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Folia Morphologica 2022The aim of the study was to analyse the morphology of the apical foramen in permanent maxillary and mandibular human teeth.
BACKGROUND
The aim of the study was to analyse the morphology of the apical foramen in permanent maxillary and mandibular human teeth.
MATERIALS AND METHODS
The anatomic parameters include shapes (rounded, oval, uneven, flat and semilunar) and location (centre, buccal/labial, lingual/palatal, mesial, and distal) of the apical foramina was evaluated. The shapes and locations of apical foramen were analysed based on tooth type (central incisor, lateral incisor, canine, premolars, and molars) arch type (maxillary and mandibular), and position (anterior and posterior). All the teeth were investigated for the apical foramina shape and location using a stereomicroscope at a magnification of 10×. Descriptive statistics performed using SPSS (Version 21.0, IBM, NY, USA) at p value less than 0.05.
RESULTS
The common shape of apical foramina was round (65%) and location was centre (32%). The frequency of deviation of apical was 68% in overall teeth. Apical foramina in maxillary anterior teeth showed more deviation while posterior teeth in mandibular teeth. The most common shape of apical foramina was round (65.1%) followed by (31%) and flat and semilunar shapes are very rare in studied subjects.
CONCLUSIONS
The most frequent direction of deviation is the distal surface, followed by the mesial surface. The variation is more common in mandibular posterior teeth, while maxillary posteriors showed the least difference. The commonest shape of the apical foramen is of a round shape, followed by the oval. The oval shape of the apical foramen is most frequent with central incisors.
Topics: Bicuspid; Humans; Mandible; Maxilla; Molar; Tooth Apex
PubMed: 33330969
DOI: 10.5603/FM.a2020.0143 -
BMC Oral Health Sep 2023This study aimed to assess the root canal morphology of primary molars using cone-beam computed tomography (CBCT).
BACKGROUND
This study aimed to assess the root canal morphology of primary molars using cone-beam computed tomography (CBCT).
METHODS
This cross-sectional study evaluated 60 maxillary and mandibular primary first and second molars on CBCT scans of patients retrieved from the archives of Hamadan School of Dentistry between 2018-2020. The teeth were evaluated regarding the number of roots and canals, canal type according to the Vertucci's classification, and root surface concavities. Data were analyzed descriptively and by independent t-test.
RESULTS
The most frequent number of canals and roots in the maxillary right and left first molars was 3 canals (60%) and 3 roots (80%). These values were 4 canals (80%) and 5 canals (50%) with 3 roots in the maxillary right and left second molars, respectively, 4 canals (100%) and 2 roots (50%), and 3 canals (60%) and 2 roots (50%) in mandibular right and left first molars, respectively, and 4 canals (92.3%) and 3 roots (61.5%) in mandibular right and left second molars. Vertucci's type IV was the most common canal type in mesial and distal canals, type I was the most common in mesiobuccal, mesiolingual, distobuccal, and distolingual, and types I and II were the most common in the palatal canal. The maximum and minimum concavities were noted in the buccal (26.7%) and mesial (8.3%) surfaces, respectively.
CONCLUSIONS
A wide variation exists in the number of roots and canals of maxillary and mandibular primary molars, which calls for further attention in treatment of such teeth.
Topics: Humans; Dental Pulp Cavity; Cross-Sectional Studies; Root Canal Therapy; Molar; Cone-Beam Computed Tomography
PubMed: 37749546
DOI: 10.1186/s12903-023-03414-z -
Journal of Conservative Dentistry : JCD 2022This study aimed to evaluate the shaping ability of TruNatomy (Dentsply Maillefer, Ballaigues, Switzerland), VDW.ROTATE (VDW GmbH, Munich, Germany) and ProTaper Gold...
INTRODUCTION
This study aimed to evaluate the shaping ability of TruNatomy (Dentsply Maillefer, Ballaigues, Switzerland), VDW.ROTATE (VDW GmbH, Munich, Germany) and ProTaper Gold (Dentsply Maillefer, Ballaigues, Switzerland) during the preparation of resin-printed mandibular molar mesial root canals.
MATERIALS AND METHODS
Thirty-three printed resin-based mandibular mesial roots with two canals were obtained from extract tooth cone-beam computed tomography (CBCT) image. The printed teeth were divided into three groups ( = 11) according to the system used for root canal preparation: TruNatomy, VDW.ROTATE, and ProTaper Gold. The specimens were scanned using CBCT imaging before and after root canal preparation. Then images were registered using a dedicated software and changes in the canal area, volume, untouched canal surface, and the maximum and minimum dentin wall wear were calculated.
STATISTICAL ANALYSIS USED
Data were statistically analyzed using Shapiro-Wilk for normality, one-way ANOVA, and Tukey or Kruskal-Wallis H tests with alpha set at 5%.
RESULTS
No differences were observed for changes in the canal area, volume, untouched canal surface area, and minimum dentine wall wear parameters for the whole canal length ( > 0.05). The mean of untouched canal surface area for the TruNatomy, VDW.ROTATE, and ProTaper Gold was 40%, 44%, and 44%, respectively. The maximum dentine wall wear was significantly lower in the ProTaper Gold group than in the TruNatomy and VDW.ROTATE groups ( < 0.05).
CONCLUSIONS
TruNatomy, VDW.ROTATE, and ProTaper Gold systems showed similar shaping ability in printed resin-based mandibular mesial roots without clinically significant errors. A large amount of untouched canal surface area was observed for all systems.
PubMed: 36506631
DOI: 10.4103/jcd.jcd_251_22 -
Brazilian Dental Journal 2021The aim of this study was to evaluate surface wear, presence of microcracks and surface irregularities of WaveOne (WO) and WaveOne Gold (WOG) instruments before and...
The aim of this study was to evaluate surface wear, presence of microcracks and surface irregularities of WaveOne (WO) and WaveOne Gold (WOG) instruments before and after multiple uses. Eight Primary instruments of the WO and WOG systems were evaluated, each one was used to prepare six mesial canals of extracted human mandibular molars. The surface of the instruments was evaluated before use (T0), after instrumentation of three (T1) and six (T2) root canals. Surface wear was analyzed using a three-dimensional optical profiler and the presence of microcracks and surface irregularities were evaluated using a tabletop scanning electron microscopy. The Friedman test was used to assess surface wear and Kruskal-Wallis test to evaluate the presence of microcracks and surface irregularities, with a 5% significance level. There was a significant increase in wear in both groups at T2, compared to T0 (p=0.0003). The surface wear after instrumentation of six canals (T2-T0) was statistically greater in the WOG group, than in the WO group (p=0.02), where the presence of microcracks was significantly greater and increased after multiple uses (p<0.05). The presence of surface irregularities in the cutting blade before and after use was statistically greater in the WOG group than WO group (p<0.05). Wear of the cutting blade, microcracks and surface irregularities were observed on the surface topography of all the instruments after multiple uses. These surface changes may affect the cutting efficiency of WOG files and increase the risk of fracture of WO files.
Topics: Dental Instruments; Dental Pulp Cavity; Equipment Design; Hot Temperature; Humans; Nickel; Root Canal Preparation; Titanium
PubMed: 35019022
DOI: 10.1590/0103-6440202104045 -
Quantitative Imaging in Medicine and... Apr 2015Currently, a relevant proportion of all histopathologically proven focal cortical dysplasia (FCD) escape visual detection; this shows the need for additional... (Review)
Review
Currently, a relevant proportion of all histopathologically proven focal cortical dysplasia (FCD) escape visual detection; this shows the need for additional improvements in analyzing MRI data. A positive MRI is still the strongest prognostic factor for postoperative freedom of seizures. Among several post-processing methods voxel-based morphometry (VBM) of T1- and T2-weighted sequences and T2 relaxometry are routinely applied in pre-surgical diagnostics of cryptogenic epilepsy in epilepsy centers. VBM is superior to conventional visual analysis with 9-15% more identified epileptogenic foci, while T2 relaxometry has its main application in (mesial) temporal lobe epilepsy. Further methods such as surface-based morphometry (SBM) or diffusion tensor imaging are promising but there is a lack of current studies comparing their individual diagnostic value. Post-processing methods represent an important addition to conventional visual analysis but need to be interpreted with expertise and experience so that they should be apprehended as a complementary tool within the context of the multi-modal evaluation of epilepsy patients. This review will give an overview of existing post-processing methods of structural MRI and outline their clinical relevance in detection of epileptogenic structural changes.
