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1.
Niger J Clin Pract ; 24(3): 435-442, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33723120

RESUMO

Aims: To investigate the root canal anatomy and the incidence of fused roots in maxillary first molar (MFM) and maxillary second molar (MSM) teeth in the Turkish population and compare them to teeth with separate roots using cone-beam computed tomography (CBCT). Methods: CBCT images of 616 MFMs and 703 MSMs were analyzed from 402 patients for the number of roots and the presence of fusion. The canal configuration of teeth with separate and fused roots was compared. Type of fusion and canal merging positions were determined. A P value of less than 0.05 was considered significant. Results: Five hundred and seventy-one (92.69%) MFMs had three separate roots, one (0.16%) had four roots and the incidence of root fusion was 7.14%. An additional mesiobuccal (MB) canal was present in 79.34% of the teeth with three separate roots. There was no merging of canals in 36 of 44 teeth with fused roots. The prevalence of fusion was higher in the MSMs (23.47%). The incidence of three and four separate roots in MSM teeth was 74.68% and 1.85%, respectively. The prevalence of additional MB canals in teeth with three separate roots was 53.14%. There was no canal merging in 60% of the fused rooted teeth. There were two-merged canals in 31.52% and multiple merged canals in 8.48% of the MSMs. Conclusions: In the Turkish population, the incidence of root fusion in the MFMs and MSMs was 7.14% and 23.47%, respectively, with more canal merging in the MSMs.


Assuntos
Homossexualidade Masculina , Minorias Sexuais e de Gênero , Tomografia Computadorizada de Feixe Cônico , Cavidade Pulpar/diagnóstico por imagem , Humanos , Masculino , Maxila/diagnóstico por imagem , Dente Molar/diagnóstico por imagem , Raiz Dentária/diagnóstico por imagem
2.
Am J Orthod Dentofacial Orthop ; 159(4): 536-544, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33568277

RESUMO

Treatment of an impacted incisor with a dilacerated root is challenging for clinicians because of the position of the impacted incisor, the abnormality of the root, unfavorable prognosis, and, especially, the long treatment duration. We report on 2 young patients who had inversely impacted maxillary central incisors with developing labially dilacerated roots. Both patients were treated by a novel surgical approach, in situ rotation, by which the crowns of the inversely impacted incisors were carefully rotated to a relatively normal position, whereas the apical location remained relatively unchanged. About 2 weeks after surgery, spontaneous eruption of the treated incisors was observed. Three months later, the postoperative central incisors were further aligned into the maxillary arch with a fixed orthodontic appliance. Follow-up visits 2 or 3 years after surgery indicated that the positions of the dilacerated incisors maintained stability with good gingival esthetics, and the pulpal vitality was favorable. The roots grew further in a relatively normal direction of the incisor's longitudinal axis, which was different from the initial curvature angle. Moreover, with the in situ rotation surgery, treatment time was greatly reduced and resulted in a favorable prognosis compared with conventional treatment.


Assuntos
Incisivo , Dente Impactado , Estética Dentária , Humanos , Incisivo/cirurgia , Maxila/diagnóstico por imagem , Maxila/cirurgia , Rotação , Raiz Dentária/diagnóstico por imagem , Raiz Dentária/cirurgia , Dente Impactado/diagnóstico por imagem , Dente Impactado/cirurgia
3.
Braz Oral Res ; 35: e022, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33605353

RESUMO

This study aimed to determine the mean distances between apexes of the maxillary posterior teeth and the maxillary sinus, between apexes of the mandibular posterior teeth and the mandibular canal, and between the root apexes of all teeth and the adjacent cortical plates. A total of 800 cone-beam computed tomography (CBCT) scans (400 maxillary and 400 mandibular) were obtained from patients indicated for several treatments. The proximity between apexes and anatomical structures, and the relationship between apexes and adjacent cortical plates were assessed together with the risk of over-instrumentation. Paired-sample comparisons were performed by using the paired t-test. The means were compared by ANOVA, Kruskal-Wallis and Dwass-Steel-Critchlow-Fligner tests. a) Most of the apexes classified as A (high-risk proximity) were observed in maxillary first and second molars, in mandibular first and second molars, and in second premolars in relation to near anatomical structures. b) A predominance of class A (86.42%) was noticed in the first premolars, between apexes of maxillary teeth and adjacent cortical plates. c) The distance between apexes of mandibular teeth and buccal cortical plates showed a predominance of medium-risk proximity (B) in all the groups, except the first premolars, with the highest risk (82.22%), and the second molars, with low-risk proximity (C) to distal and mesiobuccal apexes (91.77% and 89.62%). CBCT images are important for endodontic diagnosis and treatment, since many teeth have high risk proximity to near anatomical structures and adjacent cortical plates.


Assuntos
Seio Maxilar , Raiz Dentária , Córtex Cerebral , Tomografia Computadorizada de Feixe Cônico , Humanos , Dente Molar/diagnóstico por imagem , Raiz Dentária/diagnóstico por imagem
4.
J Endod ; 47(4): 585-591, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33497731

RESUMO

INTRODUCTION: The aim of this study was to evaluate if the configuration of canal orifices can predict the presence of a second mesiobuccal canal (MB2) in maxillary second molars with fused roots. METHODS: Maxillary second molars with fused roots (N = 150) were scanned in a micro-computed tomographic device (pixel size = 9 µm) and evaluated regarding the root fusion type and the incidence of the MB2 canal. The centers of the canal orifices were connected, and the angles formed by the intersection of these lines as well as their distances were measured and statistically compared (1-way analysis of variance). Specimens were then assigned to 2 groups according to the presence (n = 65) or absence (n = 50) of the MB2 canal and compared regarding the angles and interorifice distances using the Welch t test. A binary logistic regression model estimated the association between the interorifice distance, the fusion type, and the presence of the MB2 canal, whereas receiver operating characteristic curve analysis was performed to evaluate the diagnostic abilities of significant variables. The significance level was set at 5%. RESULTS: The most common fusion types were 1 and 6, and MB2 canal incidence was 47.3%. No statistical difference was observed in the angles or interorifice distances among teeth with different fusion types (P > .05). Distances from the mesiobuccal (MB) to the distobuccal and palatal (P) canal orifices as well as the MB and P angles were significantly higher in the presence of an MB2 canal (P < .05). A binary logistic regression model revealed that MB-distobuccal and MB-P distances were significant in the presence of an MB2 canal (P < .05). Receiver operating characteristic analysis indicated that MB-P distance had acceptable diagnostic accuracy for the prediction of MB2 canal presence. Sensitivity (specificity) calculated from the MB-P distances of 4.0, 4.5, and 5.0 mm were 89.2% (36.5%), 76.9% (58.4%), and 44.4% (71.4%), respectively. CONCLUSIONS: MB-P interorifice distance is a strong predictor of the presence of the MB2 canal in maxillary second molars with fused roots.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Raiz Dentária , Cavidade Pulpar/diagnóstico por imagem , Humanos , Maxila/diagnóstico por imagem , Dente Molar/diagnóstico por imagem , Raiz Dentária/diagnóstico por imagem
6.
Am J Orthod Dentofacial Orthop ; 159(3): 271-280, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33485718

RESUMO

INTRODUCTION: This study was aimed at investigating the reliability and accuracy of cone-beam computed tomography (CBCT) diagnosis of contact between a temporary anchorage device (TAD) and tooth root and assessing any effect produced by metal brackets, imaging software program, and image segmentation or color enhancement tools. METHODS: Eighteen fresh pig mandibles were used. TADs (Vector, 1.4 × 8 mm) were placed at the buccal intermolar alveolar bone on both sides of the mandibles. With soft tissue kept intact, each mandible underwent CBCT scans (voxel size, 400 µm) before and after placing TADs, and after placing metal brackets on involved molars. Alveolar bone specimens containing the TADs were then exposed to microcomputed tomography (microCT) scans (voxel size, 27 µm) after TAD removal. Two independent raters, blinded of image identity, diagnosed TAD-root contact using ImageJ (National Institutes of Health and the Laboratory for Optical and Computational Instrumentation, University of Wisconsin, Madison, Wis) for microCT; Dolphin (Dolphin Imaging and Management Solutions, Chatsworth, Calif) and Anatomage software programs (Anatomage, Santa Clara, Calif) for CBCT images. Intrarater and interrater reliability and diagnostic accuracy were statistically assessed using Cohen kappa and McNemar tests. RESULTS: Intrarater and interrater reliability of TAD-root contact diagnoses were perfect for microCT diagnoses (κ = 1), generally moderate to good (κ >0.5) for CBCT diagnoses except for the use of color enhancement tools (κ <0.25). For diagnostic accuracy, there was generally a low agreement (κ <0.45) between CBCT and microCT (gold standard). The percent accuracy ranged from 68.1% to 79.2% and was not different among raters, bracket presence/absence, or software choices (chi-square tests, P >0.05). Overall, diagnostic sensitivity was above 80%, whereas specificity was below 55%. CONCLUSIONS: Despite good reliability, diagnoses of TAD-root contact using 400 µm voxel size CBCT imaging tend to be inaccurate, with a likelihood of high false-positive diagnoses.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Dente Molar , Animais , Dente Molar/diagnóstico por imagem , Reprodutibilidade dos Testes , Suínos , Raiz Dentária/diagnóstico por imagem , Microtomografia por Raio-X
7.
Angle Orthod ; 90(4): 524-531, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33378490

RESUMO

OBJECTIVE: To determine the effect of alveolar decortication on orthodontically induced root resorption. MATERIALS AND METHODS: A total of 24 male Wistar rats (14 week old) were used. The rats were randomly divided into one of the following three groups: group 1 (control group), orthodontic tooth movement (OTM) for 2 weeks; group 2, OTM for 2 weeks + two alveolar decortications (2AD); group 3, OTM for 2 weeks + four alveolar decortications (4AD). The first molar was moved mesially for 2 weeks. Micro computed tomography was used to analyze root volume. In addition, histological sections were stained with Tartrate Resistant Acid Phosphatase (TRAP) to quantify the osteoclast number. RESULTS: The buccal root volume in OTM + 4AD group was decreased by 8.92% and 6.11% when compared with the OTM-only group and OTM + 2AD group, respectively. Similarly, the other four root volumes in the OTM + 4AD group was decreased by 8.99% and 5.24% when compared with the OTM-only group and OTM + 2AD group, respectively. There was a decrease in buccal root density in the OTM + 4AD group by 4.66% and 3.56% when compared with the OTM-only group and the OTM + 2AD group, respectively. In addition, there was an increase in the number of osteoclasts by 195.73% and 98.74% in OTM + 4AD group in comparison with the OTM and OTM + 2AD group. CONCLUSIONS: The amount of orthodontically induced root resorption was positively correlated with the extent of surgical injury used to accelerate orthodontic tooth movement.


Assuntos
Reabsorção da Raiz , Animais , Masculino , Osteoclastos , Ratos , Ratos Wistar , Reabsorção da Raiz/diagnóstico por imagem , Reabsorção da Raiz/etiologia , Técnicas de Movimentação Dentária/efeitos adversos , Raiz Dentária/diagnóstico por imagem , Microtomografia por Raio-X
8.
Angle Orthod ; 90(6): 811-822, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-33378522

RESUMO

OBJECTIVES: To determine the different impact of moment-to-force ratio (M:F) variation for each tooth and spatial plane and to develop a mathematical model to predict the orthodontic movement for every tooth. MATERIALS AND METHODS: Two full sets of teeth were obtained combining cone-beam computed tomography (CBCT) and optical scans for two patients. Subsequently, a finite element analysis was performed for 510 different force systems for each tooth to evaluate the centers of rotation. RESULTS: The center of CROT locations were analyzed, showing that the M:F effect was related to the spatial plane on which the moment was applied, to the force direction, and to the tooth morphology. The tooth dimensions on each plane were mathematically used to derive their influence on the tooth movement. CONCLUSION: This study established the basis for an orthodontist to determine how the teeth move and their axes of resistance, depending on their morphology alone. The movement is controlled by a parameter (k), which depends on tooth dimensions and force system features. The k for a tooth can be calculated using a CBCT and a specific set of covariates.


Assuntos
Técnicas de Movimentação Dentária , Dente , Tomografia Computadorizada de Feixe Cônico , Análise de Elementos Finitos , Humanos , Fenômenos Mecânicos , Dente/diagnóstico por imagem , Raiz Dentária/diagnóstico por imagem
9.
Braz Dent J ; 31(5): 516-522, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33146336

RESUMO

The purpose of this study was to evaluate the accuracy of Cone-Beam Computed Tomography (CBCT) in measuring radicular dentin thickness focused on intraradicular post placement planning treatment. Ten single-rooted human premolars were selected. The teeth were divided into three segments (cervical, middle and apical). The coronal face of the apical and middle sections was selected for the dentin thickness assessment; which was measured from the external root surface to the root canal wall, on the buccal, lingual, mesial, and distal surfaces of each tooth. In situ anatomical measurement was the reference standard, and the corresponding axial CBCT imaging were evaluated by the i-CAT software. The one-way ANOVA test and the Bonferroni post hoc test were applied to compare the groups (p>0.05). CBCT imaging measurements (p=0.003) overestimated the radicular dentin thickness compared to the reference standard. Descriptive analysis showed that the greatest difference between the reference standard and the tomographic measurement means were 0.20 mm. One-way ANOVA test found the statistical significant difference among group's measurements. Bonferroni correction demonstrated statistically significant difference only related lingual surface for the CBCT imaging measurements. CBCT imaging measurements overestimated the radicular dentin thickness. However, the measurement difference was clinically acceptable.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Raiz Dentária , Dente Pré-Molar/diagnóstico por imagem , Cavidade Pulpar , Dentina/diagnóstico por imagem , Humanos , Tratamento do Canal Radicular , Raiz Dentária/diagnóstico por imagem
10.
Am J Orthod Dentofacial Orthop ; 158(5): e99-e109, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33131571

