columna Vertebral , Absorciometría de Fotón , Adulto , Femenino , Humanos , Vértebras Lumbares , Masculino , Mandíbula/diagnóstico por imagen , Persona de Mediana Edad , Osteoporosis/diagnóstico , Enfermedades de la Columna Vertebral/diagnóstico , Tomografía Computarizada por Rayos X , Adulto Joven
10.
J Endod ; 46(1): 40-43, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31843127

RESUMEN

INTRODUCTION: This study evaluated the presence of midmesial canals (MMCs) in a random sample of mandibular molars and the relationship of the intracanal distance between mesiobuccal (MB) and mesiolingual (ML) canal orifices. METHODS: Fifty-one extracted mandibular molars were divided into samples of 3 to 4 teeth, mounted in plaster and boxing wax, and immersed in water before cone-beam computed tomographic (CBCT) imaging. Two endodontic residents completed the access openings. The teeth and the CBCT images were interpreted for the presence of MMCs and the mesial intracanal distance. CBCT software measured the distance between the buccal of the MB canal to the lingual of the ML canal at the pulpal floor to determine the average length between the canals. RESULTS: Seven distinct MMCs were seen both clinically (incidence of 13.725%) and on the CBCT images. Twenty-seven teeth (52.94%) had ambiguous broad isthmi between the MB and the ML orifices. MMCs were present at the furcation level but merged with the MB or ML canal toward the apex in 6 of 7 teeth (85.71%). The mean distance between the mesial canals in teeth with MMCs was 3.643 mm, and it was 3.818 mm for teeth without MMCs. According to independent sample t testing, the P value was >.05. CONCLUSIONS: The incidence of MMCs in mandibular molars appears consistent with the literature. However, there does not appear to be a statistically significant difference in the mesial intracanal distance in teeth with and without MMCs. Visualization of MMCs on CBCTs may be subjective. There does not appear to be a correlation between the presence of MMCs and an increased or decreased mesial intracanal distance.


Asunto(s)
Cavidad Pulpar , Mandíbula , Raíz del Diente , Tomografía Computarizada de Haz Cónico , Cavidad Pulpar/diagnóstico por imagen , Humanos , Incidencia , Mandíbula/diagnóstico por imagen , Diente Molar , Raíz del Diente/diagnóstico por imagen
11.
Acta Cir Bras ; 34(9): e201900906, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31826098

RESUMEN

PURPOSE: To develop 3D anatomical models, and corresponding radiographs, of canine jaw fractures. METHODS: A base model was generated from a mandibular bone scan. With this model it was possible to perform fracture planning according to the anatomical location. RESULTS: The 3D base model of the canine mandible was similar in conformation to the natural bone, demonstrating structures such as canine tooth crowns, premolars and molars, mental foramina, body of the mandible, ramus of the mandible, masseteric fossa, the coronoid process, condylar process, and angular process. It was not possible to obtain detail of the crown of the incisor teeth, mandibular symphysis, and the medullary channel. Production of the 3D CJF model took 10.6 h, used 150.1 g of filament (ABS) and cost US$5.83. CONCLUSION: The 3D canine jaw fractures models, which reproduced natural canine jaw fractures, and their respective radiographic images, are a possible source of educational material for the teaching of veterinary medicine.


Asunto(s)
Educación en Veterinaria/métodos , Imagen Tridimensional/veterinaria , Fracturas Mandibulares/veterinaria , Modelos Anatómicos , Impresión Tridimensional , Animales , Perros , Imagen Tridimensional/métodos , Mandíbula/anatomía & histología , Mandíbula/diagnóstico por imagen , Fracturas Mandibulares/diagnóstico por imagen , Radiografía/veterinaria , Reproducibilidad de los Resultados , Factores de Tiempo
12.
Cient. dent. (Ed. impr.) ; 16(3): 173-179, sept.-dic. 2019. ilus
Artículo en Español | IBECS | ID: ibc-185991

RESUMEN

El objetivo del presente trabajo es la presentación de un caso clínico en el que mostramos dos técnicas quirúrgicas para resolver la atrofia ósea en sentido horizontal. En la implantología actual nos enfrentamos cada vez con más frecuencia a casos con extremas reabsorciones óseas que nos obligan a implementar distintas técnicas quirúrgicas para lograr el éxito de nuestros tratamientos con implantes dentales. La coexistencia de atrofias verticales y horizontales complica la resolución de estos casos con éxito, aunque cada vez con mayor frecuencia nos enfrentamos a este tipo de situaciones más complicadas debido a que los pacientes demandan el tratamiento implantológico incluso en casos muy severos. Por ello, no es infrecuente tener que utilizar técnicas como la expansión de cresta o los implantes cortos de forma combinada en algunas situaciones. En el siguiente caso clínico mostramos una paciente con reabsorción extrema mandibular en ambos sectores posteriores con los dos tipos de reabsorción descritos anteriormente: las zonas posteriores con reabsorción extrema vertical y un abordaje con implantes cortos y una zona anterior con reabsorción extrema horizontal tratada con Split en dos fases mediante implantes expansores transicionales


