scholarly journals Efficacy of LA Axxess burs, Gates Glidden drills and Protaper Sx in obtaining straight line access in mesiobuccal roots of mandibular first molars: A cone-beam computed tomography assessment

2016 ◽  
Vol 10 (04) ◽  
pp. 486-490
Author(s):  
Promila Verma ◽  
Rhythm Bains ◽  
A. P. Tikku ◽  
Anil Chandra ◽  
Shibha Mehta

ABSTRACT Objective: This study aims at cone-beam computed tomography (CBCT) evaluation of the ability of Gates Glidden (GG) drills, Protaper Sx, and LA Axxess burs to produce a straight line access (SLA) in mesiobuccal canals of mandibular first molars. Methodology: Forty-five freshly extracted mandibular teeth with a canal curvature of 10-20° were taken for the study and divided into three groups according to the instruments used for cervical preflaring: Group I (LA Axxess burs), Group II (GG drills), and Group III (Protaper Sx). Pre- and post-instrumentation CBCT images were evaluated for comparing the ability of GG drills, Protaper Sx and LA Axxess burs to produce an SLA in mesiobuccal canals of mandibular first molars. Results: There was no significant change (P = 0.06) in the angle in the preSLA images of LA Axxess Group I (12.37 ± 1.01), GG Group II (13.39 ± 1.74), and Protaper Sx Group III (13.90 ± 1.74). The mean decrease in the angle from preSLA to postSLA was significant for all the three groups (P = 0.0001). However, the mean change was highest in Group I (4.25 ± 1.14), followed by Group II (3.28 ± 1.22) and Group III (2.89 ± 1.53). Conclusion: LA Axxess burs were the most effective in reducing the coronal curvature and produced a straighter access to apical third compared to GG Drills and Protaper Sx.

2021 ◽  
Vol 28 (1) ◽  
pp. E202114
Author(s):  
Omair Shah ◽  
Faiz Shera ◽  
Naseer Choh ◽  
Tariq Gojwari ◽  
Fahad Shafi ◽  
...  

The length of the styloid process varies greatly in different populations and depends on ethnicity and geographical background. The elongated styloid process may be associated with Eagle’s syndrome. Therefore, the mean normal length of the styloid process in different population groups needs to be calculated and the upper cutoff limit for elongated styloid process should be found. The objective of the research was to evaluate the styloid process length in the Kashmiri population using multidetector computed tomography. Materials and Methods. We retrospectively evaluated 304 patients who underwent computed tomography of the head and paranasal sinuses, and the mean styloid process length was calculated on both sides. The mean of three measurements of styloid process length was taken. The study population was grouped as follows: Group I included patients at the age of 21-30 years; Group II comprised patients at the age of 31-40 years; Group III included 68 patients at the age of 41-50 years; Group IV comprised patients > 50 years old. Results. The mean length of the styloid process in the studied population varied from 20 to 51 mm (mean 31.3 ± 4.5 mm). There was no significant difference in the length on both sides (p=0.835). The mean length of the styloid process was 30.1 ± 4.2 mm in females and 32.3 ± 4.8 mm in males (p< 0.034). The lengths of the styloid process in different age groups were as follows: in Group I - 30.9 ± 4.4 mm; in Group II - 31.2 ± 4.8 mm; in Group III - 31.6 ± 4.3 mm; in Group IV - 31.5 ± 4.5 mm. Conclusions. The mean length of the styloid process in our population was higher as compared to many other ethnic groups. The styloid process in males was longer. The elongated styloid process on computed tomography scan should not be labeled as Eagle’s syndrome unless clinical symptoms are present.


2019 ◽  
Vol 9 (4) ◽  
pp. 2-5
Author(s):  
Neera Joshi Amatya ◽  
Kranti Prajapati ◽  
Suraj Shrestha ◽  
Sharada Wagle

Background: Dimension and location of pulp chamber are important during access cavity preparation. It allows clinician in instruments selection, orientation and depth of cutting dur­ing the process. Analysis of these has been done in preoperative intraoral periapical radio­graph that gives two-dimensional image. The radiograph has been blamed now and then for the inaccurate results and iatrogenic damage occurred due to the inaccurate results. Cone-Beam Computed Tomography (CBCT) provides three-dimensional images and is taken as standard. Hence the aim of the study is to compare intra-oral periapical (IOPA) radiograph and CBCT to determine the landmarks for accurate results Methods: 50 intact two-rooted maxillary first premolars were collected and numbered. Peri­apical radiograph Images and CBCT images of these 50 teeth were taken and divided as; Group I: 50 IOPAR and Group II: 50 CBCT images. Landmarks marking and measurement was done using tracing paper and x-ray viewer for IOPA images and Planmeca Romexis software for CBCT images. Data were collected and analysed with descriptive and inferential statistics by using Statistical Package of Social Science (SPSS) software version 16. Results: The averages of group I are 7.44, 10.23mm 14.33mm, 4.1mm, 6.89mm and 2.79mm respectively. The averages of in group II are 6.95mm, 9.58mm, 14.03mm, 4.45mm, 7.07mm and 2.63mm respectively. There is statistically significant difference in measurement A and measurement B between group I and group II. Conclusions:  This indicates that there are chances of overestimation of measurement A and B with IOPAR.


Urolithiasis ◽  
2021 ◽  
Author(s):  
R. A. Kingma ◽  
M. J. H. Voskamp ◽  
B. H. J. Doornweerd ◽  
I. J. de Jong ◽  
S. Roemeling

AbstractCone beam computed tomography (CBCT) provides multiplanar cross-sectional imaging and three-dimensional reconstructions and can be used intraoperatively in a hybrid operating room. In this study, we investigated the feasibility of using a CBCT-scanner for detecting residual stones during percutaneous nephrolithotomy (PCNL). Intraoperative CBCT-scans were made during PCNL procedures from November 2018 until March 2019 in a university hospital. At the point where the urologist would have otherwise ended the procedure, a CBCT-scan was made to image any residual fragments that could not be detected by either nephroscopy or conventional C-arm fluoroscopy. Residual fragments that were visualized on the CBCT-scan were attempted to be extracted additionally. To evaluate the effect of this additional extraction, each CBCT-scan was compared with a regular follow-up CT-scan that was made 4 weeks postoperatively. A total of 19 procedures were analyzed in this study. The mean duration of performing the CBCT-scan, including preparation and interpretation, was 8 min. Additional stone extraction, if applicable, had a mean duration of 11 min. The mean effective dose per CBCT-scan was 7.25 mSv. Additional extraction of residual fragments as imaged on the CBCT-scan occurred in nine procedures (47%). Of the follow-up CT-scans, 63% showed a stone-free status as compared to 47% of the intraoperative CBCT-scans. We conclude that the use of CBCT for the detection of residual stones in PCNL is meaningful, safe, and feasible.


2004 ◽  
Vol 23 (8) ◽  
pp. 413-419 ◽  
Author(s):  
Cetin Kaymak ◽  
Ela Kadioglu ◽  
Hulya Basar ◽  
Semra Sardas

In this study, genotoxic effects of repeated sevoflurane anaesthesia were investigated in rabbits with or without antioxidant supplementation. Twenty-one New Zealand male rabbits were included in the study and randomized into three groups as: placebo treated (Group I), vitamin E supplemented (Group II) and selenium supplemented (Group III). Vitamin E and selenium were given intraperitoneally for 15 days before anaesthesia treatment. Anaesthesia was administered using 3% sevoflurane in 4 L/min oxygen for a 3-hour period and continued for 3 days. Blood samples were collected before anaesthesia (Sample 1), after the first, second and third days of sevoflurane administration (Sample 2, Sample 3 and Sample 4 respectively) and the last samples were taken 5 days after the last sevoflurane administration (Sample 5). Genotoxic damage was examined using the comet assay. The degree of damage is assessed by grading the cells into three categories of no migration (NM), low migration (LM) and high migration (HM) depending on the fraction of DNA pulled out into the tail under the influence of the electric field. The number of comets in each sample was calculated (1 × number of comets in category NM + 2 × number of comets in category LM + 3 ×number of comets in category HM) and expressed as the total comet score (TCS), which summarizes the damage frequencies. In Group I, a significant increase in the mean TCSs was observed for Samples 3 and 4 as compared with Sample 1. However, there were no significant differences between Samples 1, 2 and 5. The mean TCS of Sample 4 was significantly higher than Sample 1, 2 and 3 in Group II. Group III demonstrated no significant mean TCSs for any experimental conditions. Statistical differences were also observed between the groups with significant P values. This experimental study points out the presence of DNA damage with repeated sevoflurane anaesthesia and the genoprotective role of antioxidant supplementation on DNA damage in mononuclear leukocytes of rabbits by highly sensitive comet assay.


