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1.
Biomed Res Int ; 2022: 4695193, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35229002

RESUMO

OBJECTIVE: To analyze the width and height ratios of maxillary anterior teeth at different crown levels through photographs, 3D, and plaster dental model techniques in a subset of the Pakistani population. Material and Methods. This clinical study consisted of 230 participants. The maxillary impression, standardized photographs, and models were constructed for crown width and height analysis. The SPSS version 25 was used for statistical analysis. Descriptive statistics were carried out for mean, standard deviation, and percentage calculation of teeth width and height, gender, and age of participants. Paired t-test analysis was carried out to compare the dependent variables (teeth size, width, and height ratios) with independent variables (techniques applied, side disparity). A p value of ≤ 0.05 was considered statistically significant. RESULTS: The mean width and height of maxillary anterior teeth obtained through photographs, 3D, and plater models were statistically different. The 3D dental model analysis showed reliable and accurate results. The mean width and height ratio of teeth were different on both sides of the arch. There was a significant difference (p = 0.001) in crown width-height ratios at different crown levels. CONCLUSION: The width and height ratios in the studied population were different at various crown levels. The dimensions of teeth varied from the incisal to the cervical part of the crown. Hence, rather than relying on a single, fixed ratio of 78% to 80% suggested by researchers for anterior teeth, the clinician should adopt different crown width-height ratios to restore teeth with the optimum esthetic outcome.


Assuntos
Dente Canino/anatomia & histologia , Estética Dentária , Face/anatomia & histologia , Incisivo/anatomia & histologia , Coroa do Dente/anatomia & histologia , Adulto , Estatura , Estética , Feminino , Humanos , Masculino , Odontometria , Fotografia Dentária , Fatores Sexuais
2.
Sci Rep ; 12(1): 3819, 2022 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-35264608

RESUMO

Rodents are characterised by a distinctive masticatory apparatus which includes a single pair of enlarged and continually growing incisors. This morphology, termed diprotodonty, has also independently evolved in a number of other mammals, including the aye-aye. This study examined the functional significance of the internal "root" of the elongated rodent-like incisor. The mandibles of four rodents and an aye-aye were modelled to exhibit incrementally shorter incisor roots. Finite element analysis was used to predict stress and strain patterns across the jaw to determine whether the length of the incisor root contributes to the resistance of mechanical forces encountered in the mandible during incision. It was found that von Mises stresses increase in the region of the mandible local to where the incisor is removed, but that the stress distribution across the wider mandible is only minimally affected. Thus, the long internal incisor appears to play a small role in resisting bending forces close to the incisor alveolus, and may act with the arch-like mandibular shape to strengthen the mandible in this region. However, the impact across the whole mandible is relatively limited, suggesting the highly elongate incisor in diprotodont mammals may be principally driven by other factors such as rapid incisor wear.


Assuntos
Incisivo , Roedores , Animais , Análise de Elementos Finitos , Incisivo/anatomia & histologia , Mandíbula/anatomia & histologia , Mandíbula/cirurgia , Roedores/anatomia & histologia , Raiz Dentária
3.
ScientificWorldJournal ; 2022: 7226998, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35185395

RESUMO

BACKGROUND: Initial bone thickness has a substantial impact on the success of dental implant treatments. The objective of the current study was to analyze the thickness of the buccal and alveolar bone at the central incisors using CBCT in relation to gender and side to determine the anatomical features and choose the best implant treatment option for minimizing the surgical complications. METHODS: One hundred CBCT images were investigated (50 females and 50 males, aged 20 to 50 years old). The buccal bone thickness and alveolar bone thickness were evaluated for right and left sides of each subject at three sites; C: crest (3 mm); M: middle (6 mm); A: apical (9 mm) from the cementoenamel junction. RESULTS: The mean thickness of buccal bone was less than 2 mm on the incisors according to side and gender. Buccal bone thickness revealed a statistically significant difference between right and left sides at the apical point in both females and males with p values of (p ≤ 0.001) and (0.001), respectively. The buccal bone thickness displayed statistically significant differences between genders at all sites. The alveolar thickness demonstrated similar significant differences between genders except for the crest site. CONCLUSIONS: Iraqi participants had about 1 mm buccal bone thickness at 3 mm apical from the CEJ in right and left central incisors with a progressive rise in bone thickness to be less than 2 mm at the apex. Alveolar bone also showed the same increase in bone thickness from crest to apex. Bone thickness was greater in males than females. The present study provided valuable CBCT data on bone thickness of the esthetic maxillary region as a preoperative analysis for establishing an immediate implant treatment plan with aesthetically pleasing long-term outcomes.


