RESUMO
O objetivo do presente estudo foi avaliar em tomografias computadorizadas as dimensões dos tecidos periodontais supracrestais (TPSC). Cem pacientes, 600 dentes anteriores da maxila (200 incisivos centrais, 200 incisivos laterais e 200 caninos), foram avaliados. A distância média da margem gengival até a crista óssea alveolar (COA) foi de 3.25mm (95% IC: 3.20-3.30), enquanto que da junção cemento-esmalte até a COA foi de 1.77mm (95% IC: 1.72-182mm). As medidas foram significativamente diferentes entre os grupos de dentes (ANOVA, p < 0.001). A tomografia, pode representar uma importante ferramenta para a avaliação das dimensões dos TPSC.
The aim of this study was to evaluate the dimensions of the supracrestal periodontal tissues (SPT) on tomographic scans. One hundred patients, 600 maxillary anterior teeth (200 central incisors, 200 lateral incisors and 200 canines), were evaluated. The average distance from the gingival margin to the alveolar bone crest (ABC) was 3.25mm (95% CI: 3.20-3.30), while the distance from the cemento-enamel junction to ABC was 1.77mm (95% CI: 1.72-182mm). The measurements were significantly different between the tooth groups (ANOVA, p < 0.001). When properly indicated, tomography can be an important tool for assessing the dimensions of TPSCs on a case-by-case basis.
Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Adulto Jovem , Tecidos , Periodonto , Tomografia Computadorizada de Feixe Cônico , MaxilaRESUMO
Este estudo teve como objetivo avaliar o dimorfismo sexual em uma coleção de mandíbulas portuguesas através de uma metodologia métrica digital, utilizando análise estatística descritiva, inferencial e multivariada para identificar quais parâmetros são mais dimórficos e quais são os melhores preditores de sexo. Trinta e três mandíbulas (14 mulheres e 19 homens) e pertences pessoais foram fotograficamente registrados com código e sexo. Os dados foram coletados por tomografia e as medidas foram feitas pelo software Simplant Pro. Foram registrados a largura máxima e mínima do ramo mandibular, altura condilar, altura do processo coronoide, altura da sínfise mandibular, ângulo mandibular, distâncias bimentual, biantegonial, bigonial e bicondilar e comprimento máximo mandibular. A análise estatística foi realizada utilizando IBM® SPSS. Os resultados mostraram diferenças estatisticamente significativas para os seguintes parâmetros: altura do processo coronoide, altura do côndilo, comprimento máximo da mandíbula e largura mínima do ramo mandibular. Na análise estatística multivariada foi possível identificar a altura do processo coronoide como melhor preditor de sexo com precisão em 72,2% dos casos. Isto permite uma diferenciação mais fácil entre mandíbulas femininas e masculinas com uma precisão de 64,3% e 78,9%, respectivamente. Foi possível concluir que a altura do processo coronoide é o parâmetro mais dimórfico e o melhor preditor de sexo na amostra.
This study aimed to assess sex dimorphism in a collection of Portuguese mandibles through a digital metric methodology by using descriptive, inferential, and multivariate statistical analysis to identify which parameters are the most dimorphic and which are the best sex predictors. Thirty-three mandibles (14 females and 19 males) and personal belongings were photographically registered with code and sex. Data was collected using tomography, and measurements were made using the Simplant Pro software. The maximum and minimum width of the mandibular ramus, condylar height, coronoid process height, mandibular symphysis height, mandibular angle, bi-mental, bi-antegonial, bi-gonial and bi-condylar distances, and maximal mandibular length were registered. Statistical analysis was performed using IBM® SPSS. The results showed statistically significant differences for the following parameters: coronoid process height, condyle height, the maximum length of the mandible, and the minimum width of the mandibular ramus. In the multivariate statistical analysis, it was possible to identify the coronoid process height as the best sex predictor accurately in 72.2% of cases. This allows for easier differentiation between female and male mandibles with an accuracy of 64.3% and 78.9%, respectively. It was possible to conclude that the coronoid process height is the most dimorphic parameter and the best sex predictor in the sample.
Assuntos
Humanos , Masculino , Feminino , Caracteres Sexuais , Diagnóstico , Tomografia Computadorizada de Feixe Cônico , MandíbulaRESUMO
INTRODUCTION: Alveolar bone coverage can be diagnosed through cone beam computed tomography (CBCT) and this information can prevent orthodontic tooth movement beyond the biological limit. OBJECTIVE: This study evaluated the impact of the bone coverage (BC) diagnosis by CBCT in the orthodontists' planning. METHODS: One hundred fifty-nine Brazilian orthodontists suggested treatment plans for six patients at two different times, using two sequential questionnaires. The first questionnaire consisted of extra and intra-oral photographs, one panoramic radiograph; one lateral cephalometric radiograph with Steiner and Tweed analysis, and the patient chief complaint. The second questionnaire included the same presentations of cases with tomographic images and the radiologist's report. The McNemar test assessed the difference between the first and the second treatment plans. RESULTS: In all six cases, most participants changed the treatment plan after evaluating the CBCT images and the radiologist's report (93.7% in case 5, 78.6% in case 4, 74.2% in case 3, 69.8% in case 6, 66% in case 2 and 61% in case 1; p≤0.01). CONCLUSION: The evaluation of bone coverage through CBCT images has a substantial impact on the orthodontic diagnosis and planning of the Brazilian orthodontists.
