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1.
BMC Oral Health ; 24(1): 424, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38582881

RESUMO

INTRODUCTION: Neodymium-iron-boron magnets have been suggested as a contemporary method for accelerating the process of orthodontic tooth movement (OTM). A limited number of clinical trials evaluated their effectiveness in accelerating OTM which is desirable for both orthodontists and patients. The present study aimed to investigate the effectiveness of a low-intensity static magnetic field (SMF) in accelerating upper canine retraction movement. MATERIALS AND METHODS: Seventeen patients (mean age 20.76 ± 2.9 years) with their orthodontic treatment decision to extract the upper and lower first premolars due to bimaxillary protrusion malocclusion were included in this split-mouth study. Canine retraction was performed using Nickel-titanium (Ni-Ti) closed-coil springs (150 g of force on each side). The experimental side received SMF via an auxiliary wire that carried 4-neodymium iron-born magnets with an air gap of 2 mm between the magnets to produce a magnetic field density of 414 mT in the region corresponding to the lateral ligament of the upper canine. To determine the rate of upper canine retraction and upper molar drift, alginate impressions were taken once a month to create plaster casts, which were analyzed digitally via a three-dimensional method. RESULTS: The rate of upper canine retraction was significantly greater (P < 0.05) on the SMF side than that on the control side during the first and second months, with an overall duration (19.16%) that was greater than that on the control side. The peak acceleration occurred during the second month (38.09%). No significant differences in upper molar drift were detected between the experimental and control sides (P > 0.05). CONCLUSION: A low-intensity static magnetic field was effective at accelerating upper canine retraction. The difference between the two sides was statistically significant but may not be clinically significant. The SMF did not affect upper molar drift during the upper canine retraction phase. TRIAL REGISTRATION: The trial was retrospectively registered at the ISRCTN registry ( ISRCTN59092624 ) (31/05/2022).


Assuntos
Má Oclusão , Neodímio , Humanos , Adolescente , Adulto Jovem , Adulto , Fios Ortodônticos , Boca , Técnicas de Movimentação Dentária/métodos , Ferro , Dente Canino
2.
Sci Rep ; 14(1): 7952, 2024 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-38575623

RESUMO

To investigate the effectiveness of AcceleDent Aura vibrating device on the rate of canine retraction. Thirty-two patients requiring extraction of upper first premolars and canine retraction were randomly allocated with a 1:1 ratio into either no-appliance group or the AcceleDent Aura appliance group. Canine retraction was done applying 150gm of retraction force using NiTi coil springs on 16 × 22 stainless steel archwires. The duration of the study was 4 months. Models were collected and digitized directly after extraction of upper first premolars and at monthly intervals during canine retraction for recording the monthly as well as the total distance moved by the canine. Digitized models were superimposed on the initial model and data were statistically analyzed. Anchorage loss, rotation, tipping, torque and root condition were evaluated using cone beam computed tomography imaging. Pain was evaluated by visual analog scale. No patients were dropped-out during this study. There was no statistically significant difference between both groups regarding the total distance travelled by the canine (P = 0.436), as well as the rate of canine retraction per month (P = 0.17). Root condition was the same for the two groups. Regarding the pain level, there was no statistically significant difference between the two groups at day 0 (P = 0.721), after 24 h (P = 0.882), after 72 h (P = 0.378) and after 7 days (P = 0.964). AcceleDent Aura was not able to accelerate orthodontic tooth movement. Pain level couldn't be reduced by vibrational force with an AcceleDent device during orthodontic treatment. Root condition was not affected by the vibrational forces.


Assuntos
Epilepsia , Vibração , Humanos , Vibração/uso terapêutico , Dente Canino/diagnóstico por imagem , Técnicas de Movimentação Dentária/métodos , Dor
5.
Prim Dent J ; 13(1): 74-79, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38520194

RESUMO

Transposition of teeth may present to the general dental practitioner and in some circumstances transposed teeth may present with other dental anomalies. Although dental transpositions are rare anomalies, management of transposed teeth can often be complex, requiring multidisciplinary management. It is therefore important for dentists to be familiar with the clinical and radiographic presentation of transpositions and understand the aetiology to aid early diagnosis and appropriate management.Clinical relevance: Dentists are best placed to detect transposed teeth and should be familiar with the clinical and radiographic presentation, aetiology, and classification of transpositions in order to aid early diagnosis and their subsequent management.


Assuntos
Erupção Ectópica de Dente , Humanos , Odontólogos , Dente Canino/anormalidades , Maxila , Papel Profissional
6.
Clin Oral Investig ; 28(3): 206, 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38459220

RESUMO

OBJECTIVES: This finite element study aimed to simulate maxillary canine movement during anterior teeth retraction. MATERIALS AND METHODS: Three methods of maxillary canine movement including miniscrew sliding with high hooks (MSH), miniscrew sliding with low hooks (MSL), and the traditional sliding method (TS) without using miniscrews were simulated using three-dimensional finite element analysis. The initial displacement of the maxillary canine, the maximum principal stress of the periodontal ligament and the Von Mises stress were calculated. RESULTS: The distolingual tipping movements of the canine were shown in three movement modes. MSH showed a small tendency to lingual tipping movement and a extrusion movement while MSL had the largest lingual inclination. TS demonstrated a tendency toward distolingual torsion displacement. Compressive stress values were mainly concentrated in the range - 0.003 to -0.006 MPa. For tensile stress, the distribution of MSH and MSL was concentrated in the range 0.005 to 0.009 MPa, TS was mainly distributed about 0.003 MPa. Von Mises equivalent stress distribution showed no significant difference. CONCLUSIONS: The loss of tooth torque was inevitable, irrespective of which method was used to close the extraction space. However, miniscrew application and higher hooks reduced the loss of torque and avoided lingual rotation. CLINICAL RELEVANCE: This study shows that miniscrew implants with different hooks can better control the movement of the maxillary canines. The non-invasive nature of the finite element analysis and its good simulation of dental stress and instantaneous motion trend have a clinical advantage in the analysis of tooth movement.


Assuntos
Dente Canino , Técnicas de Movimentação Dentária , Dente Pré-Molar , Estresse Mecânico , Análise de Elementos Finitos , Torque , Técnicas de Movimentação Dentária/métodos , Maxila
7.
BMC Oral Health ; 24(1): 301, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38431628

RESUMO

BACKGROUND: This study aimed to investigate the potential associations between alveolar bone thickness, bucco-palatal inclination of maxillary lateral incisors, and lateral incisor root resorption in patients with unilateral maxillary impacted canines (UMICs). METHODS: A total of three hundred and five subjects (120 males, 185 females; mean age, 16.39 years; standard deviation, 4.04) with UMICs were included. Canine position and root resorption were assessed using CBCT. UMICs were divided into palatal, buccal and mid-alveolus groups (PICs, BICs and MAICs), with 117, 137 and 51 subjects, respectively. Alveolar bone thickness and bucco-palatal inclination of lateral incisors were measured using the Dolphin software. RESULTS: The prevalence of lateral incisor root resorption was significantly lower in the BICs (13.9%) than MAICs (29.4%) and PICs (29.1%). Alveolar bone thickness of the apical area was smaller in UMICs with lateral incisor root resorption than no resorption in both PICs (8.33 ± 1.64 vs 10.53 ± 2.55 mm) and BICs (8.94 ± 1.85 vs 10.76 ± 2.28 mm). Furthermore, lateral incisors on the impacted side were more buccally inclined in PICs with lateral incisor root resorption than no resorption, while in both BICs and MAICs, there was no statistical difference between lateral incisor root resorption than no resorption. Moreover, alveolar bone thickness of the apical area, rather than bucco-palatal inclination of lateral incisors, was significantly correlated with lateral incisor root resorption both in PICs and BICs. CONCLUSIONS: Lateral incisor root resorption is less common in BICs. Thinner alveolar bone thickness at the apical area of lateral incisors can be considered as a potential risk factor for lateral incisor root resorption in UMICs.


Assuntos
Reabsorção da Raiz , Dente Impactado , Masculino , Feminino , Humanos , Adolescente , Reabsorção da Raiz/diagnóstico por imagem , Reabsorção da Raiz/etiologia , Incisivo/diagnóstico por imagem , Tomografia Computadorizada de Feixe Cônico , Maxila/diagnóstico por imagem , Palato/diagnóstico por imagem , Dente Impactado/complicações , Dente Impactado/diagnóstico por imagem , Dente Canino/diagnóstico por imagem
8.
Angle Orthod ; 94(2): 187-193, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38381801

RESUMO

OBJECTIVES: To measure and compare labiolingual inclinations of the teeth and alveolar bone and the anterior dentoalveolar inclination in patients with skeletal Class III malocclusions with different vertical facial patterns using cone-beam computed tomography (CBCT). MATERIALS AND METHODS: Based on the inclusion and exclusion criteria, 84 CBCT images of patients with untreated skeletal Class III malocclusion were selected. There were 28 patients each in the hypo-, normo-, and hyperdivergent groups. The labiolingual inclinations of the teeth, the corresponding alveolar bone, and the anterior dentoalveolar inclinations were measured and analyzed statistically. RESULTS: The inclinations of the mandibular canine and corresponding alveolar bone were smaller in the hypodivergent group than in the hyperdivergent group. The inclination of the alveolar bone and the maxillary dentoalveolar inclination were smaller in the hyperdivergent group than in the hypodivergent group. CONCLUSIONS: There were differences in the inclination of the teeth, corresponding alveolar bone, and dentoalveolar inclinations at different positions among skeletal Class III patients with different vertical facial patterns. The roots were generally located on the labial side of the alveolar bone.


Assuntos
Má Oclusão Classe III de Angle , Humanos , Má Oclusão Classe III de Angle/diagnóstico por imagem , Face/diagnóstico por imagem , Maxila/diagnóstico por imagem , Tomografia Computadorizada de Feixe Cônico/métodos , Dente Canino/diagnóstico por imagem
9.
Gen Dent ; 72(2): 48-54, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38411485

RESUMO

The purpose of this research was to test the reliability of a modified magnification method for determining the position of an impacted canine from a single panoramic radiograph. This retrospective study evaluated 114 panoramic radiographs showing 136 impacted maxillary canines. The widths of the impacted canines, contralateral erupted canines, and ipsilateral maxillary incisors were measured, and ratios for the canine-incisor index (CII) and canine-canine index (CCI) were calculated. The impacted canines were also classified according to their location in the vertical plane (apical, middle, or coronal zone) relative to the contralateral central incisor. Continuous data were analyzed for normal distribution, and logistic and multivariate logistic regression models were conducted. The Benjamini-Hochberg procedure with a false discovery rate of 0.05 was used to account for multiple testing. The intrarater reliability was excellent for impacted canine, central incisor, and contralateral canine measurements (intraclass correlation coefficient > 0.9). The CII and vertical zone were strong predictors of an impacted canine position with clinically useful sensitivity and specificity values (0.69 and 0.74, respectively, based on an area under the curve concordance statistic of 0.75). A predictive range was evident for the CII of palatally (1.10-1.39) and buccally (0.90-1.19) impacted canines in the middle and coronal zones, respectively. The occurrence of palatal or buccal positioning was not significantly associated with the CCI (P = 0.2). The CII and vertical zone identified from a single panoramic radiograph can be used to determine the buccopalatal position of an impacted canine, with more reliability if the impacted canine crown is in the middle or coronal zone of the contralateral central incisor.


Assuntos
Dente Impactado , Humanos , Radiografia Panorâmica , Reprodutibilidade dos Testes , Estudos Retrospectivos , Dente Impactado/diagnóstico por imagem , Dente Canino/diagnóstico por imagem
10.
Sci Prog ; 107(1): 368504241228077, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38359866

RESUMO

BACKGROUND: Orthodontic treatment planning for an impacted canine tooth requires accurate information about its position. The aim of this study was to compare the diagnostic accuracy of two conventional orthodontic radiographic modalities with cone-beam computed tomography (CBCT) for localization of impacted maxillary canine teeth. MATERIALS AND METHODS: Panoramic radiographs, lateral cephalograms, and CBCT scans of 30 patients with unilaterally impacted maxillary canine teeth were retrieved from the archives. Eight expert orthodontists evaluated the parameters related to the location of impacted canine teeth by using panoramic radiographs and lateral cephalograms of patients. After 4 weeks, the same parameters were evaluated on CBCT scans of patients. The diagnostic accuracy of conventional modalities and CBCT was compared with each other and also with the gold standard. RESULTS: The conventional radiographic modalities and CBCT had similar accuracy for assessment of the overall inclination (p = 0.11), apex morphology (p = 0.18), and mesiodistal position of the apex (p = 0.12). CBCT had significantly higher accuracy for determination of incisal tip location (p = 0.001), labiopalatal (p = 0.001) and vertical (p = 0.01) position of the crown tip, minimum bone thickness covering the crown (p = 0.001), and root resorption of the adjacent tooth (p = 0.001). CONCLUSION: The combination of panoramic radiographs and lateral cephalograms was sufficiently accurate to assess some diagnostic parameters such as overall inclination, apex morphology, and mesiodistal apex location of impacted canine teeth.


Assuntos
Dente Canino , Dente Impactado , Humanos , Dente Canino/diagnóstico por imagem , Imageamento Tridimensional/métodos , Incisivo , Maxila/diagnóstico por imagem , Dente Impactado/diagnóstico por imagem , Tomografia Computadorizada de Feixe Cônico/métodos
11.
Dentomaxillofac Radiol ; 53(3): 173-177, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38374464

RESUMO

OBJECTIVES: Automating the digital workflow for diagnosing impacted canines using panoramic radiographs (PRs) is challenging. This study explored feature extraction, automated cropping, and classification of impacted and nonimpacted canines as a first step. METHODS: A convolutional neural network with SqueezeNet architecture was first trained to classify two groups of PRs (91with and 91without impacted canines) on the MATLAB programming platform. Based on results, the need to crop the PRs was realized. Next, artificial intelligence (AI) detectors were trained to identify specific landmarks (maxillary central incisors, lateral incisors, canines, bicuspids, nasal area, and the mandibular ramus) on the PRs. Landmarks were then explored to guide cropping of the PRs. Finally, improvements in classification of automatically cropped PRs were studied. RESULTS: Without cropping, the area under the curve (AUC) of the receiver operating characteristic (ROC) curve for classifying impacted and nonimpacted canine was 84%. Landmark training showed that detectors could correctly identify upper central incisors and the ramus in ∼98% of PRs. The combined use of the mandibular ramus and maxillary central incisors as guides for cropping yielded the best results (∼10% incorrect cropping). When automatically cropped PRs were used, the AUC-ROC improved to 96%. CONCLUSIONS: AI algorithms can be automated to preprocess PRs and improve the identification of impacted canines.


Assuntos
Inteligência Artificial , Dente Impactado , Humanos , Radiografia Panorâmica , Dente Impactado/diagnóstico por imagem , Curva ROC , Dente Canino/diagnóstico por imagem , Maxila/diagnóstico por imagem
12.
São Paulo; s.n; 20240222. 102 p.
Tese em Português | LILACS, BBO - Odontologia | ID: biblio-1531948

RESUMO

O presente estudo teve como objetivo avaliar a determinação do sexo por meio da análise geométrica e de mensurações a partir de imagens tridimensionais de dentes caninos, advindas de escaneamento intraoral, no Autodesk MeshMixer, bem como elaborar um roteiro prático para servir de guia na manipulação e coleta de dados nesse software. Trata-se de um estudo do tipo cego e transversal, dividido em duas etapas. Inicialmente, foram selecionadas imagens de 127 caninos (65 femininos e 63 masculinos) para a análise morfométrica geométrica, utilizando a marcação de 50 pontos, distribuídos em 27 pontos para contorno e 23 pontos para delimitação da forma das superfícies vestibular e lingual. Cada ponto de referência recebeu um valor para as coordenadas x, y e z, representando a sua posição. Na análise estatística dos dados foi utilizado um software específico para análise morfométrica geométrica, o MorphoJ, no qual foram importados os dados e submetidos à Análise Ajustada de Procrustes, Análise Discriminante e Análise da Variação Canônica. Não foram exibidas diferenças significativas para distribuição do sexo nas analises anteriores. Ainda, os dados relativos ao tamanho do centroide gerado no MorphoJ foram importados para o IBM SPSS Statistics 22.0 e submetidos ao teste t student, resultando em uma diferença estatística para o sexo. Para a aplicabilidade das mensurações digitais, foram utilizadas imagens de 345 caninos (191 femininos e 154 masculinos). Foram realizadas medidas das distâncias mesiodistais, vestibulolinguais, cervicoincisais (altura) e distâncias intercaninas de 5 pontos estabelecidos em cada canino (cúspide, cervical por vestibular e lingual, ponto máximo mesial e lingual). Todas as médias foram maiores para o sexo masculino e, com exceção da altura do elemento 33, apresentaram diferenças significativas para o sexo (p<0,05). As mensurações mesiodistais, vestibulolinguais e intercaninas (com exceção do ponto cervical por lingual), apresentaram uma boa acurácia, representadas por valores de áreas sobre a curva ROC maiores do que 0,7. O Autodesk MeshMixer apresentou-se como um ótimo auxiliar e de grande contribuição para análises dentro da Antropologia Forense. Apesar dos caninos serem elementos altamente dimórficos, para a análise morfométrica, não foram exibidas diferenças estatísticas na análise discriminante. Porém, o tamanho do centroide apresentou diferenças estatísticas e com médias maiores para o sexo masculino. As medidas realizadas nos dentes caninos apresentaram diferenças estatísticas para o sexo, com boas classificações na análise discriminante e com boas predições sexuais de acordo com os valores de especificidade e sensibilidade. A aplicabilidade de técnicas digitais de mensuração exibiu bons resultados, concordando esses dados obtidos com estudos que utilizaram as técnicas manuais de medida.