Assuntos
Processo Alveolar/diagnóstico por imagem , Incisivo/diagnóstico por imagem , Maxila/diagnóstico por imagem , Adulto , Processo Alveolar/anatomia & histologia , Tomografia Computadorizada de Feixe Cônico , Feminino , Humanos , Incisivo/anatomia & histologia , Iraque , Masculino , Maxila/anatomia & histologia , Pessoa de Meia-Idade , Adulto Jovem
4.
J Esthet Restor Dent ; 34(4): 583-591, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35182447

RESUMO

OBJECTIVE: This case report describes the orthodontic and prosthetic rehabilitation of a patient with resorption of the roots of the maxillary central incisors due to the ectopic maxillary canines. CLINICAL CONSIDERATIONS: A 16-year-old woman presented with severe resorption of the roots of the maxillary central incisors due to the ectopic maxillary canines. The impacted canines were orthodontically tracted with a lingual arch-supporting temporary central incisors and vertical elastics, and, undesirable root proximity was later corrected by moving the canines distally 1.5 mm apart. Gingival replacement cords were placed into the gingival sulcus of the canines, and tooth preparation was performed along with rotary gingival curettage of the interdental papilla. Convex form was provided for the mesial and labio-distal subgingival contour of the restorations. CONCLUSIONS: The creeping attachment of the interdental papilla was successfully achieved by the orthodontic arrangement of interdental distance and the prosthetic stimulus via the retraction cord, rotary curettage, and convex mesial subgingival contours. In addition, selective retraction of the labio-distal gingiva by overcontoured restorations moved the gingival zenith position (GZP) distally. Finally, the canine crown morphology and gingival level mimicked the central incisors. CLINICAL SIGNIFICANCE: This clinical report introduces a treatment workflow of to recover the esthetic disturbance due to severe root resorption of the maxillary central incisors associated with impacted maxillary canines. The present orthodontic and prosthetic procedure can improve both hard and soft tissue esthetics and could be used in similar cases, such as malformed teeth and tooth autotransplantation or transposition with disturbances in the interdental papilla height or the GZP.


Assuntos
Reabsorção da Raiz , Dente Impactado , Adolescente , Dente Canino , Humanos , Incisivo/anatomia & histologia , Maxila , Reabsorção da Raiz/terapia , Dente Impactado/complicações , Dente Impactado/terapia
5.
Molecules ; 26(20)2021 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-34684695

RESUMO

The aim of this study was to evaluate the effect of biologically oriented preparation technique on the stress concentration of endodontically treated upper central incisors restored with zirconia crown (yttria-stabilized zirconia polycrystalline ceramic) through finite element analysis (FEA). Four models of maxillary central incisors containing enamel, dentin, periodontal ligament, cortical and medullary bone were created in CAD. Each model received a polymeric core-build up with nanofilled dental resin composite. The evaluated models were SM-preparation in shoulder 90°; CM-chamfer preparation; BOPT-biologically oriented preparation technique and BOPTB-BOPT preparation 1 mm below the cement-enamel junction. All models received zirconia crowns (5Y-TZP), fiberglass post and 1 mm ferrule. The models were imported into the analysis software with parameters for mechanical structural testing using the maximum principal stress and the tensile strength as the analysis criteria. Then, load of 150 N was applied at the cingulum with 45° slope to the long axis of the tooth, with the fixed base for each model. The type of marginal preparation affected the stresses concentration in endodontically treated teeth and in the zirconia crown margin. Considering the stress magnitude only, BOPT is a viable option for anterior monolithic zirconia crowns; however, with the highest stress magnitude at the restoration margin.


Assuntos
Cerâmica/química , Resinas Compostas/química , Coroas , Análise de Elementos Finitos/normas , Incisivo/cirurgia , Dente não Vital/cirurgia , Zircônio/química , Vidro/química , Humanos , Incisivo/anatomia & histologia , Incisivo/efeitos dos fármacos , Estresse Mecânico , Resistência à Tração
6.
J Oral Biosci ; 63(4): 337-350, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34547454

RESUMO

OBJECTIVES: This systematic review was designed to measure the pooled prevalence of morphological variations in the root canal of permanent incisors and canines among Asian adults. METHODS: An electronic search was conducted in the PubMed, Scopus, and EBSCO databases, and relevant studies were included. Studies reporting on the Vertucci canal configuration (types I to VIII) were included. A weighted proportion (pooled prevalence) with 95% confidence interval was calculated for each canal type, and the outcome was stratified based on country, technique of assessment, gender, and age. RESULTS: Sixty articles were included in the final review. In all types of maxillary anterior teeth, the pooled prevalence of type I canal configuration was greater than 97%, whereas mandibular central incisor, lateral incisor, and canines had a prevalence of 78.4%, 69.2%, and 91.1%, respectively. Studies considering mandibular anterior teeth as a single entity had a lower prevalence of type I configuration (70.1%). Variations in root canal configurations were also observed between countries. Among gender, males had a significantly lower prevalence of type I and a higher prevalence of type II and III canal configurations in the mandibular anterior teeth. A variation in canal types was also noted with advancing age, with younger age groups showing more variations. CONCLUSION: The majority of maxillary and mandibular anterior teeth have type I Vertucci canal configuration, but variations in mandibular anterior teeth, especially lateral incisors, are also common. Variations were also observed among population, gender, age, and prevalence based on the diagnostic techniques used.


