149 research outputs found
CCD BVRI and 2MASS Photometry of the Poorly Studied Open Cluster NGC 6631
Here we have obtained the {\it BVRI CCD} photometry down to a limiting
magnitude of 20 for the southern poorly studied open cluster NGC 6631.
It is observed from the {\it 1.88 m} Telescope of Kottamia Observatory in
Egypt. About 3300 stars have been observed in an area of around the cluster center. The main photometric parameters
have been estimated and compared with the results that determined for the
cluster using {\it JHKs 2MASS} photometric database. The cluster's diameter is
estimated to be 10 arcmin; the reddening E(B-V)= 0.68 0.10 mag, E(J-H)=
0.21 0.10 mag, the true modulus (m-M)= 12.16 0.10 mag, which
corresponds to a distance of 2700 125 pc and age of 500 50 Myr.Comment: 13 pages, 6 figure
EFFECTIVENESS OF PLATELET- RICH FIBRIN WITH BETA TRI-CALCIUM PHOSPHATE PLUS CALCIUM SULFATE ON PERIODONTAL INTRABONY DEFECT MANAGEMENT (RANDOMIZED CONTROLLED CLINICAL STUDY)
The purpose of this study is to evaluate the effectiveness of beta tri-calcium phosphate plus calcium sulfate mix, with or without platelet rich fibrin in reducing probing periodontal pockets clinically and defect depths radiographically, while increasing clinical attachment levels to reconstruct intrabony defects in human clinical trials. Materials and Methods: Sixteen participants with periodontal intrabony defects ≥ 5 mm were divided into two equal groups. The first eight intrabony defects in study group received platelet rich fibrin mixed with EthOss ®; while the eight remaining intrabony defects in control group were reconstructed only with EthOss® synthetic bone substitute. Freidman ANOVA and Mann-Whitney tests were chosen for intra-group and inter-group comparisons, respectively. Results: Final outcomes revealed statistically significant decrease in periodontal pocket depth and defect depth values (P ˂ 0.05) with a statistically significant clinical attachment level gain in study and control groups. Precisely, mean values of all measured categories were greater in study rather than control group participants, as confirmed clinically by William’s probe and radiographically by cone-beam computed tomography at 6 months after surgery. Conclusion: Adding PRF to β-TCP plus CS is highly effective in inducing new periodontal soft and hard tissue synthesis resulting in better clinical and radiographic outcomes when surgically incorporated in periodontal intrabony defect(s)
Editorial Guest
“We are what we repeatedly do. Excellence, therefore, is not an act, but a habit.” Aristotl
USING CONE-BEAM COMPUTED TOMOGRAPHY TO EVALUATE APICAL TRANSPORTATION AND CENTERING ABILITY OF WAVEONE, ONESHAPE AND TORNADO ROTARY SYSTEMS: A CLINICAL STUDY
This clinical study was aimed to evaluate apical transportation and centering ability of WaveOne, OneShape files and Tornado rotary system using Cone-beam computed tomography (CBCT). Lower molars with a curving angle of buccal canals extending from 15°-45° in 24 patients were arbitrarily divided into three groups (n=8) rendering to the rotary systems used: Group 1, Tornado system, Group 2, WaveOne rotary system, and Group 3, OneShape rotary system. CBCT was used as a diagnostic method to evaluate centering ratio and canal transportation at 2, 5 and 8 mm from apical foramen. One-way analysis of variance and post hoc Tukey tests were used for statistical analysis at p≤0.05. No statistically significant difference in the magnitude of transportation and centering ability was found at all tested levels (P\u3e0.05). WaveOne and OneShape nickel-titanium files and Tornado stainless-steel file conserved the original canal curvature with no significant variance
Evaluation of Guided Bone Regeneration Using Xenograft/APRF Mixture in Atrophic Posterior Mandible (Clinical and Radiographic study)
Introduction: The rehabilitation of posterior mandible with dental implants represents today a hard challenge for clinicians due to the lack of supporting bone. Different surgical techniques are currently being used to augment the posterior mandible where GBR is considered most commonly used. Materials and Methods: Fifteen patients were selected to treat mandibular alveolar ridge resorption with guided bone regeneration using titanium reinforced membrane and a filling mixture of xenograft bovine bone/PRF. The membrane was fixed using meisinger pin control kit and profix 3mm microscrews. A PRF membrane was used to cover the Ti d-ptfe. Results: Using the mixture of PRF/xenograft as well as PRF membranes showed