Assuntos
Processo Alveolar , Tomografia Computadorizada de Feixe Cônico , Planejamento de Assistência ao Paciente , Radiografia Panorâmica , Humanos , Estudos Transversais , Processo Alveolar/diagnóstico por imagem , Brasil , Cefalometria , Inquéritos e Questionários , Feminino , Masculino , Ortodontistas , Técnicas de Movimentação Dentária , Ortodontia CorretivaRESUMO
INTRODUCTION: The long pathway that the canines take as they emerge into the maxillary arch makes them vulnerable to disruption during their natural emergence time. The process of planning treatment for impacted maxillary canine (IMC) presents significant challenges, underscoring the need for careful consideration and expertise. OBJECTIVE: The aim of this article was to shed light on these complexities by discussing clinical case studies involving IMC, providing insights into the intricacies of their management. CONCLUSIONS: The management of IMC within orthodontics presents a multifaceted challenge that include the necessity for precise diagnostic processes, prudent use of cone beam computed tomography (CBCT), the strategic selection between open and closed exposure techniques, a in-depth understanding of the specific orthodontic biomechanics involved, and a keen awareness of potential adverse outcomes such as ankylosis, prolonged treatment times, root resorption, and additional complications.
Assuntos
Tomografia Computadorizada de Feixe Cônico , Dente Canino , Maxila , Dente Impactado , Dente Impactado/terapia , Dente Impactado/diagnóstico por imagem , Humanos , Dente Canino/diagnóstico por imagem , Maxila/diagnóstico por imagem , Planejamento de Assistência ao Paciente , Extrusão Ortodôntica/métodos , Reabsorção da Raiz/diagnóstico por imagem , Reabsorção da Raiz/terapia , Feminino , Adolescente , Fenômenos Biomecânicos , Masculino , Anquilose Dental/terapia , Anquilose Dental/diagnóstico por imagem , Criança , Técnicas de Movimentação Dentária/métodosRESUMO
OBJECTIVES: To assess the effective and organ/tissue equivalent radiation doses of different scout projection protocols in four CBCT units. METHODS: Optically stimulated luminescence dosimeters (OSLD) were placed in reference anatomical locations in the head and neck segments of an anthropomorphic phantom representing an average adult male. Ten repeated exposures were obtained from each of the twelve scout projections studied, acquired from four maxillofacial cone beam computed tomography (CBCT) units (Midmark EIOS, 3D Accuitomo F170, Veraviewepocs 3D R100, and Veraview X800). The effective and organ/tissue equivalent doses were calculated for each protocol. RESULTS: Effective doses ranged from 0.7 µSv (Accuitomo F170 60 × 60 mm-anterior maxilla) to 6.9 µSv (Midmark 50 × 50 mm-anterior maxilla). The highest organ/tissue equivalent doses were recorded for the oral mucosa and salivary glands; however, the thyroid was the highest contributor to the effective dose, followed by the salivary glands. CONCLUSIONS: Despite some variability among CBCT machines and protocols, the acquisition of scout projections is a low-dose procedure. The use of scout projections to ensure an adequate position of the region of interest within the field of view is highly desirable as they contribute minimally to overall CBCT patient dose.
Assuntos
Tomografia Computadorizada de Feixe Cônico , Imagens de Fantasmas , Doses de Radiação , Tomografia Computadorizada de Feixe Cônico/métodos , Humanos , Masculino , Adulto , Dosimetria por Luminescência Estimulada Opticamente/métodosRESUMO
Comprehensively evaluating molar incisor hypomineralisation (MIH) involves the integration of anamnesis and clinical data to diagnose, create a care plan, and predict prognoses. Anamnesis reveals relationships between defects and time, patient expectations, and impacts on the quality of life. Clinical studies emphasize posteruptive breakdown in yellow-brown opacities, highlighting the importance of identifying risk factors. The classification and recording of the clinical features associated with MIH are essential and allow for the longitudinal follow-up of the patient. Assessment of dental caries lesions, oral hygiene, and pain guides the care plan. Depending on the severity of MIH and associated symptoms, intraoral radiographs and cone beam computed tomography may be necessary. In cases of scheduled extractions, extraoral radiographs, photographs, and study models are indicated. Evaluations of the quality of life, aesthetic perception, and dental fear and anxiety provide valuable insights into the patient's emotional status and guide empathetic practice. A positive dental experience is based on communication with the patient, trust, and the proper use of behavior guidance techniques.