Assuntos
Cavidade Pulpar , Incisivo , Animais , Tomografia Computadorizada de Feixe Cônico/métodos , Cavidade Pulpar/anatomia & histologia , Incisivo/anatomia & histologia , Masculino , Mandíbula , Raiz Dentária/anatomia & histologia
7.
Surg Radiol Anat ; 43(6): 1009-1018, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34023911

RESUMO

PURPOSE: The aim of this study was to analyze the morphologic features of alveolus in relatively healthy maxillary and mandibular incisors using cone-beam-computed tomography (CBCT). METHODS: CBCT images of 318 patients were retrospectively acquired. Alveolar bone in incisive area was divided into: type 1 (thick), type 2 (relatively thick with mono-plate concavity), type 3 (thin with double-plate concavities), and type 4 (vulnerably thin). Alveolus prevalence and widths were analyzed statistically relative to age, gender, and molar relationship. RESULTS: Prevalence of type 1 alveolus was 78.9% in maxillary central incisors, 15.1% in maxillary lateral incisors, 24.1% in mandibular central incisors, and 5.0% in mandibular lateral incisors. Type 2 alveolus was commonly observed in the maxillary lateral incisors (82.2%), mandibular central incisors (66.2%), and mandibular lateral incisors (87.9%). Prevalence of type 3 and 4 alveoli ranged from 0.0 to 9.4%. As for maxillary central incisors, type 1 was the widest both at the alveolar crest (7.77 ± 0.58 mm) and apical area (9.05 ± 1.86 mm), while type 3 had the lowest width at the apical region (4.08 ± 0.51 mm). Among maxillary central incisors, prevalence of type 1 tended to decrease with age. At all maxillary and mandibular incisor sites, alveolus widths were significantly thicker in males than in females. At maxillary lateral incisor and mandibular incisor sites, prevalence of alveolus type was significantly different among three molar relationships. CONCLUSION: A 4-type classification system was suggested for alveolus morphology in incisive region. Identification of alveolus type might aid in the corresponding treatment.


Assuntos
Processo Alveolar/anatomia & histologia , Incisivo/anatomia & histologia , Mandíbula/anatomia & histologia , Maxila/anatomia & histologia , Adolescente , Adulto , Fatores Etários , Processo Alveolar/diagnóstico por imagem , Tomografia Computadorizada de Feixe Cônico , Feminino , Humanos , Incisivo/diagnóstico por imagem , Masculino , Mandíbula/diagnóstico por imagem , Maxila/diagnóstico por imagem , Pessoa de Meia-Idade , Radiografia Dentária , Estudos Retrospectivos , Fatores Sexuais , Adulto Jovem
8.
Dental Press J Orthod ; 26(1): e211928, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33759965

RESUMO

OBJECTIVE: To study the influence of black space between the maxillary central incisors on the aesthetic visual perception of the face, via eye-tracking and visual analogue scale (VAS). METHODS: Black space between the central incisors was created, for both sexes, as follows: control, 1-mm black space, 2-mm black space and 3-mm black space. Ninety raters participated in this study, divided into three groups: 30 laypeople, 30 nonorthodontists, and 30 orthodontists. After the visual calibration of each observer, eight photographs were presented in the Ogama® software concomitant with the use of the hardware The Eye Tribe®. Ogama generated information depending on the eye-tracking of each rater, regarding the time until the first fixation, time of fixation, heatmap, scanpath, and total time of fixation, to evaluate the areas deemed to be of interest according to the raters. Later on, the VAS was used, where each rater evaluated the images in an album on a scale of zero to 10 points. RESULTS: The eyes and mouth were the areas more often noticed by the raters according to the heatmaps, while no significant difference was observed in time until the first fixation between the three groups of raters (p> 0.05). However, regarding the time of fixation on the mouth, a significant difference was observed (p< 0.05) when comparing the three groups. CONCLUSION: Black space has a negative effect on the aesthetic perception of the face. The amount of attention on the mouth is correspondent to the size of the black space.


Assuntos
Estética Dentária , Incisivo , Tecnologia de Rastreamento Ocular , Feminino , Humanos , Incisivo/anatomia & histologia , Incisivo/diagnóstico por imagem , Masculino , Sorriso , Escala Visual Analógica
9.
Sci Rep ; 11(1): 1132, 2021 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-33441959

RESUMO

Mutations of Odontogenesis-Associated Phosphoprotein (ODAPH, OMIM *614829) cause autosomal recessive amelogenesis imperfecta, however, the function of ODAPH during amelogenesis is unknown. Here we characterized normal Odaph expression by in situ hybridization, generated Odaph truncation mice using CRISPR/Cas9 to replace the TGC codon encoding Cys41 into a TGA translation termination codon, and characterized and compared molar and incisor tooth formation in Odaph+/+, Odaph+/C41*, and OdaphC41*/C41* mice. We also searched genomes to determine when Odaph first appeared phylogenetically. We determined that tooth development in Odaph+/+ and Odaph+/C41* mice was indistinguishable in all respects, so the condition in mice is inherited in a recessive pattern, as it is in humans. Odaph is specifically expressed by ameloblasts starting with the onset of post-secretory transition and continues until mid-maturation. Based upon histological and ultrastructural analyses, we determined that the secretory stage of amelogenesis is not affected in OdaphC41*/C41* mice. The enamel layer achieves a normal shape and contour, normal thickness, and normal rod decussation. The fundamental problem in OdaphC41*/C41* mice starts during post-secretory transition, which fails to generate maturation stage ameloblasts. At the onset of what should be enamel maturation, a cyst forms that separates flattened ameloblasts from the enamel surface. The maturation stage fails completely.