1998 ◽  
Vol 39 (5) ◽  
pp. 538-542 ◽  
Author(s):  
R. Andresen ◽  
S. Radmer ◽  
D. Banzer

Objective: the clinical value of spinal quantitative CT (sQCT) and the structural patterns of the vertebral bone were studied Material and Methods: sQCT was performed on 246 patients with a mean age of 57 years for whom conventional lateral radiographies of the thoracic and lumbar spine were available. All patients were suffering from back pain of unknown etiology. the bone mineral density (BMD) of the midvertebral section of 3 lumbar vertebral bodies was determined by means of single-energy-(SE)-weighted QCT (85 kV). Spongiosa architecture and density profile analyses were made in the axial images. This was contrasted to BMD values ascertained in SE QCT. the mean BMD was compared to the number of fractures and the patients were divided into three groups: group I — no fracture; group II — one fracture; and group III 1 fracture Results: the mean BMD was: 134.3 (74.1–187.5) mg hydroxyapatite (HA)/ml in group I; 79.6 (58.6–114.3) mg HA/ml in group II; and 52.4 (13.1–79.1)mg HA/ml in group III. A significant deterioration in spongiosa structure was found with increasing demineralization: strongly rarefied patterns predominated in the fracture groups II and III Conclusion: sQCT provides a good risk assessment of the occurrence of vertebral body insufficiency fractures


1960 ◽  
Vol 11 (1) ◽  
pp. 75 ◽  
Author(s):  
M Wodzicka

The monthly wool growth of three groups of rams was studied at Beltsville, Maryland. Group I received natural daylight (at 38° 53' N.) and was shorn monthly. Group II had a 7:17 hours of daylight to hours of darkness rhythm and was shorn every 6 months, once in winter and once in summer. Group III received natural daylight and was likewise shorn every 6 months. The rams of all groups produced more wool in summer than in winter. This difference was significant (P<0.001). The mean body weight and food intake were both greater in the winter months, which indicated that the seasonal rhythm of wool growth was not a consequence of poorer feeding in winter. The rams which were shorn monthly (group I) grew considerably more wool than the other two groups, but the difference was not statistically significant. The short-day treatment of group II did not increase the annual wool production nor decrease the seasonal rhythm of wool growth. The balance of evidence from this and other experiments indicates that temperature rather than light controls the seasonal rhythm of wool growth.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
P. López-Jarana ◽  
C. M. Díaz-Castro ◽  
A. Falcão ◽  
C. Falcão ◽  
J. V. Ríos-Santos ◽  
...  

Abstract Background The objective of this study was to measure two parameters involved in tri-dimensional implant planning: the position of the buccal and palatal bone wall and the palatal thickness. Methods Cone beam computed tomography (CBCT) images (Planmeca ProMax 3D) of 403 teeth (208 upper teeth and 195 lower teeth) were obtained from 49 patients referred to the Dental School of Seville from January to December 2014. The height difference between the palatal and buccal walls was measured on the most coronal point of both walls. The thickness of the palatal wall was measured 2 mm from the most coronal point of the palatal wall. Results The mean values in the maxilla were 1.7 ± 0.9 mm for central and lateral incisors, 2.2 ± 1.7 mm for canines, 1.6 ± 0.9 mm for premolars and 1.9 ± 1.5 mm for molars. In the lower jaw, the mean values were 1.3 ± 0.8 mm for incisors, 1.7 ± 1.2 mm for canines, 2.3 ± 1.3 mm for premolars, and 2.6 ± 1.7 mm for molars. In the upper jaw, more than 55% of maxillary teeth (excluding second premolars and molars) presented mean height differences greater than 1 mm. In the mandible, more than 60% of incisors showed a buccal bone thickness of 1 mm from the apical to lingual aspect. All teeth except the second premolar presented a buccal wall located more than 1 mm more apically than the lingual bone wall. Conclusions The buccal bone wall is located more apically (greater than 1 mm) than the palatal or lingual table in most of the cases assessed. The thickness of the palatal or lingual table is also less than 2 mm in the maxilla and mandible, except in the upper canines and premolars and the lower molars.


2021 ◽  
Author(s):  
P.L.E. Oliveira ◽  
C.R. Starling ◽  
C.L.P. Maurício ◽  
F.R. Guedes ◽  
M.A. Visconti ◽  
...  