The objective of this work is the presentation of a clinical case in which we show two surgical techniques to solve the horizontal bone atrophy. In the advanced implant dentistry, different surgical techniques would be required for the successfull treatment of patients presenting severe alveolar ridge atrophy. The presence of vertical and horizontal atrophies increases drastically the difficulty of the clinical case where several surgical techniques will be needed. Therefore, it is not uncommon to performe techniques like the alveolar ridge expansion and short implants in the same mandible or maxilla. The following clinical case presented an advanced horizontal and vertical alveolar atrophy in the right and left posterior regions of the mandible. The treatment plan included the use of short implants to treat the vertical atrophy and the two-stage alveolar ridge split to treat the horizontal atrophy


Asunto(s)
Humanos , Femenino , Persona de Mediana Edad , Atrofia , Odontopatías/diagnóstico por imagen , Implantación Dental/instrumentación , Implantes Dentales , Radiografía Panorámica , Mandíbula/diagnóstico por imagen , Mandíbula/cirugía
13.
J Craniofac Surg ; 30(6): e563-e566, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31756880

RESUMEN

BACKGROUND: The role of virtual surgical planning and three-dimensional printing in improving the accuracy, precision, functional and aesthetic outcomes have been demonstrated in the literature; however, there is a dearth of studies evaluating these parameters. OBJECTIVE: This study was carried out at a tertiary care center in North India to assess the accuracy of virtual surgical planning in mandibular reconstruction. METHOD: All the included patients were preoperatively assessed with a contrast enhanced computed tomography (CECT) of head and neck. Based on the dimensions a patient-specific fibula cutting guide was fabricated by three-dimensional printing. All patients were evaluated with a postoperative CECT at 6 months of follow-up. The precision outcomes were measured by comparing surgical results with the images of the preoperative virtual planning based on several measurements on the reconstructed mandible such as anteroposterior measurement, transverse measurement, height of the mandible, angle of the mandible, and lateral tilt.The secondary outcomes analyzed were the mean total operative time, mean ischemia time, and morbidity parameters. RESULT: Twelve consecutive patients (6 male, 6 female) with mean age of 33.1 ±â€Š11 years who underwent free fibula graft mandibular reconstruction were included in the study. The mean difference in the anteroposterior, transverse, and height dimensions were 0.87 ±â€Š0.43 mm (P = 0.24), 2.43 ±â€Š3.72 mm (P = 0.64), and 1.08 ±â€Š0.67 (P = 0.88), respectively. The difference in the angles of the reconstructed mandible was 2.37 ±â€Š3.92 degrees (P = 0.51) and of lateral tilt was 1.57 ±â€Š1.5 degrees (P = 0.54). The mean total operative time was 639 ±â€Š27.2 minutes and mean ischemia time was 88.4 ±â€Š8.6 minutes. CONCLUSION: All the patients had satisfactory aesthetic results and good oral function at 6 months postoperative period.


Asunto(s)
Peroné/diagnóstico por imagen , Mandíbula/diagnóstico por imagen , Reconstrucción Mandibular , Adulto , Femenino , Colgajos Tisulares Libres , Humanos , Isquemia , Masculino , Mandíbula/cirugía , Persona de Mediana Edad , Tempo Operativo , Periodo Posoperatorio , Impresión Tridimensional , Tomografía Computarizada por Rayos X , Adulto Joven
14.
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
16.
Am J Orthod Dentofacial Orthop ; 156(4): 453-463, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31582117