Assuntos
Ameloblastos/fisiologia , Amelogênese , Proteínas da Matriz Extracelular/metabolismo , Fosfoproteínas/metabolismo , Amelogênese Imperfeita/genética , Amelogênese Imperfeita/patologia , Animais , Esmalte Dentário/crescimento & desenvolvimento , Esmalte Dentário/ultraestrutura , Proteínas da Matriz Extracelular/química , Proteínas da Matriz Extracelular/genética , Técnicas de Introdução de Genes , Hibridização In Situ , Incisivo/anatomia & histologia , Camundongos , Dente Molar/anatomia & histologia , Odontogênese , Fosfoproteínas/química , Fosfoproteínas/genética
10.
Am J Phys Anthropol ; 175(1): 172-186, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33368148

RESUMO

OBJECTIVES: Human tooth enamel retains evidence of growth in the form of Retzius lines. The number of daily growth increments between the regularly occurring lines defines their repeat interval, or periodicity. Retzius periodicity is often incorporated into enamel formation times, age-at-death reconstructions, or used to provide a basis from which to explore an underlying biorhythm. Biological anthropologists typically assume that RP remains constant within an individual and does not vary along the tooth-row. Here, we test that assumption. MATERIALS AND METHODS: RP was calculated from n = 223 thin sections of human permanent teeth from individuals of British and southern African origin. Forty individuals provided multiple teeth (n = 102 teeth) and a further 121 individuals each provided a single tooth. RESULTS: We report first evidence that RP of permanent teeth does not always remain constant within an individual. Of those individuals that provided multiple teeth, 42% (n = 17/40) demonstrated a decrease in RP along the tooth row, with most shifting by two or more days (n = 11). Across the entire sample, mean RP of anterior teeth was significantly higher than molars. Mean premolar RP tended to be intermediate between anterior teeth and molars. DISCUSSION: Our data do not support the assumption that RP invariably remains constant within the permanent teeth of an individual. Transferring RP from molars to incisors within an individual can result in a miscalculation of formation time and age-at-death by up to 1 year. Implications for biological anthropologists and the source of the underlying long period biorhythm are discussed.


Assuntos
Esmalte Dentário , Incisivo , Dente Molar , Periodicidade , Antropologia Física , Esmalte Dentário/anatomia & histologia , Esmalte Dentário/crescimento & desenvolvimento , Dentição Permanente , Feminino , Humanos , Incisivo/anatomia & histologia , Incisivo/crescimento & desenvolvimento , Masculino , Modelos Estatísticos , Dente Molar/anatomia & histologia , Dente Molar/crescimento & desenvolvimento
11.
Dental press j. orthod. (Impr.) ; 26(1): e211928, 2021. tab, graf
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1154061

RESUMO

ABSTRACT Objective: To study the influence of black space between the maxillary central incisors on the aesthetic visual perception of the face, via eye-tracking and visual analogue scale (VAS). Methods: Black space between the central incisors was created, for both sexes, as follows: control, 1-mm black space, 2-mm black space and 3-mm black space. Ninety raters participated in this study, divided into three groups: 30 laypeople, 30 nonorthodontists, and 30 orthodontists. After the visual calibration of each observer, eight photographs were presented in the Ogama® software concomitant with the use of the hardware The Eye Tribe®. Ogama generated information depending on the eye-tracking of each rater, regarding the time until the first fixation, time of fixation, heatmap, scanpath, and total time of fixation, to evaluate the areas deemed to be of interest according to the raters. Later on, the VAS was used, where each rater evaluated the images in an album on a scale of zero to 10 points. Results: The eyes and mouth were the areas more often noticed by the raters according to the heatmaps, while no significant difference was observed in time until the first fixation between the three groups of raters (p> 0.05). However, regarding the time of fixation on the mouth, a significant difference was observed (p< 0.05) when comparing the three groups. Conclusion: Black space has a negative effect on the aesthetic perception of the face. The amount of attention on the mouth is correspondent to the size of the black space.


RESUMO Objetivo: Avaliar a percepção visual e estética do espaço negro entre os incisivos centrais superiores, via rastreamento do olhar e escala visual analógica (EVA). Métodos: Manipulou-se o espaço negro entre os incisivos centrais superiores, para ambos os sexos, da seguinte forma: imagem controle, espaço negro de 1 mm, espaço negro de 2 mm e espaço negro de 3 mm. Participaram desse estudo noventa avaliadores, divididos em três grupos: 30 leigos, 30 cirurgiões-dentistas e 30 ortodontistas. Após a calibração visual de cada observador, foram projetadas oito fotografias no software OGAMA® em conjunto com o hardware The Eye Tribe®. O OGAMA gerou informações do rastreamento do olhar de cada avaliador com relação ao tempo até a primeira fixação, mapa de calor, trajetória do olhar e tempo total de fixação para avaliar as áreas consideradas de interesse, de acordo com os avaliadores. Posteriormente, utilizou-se a EVA para avaliar as imagens a partir de um álbum, em uma escala de 0 a 10 pontos. Resultados: Os olhos e a boca foram as áreas com maior fixação pelos avaliadores, de acordo com os mapas de calor. Os resultados estatísticos não apresentaram diferença estatisticamente significativa entre os três grupos de avaliadores (p> 0,05), quanto ao tempo até a primeira fixação. Porém, em relação ao tempo de fixação na boca, observou-se diferença estatisticamente significativa (p< 0,05) na comparação dos três grupos. Conclusão: O espaço negro apresentou um efeito negativo na percepção estética da face. O aumento de fixação na boca correspondeu ao aumento do tamanho do espaço negro.


Assuntos
Humanos , Masculino , Feminino , Afro-Americanos , Estética Dentária , Tecnologia de Rastreamento Ocular , Incisivo , Sorriso , Escala Visual Analógica , Incisivo/anatomia & histologia , Incisivo/diagnóstico por imagem
12.
P R Health Sci J ; 39(4): 288-293, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33320456

RESUMO

OBJECTIVE: Compare maxillary anterior dentition measurements, using Chu's proportion gauge with a T-bar tip (PG-TT) and a Two-Tip Compass (T-TC), in a group of Puerto Ricans, to determine the reliability of the PG-TT. METHODS: This cross-sectional study was conducted at the University of Puerto Rico, School of Dental Medicine, Medical Sciences Campus. The participants (18-35 years old) were dental students or employees of the university. Previously, the examiner had been trained and calibrated in instrument usage. Calibration participants (n = 16) received an oral exam, prophylaxis, and a chlorhexidine mouthwash for home use. After 3 days, the upper-anterior teeth were measured using the 2 instruments. The agreement was determined using weighted kappa statistics (Kw), and 0.80 was the minimum acceptable level. The examiner achieved almost perfect agreement (inter-examiner KwT-TC = 0.95 [0.96-0.93]; KwPG-TT = 0.82 [0.81-0.87]) with a reference examiner. RESULTS: Fifty participants (25 women and 25 men) were evaluated. Length: The teeth of the men presented an unacceptable level of agreement, except for in the right central incisors. For the women, a strong level of agreement was observed only in the lateral incisors and left canines. When the teeth of both sexes were considered, a strong level of agreement was detected, except for in the right canines and left central incisors. Width: The level of agreement was unacceptable, except for in the right canines (distal). CONCLUSION: T-TC is a more reliable instrument to measure tooth dimensions as compared to the PG-TT.


Assuntos
Dente Canino/anatomia & histologia , Incisivo/anatomia & histologia , Adolescente , Adulto , Estudos Transversais , Dentição , Feminino , Humanos , Masculino , Maxila , Odontometria/métodos , Porto Rico , Reprodutibilidade dos Testes , Fatores Sexuais , Adulto Jovem
13.
Medicine (Baltimore) ; 99(43): e22778, 2020 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-33120788

RESUMO

BACKGROUND: To analyze the sagittal positions of the mandibular prominence and maxillary central incisors in adult Chinese Han men to establish their aesthetic profile characteristics. METHODS: Seventy-four Chinese Han men aged 18 to 40 years underwent cone beam computed tomography for detecting the distances between Glabella and Subnasale, Subnasale and Menthon of soft tissue, Condyle and Gonion, Pogonion and Pogonion's Anterior Limit Line, Facial Axis point of maxillary central incisor and the Goal Anterior Limit Line as well as the angle of the Occlusal Plane. Dolphin Imaging and Photoshop software packages were used to generate silhouette profiles. Thirteen orthodontists assessed the silhouette profiles and assigned visual analog scale scores. Scores >70 were assigned to the aesthetic (group 1), scores of 60to 70 to the general (group 2), scores of 50 to 60 to the acceptable (group 3), and scores of <50 to the unaesthetic profile (group 4). RESULTS: A total of 15 men were assigned to group 1, 35 to group 2, 14 to group 3, and 10 to group 4. There were no significant differences in the variables examined between groups 1, 2, and 3, but comparing group 1 with group 4, Pogonion and Pogonion's Anterior Limit Line (1.16 ±â€Š2.61 mm vs -1.44 ±â€Š2.92 mm, P = .046) and Facial Axis-Goal Anterior Limit Line (-0.61 ±â€Š2.54 mm vs 1.70 ±â€Š2.62 mm, P = .038) there were significant differences. CONCLUSION: Compared with the unaesthetic profile group, the sagittal positions of the maxillary central incisors were slightly posterior, and the chin was slightly anterior in adult Chinese Han men with an aesthetic profile.


Assuntos
Incisivo/anatomia & histologia , Incisivo/diagnóstico por imagem , Maxila/anatomia & histologia , Maxila/diagnóstico por imagem , Adolescente , Adulto , Cefalometria/métodos , Queixo/anatomia & histologia , Queixo/diagnóstico por imagem , China , Tomografia Computadorizada de Feixe Cônico/métodos , Humanos , Masculino , Mandíbula/anatomia & histologia , Mandíbula/diagnóstico por imagem , Estudos Prospectivos , Valores de Referência , Adulto Jovem
14.
Int. j. morphol ; 38(5): 1386-1391, oct. 2020. tab
Artigo em Inglês | LILACS | ID: biblio-1134453

RESUMO

SUMMARY: The incisors are a key factor in dental occlusion and dentofacial aesthetics; therefore, the sagittal position and inclination of the incisors is a key parameter in diagnosis and orthodontic treatment planning. In some cases, the orthodontist will use more than one cephalometric analysis, and thus different results can be obtained. The aim of this study was to establish the diagnostic agreement among the different cephalometric measurements used to determine the anteroposterior position and the inclination of the incisors. Lateral cephalometric radiograms of patients between 18 and 59 years old were measured (n=260). Digital cephalometric measurements were made with Dolphin Imaging software, by a single calibrated operator. Here, a specific cephalometric analysis was designed in the software analysis editor. The results for each variable and each measurement were registered and compared. Fleiss's Kappa statistical tests, Cohen's Kappa, and Kendall's coefficient were used to determine the strength of agreement using the Minitab software. The results showed diagnostic strength agreement between slight and moderate among measurements of the same variable. This indicates that same diagnosis might not be obtained when using different approaches to measure the anteroposterior position and inclination of the incisors. It was concluded that there is a difference in the diagnosis between one measurement and another because the results showed slight or moderate strength of agreement. However, in some cases, better agreement was found when the measurements were compared as a function of the diagnostic response.


RESUMEN: Los incisivos son un factor clave en la oclusión dental y la estética dentofacial; por lo tanto, la posición sagital y la inclinación de los incisivos es un parámetro clave en el diagnóstico y la planificación del tratamiento de ortodoncia. En algunos casos, el ortodoncista utilizará más de un análisis cefalométrico y, por lo tanto, se pueden obtener resultados diferentes. El objetivo de este estudio fue establecer el acuerdo de diagnóstico entre las diferentes mediciones cefalométricas utilizadas para determinar la posición anteroposterior y la inclinación de los incisivos. Se midieron radiografías cefalométricas laterales de pacientes entre 18 y 59 años (n = 260). Las mediciones cefalométricas digitales se realizaron con el software Dolphin Imaging, por un solo operador calibrado. Aquí, se diseñó un análisis cefalométrico específico en el editor de análisis de software. Los resultados para cada variable y cada medición se registraron y compararon. Las pruebas estadísticas Kappa de Fleiss, Kappa de Cohen y el coeficiente de Kendall se usaron para determinar la fuerza del acuerdo utilizando el software Minitab. Los resultados mostraron un acuerdo de fuerza diagnóstica entre leve y moderado entre las mediciones de la misma variable. Esto indica que no se puede obtener el mismo diagnóstico cuando se utilizan diferentes enfoques para medir la posición anteroposterior y la inclinación de los incisivos. Se concluyó que existe una diferencia en el diagnóstico entre una medición y otra porque los resultados mostraron una fuerza de acuerdo leve o moderada. Sin embargo, en algunos casos, se encontró un mejor acuerdo cuando se compararon las mediciones en función de la respuesta de diagnóstico.


Assuntos
Humanos , Adolescente , Adulto , Adulto Jovem , Cefalometria/métodos , Incisivo/anatomia & histologia , Ortodontia , Estudos Transversais , Estudos Retrospectivos , Diagnóstico , Estética , Incisivo/diagnóstico por imagem
15.
Acta Odontol Latinoam ; 33(1): 22-26, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32621595

RESUMO

Cone Beam Computed Tomography (CBCT) has modified the perspective of dentistry images, providing manipulable threedimensional images with a 1:1 patient:image ratio. Treatments and diagnosis are modified or corroborated by CBCT; however, its accuracy in thin structures such as cortical bone has been subjected to critical review. The aim of this study is to correlate the measurement of vestibular alveolar bone height using direct measurements and measurements performed with cone-beam tomographic images with standard (SD) voxel resolution. Thirty incisor and premolar teeth of patients undergoing open curettage were measured with a high-precision caliper and with Cone Beam Computed Tomography (CBCT) at an SD resolution of 0.16 mm voxels in a 3D Orthophos XG Sirona scanner. Intra-observer evaluation was performed using the intraclass correlation coefficient (ICC). Direct measurements and CBCT measurements were correlated using Pearson correlation (PCC). The mean difference between indirect and direct measurements was 3.15 mm. Paired t test and Pearson Correlation coefficient determined that all measurements differed statistically from each other with p<0.05. With the CT scanner and protocol used in this study, CBCT images do not enable accurate evaluation of vestibular alveolar bone height.


La tomografía de haz cónico (CBCT) ha modificado la perspectiva de la imagenología en odontología que brinda una imagen tridimensional manipulable con una relación 1:1, paciente: imagen. Los tratamientos y diagnósticos se ven modificados o corroborados por el CBCT; sin embargo, la exactitud que presenta en estructuras delgadas como las corticales óseas ha sido sometida a críticas. El objetivo fue correlacionar la medición de la altura del hueso alveolar vestibular mediante mediciones directas y las realizadas con imágenes tomográficas de haz cónico con resolución de vóxel estándar (SD). Treinta dientes incisivos y premolares de pacientes sometidos a un curetaje abierto se midieron con un calibrador de alta precisión y una tomografía computarizada de haz cónico (CBCT) a una resolución SD de 0,16 mm de vóxeles en un escáner 3D Orthophos XG Sirona. La evaluación intraobservador se realizó utilizando el coeficiente de correlación intraclase (ICC), y las mediciones directas y las mediciones CBCT se correlacionaron utilizando la correlación de Pearson (PCC). La diferencia media entre las mediciones indirectas y directas fue de 3,15 mm. La prueba t pareada y el Coeficiente de Correlación de Pearson determinaron que todas las mediciones fueron estadísticamente diferentes entre sí con una p <0.05. Con el escáner de TC y el protocolo utilizado en este estudio, las imágenes CBCT no permiten una evaluación precisa de la altura del hueso alveolar vestibular.


