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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 -
Journal of Applied Microbiology Jan 2023Long-term retention of impacted third molars (wisdom teeth) is associated with plaque stagnation and the development of caries on the adjacent surface of the neighboring...
AIMS
Long-term retention of impacted third molars (wisdom teeth) is associated with plaque stagnation and the development of caries on the adjacent surface of the neighboring second molar. While caries and tooth loss are common outcomes of impaction, there is currently insufficient evidence to support the pre-emptive removal of asymptomatic wisdom teeth. Emerging evidence suggests that convergently growing impactions are associated with caries. We have therefore investigated the composition of dental plaque on the distal surface of the mandibular second molar at various impaction angles.
METHODS AND RESULTS
We have compared the microbiome of these surfaces at four impaction angulations using short-read sequencing of the bacterial 16S rRNA gene: two convergent (horizontal and mesial) and two divergent (distal and vertical) angulations, and in cases where the wisdom tooth is missing. Horizontal angulations exhibited lower microbial diversity than mesial impactions. Amplicon Sequence Variants (ASVs) associated with Veillonella were significantly more abundant at impactions with angulations toward the midline. Using machine learning, a random forest classifier trained to distinguish microbiome profiles was used to predict the native angulations for a subset of samples, with samples from the two convergent impactions estimated with the greatest accuracy.
CONCLUSIONS
Differences in microbial diversity were apparent between caries-associated convergent (horizontal and mesial) impacted wisdom teeth, as well as greater abundances of Veillonella ASVs at horizontal impactions.
Topics: Humans; Molar, Third; RNA, Ribosomal, 16S; Tooth, Impacted; Evidence Gaps
PubMed: 36626760
DOI: 10.1093/jambio/lxac054 -
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 -
British Journal of Neurosurgery Oct 2023The contralateral transfalcine approach is a valuable option to access lesions around the mesial surface of the brain hemispheres. Despite a favourable perspective,...
The contralateral transfalcine approach is a valuable option to access lesions around the mesial surface of the brain hemispheres. Despite a favourable perspective, surgical manoeuvres within the interhemispheric fissure carry a risk of inadvertent injury to the healthy cortex on the craniotomy side. To overcome this drawback, a new method of brain retraction was developed. After dissecting the interhemispheric fissure, the falx was incised in an upside-down U-shaped manner and hinged inferiorly, taking care not to violate the inferior sagittal sinus. The falcine flap was reflected laterally and fixed to the lateral edge of the craniotomy, providing homogeneous retraction of the ipsilateral mesial cortex. Surgery proceeded with the brain surface hidden from the surgeon's view and protected by the flap. The absence of retractor devices hindering the surgeon's movements further simplified the procedure.
Topics: Humans; Neurosurgical Procedures; Craniotomy; Cerebral Cortex; Dura Mater; Brain
PubMed: 33590798
DOI: 10.1080/02688697.2021.1878108 -
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 -
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 -
Journal of Prosthodontics : Official... Mar 2022Error testing at each stage of prosthetic manufacturing remains relatively underdeveloped for computer-aided design/computer-aided manufacturing methods, and no...
PURPOSE
Error testing at each stage of prosthetic manufacturing remains relatively underdeveloped for computer-aided design/computer-aided manufacturing methods, and no experimental studies have validated the computer-aided design programs. This study aimed to test the accuracy and trueness of the computer-aided design of a three-unit fixed prosthesis.
MATERIALS AND METHODS
Three computer-aided design programs (Exocad, Dental System™, and inLab 16) were tested on the designs of a three-unit fixed partial denture, and a three-dimensional analysis program was used to calculate the internal clearance error for the computer-aided design prostheses. The Kruskal-Wallis and Dunn's post hoc tests were used to reveal significant differences in trueness between the three computer-aided design programs (α < 0.05).
RESULTS
Dental System™ showed the lowest mean error values for #24 and #26 at the mesial margin (both 0 µm), mesial wall (0.10, 0.12 µm, respectively), occlusal surface (-0.05, 0.10 µm), distal wall (0.23, -0.02 µm), and distal margin (both 0 µm). In sum, except for the mesial margin and distal margin site of tooth #26, the mean error value of Dental System™ was statistically the lowest, followed by those of Exocad and inLab 16 (p < 0.003).
CONCLUSIONS
The accuracy of computer-aided design differed according to the type of computer-aided design program. Dental System™ achieved the best trueness at the margins, axial walls, and occlusal surface, followed by Exocad and inLab 16.
Topics: Computer-Aided Design; Dental Marginal Adaptation; Dental Materials; Dental Prosthesis Design; Denture, Partial, Fixed; Zirconium
PubMed: 34310790
DOI: 10.1111/jopr.13406 -
International Journal of Dental Hygiene May 2022The authors hypothesize that periodontal and peri-implant inflammatory parameters are poorer in adult patients with tongue piercing compared with controls. The aim was...
OBJECTIVES
The authors hypothesize that periodontal and peri-implant inflammatory parameters are poorer in adult patients with tongue piercing compared with controls. The aim was to assess the influence of tongue piercing on periodontal and peri-implant health status in adults.
METHODS
Test and control groups comprised of individuals with and without tongue piercing, respectively. A questionnaire was used to collect information about gender, age, duration of tongue piercing and implants in function, jaw location of the implant, reasoning for wearing the tongue ornament, and oral hygiene and ornament cleaning habits. Full-mouth and peri-implant plaque index (PI), gingival index (GI), clinical attachment loss (CAL), probing depth (PD) and marginal/crestal bone loss (MBL and CBL, respectively) on mesial and distal surfaces of teeth/implants were recorded. The material (plastic or metal) from which, the bar and ball-ends of the ornament were fabricated was also recorded. A p < 0.01 was considered statistically significant.
RESULTS
Forty-eight and 49 individuals were included in the test and control groups, respectively. There was no difference in PI, GI, PD, CAL and MBL (mesial and distal) among individuals in the test and control groups. In the test group, peri-implant PI (p < 0.01), GI (p < 0.01), PD (p < 0.01) and mesial (p < 0.01) and distal (p < 0.01) CBL were significantly higher in the anterior mandible compared with implants in other jaw locations. In the control group, there was no difference in peri-implant PI, GI, PD and CBL around implants placed in both jaws.
CONCLUSION
Wearing tongue piercings could increase the risks of periodontal and peri-implant diseases particularly in the mandibular anterior segment.
Topics: Adult; Alveolar Bone Loss; Body Piercing; Case-Control Studies; Cross-Sectional Studies; Dental Implants; Follow-Up Studies; Humans
PubMed: 33773044
DOI: 10.1111/idh.12499