RESUMO

INTRODUCTION: This research aimed to compare the estimation error of the root axis using 3-dimensional (3D) tooth models at the midtreatment stage between the whole-surface scan (WSS) and lingual-surface scan (LSS) methods. METHODS: The sample consisted of 208 teeth (26 each of central incisors, canines, second premolars, and first molars in the maxillary and mandibular dentition) from 13 patients whose pre- and midtreatment intraoral scan and cone-beam computed tomography (CBCT) were available. The 3D tooth models were constructed by merging the intraoral-scan crowns and the CBCT-scan roots obtained at the pretreatment stage. To estimate the root axis at the midtreatment stage, we superimposed the individual 3D tooth models onto the midtreatment intraoral scan obtained by the WSS and LSS methods. The midtreatment CBCT scan was used as the gold standard to determine the real root axis. The estimated root axis in terms of mesiodistal angulation and buccolingual inclination was measured in the WSS and LSS methods, and statistical analysis was performed. RESULTS: The estimation errors of the mesiodistal angulation and buccolingual inclination were <2.0° in both methods. The LSS method demonstrated a statistically larger but clinically insignificant estimation error than the WSS method in the mandibular canine (mesiodistal angulation, 1.95° vs 1.62°) and the total tested teeth (mesiodistal angulation, 1.40° vs 1.29°; buccolingual inclination, 1.51° vs 1.41°). CONCLUSIONS: Because the estimation errors of the root axis angle using the 3D tooth model by the WSS and LSS methods were within the clinically acceptable range, the root axis can be estimated by both methods.


Assuntos
Modelos Dentários , Raiz Dentária , Tomografia Computadorizada de Feixe Cônico , Humanos , Maxila/diagnóstico por imagem , Coroa do Dente/diagnóstico por imagem , Raiz Dentária/diagnóstico por imagem
11.
Stomatologiia (Mosk) ; 99(5): 32-37, 2020.
Artigo em Russo | MEDLINE | ID: mdl-33034174

RESUMO

THE AIM OF THE STUDY: Was to identify the features of the anatomical structure of the root canals of teeth according to CBCT data in patients in different age groups. MATERIAL AND METHODS: Patients of europeoid race, both sexes, who have indications for endodontic treatment (60 people), were divided into three groups: group 1 (young) 20 people aged 18 to 44 years, group 2 (middle age) 20 people - from 45 to 60 years, group 3 (elderly) 20 people - from 61 to 75 years old. To assess the root canal anatomy, all patients underwent x-ray examination (CT) on a Vatech computed tomography and analyzed with the Ez3D plus program before beginning endodontic treatment. The object of study was the first molars of the lower jaw (distal root canal). RESULTS: The analysis of axial, sagittal, coronal sections of the first molar of the lower jaw revealed that patients belonging to the 1st group, the distal root canal often had an oval shape all over (95%) and over a wide apical opening, in only one case out of 20 (5%) were identified at slit-like form of the distal root canal, probably due to malocclusion or as a consequence of increased abrasion of teeth. In group 2, two independent root canals were identified in the distal root of the first lower molar (in 65%), extending from the tooth cavity to the apex.in 35% of cases, the distal root canal began with a single entrance in the oral part and bifurcated into two separate channels at about the level of 2 /3 canals, then re - joined into a single apical opening, in group 3, in 75% of cases, a slit-like form of the distal root canal was observed. The obtained CLCT data (taking into account the image error) were confirmed in the clinic at the stage of endodontic treatment using optical magnification (microscope). CONCLUSION: CBCT and operation microscopy with x40 magnification data showed clear age-dependent variations of first lower molar distal root canal anatomy.


Assuntos
Cavidade Pulpar , Mandíbula , Adolescente , Adulto , Idoso , Cavidade Pulpar/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dente Molar/diagnóstico por imagem , Tratamento do Canal Radicular , Raiz Dentária/diagnóstico por imagem , Adulto Jovem
12.
Am J Orthod Dentofacial Orthop ; 158(6): 783-798.e20, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33077369

RESUMO

INTRODUCTION: Safe zone maps are useful for the clinician to plan miniscrew insertion and possibly reduce radiation exposure. This study aimed to investigate the available evidence regarding the presence of sufficient interradicular space and adequate cortical bone thickness in patients with a complete permanent dentition, in the vestibular and palatal or lingual interradicular sites, mesial to the second molar. METHODS: PubMed, Scopus, Web of Science, Cochrane Library, and OpenGrey databases were searched up to January 2019 for observational studies involving patients with fully erupted second molars that investigated the amount of interradicular space and/or the cortical thickness of the alveolar processes using 3-dimensional data sets. A custom tool was prepared and used to assess the risk of bias in individual studies. A meta-analysis was performed when at least 4 different studies evaluated 1 identical parameter homogeneously. Publication bias was assessed with the Egger linear regression test. RESULTS: Twenty-seven observational articles were included in the qualitative synthesis. Only 11 articles were at low risk of bias. Fifteen articles were included in the meta-analysis. The results were graphically reported in "safe-zone" maps. CONCLUSIONS: In the maxilla, the most suitable insertion sites are those from mesial to the first molar to distal to the first premolar, and between the canine and the lateral incisor, all at 6 mm from the cementoenamel junction. In those areas, the cortical bone has adequate thickness, not requiring predrilling. In the mandible, the preferable vestibular interradicular spaces are those between first and second molars and between first and second premolars, both at 5 mm from the cementoenamel junction, and predrilling is suggested in these areas. TRIAL REGISTRATION NUMBER: PROSPERO CRD42016042081.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Raiz Dentária , Osso Cortical/diagnóstico por imagem , Humanos , Mandíbula/diagnóstico por imagem , Maxila/diagnóstico por imagem , Raiz Dentária/diagnóstico por imagem
13.
Indian J Dent Res ; 31(4): 656-661, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33107474

RESUMO

Palatoradicular grooves are usually found on the palatal or lateral roots of maxillary central and lateral incisors. Since clinical identification of these grooves are inaccessible and arduous in routine oral hygiene practices and are susceptible alcoves for microorganism habituation and plaque accumulation, it may result in acute to severe periodontitis and, if untreated, periapical pathosis also. This paper discusses about a female patient who reported pus discharge in left upper lateral incisor. Based on history, clinical examination and IOPA (intra-oral periapical radiograph), a deep pocket of about 10-14 mm was noticed in the left upper lateral incisor. A timely investigation was made and was treated surgically with advanced modified procedures which include odontoplasty and restoration of the defect with Platelet Rich Fibrin. After follow up of 6 months, the patient reported no signs of disease progression, had good oral hygiene and the tooth remained to be vital.


Assuntos
Placa Dentária , Raiz Dentária , Feminino , Humanos , Incisivo , Maxila , Palato , Raiz Dentária/diagnóstico por imagem
14.
Endodoncia (Madr.) ; 38(2): 20-25, oct. 2020. ilus
Artigo em Espanhol | IBECS | ID: ibc-198456

RESUMO

INTRODUCCIÓN: El primer molar superior se caracteriza por tener 3 raíces y cuatro conductos radiculares. La presencia de cuatro raíces es un hallazgo inusual, pocas veces reportado en la literatura. CASO CLÍNICO: Acude a la consulta un paciente caucásico con pulpititis irreversible del 2.6. Se decide iniciar el trata-miento de conductos, pero dada la diferente morfología radicular visible radiográficamente, se realiza una CBCT previa. En el corte axial, se aprecian 4 raíces, con ápices totalmente independientes. Además, la raíz mesiovestibular presenta un único conducto y forma redondeada. Con la ayuda del microscopio se realiza una apertura inusual y se localizan los cuatro conductos. Finalizadas la instrumentación, irrigación y obturación, se recubre el acceso cameral con composite, para la posterior realización de una incrustación, capaz de sellar la caries cervical y restaurar los puntos de contacto. En el control 2 años posterior, el paciente está totalmente asintomático y la restauración demuestra su funcionalidad y estética. CONCLUSIÓN: Las anomalías anatómicas pueden presentar-se en cualquier diente. Encontrar un primer molar superior con más de tres raíces es un hallazgo muy extraño, pero gracias a la ayuda de la radiología tridimensional, se pudo visualizar y tratar de forma adecuada. Ante cualquier imagen radiográfica donde no se pueda apreciar con claridad la anatomía dental a tratar, debemos realizar varias proyecciones radiográficas o una CBCT para poder conocer la morfología real a la que nos enfrentamos