Assuntos
Análise para Determinação do Sexo , Antropologia Forense , Dente Canino , Imageamento Tridimensional
13.
BMC Oral Health ; 24(1): 194, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38321411

RESUMO

BACKGROUND: Teeth can be a reasonable part of sex estimation in case of being the single evidence available or in doubt although they are not as accurate as bones in sex estimation. The size of teeth is greater in males than in females. In this study, it was aimed to determine cut-off values of the tooth volume (TV) and root volume (RV) of the maxillary canines and to evaluate the validity of the method for discriminating between males and females. METHODS: Cone beam computed tomography (CBCT) images of 250 individuals aged 18 to 63 years with equal age and sex distribution were assessed retrospectively. The sample divided into reference set including 168 images of 84 females and 84 males and validation set including 82 images of 48 females and 34 males. Receiver operating characteristic (ROC) curve analysis, and Youden's index were used to determine cut-off values of the volumetric measurements and to test the discriminative performance of the method. RESULTS: The optimal cut-off values of TV ≥ 581 mm3 and RV ≥ 334 mm3 for estimating sex were established from the reference set. The sensitivity (Se), specificity (Sp), and accuracy (Ac) were 0.77 for TV ≥ 581 mm3 while they were 0.82, 0.77, and 0.79 for RV ≥ 334 mm3. When we tested the previously derived cut-off values of TV of the maxillary canine, the Se, Sp, and Ac were found to be respectively 0.71, 0.90, and 0.82 for TV ≥ 619 mm3 and 0.97, 0.27, and 0.56 for TV ≥ 510 / 460 mm3 (right/left). CONCLUSIONS: The identified cut-off values of TV and RV of the maxillary canines can be used to estimate sex with moderate accuracy when the only evidence available is teeth or in case of doubt. The method's applicability should be assessed for different populations.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Dente Canino , Masculino , Feminino , Humanos , Estudos Retrospectivos , Tomografia Computadorizada de Feixe Cônico/métodos , Osso e Ossos , Distribuição por Sexo , Maxila
14.
Crit Rev Biomed Eng ; 52(2): 27-37, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38305276

RESUMO

A good tooth cusp extraction is helpful in evaluating the effect of cosmetic dental work in virtual tooth surgery. We propose a new tooth cusp extraction, which integrates the DBSCAN (density-based spatial clustering of applications with noise) clustering algorithm with the neighborhood search algorithm to extract tooth cusp from a three-dimensional cloud-point tooth model. This method used the point cloud height and curvature to screen out the dented point set. Then we employ the DBSCAN clustering algorithm to segment different feature regions of the tooth surface and generate the candidate point set. Finally, the candidate point set was accurately located at the tooth apex through the neighborhood search algorithm and the traversal search method of non-maximum suppression. The experimental results show that the proposed method is superior to the traditional watershed algorithm-based methods by calculating the recall rate and accuracy rate, and also has higher extraction speed and extraction precision than manual extraction methods.


Assuntos
Algoritmos , Dente Canino , Extração Dentária , Humanos , Análise por Conglomerados
15.
Eur J Paediatr Dent ; 25: 1, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38329027

RESUMO

BACKGROUND: The proper development of the dental arches, including the eruption and correct positioning of the canines in the arch, is essential for the oral health of growing patients. Impacted canines not only give rise to functional challenges but also pose esthetic issues for patients. The aim of this article is to show if it is possible to benefit from the exclusive use of transparent aligners to guide the eruption of ectopic upper canines into the arch in the correct position. CASE REPORT: The subject of the study is the clinical case of a 13-year-old female growing patient who presented displaced upper permanent canines located in the palatal ectopic site. Following the surgical extraction of the retained deciduous elements, treatment with aligners for repositioning the ectopic canines in the arch was performed in two phases. At the end of the treatment, a Class I canine was achieved with satisfactory repositioning of the upper canines in the arch. CONCLUSION: The use of transparent aligners makes it possible, with some procedural precautions and in carefully selected cases, to reposition the ectopic palatal canines in the dental arch using a treatment that is both esthetic and effective.


Assuntos
Aparelhos Ortodônticos Removíveis , Erupção Ectópica de Dente , Dente Impactado , Feminino , Humanos , Adolescente , Erupção Ectópica de Dente/cirurgia , Erupção Dentária , Palato , Maxila , Dente Impactado/cirurgia , Dente Canino/cirurgia
16.
Dentomaxillofac Radiol ; 53(1): 60-66, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38214943

RESUMO

OBJECTIVES: This study aims to evaluate the morphological features of gubernacular tract (GT) for erupting permanent mandibular canines at different ages from 5 to 9 years old with a three-dimensional (3D) measurement method. METHODS: The cone-beam CT images of 50 patients were divided into five age groups. The 3D models of the GT for mandibular canines were reconstructed and analysed. The characteristics of the GT, including length, diameter, ellipticity, tortuosity, superficial area, volume, and the angle between the canine and GT, were evaluated using a centreline fitting algorithm. RESULTS: Among the 100 GTs that were examined, the length of the GT for mandibular canines decreased between the ages of 5 and 9 years, while the diameter increased until the age of 7 years. Additionally, the ellipticity and tortuosity of the GT decreased as age advanced. The superficial area and volume exhibited a trend of initially increasing and then decreasing. The morphological variations of the GT displayed heterogeneous changes during different periods. CONCLUSIONS: The 3D measurement method effectively portrayed the morphological attributes of the GT for mandibular canines. The morphological characteristics of the GT during the eruption process exhibited significant variations. The variations in morphological changes may indicate different stages of mandibular canine eruption.


Assuntos
Maxila , Erupção Dentária , Humanos , Pré-Escolar , Criança , Tomografia Computadorizada de Feixe Cônico/métodos , Dente Canino/diagnóstico por imagem
17.
BMC Res Notes ; 17(1): 12, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38167562

RESUMO

OBJECTIVE: While mixed dentition space analysis is a common practice in pediatric dentistry, digital models created using an intraoral scanner are not as widely used in clinical settings. This preliminary study used a very small sample size with one reference model and aimed to (1) compare the accuracy of mixed dentition space analysis using a digital model obtained from an optical impression with that of conventional plaster model-based analysis and (2) assess inter-examiner differences. RESULTS: The space required for the mandibular permanent canine and premolars and arch length discrepancy were calculated using each model. The largest significant difference between plaster- and digital model-based analyses was identified when the right arch length discrepancy was considered (-0.49 mm; 95% confidence interval: -0.95-0.03); however, the value was considered clinically insignificant. Significant inter-examiner differences were observed for six items of the plaster model; however, no such differences were observed when using the digital model. In conclusion, digital model space analysis may have the same level of accuracy as conventional plaster model analysis and likely results in smaller inter-examiner differences than plaster model analysis.


Assuntos
Dentição Mista , Imageamento Tridimensional , Criança , Humanos , Imageamento Tridimensional/métodos , Reprodutibilidade dos Testes , Modelos Dentários , Dente Canino , Arco Dental/diagnóstico por imagem , Desenho Assistido por Computador
18.
Sci Rep ; 14(1): 369, 2024 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172136

RESUMO

The process of creating virtual models of dentomaxillofacial structures through three-dimensional segmentation is a crucial component of most digital dental workflows. This process is typically performed using manual or semi-automated approaches, which can be time-consuming and subject to observer bias. The aim of this study was to train and assess the performance of a convolutional neural network (CNN)-based online cloud platform for automated segmentation of maxillary impacted canine on CBCT image. A total of 100 CBCT images with maxillary canine impactions were randomly allocated into two groups: a training set (n = 50) and a testing set (n = 50). The training set was used to train the CNN model and the testing set was employed to evaluate the model performance. Both tasks were performed on an online cloud-based platform, 'Virtual patient creator' (Relu, Leuven, Belgium). The performance was assessed using voxel- and surface-based comparison between automated and semi-automated ground truth segmentations. In addition, the time required for segmentation was also calculated. The automated tool showed high performance for segmenting impacted canines with a dice similarity coefficient of 0.99 ± 0.02. Moreover, it was 24 times faster than semi-automated approach. The proposed CNN model achieved fast, consistent, and precise segmentation of maxillary impacted canines.


Assuntos
Aprendizado Profundo , Dente Impactado , Humanos , Tomografia Computadorizada de Feixe Cônico/métodos , Dente Canino/diagnóstico por imagem , Redes Neurais de Computação , Processamento de Imagem Assistida por Computador/métodos
19.
Clin Oral Investig ; 28(1): 95, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38221544

RESUMO

OBJECTIVES: To comparatively assess 3 interproximal reduction (IPR) methods used in clear aligner treatment with regard to accuracy, and patient perception of discomfort and anxiety. MATERIALS AND METHODS: A total of 42 patients, treated with the Invisalign® system, were included in this prospective trial and received one of the following IPR methods: hand-operated abrasive strips (group 1; 14 patients, 150 teeth), motor-driven 3/4 oscillating segmental discs (group 2; 14 patients, 134 teeth), or motor-driven abrasive strips (group 3; 14 patients, 133 teeth). Accuracy was evaluated using the difference between planned and executed IPR. Anxiety and discomfort levels experienced by the patients were evaluated using a questionnaire of 17 questions. RESULTS: The accuracy of IPR was high in groups 2 and 3; however, it was low in group 1 with the executed IPR significantly less than the planned amount. On quadrant-level, executed IPR was significantly less in the upper left quadrant in group 1, and significantly more in the upper right quadrant in group 2. The difference between planned IPR and executed IPR was significant for teeth 11, 21, 32, 33, and 43 in group 1, indicating deficiency. The average difference between planned IPR and executed IPR was 0.08 mm for group 1, 0.09 mm for group 2, and 0.1 mm for group 3. Anxiety and discomfort levels did not differ between the methods, but a negative correlation was observed between age and discomfort and anxiety levels. CONCLUSIONS: The overall accuracy of the 2 motor-driven IPR methods was found to be better than the hand-operated system. Maxillary central incisors and mandibular canines were more prone to IPR deficiency when hand-operated abrasive strips were utilized. Patients were similarly comfortable with all 3 methods, and discomfort and anxiety levels decreased with age. CLINICAL RELEVANCE: Motor-driven methods have proven to be more effective when compared to the hand-operated ones by means of precision, speed, and patient comfort. If the clinician favors a hand-operated method, it may be advised to perform slightly more IPR especially on mandibular canines and maxillary central incisors.


Assuntos
Incisivo , Aparelhos Ortodônticos Removíveis , Humanos , Dente Canino , Cabeça , Estudos Prospectivos
20.
Int J Legal Med ; 138(2): 451-465, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37861739

RESUMO

The age estimation of an adult using methods accessible to the forensic routine is a goal pursued by forensic experts. Cameriere, Ferrante and Cingolani (2004) proposed the use of the pulp/tooth area ratio of canine teeth as a promising variable, but its reliability has shown conflicting results in the scientific literature. This article aimed to carry out a systematic review with meta-analysis to verify whether the pulp/tooth area ratio of canine teeth includes a variable that can be used alone to estimate dental age in adults. A systematic search was carried out in six databases using keywords related to the theme in Portuguese, English, and Spanish. The study selection process followed pre-established eligibility criteria. Assessments were carried out regarding risk of bias and publication bias of selected studies, and meta-analysis was carried out considering Pearson's correlation coefficient between pulp/tooth area ratio and chronological age as effect measure. Most selected studies showed low risk of bias; no publication bias was found when all studies were considered, and potential publication bias was found when outliers were removed. Despite the high heterogeneity among studies and the need for more research, it could be observed that the pulp/tooth area ratio has strong negative correlation with chronological age, and the pulp/tooth area ratio could be derived from both periapical radiographs and orthopantomographs. Therefore, it is suggested that there is scientific evidence that the pulp/tooth area ratio obtained from canine teeth is reliable for dental age estimation in adults.


Assuntos
Determinação da Idade pelos Dentes , Dente Canino , Adulto , Humanos , Dente Canino/diagnóstico por imagem , Dente Canino/anatomia & histologia , Reprodutibilidade dos Testes , Determinação da Idade pelos Dentes/métodos , Radiografia Panorâmica , Etnicidade , Polpa Dentária/diagnóstico por imagem
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