Assuntos
Qualidade de Vida , Humanos , Hipoplasia do Esmalte Dentário/diagnóstico , Tomografia Computadorizada de Feixe Cônico , Higiene Bucal , Hipomineralização MolarRESUMO
This study employed e-Vol DXS cone beam computed tomography (CBCT) software to assess dentin remnants in the furcation area of mesial canals in mandibular molars during root canal retreatment (RCR). Four groups (Reciproc®, ProTaper Next®, Race Evo®, Protaper Gold®) were subjected to RCR, and CBCT images were captured before (T1) and after (T2) treatment. Measurements of remaining dentin thickness at 1 mm and 3 mm below the furcation were scrutinized. Results revealed no significant differences in mean thicknesses of mesiobuccal (MB) and mesiolingual (ML) canals at 1 mm and 3 mm from the furcation pre-treatment (T1). Post-treatment (T2) showed analogous findings, with no significant differences in mean thicknesses. However, disparities were found between MB and ML canals at both distances, both before and after retreatment. In essence, the evaluated instruments exhibited safety in RCR, implying that they are appropriate for use in critical areas of mandibular molars without inducing excessive wear. This study underscores the reliability of these instruments in navigating danger zones during RCR, and contributes valuable insights for dental practitioners who handle complex root canal scenarios in mandibular molars.
Assuntos
Tomografia Computadorizada de Feixe Cônico , Cavidade Pulpar , Dentina , Mandíbula , Dente Molar , Retratamento , Humanos , Tomografia Computadorizada de Feixe Cônico/métodos , Dente Molar/diagnóstico por imagem , Dente Molar/anatomia & histologia , Retratamento/métodos , Mandíbula/diagnóstico por imagem , Mandíbula/anatomia & histologia , Reprodutibilidade dos Testes , Cavidade Pulpar/diagnóstico por imagem , Cavidade Pulpar/anatomia & histologia , Dentina/diagnóstico por imagem , Instrumentos Odontológicos , Tratamento do Canal Radicular/métodos , Tratamento do Canal Radicular/instrumentação , Valores de Referência , Preparo de Canal Radicular/instrumentação , Preparo de Canal Radicular/métodos , Desenho de Equipamento , Estatísticas não ParamétricasRESUMO
This study aimed to assess the relationship between Schneiderian membrane thickening and periapical pathology in a retrospective analysis of Cone Beam Computed Tomography (CBCT) images. For this, 147 CBCT scans containing 258 sinuses and 1,181 teeth were assessed. Discontinuation of the lamina dura, widening of the periodontal ligament space, apical periodontitis (AP), and partly demineralized maxillary sinus floor associated with AP were considered periapical pathology. Maxillary sinus mucosal thickening (MSMT) was classified as odontogenic or non-odontogenic. An irregular band with a focal tooth associated thickening and local thickening related to a root were considered odontogenic types of MSMT. The relation between the imaging features of periapical pathology and the type and thickness of MSMT was determined by logistic regression and linear mixed model, respectively. In addition, linear regression and Mann Whitney test evaluated the relation and demineralization of the AP lesion towards the sinus floor (p≤0.05). The odds of having an odontogenic type of MSMT were significantly higher when a periapical pathology was present in the maxillary sinus. Eighty-two percent of AP partly demineralized towards the sinus floor were associated with an odontogenic MSMT. Both AP lesions partly demineralized towards the sinus floor and, with increased diameter, led to increased MSMT. In conclusion, there is an 82% risk of having an odontogenic type of MSMT with the presence of AP partly demineralized towards the sinus floor. More thickening of the maxillary sinus mucosa is seen with larger AP lesions and partial demineralization of the sinus floor.
Assuntos
Tomografia Computadorizada de Feixe Cônico , Mucosa Nasal , Humanos , Tomografia Computadorizada de Feixe Cônico/métodos , Estudos Retrospectivos , Mucosa Nasal/diagnóstico por imagem , Mucosa Nasal/patologia , Feminino , Masculino , Pessoa de Meia-Idade , Doenças Periapicais/diagnóstico por imagem , Doenças Periapicais/patologia , Adulto , Seio Maxilar/diagnóstico por imagem , Seio Maxilar/patologia , Periodontite Periapical/diagnóstico por imagem , Periodontite Periapical/patologia , IdosoRESUMO
AIM: To evaluate the influence of different levels of metal artifact reduction (MAR) tool and milliamperage (mA) on the diagnosis of fracture extension in endodontically treated teeth using cone beam CT (CBCT). MATERIALS AND METHODS: Ten maxillary premolars were endodontically treated and positioned in the empty sockets of a human maxilla covered with wax. CBCT acquisitions were performed using the Eagle Edge device (Dabi Atlante, Brazil) adjusted to 120 kVp, FOV of 4 × 6 cm, exposure time of 24 s and voxel size of 0.2 mm in 8 different conditions with different MAR (1, 2 and 3) and mA (3.2 and 6.3) levels. Crown-root fractures were simulated in the universal testing machine, and CBCT images were acquired again. Five radiologists evaluated the presence and extension of fractures with a 5-point scale. Statistical analysis was performed by analysis of variance, Tukey and Kappa test (α = 0.05). RESULTS: Although different mA levels did not significantly (p > 0.05) affect the diagnosis values for fracture presence and extension, when evaluated the different levels of MAR, AUC and sensitivity showed significantly higher values (p < 0.05) for MAR 0 using 6.3 mA and kappa agreement showed significantly higher values (p < 0.05) for MAR 0 and 2 using 6.3 mA. CONCLUSIONS: Although mA levels do not have a diagnostic effect when isolating the MAR level; in 6.3 mA, MAR 0 and 2 can positively influence the diagnosis of fracture extension in endodontically treated teeth using CBCT. CLINICAL RELEVANCE: The isolate evaluation of dental fracture presence can overlook diagnostics error of its extension.
Assuntos
Artefatos , Dente Pré-Molar , Tomografia Computadorizada de Feixe Cônico , Fraturas dos Dentes , Dente não Vital , Humanos , Fraturas dos Dentes/diagnóstico por imagem , Tomografia Computadorizada de Feixe Cônico/métodos , Dente não Vital/diagnóstico por imagem , Dente Pré-Molar/diagnóstico por imagem , Dente Pré-Molar/lesões , Técnicas In Vitro , Metais , Maxila/diagnóstico por imagem , Sensibilidade e EspecificidadeRESUMO
OBJECTIVE: This study aimed to assess root volumes of maxillary canines and adjacent lateral incisors in patients with unilateral maxillary canine impaction. METHODS: This cross-sectional study was performed on cone-beam computed tomography (CBCT) scans of 100 patients (49 females and 51 males) with unilateral maxillary canine impaction. The images were loaded in Planmeca Romexis Viewer, and root layers between the cementoenamel junction and apex were reconstructed at 600-µm intervals. At each layer, the root boundary was marked, and finally, the root volume was calculated by multiplying the layers' area by the thickness of 600 µm. The root size of canines and lateral incisors was compared between the impaction and normal eruption sides. RESULTS: Sixty-two patients showed buccal canine impaction, and 38 presented palatal impaction. The mean root volume of canines on the impaction side was significantly greater than that on the normal eruption side; either the tooth was buccally or palatally impacted (p<0.001). The lateral incisors on the side of buccally-impacted canines showed a significantly smaller root volume than that of the contralateral side (p<0.001). However, there was no significant difference in the root size of lateral incisors between the two sides in cases presenting palatal canine impaction (p=0.177). CONCLUSION: The difference in root volume of canines between the two sides can serve as an indicator of canine impaction. The reduction in the root size of the lateral incisor on the side of the buccally impacted canine may be due to root resorption created by pressure from the canine's crown.
Assuntos
Tomografia Computadorizada de Feixe Cônico , Dente Canino , Incisivo , Maxila , Raiz Dentária , Dente Impactado , Humanos , Dente Impactado/diagnóstico por imagem , Masculino , Dente Canino/diagnóstico por imagem , Feminino , Incisivo/diagnóstico por imagem , Estudos Transversais , Maxila/diagnóstico por imagem , Raiz Dentária/diagnóstico por imagem , Adolescente , Adulto Jovem , Adulto , CriançaRESUMO
OBJECTIVE: To assess the effect of a blooming artifact reduction (BAR) filter on cone beam computed tomography (CBCT) images in the dimensional analysis of dental implants. STUDY DESIGN: Six types of implants (n = 5 for each type) composed of titanium (3 types), titanium-zirconia alloy, zirconium oxide, and titanium-aluminum-vanadium alloy, and made with 2 manufacturing processes (milled and printed) were individually installed in a bovine rib block according to the manufacturer's protocol. CBCT images were acquired with i-CAT and Carestream scanners, randomized, and analyzed without and with the e-Vol DX BAR filter (60 images for each scanner). Implant length, diameter, and thread-to-thread distance were measured by two radiologists, with a stereomicroscopic image of each implant as the reference standard for calculation of distortion in measurements. Repeated measures ANOVA with Bonferroni corrections and intraclass correlation coefficients (ICC) were applied (α = 0.05). RESULTS: The BAR filter significantly reduced distortion in various parameters for specific implants, aligning closely with stereomicroscopic measurements. Titanium and printed implants showed reduced dimensional distortion regardless of BAR filter use. Carestream measurements presented smaller dimensional differences than i-CAT for most implants and parameters, especially without BAR (P < .05). Interexaminer reliability was good to excellent, with ICC ranging from 0.80 to 0.95. CONCLUSIONS: The BAR filter can enhance implant dimensional analysis, although variations based on implant material and manufacturing process were observed.