PubMed: 25853079
DOI: 10.3978/j.issn.2223-4292.2015.01.10 -
Journal of Integrative Neuroscience Mar 2021The superior parietal lobule of the macaque monkey occupies the postero-medial part of the parietal lobe and plays a crucial role in the integration of different sources... (Review)
Review
The superior parietal lobule of the macaque monkey occupies the postero-medial part of the parietal lobe and plays a crucial role in the integration of different sources of information (from visual, motor and somatosensory brain regions) for the purpose of high-level cognitive functions, as perception for action. This region encompasses the intraparietal sulcus and the parieto-occipital sulcus and includes also the precuneate cortex in the mesial surface of the hemisphere. It hosts several areas extensively studied in the macaque: PE, PEip, PEci anteriorly and PEc, MIP, PGm and V6A posteriorly. Recently studies based on functional MRI have suggested putative human homologue of some of the areas of the macaque superior parietal lobule. Here we review the anatomical subdivision, the cortico-cortical and thalamo-cortical connections of the macaque superior parietal lobule compared with their functional properties and the homology with human organization in physiological and lesioned situations. The knowledge of this part of the macaque brain could help in understanding pathological conditions that in humans affect the normal behaviour of arm-reaching actions and can inspire brain computer interfaces performing in more accurate ways the sensorimotor transformations needed to interact with the surrounding environment.
Topics: Animals; Cerebral Cortex; Humans; Macaca; Mental Processes; Motor Activity; Nerve Net; Parietal Lobe; Thalamus
PubMed: 33834704
DOI: 10.31083/j.jin.2021.01.334 -
Wiadomosci Lekarskie (Warsaw, Poland :... 2021The aim: To study the odontoglific and odometometric parameters of molar crowns of the upper and lower jaws in males and females.
OBJECTIVE
The aim: To study the odontoglific and odometometric parameters of molar crowns of the upper and lower jaws in males and females.
PATIENTS AND METHODS
Materials and methods: To achieve the aim of the research was used odontoglyphic, odometometric and statistical methods of research.
RESULTS
Results: We have found that male molars of the upper jaw are characterized by approximately the same ratio between the vestibular-palatal and mesial-distal diameters of the crown, so the teeth are square-formed. For female large angular teeth of the upper jaw the predominance of vestibular-palatal over mesial-distal diameters of the crown is characteristic, which results in an oval form of the teeth. On having analyzed the forms of the third lower molars, it can be affirmed that for this group of teeth various variational forms of crowns, from three- to five-tuber forms, are characteristic. Vestibular-lingual and mesio-distal sizes also vary according to the type of odontoglific pattern of occlusal crown surface.
CONCLUSION
Conclusions: We consider it expedient to take into account the abovementioned characteristics of the masticatory surface of molars of the upper and lower jaws of male and female persons for the creation of qualitative orthopedic structures that would fully restore the masticatory function.
Topics: Crowns; Dental Clinics; Female; Humans; Male; Mandible; Maxilla; Molar
PubMed: 34090277
DOI: No ID Found -
European Journal of Dentistry Sep 2023The aim of this study was to analyze the internal morphology of deciduous molars through the use of computed microtomography in a sample from Rio de Janeiro.
OBJECTIVE
The aim of this study was to analyze the internal morphology of deciduous molars through the use of computed microtomography in a sample from Rio de Janeiro.
MATERIAL AND METHODS
Thirty maxillary and 30 mandibular deciduous molars ( = 60), divided in first and second primary molars, were scanned by computed microtomography. The teeth were evaluated for root number, root canals, Vertucci classification, root curvature, presence of lateral canals, furcation dentin thickness, structure model index (SMI), volume, and canal surface area.
RESULTS
The results showed 100% of maxillary molars had three roots and Vertucci type I canal was more prevalent in this group. In the mandibular ones, type IV was more frequent in the mesial root and class I in the distal root and the cavo-interradicular canal occurred in 2 specimens. Dentin thickness in the furcation region measured 1.53 and 1.59 mm in the maxillary and mandibular, respectively. Volume and area parameters varied according to the evaluated canals and SMI demonstrated that all canals had a cylindrical shape.
CONCLUSION
More detailed information about the internal anatomy of the primary molars has been described, which may help strategies in the preparation of these root canals.
PubMed: 37729937
DOI: 10.1055/s-0043-1772566 -
Sensors (Basel, Switzerland) Sep 2019Digital dental reconstruction can be a more efficient and effective mechanism for artificial crown construction and period inspection. However, optical methods cannot...
Digital dental reconstruction can be a more efficient and effective mechanism for artificial crown construction and period inspection. However, optical methods cannot reconstruct those portions under gums, and X-ray-based methods have high radiation to limit their applied frequency. Optical coherence tomography (OCT) can harmlessly penetrate gums using low-coherence infrared rays, and thus, this work designs an OCT-based framework for dental reconstruction using optical rectification, fast Fourier transform, volumetric boundary detection, and Poisson surface reconstruction to overcome noisy imaging. Additionally, in order to operate in a patient's mouth, the caliber of the injector is small along with its short penetration depth and effective operation range, and thus, reconstruction requires multiple scans from various directions along with proper alignment. However, flat regions, such as the mesial side of front teeth, may not have enough features for alignment. As a result, we design a scanning order for different types of teeth starting from an area of abundant features for easier alignment while using gyros to track scanned postures for better initial orientations. It is important to provide immediate feedback for each scan, and thus, we accelerate the entire signal processing, boundary detection, and point-cloud alignment using Graphics Processing Units (GPUs) while streamlining the data transfer and GPU computations. Finally, our framework can successfully reconstruct three isolated teeth and a side of one living tooth with comparable precisions against the state-of-art method. Moreover, a user study also verifies the effectiveness of our interactive feedback for efficient and fast clinic scanning.
Topics: Calibration; Equipment Design; Fourier Analysis; Gingiva; Humans; Image Processing, Computer-Assisted; Tomography, Optical Coherence; Tooth
PubMed: 31569554
DOI: 10.3390/s19194234 -
Oman Medical Journal Jan 2022In the last decade, bulk-fill materials were introduced to allow resin-based composites (RBC) in one layer (up to 4-5 mm thick) with optimum polymerization. We sought to...
OBJECTIVES
In the last decade, bulk-fill materials were introduced to allow resin-based composites (RBC) in one layer (up to 4-5 mm thick) with optimum polymerization. We sought to evaluate the adaptation ability of different bulk-fill composites resin (CRs)and restoration marginal integrity.
METHODS
A total of 28 caries-free and crack-free human molars underwent mesio-occlusal-distal cavity preparation. Each sample prepared the mesial margins on enamel, and the distal margins were extended into dentin. Teeth were then randomly distributed into four groups (n = 7 per group) according to the CR used to restore the cavity. Three bulk-fill CRs-Smart Dentin Replacement Flow+, 3M™ Filtek™ One Bulk Fill (FBF), and Tetric® N-Ceram Bulk Fill (TBF)-and one conventional CR (CC)-Filtek™ Z350-were used. The teeth were then subjected to aging via thermocycling, followed by cyclic loading. Finally, the volumetric width of the interfacial gap at the tooth-restoration interface was measured using a microcomputed tomography (µ-CT) analysis.
RESULTS
SDR demonstrated the smallest gap volume among all tested CRs, followed by CC in enamel and TBF in dentin after aging. FBF showed the highest gap volume. There was no statistically significant three-way interaction between surface, aging, and material ( > 0.050).
CONCLUSIONS
It is safe to suggest using bulk-fill RBC in deep class II cavities instead of conventional layered RBC when dealing with dentin margins. However, further clinical investigation is required.
PubMed: 35211342
DOI: 10.5001/omj.2021.114