promising results in term of primary wound healing, whereas a significant bone quantity with a mean bone volume of 5.78 ± 0.81 was reported. The primary implant stability recorded high values and significantly increased at a period of 6 months post insertion p=0.037 Conclusion: It could be concluded that PFR/ xenograft mixture can be promising when used with the titanium reinforced d-ptfe membrane in 3D ridge reconstruction of atrophic posterior mandible, moreover using PRF membrane to cover the TI- d-ptfe membrane could enhance soft tissue healing as well as it can prevent soft tissue dehiscence due to the concentration of the growth factors that can be released during primary wound healing. Xenograft/PRf mixture can be consistent to be utilized for creation of new bone in severely atrophic ridges if used in GBR. The high ISQ at primary implant placement and at a period of 6 months post insertion according to Osstell can explain the successful application of this mixture in 3D bone augmentation of atrophic posterior mandible
Evaluation of Guided Bone Regeneration Using Xenograft/APRF Mixture in Atrophic Posterior Mandible (Clinical and Radiographic Study)
Introduction: The rehabilitation of the posterior mandible with dental implants represents a hard challenge for clinicians today due to the lack of supporting bone. Different surgical techniques are currently being used to augment the posterior mandible, where GBR is considered the most commonly used. Materials and Methods: Fifteen patients were selected to treat mandibular alveolar ridge resorption with guided bone regeneration using a titanium-reinforced membrane and a filling mixture of xenograft bovine bone and PRF. The membrane was fixed using a Meisinger pin control kit and Profix 3mm microscrews. A PRF membrane was used to cover the Ti-d-ptfe.
Results: Swelling, pain, and numbness were evaluated using the mixture of PRF/xenograft as well as PRF membranes. The results showed promising results in terms of primary wound healing, whereas a significant bone quantity with a mean bone volume of 5.78 ± 0.81 was reported after 6 months. The primary implant stability recorded high values and significantly increased at a period of 6 months post-insertion (p = 0.037). Conclusion: It could be concluded that the PFR/xenograft mixture can be promising when used with the titanium-reinforced d-ptfe membrane in 3D ridge reconstruction of the atrophic posterior mandible; moreover, using the PRF membrane to cover the TI-d-ptfe membrane could enhance soft tissue healing as well as prevent soft tissue dehiscence due to the concentration of growth factors that can be released during primary wound healing. The xenograft/PRf mixture can be consistently utilized for the creation of new bone in severely atrophic ridges if used in GBR. The high ISQ at primary implant placement and at a period of 6 months post-insertion, according to Osstell, can explain the successful application of this mixture in 3D bone augmentation of the atrophic posterior mandible
Evaluation of Guided Bone Regeneration Using Xenograft/APRF Mixture in Atrophic Posterior Mandible (Clinical and Radiographic study)
Introduction: The rehabilitation of posterior mandible with dental implants represents today a hard challenge for clinicians due to the lack of supporting bone. Different surgical techniques are currently being used to augment the posterior mandible where GBR is considered most commonly used. Materials and Methods: Fifteen patients were selected to treat mandibular alveolar ridge resorption with guided bone regeneration using titanium reinforced membrane and a filling mixture of xenograft bovine bone/PRF. The membrane was fixed using meisinger pin control kit and profix 3mm microscrews. A PRF membrane was used to cover the Ti d-ptfe. Results: Using the mixture of PRF/xenograft as well as PRF membranes showed promising results in term of primary wound healing, whereas a significant bone quantity with a mean bone volume of 5.78 ± 0.81 was reported. The primary implant stability recorded high values and significantly increased at a period of 6 months post insertion p=0.037 Conclusion: It could be concluded that PFR/ xenograft mixture can be promising when used with the titanium reinforced d-ptfe membrane in 3D ridge reconstruction of atrophic posterior mandible, moreover using PRF membrane to cover the TI- d-ptfe membrane could enhance soft tissue healing as well as it can prevent soft tissue dehiscence due to the concentration of the growth factors that can be released during primary wound healing. Xenograft/PRf mixture can be consistent to be utilized for creation of new bone in severely atrophic ridges if used in GBR. The high ISQ at primary implant placement and at a period of 6 months post insertion according to Osstell can explain the successful application of this mixture in 3D bone augmentation of atrophic posterior mandible
EFFECT OF DIFFERENT IRRIGATION REGIMENS ON ENTEROCOCCUS FAECALIS ELIMINATION FROM INFECTED ROOT CANALS (AN IN-VITRO COMPARATIVE STUDY)
Microorganisms harbored in the complexities of root canal systems might lead to endodontic failures and development of apical periodontitis. Enterococcus faecalis is the most common isolated bacteria in these cases. Aim: This study was conducted to compare the efficiency of four irrigation regimens on the elimination of an inoculated strain of E. faecalis. Materials and Methods: Forty single rooted extracted premolars were inoculated with a standard strain of Enterococcus faecalis (ATCC 29212) and incubated at 37˚C for two weeks to allow infection of the dentinal tubules. The bacterial suspension was replaced with a new one every 48 hours. The teeth were then divided into four groups of n=10 each, to apply irrigation regimens as follows: Group i: irrigation with normal saline, Group ii: syringe irrigation (NaOCl 2.625%), Group iii: NaOCl 2.625%+EndoActivator and Group iv: NaOCl 2.625%+diode laser. Samples were collected at baseline and after irrigation. Colony-forming unit counts were performed. For baseline count of E. faecalis, differences in means between the groups were tested using the one way ANOVA F test. For the count of E. faecalis after the irrigation, differences in means was assessed using the Kruskal Wallis test. Results: The mean values of % of E. faecalis killed were respectively 99.2 ± 2.53% in group iv, 98.3± 5.34% in group iii, 29.0 ± 5.46% in group ii and 4.77 ± 0.78%) in group i. Conclusion: Maximum removal of E. faecalis strains was achieved by activating 2.625% sodium hypochlorite with the diode laser
A COMPARISON BETWEEN THE EFFECT OF DIFFERENT PRESSURES OF AIR PARTICLE ABRASION BEFORE AND AFTER SINTERING WITH AND WITHOUT ZIRCONIA LINER ON BOND STRENGTH OF RESIN TO ZIRCONIA SURFACE
This study aimed to compare the effect of different pressures of air particle abrasion 2 and 4 bars before and after sintering with and without zirconia liner on SBS of resin to zirconia Surface. Materials and Methods: 54 zirconia cuboids 8×8×3 mm were milled and divided into 6 equal groups (N=9) according to surface treatment; sintered with ceramic liner application and 2 bars pressure (SL2) and with 4 bars pressure (SL4), sintered with no ceramic liner and 2 bars pressure (SN2) and 4 bars pressure (SN4), unsintered with no ceramic liner and 2 bars pressure (UN2) and 4 bars pressure (UN4). Specimens underwent thermocycling (1000 cycles) between 5 ̊ and 55 ̊ Celsius with dwell time of 10 seconds, and submitted to SBS test. Data was statistically analysed. Results: All 4 bars APA groups showed higher SBS than 2 bars groups with significant difference between SL4 group (4.7±2.07) and SL2 group (2.58±1.94). Groups with APA before sintering (12.42±2.56) showed significantly higher SBS than APA after sintering (6.35±3.7). SL2 group showed least SBS with significant difference (2.58±1.94) compared to UN2 (11.83±3.35) and SN2 (7.87±2.12). SL4 group (4.7±2.07) showed the least SBS compared to the UN4 (13±1.38), and SN4 (10.24±2.94) groups. Conclusion: It was found that APA of zirconia surface before sintering yielded superior performance than APA after sintering, also 4 bars APA pressure application showed higher SBS than 2 bars pressure, application and firing of ceramic liner onto zirconia surface didn’t enhance SBS
Bilateral acute angle closure glaucoma after hyperopic LASIK correction
AbstractAcute angle closure glaucoma is unexpected complication following laser in situ keratomileusis (LASIK). We are reporting a 49-years-old lady that was presented to the emergency department with acute glaucoma in both eyes soon after LASIK correction. Diagnosis was made on detailed clinical history and examination, slit lamp examination, intraocular pressure measurement and gonioscopy. Laser iridotomy in both eyes succeeded in controlling the attack and normalizing the intraocular pressure (IOP) more than 6months of follow-up. Prophylactic laser iridotomy is essential for narrow angle patients before LASIK surgery if refractive laser surgery is indicated
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