Assuntos
Artefatos , Tomografia Computadorizada de Feixe Cônico , Implantes Dentários , Titânio , Animais , Bovinos , Zircônio , Interpretação de Imagem Radiográfica Assistida por Computador , Imageamento TridimensionalRESUMO
O odontoma é o mais comum tumor odontogênico, definido como malformação benigna, geralmente descoberto na segunda década de vida, durante a investigação de erupção tardia de dentes adjacentes ou retenção prolongada de dentes decíduos. O odontoma é subdividido em composto e complexo. O Odontoma classificado como Composto é constituído por um conjunto de estruturas similares a dentes, de formas e tamanhos diversos, cercados por uma área delgada radiolúcida. Já o Odontoma Complexo se assemelha a uma massa calcificada que apresenta a mesma radiopacidade do tecido dentário, também cercado por uma área delgada radiolúcida. Ocasionalmente, esses dois aspectos podem ser vistos em uma mesma lesão. Frequentemente os odontomas podem provocar um aumento de volume ósseo local devido ao seu desenvolvimento. O diagnóstico é feito através de exames radiográficos de rotina e quando necessário pode-se também lançar mão de Radiografias Panorâmicas e Tomografia Computadorizada Cone Beam com o intuito de verificar sua extensão, as malformações e alterações de erupção causadas aos dentes adjacentes, assim como a classificação do tumor. Este relato de caso apresenta um Odontoma Composto-Complexo em um paciente de 13 anos, do sexo masculino, atendido em 2016 na Clínica de Diagnóstico Bucal II da Universidade Federal Fluminense, que apresentou elementos dentários 22 e 23 impactados, retenção prolongada do elemento 63 e aumento de volume na região anterior do lado esquerdo da maxila. Para obtenção do diagnóstico foram realizadas: Radiografias Periapicais, Radiografia Panorâmica e Tomografia Computadorizada Cone Beam. O objetivo deste trabalho foi elucidar as formas de diagnóstico por imagem que foram utilizadas neste caso clínico e quais as vantagens de cada exame.
Odontomas are the most common type of odontogenic tumors, defined as a benign malformation, usually diagnosed in the second decade of life, during the investigation of late adjacent teeth eruption or a delay in exfoliation of deciduous teeth. They are divided into two types: compound and complex. The odontoma classified as compound is composed of multiple small tooth-like structures, in several shapes and sizes, surrounded by a thin radiolucent rim. On the other hand, complex odontomas resemble a mass of calcified tissue that presents the same dental tissue radiopacity, also surrounded by a thin radiolucent rim. Occasionally, both aspects can be seen in the same lesion. Often, odontomas can cause a local increase in bone volume due to their development. The diagnosis is made through routine radiographic examination and, when it is necessary, it is possible to make use of panoramic radiographies and cone beam computed tomography with the purpose of verifying its extension, malformations and erupted alterations caused to the adjacent teeth, as well as the tumor classification. This case report presents a Compound-Complex Odontoma in a 13-year-old male patient, treated in 2016 at the Oral Diagnosis Clinic II of the Federal Fluminense University. He presented impacted teeth 22 and 23, delayed eruption of tooth 63 and volume increase in the left anterior maxilla site. Aiming the patient's diagnosis, the following exams were necessary: periapical radiographies, panoramic radiography, cone beam computed tomography. The aim of this paper is to explain the different image diagnostic tools which were used in this clinical study and what are the advantages of each exam.
Assuntos
Humanos , Masculino , Adolescente , Dente Impactado , Raios X , Diagnóstico por Imagem , Radiografia Panorâmica , Odontoma , Tomografia Computadorizada de Feixe CônicoRESUMO
Guided bone regeneration involving the use of titanium mesh and platelet-rich fibrin could be a feasible approach in cases of severely atrophic ridges. The purpose of this case report was to present an esthetic and functional rehabilitation in the anterior maxilla with the installation of dental implants in conjunction with guided bone regeneration using titanium mesh and advanced platelet-rich fibrin (A-PRF). A 60-year-old patient presented bone atrophy and partial edentulism in the anterior maxilla. After clinical and cone beam computed tomography assessment, guided bone regeneration was planned using a titanium mesh and A-PRF with xenograft bone. After 8 months of healing, the dental implants were placed with the aid of a surgical guide to obtain accurate 3-dimensional positioning. Prosthetic rehabilitation was carried out with individualized crowns. After 2 years of follow-up, radiographic analysis demonstrated a good quality and density of the bone tissue adjacent to the dental implants. No radiolucent areas were observed, and there were no clinical signs of failure. In cases of severe atrophy, using a titanium mesh and A-PRF proved to be a feasible alternative for bone reconstruction prior to dental implant placement. This approach can aid dental professionals in achieving an ideal implant positioning for rehabilitation with individualized crowns.
Assuntos
Regeneração Óssea , Tomografia Computadorizada de Feixe Cônico , Maxila , Fibrina Rica em Plaquetas , Telas Cirúrgicas , Titânio , Humanos , Pessoa de Meia-Idade , Maxila/cirurgia , Seguimentos , Implantação Dentária Endóssea/métodos , Coroas , Masculino , Implantes Dentários , Regeneração Tecidual Guiada Periodontal/métodos , Arcada Parcialmente Edêntula/reabilitação , Arcada Parcialmente Edêntula/cirurgia , FemininoRESUMO
OBJECTIVES: This study evaluated the impact of variations in anteroposterior and lateral tilts of patients head on radiation-weighted doses to organs/tissues and effective doses using 3 different cone beam computed tomography (CBCT) machines. METHODS: An anthropomorphic phantom was used to estimate radiation doses in 3 CBCT machines (OP300, Eagle X 3D, and Eagle Edge). Thermoluminescent dosimeters were placed in regions corresponding to pre-stablished organ/tissues. CBCT examinations from the posterior mandible and anterior maxilla regions were acquired, with 3 different anteroposterior angulations (0°, 30°, and 45°), and from the posterior mandible in 3 different lateral angulations (0°, 20° to the left, and 20° to the right side). Radiation-weighted doses for each organ/tissue and effective doses were calculated for each machine and angulation. RESULTS: For the posterior mandible acquisitions, anteroposterior angulations of the head at 30° and 45° yielded a reduction in effective doses in all 3 devices. A 20° tilt to the right side resulted in lower doses than to the left [same side as the field of view (FOV)]. For the anterior maxilla, increased anteroposterior angulation was associated with reduction in effective dose in 2 devices. CONCLUSIONS: Effective doses are lower when small FOV CBCT exams of the posterior mandible and anterior maxilla are acquired with increased anteroposterior head angulation at 30° and 45°. For FOV in the posterior mandible, a 20° lateral tilt towards the side opposite to the FOV also yields lower effective doses. The main contribution to these dose reductions is the decrease in dose to salivary glands.
Assuntos
Tomografia Computadorizada de Feixe Cônico , Imagens de Fantasmas , Doses de Radiação , Dosimetria Termoluminescente , Tomografia Computadorizada de Feixe Cônico/métodos , Humanos , Cabeça/diagnóstico por imagem , Posicionamento do Paciente , Mandíbula/diagnóstico por imagem , Maxila/diagnóstico por imagemRESUMO
BACKGROUND: Micro-osteoperforation is a minimally invasive technique aimed at accelerating tooth movement. The goal of this novel experimental study was to assess tooth movement and stress distribution produced by the force of orthodontic movement on the tooth structure, periodontal ligament, and maxillary bone structure, with and without micro-osteoperforation, using the finite element method. MATERIALS AND METHODS: Cone-beam computed tomography was used to obtain a virtual model of the maxilla and simulate the extraction of right and left first premolars. Three micro-osteoperforations (1.5 x 5 mm) were made in the hemiarch on the distal and mesial surfaces of upper canines, according to the power tip geometry of the Propel device (Propel Orthodontics, Ossining, New York, USA). An isotropic model of the maxilla was fabricated according to the finite element method by insertion of mechanical properties of the tooth structures, with orthodontic force (1.5 N) simulation in the distal movement on the upper canine of a hemiarch. RESULTS: Initial movement was larger when micro-osteoperforations were performed on the dental crown (24%) and on the periodontal ligament (29%). In addition, stress distribution was higher on the bone structure (31%) when micro-osteoperforations were used. CONCLUSIONS: Micro-osteoperforations considerably increased the movement of both the dental crown and periodontal ligament, which highlights their importance in the improvement of orthodontic movement, as well as in stress distribution across the bone structure. Important stress absorption regions were identified within micro-osteoperforations.
Assuntos
Análise de Elementos Finitos , Ligamento Periodontal , Técnicas de Movimentação Dentária , Técnicas de Movimentação Dentária/métodos , Humanos , Ligamento Periodontal/fisiologia , Maxila/fisiologia , Estresse Mecânico , Tomografia Computadorizada de Feixe Cônico/métodos , Fenômenos BiomecânicosRESUMO
BACKGROUND: Cranial, facial, nasal, and maxillary widths have been shown to be significantly affected by the individual's sex. The present study aims to use measurements of dental arch and maxillary skeletal base to determine sex, employing supervised machine learning. MATERIALS AND METHODS: Maxillary and mandibular tomographic examinations from 100 patients were analyzed to investigate the inter-premolar width, inter-molar width, maxillary width, inter-pterygoid width, nasal cavity width, nostril width, and maxillary length, obtained through Cone Beam Computed Tomography scans. The following machine learning algorithms were used to build the predictive models: Logistic Regression, Gradient Boosting Classifier, K-Nearest Neighbors (KNN), Support Vector Machine (SVM), Multi-Layer Perceptron Classifier (MLP), Decision Tree, and Random Forest Classifier. A 10-fold cross-validation approach was adopted to validate each model. Metrics such as area under the curve (AUC), accuracy, recall, precision, and F1 Score were calculated for each model, and Receiver Operating Characteristic (ROC) curves were constructed. RESULTS: Univariate analysis showed statistical significance (p < 0.10) for all skeletal and dental variables. Nostril width showed greater importance in two models, while Inter-molar width stood out among dental measurements. The models achieved accuracy values ranging from 0.75 to 0.85 on the test data. Logistic Regression, Random Forest, Decision Tree, and SVM models had the highest AUC values, with SVM showing the smallest disparity between cross-validation and test data for accuracy metrics. CONCLUSION: Transverse dental arch and maxillary skeletal base measurements exhibited strong predictive capability, achieving high accuracy with machine learning methods. Among the evaluated models, the SVM algorithm exhibited the best performance. This indicates potential usefulness in forensic sex determination.
Assuntos
Tomografia Computadorizada de Feixe Cônico , Arco Dental , Aprendizado de Máquina , Maxila , Humanos , Feminino , Masculino , Maxila/diagnóstico por imagem , Maxila/anatomia & histologia , Tomografia Computadorizada de Feixe Cônico/métodos , Adulto , Arco Dental/diagnóstico por imagem , Arco Dental/anatomia & histologia , Pessoa de Meia-Idade , Adulto Jovem , Determinação do Sexo pelo Esqueleto/métodos , Adolescente , Análise para Determinação do Sexo/métodos , Estudos RetrospectivosRESUMO
OBJECTIVES: To document the case of a patient who underwent several endodontic treatments due to a glandular odontogenic cyst misdiagnosed as an inflammatory periapical lesion. BACKGROUND: Glandular odontogenic cysts behave more aggressively, while others have an indolent course. There is limited information on this cyst in the gerodontologic literature. MATERIALS AND METHODS: A 76-year-old male patient presented with an asymptomatic expansive lesion in the anterior mandible resistant to several endodontic treatments. Cone-beam computed tomography revealed a multilocular osteolytic lesion measuring 6.0 × 4.0 cm, with cortical bone perforation. RESULTS: Histopathological analysis of a biopsy specimen was consistent with glandular odontogenic cyst. The patient underwent marginal mandibulectomy with preservation of the base of the mandible. CONCLUSION: A strict diagnostic process is important to avoid unwanted consequences, particularly in the geriatric population.
Assuntos
Tomografia Computadorizada de Feixe Cônico , Erros de Diagnóstico , Cistos Odontogênicos , Humanos , Idoso , Masculino , Cistos Odontogênicos/diagnóstico , Cistos Odontogênicos/patologia , Cistos Odontogênicos/cirurgia , Doenças Mandibulares/diagnóstico , Doenças Mandibulares/cirurgia , Doenças Mandibulares/diagnóstico por imagem , Doenças Mandibulares/patologia , Doenças Periapicais/diagnóstico , Doenças Periapicais/diagnóstico por imagem , Doenças Periapicais/patologiaRESUMO
El foramen mental, una abertura en la parte inferior de la mandíbula, es la salida de un ramo del nervio alveolar inferior, proporcionando sensibilidad a la mandíbula y la piel del mentón. Su variabilidad anatómica es importante en procedimientos dentales y quirúrgicos. Nuestro estudio en San Luis Potosí, México, examinó la posición y características morfológicas del foramen mental en una muestra de tomografías computarizadas de la mandíbula. En mujeres, la zona entre el primer y segundo premolar fue la más común, mientras que en hombres, fue la misma zona pero con mayor prevalencia en el lado izquierdo. Se observaron diferencias en la dirección del foramen mental entre sexos y lados de la mandíbula, con la dirección posterior predominante en ambos sexos. Estos hallazgos concuerdan con estudios previos en diferentes poblaciones, aunque se identifican variaciones significativas en la prevalencia y ubicación específica del foramen. La comparación con otros estudios resalta la importancia de considerar factores étnicos y geográficos en la interpretación de los resultados. Las diferencias anatómicas observadas tienen implicaciones clínicas importantes para procedimientos dentales y quirúrgicos, subrayando la necesidad de enfoques adaptados a la población específica para mejorar la precisión y seguridad de las intervenciones en el área del mentón.
SUMMARY: The mental foramen, an opening at the bottom of the jaw, is the exit of the inferior alveolar nerve branch, providing sensation to the jawbone and skin of the chin. Its anatomical variability is important in dental and surgical procedures. Our study was carried out in San Luis Potosí, Mexico and examined the position and morphological characteristics of the mental foramen in a sample of lower jaw CT scans. In women, the area between the first and second premolar was the most common, while in men, it was the same area but with a greater prevalence on the left side. Differences in the direction of the mental foramen were observed between sexes and sides of the mandible, with the posterior direction predominating in both sexes. These findings are consistent with previous studies in different populations, although significant variations in the prevalence and specific location of the foramen are identified. The comparison with other studies highlights the importance of considering ethnic and geographic factors in the interpretation of results. The anatomical differences observed have important clinical implications for dental and surgical procedures, underscoring the need for approaches tailored to the specific population to improve precision and safety of interventions in the mental foramen area.
Assuntos
Humanos , Masculino , Feminino , Tomografia Computadorizada de Feixe Cônico , Forame Mentual/diagnóstico por imagem , Estudos Transversais , Estudos Retrospectivos , Mandíbula/diagnóstico por imagemRESUMO
OBJECTIVES: To evaluate the influence of multiplanar reconstruction thickness on the detection of peri-implant bone defects with a standalone zirconia implant and compare it to when another implant is in the vicinity using cone-beam computed tomography (CBCT). MATERIALS AND METHODS: Five dry human mandibles were used to create twenty implant sites in the second premolar and first molar regions. The OP300 Maxio was used to acquire CBCT images (90 kVp, 6.3 mA, 5 × 5 cm FOV, and 0.125 mm3 voxel size) before and after creating 3 mm peri-implant bone defects in the buccal aspect of the premolar region. Half of the scans featured a single zirconia implant in the premolar region, while the others had two implants in the premolar and molar regions. Three reconstruction thicknesses (0.125 mm, 1 mm, and 2 mm) were considered for the multiplanar reconstruction analyses. Five oral and maxillofacial radiologists assessed the detection of peri-implant bone defects using a 5-point scale. Diagnostic parameters were calculated and compared using Two-way ANOVA (α = .05). RESULTS: The studied factors showed no significant influence on the diagnosis of peri-implant bone defects (p > .05). Diagnostic performance was notably higher with a single implant, especially with a 2-mm reconstruction thickness (AUC = 0.88, sensitivity = 0.68, specificity = 0.94). Although the differences were not statistically significant, the results were more modest when two implants were present (AUC = 0.80, sensitivity = 0.58, specificity = 0.82). CONCLUSIONS: The presence of an adjacent zirconia implant and variations in reconstruction thickness did not influence the detection of 3 mm buccal peri-implant bone defects on CBCT images.
Assuntos
Tomografia Computadorizada de Feixe Cônico , Implantes Dentários , Mandíbula , Zircônio , Humanos , Tomografia Computadorizada de Feixe Cônico/métodos , Mandíbula/diagnóstico por imagem , Mandíbula/cirurgia , Perda do Osso Alveolar/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodosRESUMO
OBJECTIVES: To investigate long-term alveolar ridge bone changes in patients treated with the split-crest technique (SCT) with simultaneous implant placement. MATERIALS AND METHODS: Alveolar ridge width (ARW) was measured with a caliper immediately before (ARW1) and after SCT (ARW2) with a caliper. Existing CBCT scans taken at least 5 years postoperatively were used to assess the healed ARW (ARWF), buccal bone thickness (BBT), and lingual/palatal bone thickness (L/PBT) at 0, 3, and 5 mm apically from implant platform level (IPL). The distance between IPL and buccal bone crest (IPL-BBC) was also measured. Findings were compared with Wilcoxon and Student's t tests (p < .05). RESULTS: Records of thirty patients with 85 implants were included. Eleven patients (31 implants) presented CBCT scans taken in two separate occasions, resulting in 116 measurements. Tomographic follow-up ranged from 5 to 18 years (11.5 ± 4.18 years). Mean ARW increased from 3.2 ± 0.6 to 6.6 ± 0.48 mm after SCT, but significantly reduced overtime to 4.46 ± 0.83 mm (ARWF) (p < .0001). Mean BBT was 0.5 ± 0.9, 1.3 ± 0.9, and 2.0 ± 1.2 mm, while mean L/PBT was 0.9 ± 0.7, 1.6 ± 0.9, and 2.1 ± 1.0 mm at 0, 3, and 5 mm from IPL, respectively. IPL-BBC distance varied up to 8.7 mm (1.4 ± 2.0 mm), with 56/116 measurements (51/85 implants) showing IPL-BBC = 0 mm. CONCLUSION: Although SCT with simultaneous implant placement can predictably increase ARW postoperatively, ARW tended to significantly reduce over time, due to reductions in BBT and L/PBT, especially coronally. Nonetheless, 60% of the implants still presented some buccal bone at IPL.