Introduction: The objective of this study was to compare the mean absorbed dose in patients undergoing head and neck examinations using two cone beam computed tomography (CBCT, Kodak and i-CAT) and one multi-detector computed tomography (MDCT). Methods: Three thermoluminescent dosimeters (TLDs), calibrated in air kerma, were positioned in 24 regions of the head and neck of a phantom simulating an average adult. The mean absorbed dose (mGy) values in these positions, for different organs and tissues, were obtained using correction factors, considering the ratio between the mass energy absorption coefficients of organ/tissue and air. Comparison between radiation doses in the most radiosensitive regions was done by calculating the ratio of these dose values, with propagated uncertainty. Results: The dose in all regions was significantly higher for MDCT when compared to CBCT. Concerning CBCT equipment, the Kodak device had a higher absorbed dose than the i-CAT for most of the regions tested. The uncertainty of the i-CAT was greater than that of the Kodak. Conclusion: Due to the considerable difference between absorbed doses, emphasizing the higher dose values obtained in MDCT, the dissemination of CBCT application in medicine is recommended, as well as further studies to broaden the criteria for use.


2021 ◽  
Vol 7 (2) ◽  
Author(s):  
Atefeh Khavid ◽  
Mojgan Sametzadeh ◽  
Mostafa Godiny ◽  
Mohammad Mehdi Moarrefpour

Background and objective: In recent years, cone-beam computed tomography (CBCT) has become a key diagnostic tool in dentistry. CBCT can provide 3D images of the maxillofacial area to help dental practitioners in diagnosis and treatment, especially implant placement and treatment of pathogenic lesions. This study aimed to compare the Hounsfield Unit (HU) values obtained from CBCT images for bones of different densities with the corresponding HU values from MDCT images. Materials and methods: cube-shaped bone blocks of identical size were cut from the middle section of the cow ribs and femur area such that they had a layer of cortical bone in their buccal, lingual, and top surfaces and trabecular bone in the middle. MDCT scans were performed using a Somatom Sensation Ct Scanner. After determining HU from the results of these scans, nine suitable specimens from different ranges of HU were chosen for comparison. HU of the CBCT images was computed by the dedicated software of the CBCT machine. Finally, HU values obtained from MDCT and CBCT were compared. Data analysis was performed using SPSS version 25 at the 0.05 significance level. Results: The results showed a statistically significant difference between the mean HU from MDCT images and the mean HU from CBCT images (P<0.05). For similar specimens, CBCT produced higher mean HU values than MDCT. The Pearson correlation test detected a significant direct relationship between the HU values of specimens in MDCT and CBCT (P<0.05). Conclusion: For the tools and software used in this study, there was no significant difference between the HU values obtained from MDCT and CBCT, but the mean HU obtained from CBCT was higher than that from MDCT.


2020 ◽  
Vol 47 (2) ◽  
pp. 37-45
Author(s):  
J. O. Okpara ◽  
M. B Abudul ◽  
S. I Garba ◽  
O. V Adelowo ◽  
A. C Mbgojikwe

Interest in medicinal plants for the management of myriad of conditions including reproductive disorders refractory to orthodox medicinal care is on the increase. Ficus syncomorus and Datura metel are two of such plants with folkloric evidence of aiding fertility in human. This study investigated the effect of aqueous stem-bark extracts (200 mg/kg) of F. syncomorus and D. metel respectively on the sperm characteristics of Yankasa rams. Twelve (12) matured (15 – 16 months) old rams were used in this study and randomly assigned into three (I, II, III) groups of four (4) animals each. Group I served as the control while II and III served as the treatment groups and received daily oral doses (200 mg/kg) of F. syncomorus and D. metel extracts respectively for 7 consecutive days. Semen was collected from all the groups at the end of the treatments using Electro-ejaculation method and evaluated by light microscopy. The mean semen volume (68.70+4.2 to 65.62+2.00) and percentage progressive motile cells significantly (p<0.05) reduced 7 days post treatment in group III (84.05+1.3) compared to the control (85.20+1.32) and the group II (86.56+0.40) animals. The mean sperm count, the percentage liveability and the haematological parameters and erythrocytic indices (10.81±0.24 for group 111 to 12.54±0.30 for group1) significantly (p<0.05) decreased in group III compared to the values in the control and group II rams. Abnormal sperm morphology (bent mid-piece, curved tail, headless tail, tailless head) significantly (p<0.05) increased in D. metel group (7.26+0.12) compared to F. syncomorus (5.02+0.04) and control groups (5.62+0.01) respectively. D. metel aquesous extract adversely affected sperm characteristics with significant effect on semen volume, sperm morphology and counts as well as haematological parameters. Exposure of animals to D. metel at the dose used may impair sperm fertilizing ability, thus leading to reduced ram fertility. While F. syncomorus extract appears a potential drug candidate for improving fertility.


Sign in / Sign up

Export Citation Format

Share Document