Assuntos
Processo Alveolar/diagnóstico por imagem , Dente Pré-Molar/diagnóstico por imagem , Tomografia Computadorizada de Feixe Cônico/normas , Incisivo/diagnóstico por imagem , Processo Alveolar/anatomia & histologia , Dente Pré-Molar/anatomia & histologia , Tomografia Computadorizada de Feixe Cônico/métodos , Precisão da Medição Dimensional , Humanos , Incisivo/anatomia & histologia , Reprodutibilidade dos Testes
16.
Acta Odontol Latinoam ; 33(1): 33-37, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32621597

RESUMO

This study evaluated the internal morphology of lower incisors using computerized microtomography (micro-CT) images. Eighty-nine lower incisors were scanned by micro-CT and reconstructed with NRecon software. 2D parameters (perimeter, root length, circularity and canal diameter) and 3D parameters (volume, surface area and structure model index) were evaluated with CTAn and CTVol software. The results are presented descriptively. It was found that 89.9% of the canals had a single main root canal (type I), followed by type II (6.7%) and III (3.4%), while 5.6% of the specimens presented lateral canals and 1.1% had an apical delta. Mean volume and surface area were 31.80mm³ and 90.58mm², respectively. The most prevalent shape of the root canal at CEJ level was circular (41.6%) and 1mm from the apex, 73% of the samples were classified as oval. Lower incisors with internal anatomical variations may offer a high degree of technical complexity and may result in treatment failure.


Este estudo avaliou a morfologia interna dos dentes incisivos inferiores utilizando imagens de microtomografia computadorizada (micro-TC). 89 incisivos inferiores foram escaneados or micro-CT e reconstruídos com o programa NRecon. Parâmetros 2D - perímetro, comprimento da raiz, circularidade e diâmetro do canal - e parâmetros 3D - volume, área superficial e índice de modelo de estrutura - foram avaliados com os softwares CTAn e CTVol. Os resultados foram apresentados de forma descritiva. 89,9% dos canais apresentaram um único canal radicular principal (tipo I), seguido pelo tipo II (6,7%) e III (3,4%). 5,6% dos espécimes apresentavam canais laterais e 1,1% delta apical. O volume médio e a área de superfície foram 31,80mm³ e 90,58mm², respectivamente. A forma mais prevalente do canal radicular no nível da CEJ foi circular (41,6%) e a 1 mm do ápice, 73% das amostras foram classificadas como ovais. Incisivos inferiores com variações anatômicas internas podem oferecer um alto grau de complexidade técnica e resultar em falha do tratamento.


Assuntos
Cavidade Pulpar/diagnóstico por imagem , Incisivo/anatomia & histologia , Mandíbula , Microtomografia por Raio-X/métodos , Humanos , Processamento de Imagem Assistida por Computador , Incisivo/diagnóstico por imagem
17.
Am J Phys Anthropol ; 173(2): 236-249, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32369194

RESUMO

OBJECTIVE: This study explored biological sex differences in the regional daily growth rates of human anterior enamel from modern and ancient populations in Britain. METHODS: Maxillary permanent incisors (n = 80) and canines (n = 69) from Roman, Anglo-Saxon, Medieval, and Modern day populations were analyzed using histological methods. Daily secretion rates (DSRs) were collected for inner, mid, and outer regions of cuspal and lateral enamel. Modern day samples were of known sex, archeological individuals had sex determined using standard osteological methods. Variation in DSRs between the sexes, both between and within populations, was sought using parametric and nonparametric tests. RESULTS: When all samples were pooled, there was no significant difference between males and females. Similarly no significant differences in DSRs were identified between male and females within each population. When DSRs were compared between the populations, DSRs decreased from the more ancient to the more recent populations for males, and for females. More interpopulation differences were observed in males. DISCUSSION: This study presents evidence for the relative consistency of enamel DSRs between male and female groups within each British population. Interpopulation analyses found DSRs slowed significantly between Roman and modern day populations for both sexes, with male DSRs showing the greatest variation between populations.