RESUMEN

INTRODUCTION: Extraction of one mandibular incisor in adolescents and adults can simplify orthodontic treatment in 2 major circumstances: (1) severe crowding of the mandibular but not the maxillary incisors, and (2) mild anterior crossbite with good alignment in both arches. Despite its potential advantages, this method has had limited use in most practices. There have been 3 major objections: (1) the possibility of unsightly black triangles because of loss of interdental papilla height, (2) a possible tooth size discrepancy that would affect occlusal relationships, and (3) patient concerns about a visible extraction site. All 3 objections now can be overcome. METHODS: For 37 consecutively treated single-incisor-extraction patients, preparation of the extraction site for the tooth to be extracted was done by tipping it lingually while simultaneously closing the space in front of it. Treatment outcomes and the effect of age at the time of treatment were evaluated. RESULTS: In patients below age 20, this approach eliminated post-treatment black triangles and almost eliminated partial loss of the interdental papilla. It reduced the previously reported prevalence of these problems in patients aged 20-40 years and did not seem to be helpful in those aged over 40 years. This positive effect was achieved because of maintenance of alveolar crest height that supports the interdental papillae. Tooth size discrepancy caused by incisor extraction was largely compensated by the different labio-lingual orientation of maxillary and mandibular anterior teeth. The extraction space quickly disappeared during extraction site preparation. CONCLUSIONS: The new procedure of extraction site preparation described in this paper offers more favorable outcomes for post-treatment prevalence of black triangles in younger patients but shows limited efficacy in older patients. Camouflage of a mild skeletal Class III problem is the major indication for this extraction pattern. About 3% of Icelandic orthodontic patients appear to be good candidates for this treatment, and this finding should be reasonably generalizable to other populations of European descent.


Asunto(s)
Incisivo/cirugía , Mandíbula/cirugía , Extracción Dental/métodos , Técnicas de Movimiento Dental/métodos , Adolescente , Adulto , Anciano , Cefalometría/métodos , Niño , Estética Dental , Femenino , Humanos , Islandia , Incisivo/diagnóstico por imagen , Masculino , Maloclusión de Angle Clase III/terapia , Mandíbula/diagnóstico por imagen , Persona de Mediana Edad , Fotograbar , Resultado del Tratamiento
17.
Dent Med Probl ; 56(3): 279-283, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31577072

RESUMEN

BACKGROUND: The mandibular incisive canal (MIC) is a neural canal containing one of the lower branches of the inferior alveolar nerve, called the mandibular incisive nerve, which can get damaged and cause complications during the removal of bone from the interforaminal region. OBJECTIVES: The aim of this study was to determine the effect of the inversion filter (IF) on improving the visibility of MIC as compared to the original images. MATERIAL AND METHODS: In this retrospective, descriptive, analytical study, 343 samples of digital panoramic radiography were examined. The images were analyzed with and without IF. The frequency and confidence intervals (CIs) of identifying MIC were used to determine its visibility, both with IF and in the original images. Besides, the difference between the maximum and minimum diameters of the canal as well as the distance from MIC to the alveolar crest and to the mental foramen were examined. For statistical analysis, McNemar's test and the paired t-test were used, and the concordance was calculated using the kappa coefficient. RESULTS: No significant differences were found in the prevalence of the incisive canal, or in its unilateral or bilateral visibility between the original and filtered radiography in this study (p = 0.42 and p = 0.67, respectively). The absolute values of the interval difference between MIC and the mental foramen, the maximum and minimum diameters of MIC, and the distance from MIC to the alveolar crest were statistically significant between the filtered and original radiography, although the difference was clinically unimportant. CONCLUSIONS: The use of IF produced results similar to the original radiography; its application neither increased the clarity nor improved the visibility of the incisive canal.


Asunto(s)
Tomografía Computarizada de Haz Cónico , Mandíbula , Radiografía Dental Digital , Mandíbula/diagnóstico por imagen , Mandíbula/inervación , Radiografía Panorámica , Estudios Retrospectivos
18.
Niger J Clin Pract ; 22(10): 1435-1440, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31607736

RESUMEN

Aims: The aim of this study was to evaluate the mandibular bone changes on panoramic radiographs of thalassemia and sickle cell anemia (SCA) patients using fractal dimension (FD) analysis and to compare the findings obtained from healthy individuals. Materials and Methods: A total of 90 panoramic radiographs (from 30 patients with thalassemia, 30 patients with SCA and 30 healthy individuals) were assessed to measure FD, mandibular cortical width (MCW), panoramic mandibular index (PMI) in the mandible. Three region of interests (ROI) of angulus, corpus, and interdental bone were created. FD was calculated using ImageJ program. Results: In thalassemia group, the mean value of FD was 1.11, 1.03, and 1.02 in interdental bone, corpus, and angulus, respectively. In SCA group, the mean value of FD was 1.10, 1.05, and 1 in interdental bone, corpus, and angulus, respectively. In control group, the mean value of FD was 1.09, 1.04, and 1 in interdental bone, corpus, and angulus, respectively. FD value of interdental bone are significantly higher in thalassemia group than control group. FD values of corpus and angulus values did not show a significant difference between the groups. Conclusions: Fractal analysis may be used and recommended for evaluation of the bone changes induced by hemoglobinopathies.


