RESUMO
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
Batoids (rays and skates) are cartilaginous fishes whose jaws are not articulated directly to the neurocranium. The only point of contact between them are the hyomandibular cartilages, resulting in a unique mandibular suspension called euhyostyly. Due to this decoupling of the jaws from the skull, muscles play an essential role in modulating mandibular movements during the feeding process, especially during mandibular protrusion. The main objectives of our study were: (1) to examine the mandibular musculature of eight batoid species from different orders in the Batoidea and (2) establish a standardized musclulature terminology for future comparative myological studies in batoids. For each muscle bundle, the general characteristics of each cranial muscle were described and their origin and insertions were identified. The number of muscle bundles differed intraspecifically. On the dorsal surface, we reported the first evidence of the presence of the precranial muscle (PCM) in U. halleri, as well as the ethmoideo-parethmoidalis muscle (ETM) in R. velezi, P. glaugostigma and Z. exasperata; in addition, the insertion of the spiracularis muscle (SP) extended to the ventral surface of the oropharyngeal tract in myliobatiforms. On the ventral surface of the head, both N. entemedor and M. californica exhibited additional muscles in the mandibular area. These muscles were renamed as part of the standardization of mandibular terminology: the depressor mandibularis minor (DMM) in N. entemedor and the adductor mandibulae profundus (AMP) in M. californica. The standardization of terminology is essential for futures studies of the mandibular apparatus in batoids, to facilitate the morphological description of muscles in species without anatomical accounts and for continuity in broader comparative analyses.
Assuntos
Terminologia como Assunto , Animais , Crânio/anatomia & histologia , Mandíbula/anatomia & histologia , Músculo Esquelético/anatomia & histologiaRESUMO
OBJECTIVE: This systematic review aimed to verify if individuals with thalassemia present changes in radiomorphometric indices and fractal analysis that can be accessed using panoramic radiographs. MATERIAL AND METHODS: Observational studies that evaluated cortical and trabecular bone patterns in dental routine radiographs were selected from six bibliographic databases. Risk of bias was analyzed using the Joanna Briggs Institute Critical Appraisal Checklists. Quality of evidence was verified using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach. RESULTS: Two hundred three studies were initially retrieved from databases. Three cross-sectional studies, encompassing a total of 129 thalassemic patients, were deemed eligible after applying the inclusion criteria. Bone mineral density (BMD) evaluations were performed using panoramic radiographs and considered the following radiomorphometric indexes: mandibular cortical index (MCI), mandibular cortical width (MCW), panoramic mandibular index (PMI). Fractal dimension analysis (FDA) and simple visual estimation (SVE) were also employed. Overall, FDA and MCW from thalassemia individuals were lower than controls. CONCLUSION: FDA and MCW are frequently altered in patients with thalassemia and may be employed as screening tools for reduced BMD. However, the certainty of evidence for this outcome was very low, mainly due to methodological flaws.
Assuntos
Densidade Óssea , Mandíbula , Radiografia Panorâmica , Talassemia , Humanos , Talassemia/diagnóstico por imagem , Mandíbula/diagnóstico por imagemRESUMO
INTRODUCTION: The early diagnosis of mandibular asymmetry (MA) in patients with unilateral cleft lip and palate (UCLP) can contribute to its treatment. OBJECTIVE: The aim of this study was to evaluate the occurrence and the extent of MA in UCLP patients at different growth stages. METHODS: Cone-beam computed tomography (CBCT) of 47 UCLP patients were included, and divided into two groups (prepubertal stage and pubertal stage). The mandibular ramus height (Co-Go), mandibular body length (Go-Me), total mandibular length (Co-Me), gonial angle (CoGoMe), the volume of the mandibular condyles, and lateral chin deviation were evaluated. The cleft side (CS) and noncleft side (NCS) were compared using the paired t-test for dependent samples. Chin deviation and its possible association with specific sides were evaluated using the Mann-Whitney and Fisher's Exact tests, respectively. The significance level was set at 5%. RESULTS: Comparison of CS and NCS revealed that in prepubertal stage, Co-Me was shorter (105.5 ± 5.7 mm; p = 0.036) in the CS, and that in pubertal stage, Co-Go was lower (46 ± 6 mm; p= 0.004) and Go-Me was greater (78.5 ± 5.8 mm; p = 0.026) in the CS. In both growth stages, a significant association (p< 0.05) was observed between the side to which the chin has deviated and the CS. CONCLUSIONS: Although patients with UCLP in the prepubertal and pubertal stages presented significant measurements revealing MA, only Co-Go in the pubertal stage showed a clinically relevant difference. This specific result indicates that MA must be monitored during patients' growth.
Assuntos
Fenda Labial , Fissura Palatina , Tomografia Computadorizada de Feixe Cônico , Assimetria Facial , Imageamento Tridimensional , Mandíbula , Humanos , Fenda Labial/diagnóstico por imagem , Fenda Labial/fisiopatologia , Fissura Palatina/diagnóstico por imagem , Fissura Palatina/fisiopatologia , Estudos Transversais , Criança , Feminino , Masculino , Mandíbula/crescimento & desenvolvimento , Mandíbula/diagnóstico por imagem , Adolescente , Assimetria Facial/diagnóstico por imagem , Imageamento Tridimensional/métodos , Puberdade/fisiologia , Queixo/diagnóstico por imagem , Queixo/crescimento & desenvolvimento , CefalometriaRESUMO
OBJECTIVE: This retrospective study aimed to compare the three-dimensional (3D) outcomes of the novel miniscrew-anchored maxillary protraction (MAMP) therapy and the bone-anchored maxillary protraction (BAMP) therapy. METHODS: The sample comprised growing patients with skeletal Class III malocclusion treated with two skeletal anchored maxillary protraction protocols. The MAMP group comprised 22 patients (9 female, 13 male; 10.9â ±â 0.9 years of age at baseline) treated with Class III elastics anchored on a hybrid hyrax expander in the maxilla and two mandibular miniscrews distally to the permanent canines. The BAMP group comprised 24 patients (14 female, 10 male; 11.6â ±â 1.1 years of age at baseline) treated with Class III elastic anchored in two titanium miniplates in the infra-zygomatic crest and two miniplates in the mesial of the mandibular permanent canines. Three-dimensional displacements were measured in the pre- and post-treatment cone-beam computed tomography scans superimposed on the cranial base using the Slicer Automated Dental Tools module of 3D Slicer software (www.slicer.org). Mean differences (MD) between groups and 95% confidence interval (CI) were obtained for all variables. Intergroup comparison was performed using the Analysis of Covariance (Pâ <â .05). RESULTS: Both groups showed improvements after treatment. The MAMP group showed a smaller anterior (MD: -1.09 mm; 95% CI, -2.07 to -0.56) and 3D (MD: -1.27 mm; 95% CI, -2.16 to -0.74) displacements of the maxilla after treatment when compared with BAMP. Both groups showed negligible and similar anteroposterior changes in the mandible (MD: 0.33 mm; 95% CI, -2.15 to 1.34). A greater increase in the nasal cavity width (MD of 2.36; 95% CI, 1.97-3.05) was observed in the MAMP group when compared with BAMP. LIMITATIONS: The absence of an untreated control group to assess the possible growth impact in these findings is a limitation of this study. CONCLUSION: Both BAMP and MAMP therapies showed adequate 3D outcomes after treatment. However, BAMP therapy produced a greater maxillary advancement with treatment, while MAMP therapy showed greater transversal increases in the nasal cavity.
Assuntos
Placas Ósseas , Parafusos Ósseos , Tomografia Computadorizada de Feixe Cônico , Imageamento Tridimensional , Má Oclusão Classe III de Angle , Maxila , Procedimentos de Ancoragem Ortodôntica , Técnica de Expansão Palatina , Humanos , Feminino , Masculino , Procedimentos de Ancoragem Ortodôntica/instrumentação , Procedimentos de Ancoragem Ortodôntica/métodos , Estudos Retrospectivos , Má Oclusão Classe III de Angle/terapia , Má Oclusão Classe III de Angle/diagnóstico por imagem , Técnica de Expansão Palatina/instrumentação , Tomografia Computadorizada de Feixe Cônico/métodos , Criança , Imageamento Tridimensional/métodos , Maxila/diagnóstico por imagem , Cefalometria/métodos , Desenho de Aparelho Ortodôntico , Resultado do Tratamento , Dente Canino/diagnóstico por imagem , Mandíbula/diagnóstico por imagemRESUMO
The objective of this study was to evaluate the fractal dimension (FD) and lacunarity of the mandibular bone, comparing patients with and without osteoradionecrosis (ORN). In a cross-sectional study with a control group, 25 patients were included and divided into a case group (with ORN, n = 14) and a control group (without ORN, n = 11). A digital panoramic radiograph taken after the end of radiotherapy (RT) was evaluated for each patient. FD and lacunarity of the mandibular bone were determined using ImageJ software. Descriptive, bivariate, and ROC curve analyses were performed. Cohen's d effect sizes were calculated. Significance was established at p < 0.05. The mean FD and lacunarity values were not significantly different between the groups. The area under the curve for FD and lacunarity were 0.579 and 0.661, respectively. The cut-off point for FD was ≤1.1714 and for lacunarity, > 0.3821, correctly classifying the majority of cases and controls. Most participants in the case group (63.6%) had a FD ≤ 1.1714 and the majority of participants in the control group (63.6%) had a FD >1.1714 (p = 0.395). For lacunarity, most individuals in the case group (72.7%) had a value > 0.3821 and most participants in the control group (63.6%) had a value ≤ 0.3821 (p = 0.198). In conclusion, the FD and lacunarity values did not show statistically significant differences between patients with and without ORN. However, the moderate and large magnitude of the effects seem to indicate that the results may be clinically relevant.
Assuntos
Fractais , Mandíbula , Doenças Mandibulares , Osteorradionecrose , Radiografia Panorâmica , Humanos , Osteorradionecrose/diagnóstico por imagem , Estudos Transversais , Masculino , Feminino , Pessoa de Meia-Idade , Estudos de Casos e Controles , Doenças Mandibulares/diagnóstico por imagem , Idoso , Mandíbula/efeitos da radiação , Mandíbula/diagnóstico por imagem , Valores de Referência , Adulto , Curva ROC , Estatísticas não Paramétricas , Reprodutibilidade dos TestesRESUMO
INTRODUCTION: The Marginal Mandibular Nerve (MMN), despite being didactically described as being a unique branch of the other branches of the Facial Nerve, has in practice an abundant anatomical variation. Both in relation to its ramifications and the positioning of these in relation to the lower edge of the mandible, as well as its anastomoses along its path, play a fundamental role in the surgical strategy during the approach of this cervicofacial site, and can generate, as underestimated its characteristics, inadvertent injuries and motor consequences to the patient. OBJECTIVE: To analyze the types of anatomical variations of the MMN in relation to its position, ramification, and distance from reference points, as well as its incidence that could imply technical difficulties in surgery. METHODS: A systematic review was conducted in the literature in search of anatomical studies, in vivo or in cadavers, between 1981 and 2024, which described the quantification of the MMN branches, their positioning and peculiarities in relation to anastomoses with other peripheral nerves. RESULTS: 511 hemifaces were studied, with the identification of 290 cases of single nerve, 160 cases of double branch, 54 cases of triple branch, and 7 cases of quadruple branch. Of the 456 nerves that were possible to study, the average distance when superior to the lower limit of the mandible was 1.61 cm, while its lower analysis was 2.53 cm. The branches presented different proportions of presentation in relation to this reference point depending on how many branches it had, being more common to remain below it. Anastomoses were identified between the MMN and the buccal and cervical branch of the Facial Nerve, as well as with the Trigeminal Nerve. CONCLUSION: The varied presentations of the MMN, both in its anatomical positioning and in the number of branches leads us to question whether the surgical thinking when performing an exploration in this site may not be the reason whythe authors verify several motor complaints superior to described injuries.
Assuntos
Variação Anatômica , Mandíbula , Nervo Mandibular , Humanos , Nervo Mandibular/anatomia & histologia , Mandíbula/anatomia & histologia , Mandíbula/inervação , CadáverRESUMO
OBJECTIVES: This study aimed to investigate cracked teeth and vertical root fracture observable on micro-CT images of extracted roots of mandibular incisors, after fiber post removal. MATERIALS AND METHODS: Thirty mandibular incisors were selected with any degree of slight incisal wear inspected with the aid of a stereomicroscope under 12x magnification, in order to have a group of young adult specimens according to the criteria of Hugoson et al. A sample of twelve mandibular incisors were selected, aged between 20 and 30 years old, with similar dentine volume and thickness. The specimens were scanned in a micro-computed tomography (micro-CT) device and submitted to root canal shaping, root canal filling, post space preparation, post placement and post removal. RESULTS: From a total of six experimental endodontic timepoints until post removal of 12 mandibular incisors, 64,800 cross-sectional images were analyzed and no vertical root fracture (VRF) or cracked tooth were detected. CONCLUSIONS: Micro-CT assessment after ex vivo fiber post removal did not detect vertical root fracture or cracked tooth formation in the root canal walls of mandibular incisors. CLINICAL RELEVANCE: This study highlighted that fiber post removal per se was not able to propagate VRF or cracked tooth formation or promoted any interruption of the integrity of human root dentin.
Assuntos
Incisivo , Técnica para Retentor Intrarradicular , Fraturas dos Dentes , Microtomografia por Raio-X , Humanos , Incisivo/lesões , Incisivo/diagnóstico por imagem , Fraturas dos Dentes/diagnóstico por imagem , Adulto , Raiz Dentária/diagnóstico por imagem , Raiz Dentária/lesões , Técnicas In Vitro , Mandíbula/diagnóstico por imagem , Dentina/diagnóstico por imagem , Dentina/lesões , Adulto Jovem , Síndrome de Dente Quebrado/diagnóstico por imagemRESUMO
Characteristics of the mandible structures have been relevant in anthropological and forensic studies for sex prediction. This study aims to evaluate the coronoid process, condyle, and sigmoid notch patterns in sex prediction through supervised machine learning algorithms. Cephalometric radiographs from 410 dental records of patients were screened to investigate the morphology of the coronoid process, condyle, and sigmoid notch and the Co-Gn distance. The following machine learning algorithms were used to build the predictive models: Decision Tree, Gradient Boosting Classifier, K-Nearest Neighbors (KNN), Logistic Regression, Multilayer Perceptron Classifier, Random Forest Classifier, and Support Vector Machine (SVM). A 5-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 ROC curves were constructed. All tested variables demonstrated statistical significance (p < 0.10) and were included in the construction of the predictive model. The Co-Gn variable stood out as the most important among the evaluated independent variables, showing greater relevance in three of the four algorithms used in assessing feature importance. In the analysis of the models' performance, the AUC ranged from 0.82 [95% CI = 0.72-0.93] to 0.66 [95% CI = 0.53-0.76] for the test data, and from 0.83 [95% CI = 0.80-0.87] to 0.71 [95% CI = 0.61-0.75] for cross-validation. The precision of the models ranged from 0.83 [95% CI = 0.75-0.91] to 0.68 [95% CI = 0.58-0.78] in the test phase, and from 0.78 [95% CI = 0.74-0.82] to 0.69 [95% CI = 0.65-0.75] in cross-validation. The SVM, KNN, and Gradient Boosting Classifier algorithms stood out with the highest AUC and precision values in both cross-validation and testing. The use of condyle, coronoid process, and sigmoid notch characteristics, in combination with supervised machine learning predictive models, shows potential for contributing to sex prediction based on morphometric bone characteristics, particularly regarding the distance between the condyle and gnathion. However, given the study's limitations, these findings should be interpreted with caution.
Assuntos
Aprendizado de Máquina , Humanos , Masculino , Feminino , Adulto , Côndilo Mandibular/diagnóstico por imagem , Algoritmos , Adulto Jovem , Adolescente , Determinação do Sexo pelo Esqueleto/métodos , Máquina de Vetores de Suporte , Pessoa de Meia-Idade , Cefalometria/métodos , Mandíbula/diagnóstico por imagem , Mandíbula/anatomia & histologia , Curva ROCRESUMO
OBJECTIVES: To investigate the influence of combining levels of metal artifact reduction (MAR) tool with different filters and slice-thickness in the detection of mandibular canals perforated by implants on CBCT scans and to objectively assess the impact of the aforementioned combinations. MATERIALS AND METHODS: Implants were placed above (8 implants) and inside (10 implants) mandibular canals of dried-mandibles. CBCT scans were obtained with the Eagle 3D unit (85 kVp, 8 mA, 5 × 5 cm FOV, 130 µm voxel size, and off/medium/high MAR levels). Examiners evaluated the scans under each MAR level and across different conditions: no filter, Sharpen 1×, Sharpen 2×; 0 mm, 1 mm, and 2 mm slice-thickness. The gray values on axial reconstructions were assessed. Area under the receiver operating characteristic curve (AUC), sensitivity, specificity, mean and standard deviation (SD) for gray values were calculated and compared by multi-way Analysis of Variance. RESULTS: Overall, the AUC and sensitivity decreased with high-level MAR (p < 0.0001), regardless other variables tested. Enabling MAR tool decreased mean gray values (p < 0.01) and increasing MAR levels reduced the SD values on scans with Sharpen 2× (p < 0.012). CONCLUSIONS: High-level MAR impairs the visualization of mandibular canals perforated by implants. Moreover, enabling MAR tool decreases the mean gray values. CLINICAL RELEVANCE: MAR tool, filters, and slice thickness influence the image quality of CBCT scans. Therefore, it is important to evaluate the impact of these parameters on the diagnosis of mandibular canals perforated by implants.
Assuntos
Artefatos , Tomografia Computadorizada de Feixe Cônico , Implantes Dentários , Mandíbula , Metais , Tomografia Computadorizada de Feixe Cônico/métodos , Humanos , Mandíbula/diagnóstico por imagem , Mandíbula/cirurgia , Sensibilidade e Especificidade , Técnicas In Vitro , Imageamento Tridimensional/métodosRESUMO
BACKGROUND: The surgical treatment for mandibular repositioning using a bilateral sagittal split osteotomy (BSSO) favours the development of techniques that result in adequate repair and stability. In Puricelli's mandibular sagittal split osteotomy (PMSSO) proposal, the vertical lateral cut osteotomy is located in the interradicular space between the lower first molar and second premolar. OBJECTIVES: This in silico study aimed to investigate the mechanical stability of PMSSO and compare it with the classical Obwegeser-Dal Pont technique for mandibular advancement. MATERIALS AND METHODS: A computational geometric model of the mandible was created in a virtual environment using computer-aided design (CAD) software. After reproducing the advancements, two test groups were developed: GTOD10, Obwegeser-Dal Pont osteotomy, and GTP10, Puricelli osteotomy, both simulating a 10-mm mandibular advancement, allowing for measuring the area of overlap between bone segments. With the geometric changes promoted by the osteotomy, boundary conditions of displacement and force were applied to a CAD software based on finite element analysis (FEA), allowing for quantitative and comparative analysis of the stress and vertical displacement of the mandible, mechanical measurements that may be associated with strength and stiffness. RESULTS: A 17.48% higher stress was observed in the GTP10 group than in GTOD10. However, the region of highest stress in GTP10 was found in a part of the bone that was still intact and far from the area of fragility caused by lateral vertical osteotomy. In contrast, in GTOD10, the region with high stress was in a less resistant bone region. The GTP10 group showed a 28.73% lower displacement than GTOD10. The area of overlap between the proximal and distal segments of the mandible was 33.13% larger in the GTP10 than in the GTOD10 group. CONCLUSION: The PMSSO method, performed in large mandibular advancements, keeps the point of highest stress away from the mandibular fragility zone. Considering the same amount of advancement, it also promotes less displacement and larger areas of bone overlap. CLINICAL RELEVANCE: The results suggest that PMSSO, applied in large mandibular advancement, presents greater postoperative stability.
Assuntos
Análise de Elementos Finitos , Mandíbula , Avanço Mandibular , Osteotomia Sagital do Ramo Mandibular , Humanos , Osteotomia Sagital do Ramo Mandibular/métodos , Fenômenos Biomecânicos , Avanço Mandibular/métodos , Mandíbula/cirurgia , Mandíbula/diagnóstico por imagem , Simulação por Computador , Imageamento Tridimensional , Desenho Assistido por ComputadorRESUMO
Several impression techniques and theories have been developed for implant-retained overdentures, each with its own set of advantages and limitations. This study aimed to assess the chewing efficiency of mandibular implant-retained overdentures fabricated using three distinct impression techniques (mucofunctional, selective, and minimal pressure impression techniques). Twenty-six patients with complete edentulism free from any oral or systemic disease were selected to participate in the study. Three complete mandibular implant-retained overdentures were constructed for each patient, and grouped into three groups according to the impression technique employed in overdenture construction; Group A: Patients were treated by mandibular implant-retained overdenture fabricated using mucofunctional impression technique; Group B: Patients were treated by mandibular implant-retained overdenture fabricated using selective pressure impression technique; Group C: Patients were treated by mandibular implant-retained overdenture fabricated using minimal pressure impression technique. Chewing efficiency was evaluated for each patient with the implant-retained mandibular overdenture after three months of prosthesis insertion as an adaptation period. The data were collected, tabulated, and statistically analyzed. Results indicated that mandibular implant-retained overdentures made using the mucofunctional impression technique showed higher mean values of chewing efficiency parameters than mandibular overdentures made using selective and minimal pressure impression techniques. Within the limitations of this study, it can be concluded that the mucofunctional impression technique may be effective in improving the chewing efficiency of mandibular implant-retained overdentures more than minimal or selective pressure impression techniques.
Assuntos
Técnica de Moldagem Odontológica , Prótese Dentária Fixada por Implante , Revestimento de Dentadura , Mastigação , Humanos , Mastigação/fisiologia , Feminino , Masculino , Pessoa de Meia-Idade , Mandíbula , Idoso , Planejamento de Dentadura , Retenção de Dentadura/métodos , Arcada Edêntula/reabilitaçãoRESUMO
The objective of this study was to compare the aging changes of the dental arches in patients treated without extractions and untreated normal occlusion subjects after a four-decade follow-up. This retrospective study evaluated two groups: The Treated Group (Group T) comprised 16 patients (6 male; 10 female) presenting with Class I or Class II malocclusions treated orthodontically without extractions. Dental models were evaluated 3 stages: T1 (pretreatment, 13.20 years), T2 (posttreatment, 15.07 years) and T3 (long-term posttreatment, 50.32 years). The Untreated Group (Group UT) consisted of 22 untreated normal occlusion individuals. The dental casts were evaluated at the ages of 13.32 (T1), 17.82 (T2) and 60.95 years (T3). The dental casts were digitized and the irregularity index, intercanine, interpremolar and intermolar widths, overjet and overbite, arch length and perimeter were measured. Intergroup comparisons were performed with independent t tests (P < 0.05). From T1 to T2, the treated group showed maxillary and mandibular crowding and overjet decrease and a maxillary interpremolar and intermolar width increase compared to the untreated group. From T2 to T3, a greater maxillary and mandibular crowding increase and a greater arch length decrease were observed in the treated group compared to the normal occlusion subjects. Overbite increased in the treated group and decreased in the untreated group. The maturational changes of treated patients were different from untreated normal occlusion subjects. Relapse might have contributed for the greater changes observed in incisor crowding and arch length observed in orthodontically treated patients. The aging changes of untreated normal occlusions and nonextraction treated patients, after a four-decade follow-up, proved to be different, indicating that relapse of orthodontic treatment played a role in aging changes of treated patients.
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Arco Dental , Humanos , Masculino , Feminino , Seguimentos , Adolescente , Estudos Retrospectivos , Arco Dental/patologia , Pessoa de Meia-Idade , Oclusão Dentária , Má Oclusão/terapia , Má Oclusão/patologia , Má Oclusão Classe II de Angle/terapia , Má Oclusão Classe II de Angle/patologia , Ortodontia Corretiva/métodos , Envelhecimento/fisiologia , Mandíbula/patologia , Maxila/patologia , Modelos DentáriosRESUMO
Here we describe new fossil material of Antillothrix bernensis, a Pleistocene-Holocene primate taxon from Hispaniola. It is now represented by seven crania, five mandibles, and dozens of postcranial elements from several paleontologically rich cave systems. The five adult crania included here share a similar overall profile as well as specific features such as a deep depression at the glabella. The complete anterior dentition of Antillothrix can now be described for the first time; short canine crowns, in the apicobasal dimension, compare well with titi monkeys, but the new crania and mandibles lack the specialized tall-crowned incisors of the extant pitheciids. They do, however, have a diastema between the lateral maxillary incisors and canines, a feature not present in the previously known crania. The new mandibles deepen posteriorly and have a medial inflection of the mandibular ramus, as in some pitheciids, but also share with Xenothrix a significant vertical narrowing of the corpus under P4/M1 not observed among extant taxa. Two of the specimens, a cranium and a mandible that do not fit together, exhibit congenitally absent third molars-a rarity among extant, noncallitrichine taxa. There is an approximately 1-kg range in the estimated body mass among the full Antillothrix sample (from 2.4 to 3.4 kg), as well as a range of approximately 5 cm3 of endocranial volume (from 40 to 45 cm3). With these extended ranges from the new specimens, Antillothrix can no longer be described as a taxon with a brain size smaller than that expected for its body size. Neither of these ranges in the brain size or body size is large enough to indicate a substantial level of sexual dimorphism or to necessitate separating the sample into male and female individuals. Given this, and the similar canine sizes for all specimens where they are present, the sample is consistent with a morphologically variable but monomorphic species.
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Fósseis , Mandíbula , Crânio , Animais , Fósseis/anatomia & histologia , Crânio/anatomia & histologia , Mandíbula/anatomia & histologia , Feminino , Masculino , Índias OcidentaisRESUMO
Given the high prevalence of skeletal and mandibular diseases in the Patagonian Huemul, comprehensive anatomical studies are essential to understand the impact of nutritional deficiencies and support conservation efforts. The aim of this study is to provide a detailed anatomical characterisation of three exhumed mandibles of Patagonian huemul (Hippocamelus bisulcus) through three-dimensional reconstructions obtained from computed tomography data and semi-automatic segmentation, documenting their distinctive features. The findings revealed distinctive features in the mandible, consistent with the browsing habits of herbivores, such as a robust coronoid process, a wide and deep pterygoid fossa, a significantly lower mandibular condyle compared to other deer species and a unique configuration of the mandibular canal with a curved caudal portion and a straight rostral portion. These anatomical adaptations are likely related to the species' feeding habits and behaviour. The study also addressed the challenges of researching an endangered species, given that access to biological material is restricted by strict regulations in Chile and Argentina. These restrictions limited the available sample size and hindered the acquisition of additional specimens, which could affect the generalisation of the results. Despite these limitations, the research provides valuable anatomical insights that are fundamental for the biology, clinical practice and management of specimens. In conclusion, the mandibles of both juvenile and adult Patagonian huemul demonstrate distinctive features characteristic of browsing herbivores. The findings can serve as a basis for future comparative studies on mandibular anatomy and function in this endangered deer species as well as in other herbivorous deer.
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Cervos , Mandíbula , Tomografia Computadorizada por Raios X , Animais , Mandíbula/anatomia & histologia , Mandíbula/diagnóstico por imagem , Cervos/anatomia & histologia , Cervos/fisiologia , Argentina , Tomografia Computadorizada por Raios X/veterinária , Chile , Masculino , Imageamento Tridimensional/veterinária , FemininoRESUMO
INTRODUCTION: Symmetry is balance, some correspondence in the size, form, and arrangements of parts on opposite sides of a plane, line, or point. The opposite of this concept is asymmetry, or imbalance. OBJECTIVE: This retrospective study compared two methods for assessing arch symmetry with linear measurements based on triangles, to determine their applicability and efficiency. METHODS: Two groups were enrolled: children (n=20) and adults (n=20), and the arch symmetry was assessed from linear measurements. Method 1: the incisor-canine (INC), canine-molar (CM), and incisor-molar (INM) distances (paired t-test and Pearson correlation). Method 2: a mathematical equation between the cusps measurements of the canines and the distobuccal of the first molars leading to result 1 (t-test for one sample and bootstrapping analysis). Dental casts were digitized and analyzed using a software program. The Bland-Altman test compared the methods (α=0.05). RESULTS: The Bland-Altman test revealed concordance between the methods; however, separately the results were different: In method 1, the mandibular arch did not demonstrate correlation (children, INC r=0.33; CM r=0.45; INM r=0.51; adults, CM r=0.46; INM r=0.35), however, the maxilla revealed a strong correlation in children and a strong/moderate correlation in adults. In method 2, both arches were symmetrical (p>0.05). CONCLUSION: Method 1 may be appropriate during orthodontic treatment, and method 2 may be indicated for final treatment. These methods are useful; however, only method 1 identified the side of asymmetry. The methods can contribute to future studies in syndromic and non-syndromic patients, before and after orthognathic surgeries and orthodontic treatment, comparing results.
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Dente Canino , Arco Dental , Incisivo , Dente Molar , Humanos , Arco Dental/anatomia & histologia , Estudos Retrospectivos , Criança , Adulto , Dente Canino/anatomia & histologia , Dente Canino/diagnóstico por imagem , Feminino , Dente Molar/anatomia & histologia , Incisivo/anatomia & histologia , Masculino , Modelos Dentários , Mandíbula/anatomia & histologia , Maxila/anatomia & histologia , Cefalometria/métodos , Adolescente , Adulto JovemRESUMO
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.
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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
BACKGROUND: To verify the influence of macrogeometry with healing chambers on the osseointegration of dental implants by analyzing implant stability quotient (ISQ) and evaluate the correlation between insertion torque and ISQ insertion with different macrogeometries. METHODS: In total, 26 implants were installed in the posterior mandible of eight patients with sufficient bone height for the installation of implants measuring 3.5 mm in diameter and 9.0 mm in length. The implants were categorized according to two types of macrogeometry: a test group (GT) with 13 conical implants with healing chambers and a control group (GC) with 13 conical implants with conventional threads. To insert the implants, a bone drilling protocol was used up to a diameter of 3 mm with the last helical bur. The insertion torque of the implants was evaluated, followed by the measurement of ISQ at 0 (T-0), 7 (T-7), 14 (T-14), 21 (T-21), 28 (T-28), and 42 (T-42) days. RESULTS: The mean insertion torque was 43 Ncm in both groups, without a significant difference. Moreover, no significant difference in the ISQ values was found between the groups at different time points (p > 0.05), except at T-7 (GT = 69.87±1.89 and GC = 66.48±4.49; p = 0.01). Although there was no significant difference, ISQ median values were higher in the GT group than GC group at 28 days (GT = 67.98 and GC = 63.46; p = 0.05) and 42 days (GT = 66.12 and GC = 60.33; p = 0.09). No correlation was found between the insertion torque and ISQ insertion (p > 0.05). CONCLUSION: Furthermore, implants with a 3.5 mm diameter macrogeometry, with or without healing chambers, inserted with a drilling protocol up to 3 mm in diameter of the last helical bur, led to a similar secondary stability, with no difference in ISQ values. Although, implants with healing chamber demonstrates ascending values in the graph of ISQ, having a trend of faster osseointegration than implants without healing chambers. Both macrogeometries provide a similar primary stability to implants. TRIAL REGISTRATION: This study was registered retrospectively in ReBec (brazilian registry of clinical trials) under the number RBR-96n5×69, on the date of 19/06/2023.
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Implantação Dentária Endóssea , Implantes Dentários , Mandíbula , Osseointegração , Torque , Humanos , Osseointegração/fisiologia , Implantação Dentária Endóssea/métodos , Masculino , Feminino , Pessoa de Meia-Idade , Mandíbula/cirurgia , Planejamento de Prótese Dentária , Adulto , Cicatrização , Idoso , Retenção em Prótese Dentária , Propriedades de SuperfícieRESUMO
AIM: This is a report of the 5-year results of a two-group parallel randomized clinical trial comparing longitudinal implant stability, and clinical and radiographic peri-implant outcomes of mandibular overdentures retained by one (1-IOD group) or two (2-IOD group) implants. METHODS: All participants received 4.1 mm diameter tissue-level implants (Straumann® Standard Plus - SLActive®, Institut Straumann AG), installed in the mandible midline (1-IOD; n = 23) or the lateral incisor-canine area bilaterally (2-IOD; n = 24), and loaded after 3 weeks. Implant Stability Quotient (ISQ) was measured using a resonance frequency device (Osstell® Mentor, Integration Diagnostics) at implant placement, after three weeks (loading), and at the 6-month, 1-, 3-, and 5-year follow-ups. Marginal bone loss and clinical implant outcomes (plaque, calculus, suppuration and bleeding) were assessed periodically up to 5 years after loading. RESULTS: Only minor changes in marginal bone level were observed after 5 years (mean = 0.37; SD = 0.44 mm), and satisfactory and stable peri-implant parameters were observed throughout the 5-year follow-up. No significant differences between groups were found. Overall, the mean primary implant stability was considered high (> 70) for the two groups (1-IOD = 78.1 ± 4.5; 2-IOD = 78.0 ± 5.8). No noticeable changes were observed between implant insertion and loading. A marked increase was observed from insertion to the 6-month follow-up - the mean difference for the 1-IOD group was + 5.5 ± 5.5 (Effect size = 1.00), while for the 2-IOD group, the mean difference was + 6.0 ± 5.6 (Effect size = 1.08). No relevant changes were observed throughout the follow-up periods up to 5 years. Linear mixed-effect model regression showed no influence of the bone-related variables (p > 0.05) and the number of implants (p = 0.087), and a significant effect of the time variable (p < 0.001). CONCLUSION: Satisfactory peri-implant outcomes and stable secondary stability suggest good clinical performance and successful long-term osseointegration of the implants for single and two-implant mandibular overdentures. Using a single implant to retain a mandibular overdenture does not seem to result in detrimental implant loading over the five years of overdenture use. CLINICAL RELEVANCE: This study corroborates the use of a single implant to retain a mandibular denture.
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Prótese Dentária Fixada por Implante , Retenção de Dentadura , Revestimento de Dentadura , Mandíbula , Humanos , Masculino , Feminino , Mandíbula/cirurgia , Idoso , Pessoa de Meia-Idade , Resultado do Tratamento , Implantação Dentária Endóssea/métodos , Prótese Total Inferior , Perda do Osso Alveolar/diagnóstico por imagem , Análise de Frequência de RessonânciaRESUMO
This study explored the effects of L-PRF on pain, soft tissue healing, periodontal condition, and post-extraction bone repair of mandibular third molars (3Ms). A randomized, prospective, triple-blind, split-mouth clinical trial was conducted with 34 volunteers. Eligible patients were randomly allocated into two treatments: G1 (without L-PRF), G2 (alveoli filled with L-PRF), in which the removal of bilateral 3Ms was performed at the same surgical time. Outcomes were assessed according to a visual analogue scale (pain), soft tissue scoring system (wound healing), periodontal probing of mandibular second molar. Bone repair was determined by volumetric analysis (ITK-SNAP software) and fractal analysis (ImageJ software). An intention-to-treat approach to Statistical analysis was used. L-PRF reduced pain in the 7-day postoperative follow-up (p = 0.019) and not only improved soft tissue healing after 1 month of follow-up (p = 0.021), but also probing depth (distal face) in 3 months postoperatively (p = 0.011). Significant alveolar reduction occurred in 3 months after surgery in both treatments (p < 0.05), however, this was more significant in G1 (p = 0.016). The fractal dimension showed no statistical differences. L-PRF improved postoperative clinical parameters of pain, soft tissue healing, and periodontal condition, suggesting that it has a beneficial effect on preserving the alveolar ridge and accelerating the initial repair process.