INTRODUCTION: The upper first molar is characterized by having three roots and four root canals. The presence of four roots is an unusual finding, rarely reported in the literature. CLINICA CASE: A caucasian patient with irreversible pulpititis of 2.6 comes to the dental clinic. It was decided to start the root canal treatment, but due to the different root morphology visible radiographically, a previous CBCT was performed. In the axial section, 4 roots are seen, with completely independent apexes. Furthermore, the mesiovestibular root has a single canal and a rounded shape. With the help of the microscope, an unusual opening is made and the four canals are located. After the instrumentation, irrigation and obturation are completed, the cameral access is covered with composite, for the subsequent inlay, capable of sealing cervical caries and restoring the contact points. In the control 2 years later, the patient is completely asymptomatic and the restoration demonstrates its functionality and aesthetics. CONCLUSIONS: Anatomic anomalies occur in any tooth. Finding an upper first molar with more than three roots is a very strange finding, but thanks to the help of three-dimensional radiology, it was able to be properly visualized and treated. Before any radiographic image where the dental anatomy to be treated cannot be clearly seen, we must carry out several radiographic projections or a CBCT to be able to know the real morphology that we are facing


Assuntos
Humanos , Masculino , Adulto , Tratamento do Canal Radicular/métodos , Dente Molar/cirurgia , Restauração Dentária Permanente/métodos , Radiografia Dentária , Raiz Dentária/diagnóstico por imagem , Tomografia Computadorizada de Feixe Cônico , Resultado do Tratamento
15.
Quintessence Int ; 51(10): 798-807, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32954388

RESUMO

OBJECTIVES: The purpose of this study was to assess the prevalence of C-shaped canals in permanent mandibular second molars (SMs) and to determine whether its appearance was associated with the presence of distolingual root (DLR) in permanent mandibular first molars (FMs). METHOD AND MATERIALS: Three hundred and eighty patients were qualified for evaluation of their FMs and SMs using cone beam computed tomography. The prevalence, distribution pattern, external root morphology, and the internal root canal anatomy of the examined molars were recorded and analyzed. Furthermore, the association between the root canal configurations of SMs and the appearance of DLR in FMs was also assessed. RESULTS: The prevalence of SMs with C-shaped root canals was 44.7%. The most common root canal configuration type of the one-rooted SMs with C-shaped anatomy was C3 (45.6%), followed by C2 and C1. The frequency of C-shaped canals in SMs was 45.4% in Non-DLR group, 52.8% in unilateral DLR group, and 33.9% in bilateral DLR group, respectively. Moreover, the prevalence of C-shaped root canals in SMs with the presence of bilateral DLRs in FMs was significantly lowered. CONCLUSION: The association between the presence of DLR in FMs and C-shaped canal configurations in neighboring SMs was surveyed, and the prevalence of C-shaped root canals in SMs with the presence of bilateral DLRs in FMs was found to be significantly lowered.


Assuntos
Tomografia Computadorizada de Feixe Cônico Espiral , Tomografia Computadorizada de Feixe Cônico , Cavidade Pulpar/diagnóstico por imagem , Humanos , Mandíbula/diagnóstico por imagem , Dente Molar/diagnóstico por imagem , Raiz Dentária/diagnóstico por imagem
16.
PLoS One ; 15(9): e0239759, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32970759

RESUMO

OBJECTIVE: The purpose of this study was to evaluate the effects of miniscrew insertion angle and vertical facial type on the interradicular miniscrew-root distance available for molar distalization. MATERIALS AND METHODS: Cone-beam computed tomography images of 60 adults with skeletal Class I occlusion exhibiting hyperdivergent (n = 20), normodivergent (n = 20), and hypodivergent (n = 20) facial types were used. Placement of a 6-mm long, 1.5-mm diameter, tapered miniscrew was simulated at a site 4 mm apical to the cementoenamel junction, with insertion angles of 0°, 30°, 45°, and 60° relative to the transverse occlusal plane. The shortest linear distance between the miniscrew and anterior root at four interradicular sites was measured: maxillary second premolar and first molar (Mx 5-6), maxillary first and second molars (Mx 6-7), mandibular second premolar and first molar (Mn 5-6), and mandibular first and second molars (Mn 6-7). RESULTS: Miniscrew-root distance significantly increased as the insertion angle increased from 0° to 60°. In the mandible, the distances significantly differed among vertical facial types, increasing in the following order: hyperdivergent, normodivergent, and hypodivergent. The minimum mean distance was found in the Mx 6-7 (30°; 0.86±0.35 mm), and the maximum mean distance was found in the Mn 5-6 (60°; 2.64±0.56 mm). The rates of miniscrews located buccally outside the root distalization path were up to 70% and 55% when the miniscrews were placed at 60° insertion angles in the Mx 5-6 and Mn 5-6 regions, respectively. CONCLUSIONS: Miniscrew-root distance increased significantly with the increased insertion angle, and the amount of increase was affected by the miniscrew placement site and vertical facial type. To ensure adequate distalization of the posterior segment, the miniscrew should be inserted at an angle in the interradicular area between the second premolar and first molar.


Assuntos
Parafusos Ósseos , Simulação por Computador , Tomografia Computadorizada de Feixe Cônico/métodos , Dente Molar/diagnóstico por imagem , Procedimentos de Ancoragem Ortodôntica/métodos , Técnicas de Movimentação Dentária/métodos , Raiz Dentária/diagnóstico por imagem , Adulto , Feminino , Humanos , Masculino , Procedimentos de Ancoragem Ortodôntica/instrumentação , Técnicas de Movimentação Dentária/instrumentação
17.
Int J Nanomedicine ; 15: 6761-6777, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32982232

RESUMO

Purpose: Guided bone regeneration (GBR) therapy, which is a widely used technique in clinical practice and is effective in improving the repair of alveolar bone defects or bone mass deficiency regeneration, requires the use of membrane materials with good biocompatibility, barrier function, rigidity matching the space maintenance ability, economic benefits and excellent clinical applicability. The aim of this study was to develop an electrospun attapulgite (ATT)-doped poly (lactic-co-glycolic acid) (PLGA) scaffold (PLGA/ATT scaffold) as a novel material for GBR applications. Methods and Results: Scanning electron microscopy (SEM) and X-ray diffraction (XRD) were used to determine the morphology and the crystalline structure of the PLGA/ATT scaffolds, respectively. Porosity and contact-angle measurements were also carried out to further characterize the physical properties of the PLGA/ATT scaffolds. The results of in vitro studies showed that bone marrow mesenchymal stem cells (BMSCs) attached more readily to and spread better over the PLGA/ATT scaffolds than the Bio-Gide membrane. Furthermore, in the in vitro osteoinductive experiments with BMSCs, the PLGA/ATT scaffolds were found to enhance the activity of alkaline phosphatase (ALP), promote the formation of mineralized bone nodules, and up-regulate the expression of several osteogenic markers-namely, runt-related transcription factor 2, alkaline phosphatase, osteopontin, and osteocalcin-which are similar to the effects of the Bio-Gide membrane. Further, in in vivo studies, the results of sequential fluorescent labeling, micro-computed tomography, and histological analysis suggest that using the PLGA/ATT scaffolds for repairing V-shaped buccal dehiscence on a dog's tooth root improved bone regeneration, which is not only similar to the result obtained using the Bio-Gide membrane but also much better than that obtained using PLGA scaffolds and the negative control. Conclusion: To achieve satisfactory therapeutic results and to lower the cost of GBR treatment, this study provided a promising alternative material of bio-degradable membrane in clinical treatment.


Assuntos
Perda do Osso Alveolar/terapia , Regeneração Óssea/fisiologia , Compostos de Magnésio/farmacologia , Compostos de Silício/farmacologia , Tecidos Suporte/química , Animais , Regeneração Óssea/efeitos dos fármacos , Calcificação Fisiológica , Colágeno , Cães , Expressão Gênica , Gengiva/citologia , Humanos , Compostos de Magnésio/química , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/fisiologia , Osteogênese/efeitos dos fármacos , Osteogênese/genética , Osteogênese/fisiologia , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Porosidade , Ratos Sprague-Dawley , Compostos de Silício/química , Raiz Dentária/diagnóstico por imagem , Microtomografia por Raio-X
18.
Arch Oral Biol ; 117: 104792, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32559509

RESUMO

OBJECTIVES: The aim of the present study was to evaluate the influence of bifid and non-bifid configurations of the mesial root of mandibular first molars in the canal anatomy using micro-computed tomography (micro-CT). DESIGN: Thirty mesial roots with bifid apex were pair-matched with 30 non-bifid roots by means of micro-CT. Bifid and non-bifid mesial roots were compared regarding morphological aspects at the apical third, dentin thickness, and the presence of isthmus and middle mesial canal (MMC). Data were analyzed using Chi-square test and Student's t-test with a significant level of 5 %. RESULTS: Main foramen of mesiobuccal (MB) and mesiolingual (ML) canals were positioned within 2.5 mm from the anatomic apex, and origin and exit of accessory canals were observed mostly between 1.0 and 2.0 mm from the apex in the groups. Despite no statistical difference was observed between bifid and non-bifid roots regarding the number of canal orifices (p > 0.05), the frequency of accessory canals was significantly higher in bifid roots (p < 0.05). Regarding the dentin thickness, a statistically significant difference was observed between bifid and non-bifid roots at the furcation level (p < 0.05). Only 3 mesial roots with bifid apex (10 %) had isthmuses, mostly at the coronal third, while a high incidence of MMC was observed in this group (n = 10, 33.3 %). CONCLUSIONS: Presence of bifid apex in the mesial root of mandibular first molars might be a predictive factor for a complex canal anatomy at the apical third with an increasing number of accessory canals.


Assuntos
Dente Molar , Raiz Dentária/diagnóstico por imagem , Cavidade Pulpar/diagnóstico por imagem , Humanos , Mandíbula/diagnóstico por imagem , Dente Molar/diagnóstico por imagem , Ápice Dentário/diagnóstico por imagem , Microtomografia por Raio-X
19.
Artigo em Inglês | MEDLINE | ID: mdl-32546427

RESUMO

OBJECTIVE: The aim of this study was to examine the relationship between molar root positions and antral pseudocysts (APs). STUDY DESIGN: The retrospective study included 160 patients. Vertical relationships of the molar roots and the maxillary sinus floor were divided into 4 categories. Root relationships were compared for the presence and dimensions of APs overlying teeth. The root relationships and the presence of APs were also compared for differences in gender, right versus left side, and age groups. RESULTS: APs were significantly more likely to occur in areas where 1 root extended through the sinus floor from the first molar (P = .004) or second molar (P = .014) and where more than 1 root of the first molar extended through the floor (P = .002). The extension of roots into the sinus was associated with a 9.900 to 25.300 times increase in APs compared with areas with no root contact. The height and width of APs were significantly greater in areas of root penetration into the sinus but gender, side, and age had no effect on the distribution of these root relationships. CONCLUSIONS: Root apices that transmit occlusal force to the Schneiderian membrane might induce the formation of APs and increase the dimensions of the lesions.


Assuntos
Seio Maxilar , Levantamento do Assoalho do Seio Maxilar , Tomografia Computadorizada de Feixe Cônico , Humanos , Maxila , Seio Maxilar/diagnóstico por imagem , Dente Molar/diagnóstico por imagem , Estudos Retrospectivos , Raiz Dentária/diagnóstico por imagem
20.
BMC Oral Health ; 20(1): 135, 2020 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-32384929

RESUMO

BACKGROUND: While there is ample research into the anatomy of mandibular molars, little is known regarding isthmuses and middle mesial (MM) canals in Chinese populations. The goal of this study was to determine the prevalence of MM canals and isthmuses in the mesial root of mandibular first molars using Cone-beam Computed Tomography. METHODS: Cone-beam Computed Tomography images of 357 mature mandibular first molars were retrospectively analyzed. Presence of isthmuses and MM canals, and the length of isthmuses in the mesial root were recorded. Meanwhile, we also recorded possible correlated factors such as demographics, side of mandible, presence of separated distal-lingual roots. RESULTS: Of these 357 teeth, 209 showed evidence of either complete or partial communication in the mesial root. Of these, 11(3.1%) exhibited true MM canals while 198(55.5%) exhibited isthmuses. Sex or side of mandible was not correlated with the prevalence of isthmuses (P > 0.05). However, there was a significant association between the presence of a distal-lingual root and the prevalence of such communication (P < 0.001). The average length of isthmuses was 4.3 ± 3.1 mm. CONCLUSIONS: We detected high rate of isthmuses and low rate of MM canals in mesial roots of mandibular first molars, which is important as such areas should be identified and cleaned during root canal treatment.


Assuntos
Tomografia Computadorizada de Feixe Cônico/métodos , Cavidade Pulpar/diagnóstico por imagem , Mandíbula/diagnóstico por imagem , Dente Molar/diagnóstico por imagem , Raiz Dentária/diagnóstico por imagem , Adolescente , Adulto , Idoso , Grupo com Ancestrais do Continente Asiático , China , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
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