Assuntos
Esmalte Dentário/anatomia & histologia , Esmalte Dentário/crescimento & desenvolvimento , /estatística & dados numéricos , Antropologia Física , Dente Canino/anatomia & histologia , Feminino , História do Século XXI , História Antiga , Humanos , Incisivo/anatomia & histologia , Masculino , Odontometria , Caracteres Sexuais , Reino Unido
18.
BMC Med Imaging ; 20(1): 57, 2020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-32456620

RESUMO

BACKGROUND: Playing an instrument may promote a parafunctional behavior within the cranio-cervical-mandibular-complex with unknown repercussions. The aim of this study was to find any association between the dental inter-arch relationship and the practice of a wind or string instrument. METHODS: A sample of 77 musicians, divided in two groups of wind (n = 50) and string instrumentalists (n = 27), had a lateral cephalogram taken to compare six cephalometric parameters following the Rickett's analysis (maxilla position, mandible position, facial type, skeletal class, upper incisor and lower incisor inclination). The Fisher test was performed to compare, with a 95% statistical confidence, if both groups have similar frequency distributions for each cephalometric parameter. RESULTS: No statistical differences were found for the maxilla position, mandible position, facial type, skeletal class and upper incisor inclination. Statistical differences were found for the lower incisor inclination (p = 0.011). CONCLUSIONS: Playing a wind instrument showed to have little orthopaedic influence at the craniofacial morphology, on contrary it may influence the lower incisor inclination with its osseous base.


Assuntos
Incisivo/anatomia & histologia , Mandíbula/anatomia & histologia , Maxila/anatomia & histologia , Cefalometria , Feminino , Humanos , Masculino , Música
19.
J. oral res. (Impresa) ; 9(2): 93-97, abr. 30, 2020. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-1151849

RESUMO

Objective: To determine regression models to predict the mesiodistal widths of the maxillary anterior teeth from interalar width of the nose in subjects with facial harmony. Materials and Methods: A cross-sectional study was carried out in a sample of 75 subjects with facial harmony and ages ranging from 18 to 30 years (21.28±3.75 years). The mesiodistal width of the central (CI), lateral (LI) incisors, and canines (C), as well as the interalar width (IW) of each subject were measured using a digital vernier caliper. Simple linear regression analyses were used to predict the width of the maxillary anterior teeth from the nasal interalar width, from which formulas for predicting the dimensions of each anterior tooth were obtained. Results: A statistically significant relationship was found between the nasal interalar width and the mesiodistal widths of the upper central incisor (p=0.019, R2=5.23%), upper lateral incisor (p=0.019, R2=2.31%), and upper canine (p=0.016, R2=12.04%) that allowed to develop simple linear prediction models for each tooth represented by the following formulas: CI=7.04+0.04(IW); LI=6.01+0.03 (IW); C=6.19+0.05 (IW). Conclusion: The nasal interalar width is a good predictor of the mesiodistal widths of the maxillary anterior teeth.


Objectivo: Determinar modelos de regresión para predecir los anchos mesiodistales de los dientes anterosuperiores a partir del ancho interalar de la nariz en individuos con armonía facial. Materiales and Métodos: Se realizó un estudio transversal con una muestra de 75 sujetos con armonía facial entre 18 a 30 años (21.28 ± 3.75 años), se midió el ancho mesiodistal de incisivos centrales (IC), laterales (IL) y caninos (C) así como el ancho interalar (AI) de cada sujeto empleando un calibrador vernier digital. Para la predicción del ancho de los dientes anterosuperiores a partir del ancho interalar nasal se emplearon análisis de regresión lineal simple, a partir de los cuales se obtuvieron fórmulas de predicción de las dimensiones de cada pieza dentaria anterior. Resultados: Se encontró relación estadísticamente significativa entre el ancho interalar nasal y los anchos mesiodistales del incisivo central superior (p=0.019, R2 5.23%), incisivo lateral superior (=0.019, R2=2.31%) y canino superior (p=0.016, R2=12.04%) que permitieron generar modelos de predicción lineal simple para cada pieza dentaria representados mediante las siguientes fórmulas: IC=7.04+0.04(AI); IL=6.01+0.03(AI); C=6.19+0.05(AI). Conclusión:El ancho interalar nasal es un buen predictor de los anchos mesiodistales de los dientes anterosuperiores.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Adulto Jovem , Nariz/anatomia & histologia , Dente Canino/anatomia & histologia , Incisivo/anatomia & histologia , Maxila/anatomia & histologia , Peru , Modelos Lineares , Estudos Transversais , Análise de Regressão
20.
BMJ Case Rep ; 13(3)2020 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-32169975

RESUMO

Mandibular incisors show variations in their root canal anatomy from regular pattern in some cases. Magnification plays a vital role to identify those unusual canal morphologies. A certain modification in access cavity preparation is required to locate those extra canals. Not only the functional restoration but also aesthetic harmony should be restored while treating anterior teeth. In these cases, post space preparation should be done with extra care to prevent vertical root fracture. This case report illustrates the importance of proper radiograph and magnification in the successful identification and management of complex canal systems in mandibular incisors.


Assuntos
Resinas Acrílicas/uso terapêutico , Resinas Compostas/uso terapêutico , Cavidade Pulpar/diagnóstico por imagem , Incisivo/lesões , Poliuretanos/uso terapêutico , Fraturas dos Dentes/diagnóstico por imagem , Coroas/normas , Cavidade Pulpar/anatomia & histologia , Estética , Humanos , Incisivo/anatomia & histologia , Masculino , Traumatismos Mandibulares/complicações , Radiografia/métodos , Tratamento do Canal Radicular/métodos , Fraturas dos Dentes/terapia , Raiz Dentária/anatomia & histologia , Resultado do Tratamento , Adulto Jovem
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