Asunto(s)
Anemia de Células Falciformes/patología , Mandíbula/diagnóstico por imagen , Radiografía Panorámica/métodos , Talasemia/patología , Adulto , Estudios de Casos y Controles , Femenino , Fractales , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Turquia
19.
Rev. ADM ; 76(5): 272-277, sept.-oct. 2019. ilus, tab
Artículo en Español | LILACS | ID: biblio-1053115

RESUMEN

Introducción: El nervio dentario inferior es una estructura anatómica de la mandíbula, la cual presenta variaciones como el asa mandibular, ambas estructuras están relacionadas con iatrogenias con tratamientos como cirugías orales, regeneraciones óseas e implantes. El objetivo del presente estudio es evaluar las características del asa mandibular y el agujero mentoniano utilizando tomografía axial computarizada de haz cónico (CBCT) en pacientes del Postgrado de Periodoncia de la Universidad Autónoma de Nuevo León. Material y métodos: Se analizaron un total de 110 CBCT, de los cuales 61 entraron al estudio cumpliendo con los criterios de inclusión, se realizaron cortes transversales utilizando el software On Demand® para identifi car y medir el asa mandibular y localizar la posición del agujero mentoniano de ambos lados separando los grupos por género. Resultados: La prevalencia del asa mandibular fue de 32.8% de 61 CBCT que se analizaron, se observó más comúnmente en hombres y de manera bilateral, y cuando fue unilateral sólo se encontró en el lado derecho, la longitud promedio fue de 6 ± 1 mm. El agujero mentoniano se detectó en mayor porcentaje apical al segundo premolar inferior con un diámetro promedio de 3.5 ± 0.5 mm, alejándose de la raíz del diente adyacente en un promedio de 6 ± 1 mm y del borde de la mandíbula 12.5 mm ± 0.5 mm. Conclusión: Es de suma importancia identifi car las características anatómicas del asa mandibular y localizar la posición del agujero mentoniano durante la planifi cación del tratamiento para evitar complicaciones durante y después del acto quirúrgico (AU)


Introduction: The inferior dental nerve is an anatomical structure of the mandible which presents variations such as the anterior loop, both structures are related to iatrogenies with treatments such as oral surgeries, bone regenerations and implants. The aim of the present study is to evaluate the characteristics of the anterior loop and the mental foramen using cone beam computed tomography (CBCT) in patients of the Graduate Periodontics Program, School of Dentistry, Universidad Autónoma de Nuevo León. Material and methods: 110 CBCT were analyzed of which 61 entered the study fulfi lling the inclusion criteria, cross sections were made using the On Demand® software to identify and measure the anterior loop and locate the position of the mental foramen both sides separating our groups by gender. Results: The prevalence of the anterior loop was 32.8% of 61 CBCT that were analyzed, it was found more commonly in men and bilaterally, and when it was unilateral only found on the right side, the average length was 6 ± 1 mm. The mental hole was found in greater percentage apical to the second lower premolar with an average diameter of 3.5 ± 0.5 mm, moving away from the root of the adjacent tooth by an average of 6 ± 1 mm and from the edge of the mandible 12.5 ± 0.5 mm. Conclusion: It is very important to locate these anatomical structures during treatment planning and avoid complications during and after the surgical act (AU)


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Anciano , Tomografía Computarizada de Haz Cónico , Mandíbula/anatomía & histología , Mandíbula/diagnóstico por imagen , Factores Sexuales , Epidemiología Descriptiva , Análisis Estadístico , Estudios Retrospectivos , Nervio Mandibular/anatomía & histología , México
20.
Comput Methods Biomech Biomed Engin ; 22(16): 1303-1310, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31482715

RESUMEN

Accurate CT bone segmentation is essential to develop chair-side manufacturing of implants based on additive manufacturing. We herewith present an automated method able to accurately segment challenging bone regions, while simultaneously providing anatomical correspondences. The method was evaluated on demanding regions: normal and osteoarthritic scapulae, healthy and atrophied mandibles, and orbital bones. On average, results were accurate with surface distances of approximately 0.5 mm and average Dice coefficients >90%. Since anatomical correspondences are propagated during the segmentation process, this approach can directly yield anatomical measurements, provide design parameters for personalized surgical instruments, or determine the bone geometry to manufacture patient-specific implants.


Asunto(s)
Huesos/diagnóstico por imagen , Procesamiento de Imagen Asistida por Computador , Modelos Teóricos , Estadística como Asunto , Tomografía Computarizada por Rayos X , Algoritmos , Automatización , Humanos , Mandíbula/diagnóstico por imagen
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA