Current Issue : January - March Volume : 2014 Issue Number : 1 Articles : 5 Articles
Background: Zirconia materials are known for their optimal aesthetics, but they are\r\nbrittle, and concerns remain about whether their mechanical properties are sufficient\r\nfor withstanding the forces exerted in the oral cavity. Therefore, this study compared\r\nthe maximum deformation and failure forces of titanium implants between titaniumalloy\r\nand zirconia abutments under oblique compressive forces in the presence of\r\ntwo levels of marginal bone loss.\r\nMethods: Twenty implants were divided into Groups A and B, with simulated bone\r\nlosses of 3.0 and 1.5 mm, respectively. Groups A and B were also each divided into\r\ntwo subgroups with five implants each: (1) titanium implants connected to titaniumalloy\r\nabutments and (2) titanium implants connected to zirconia abutments. The\r\nmaximum deformation and failure forces of each sample was determined using a\r\nuniversal testing machine. The data were analyzed using the nonparametric\r\nMannââ?¬â??Whitney test.\r\nResults: The mean maximum deformation and failure forces obtained the subgroups\r\nwere as follows: A1 (simulated bone loss of 3.0 mm, titanium-alloy abutment) =\r\n540.6 N and 656.9 N, respectively; A2 (simulated bone loss of 3.0 mm, zirconia\r\nabutment) = 531.8 N and 852.7 N; B1 (simulated bone loss of 1.5 mm, titaniumalloy\r\nabutment) = 1070.9 N and 1260.2 N; and B2 (simulated bone loss of 1.5 mm,\r\nzirconia abutment) = 907.3 N and 1182.8 N. The maximum deformation force differed\r\nsignificantly between Groups B1 and B2 but not between Groups A1 and A2. The\r\nfailure force did not differ between Groups A1 and A2 or between Groups B1 and\r\nB2. The maximum deformation and failure forces differed significantly between\r\nGroups A1 and B1 and between Groups A2 and B2.\r\nConclusions: Based on this experimental study, the maximum deformation and\r\nfailure forces are lower for implants with a marginal bone loss of 3.0 mm than of\r\n1.5 mm. Zirconia abutments can withstand physiological occlusal forces applied in\r\nthe anterior region....
To report the clinical outcome of high dose rate brachytherapy as sole treatment for clinically\r\nlocalised prostate cancer.\r\nMethods: Between March 2004 and January 2008, a total of 351 consecutive patients with clinically localised\r\nprostate cancer were treated with transrectal ultrasound guided high dose rate brachytherapy. The prescribed dose\r\nwas 38.0 Gy in four fractions (two implants of two fractions each of 9.5 Gy with an interval of 14 days between the\r\nimplants) delivered to an intraoperative transrectal ultrasound real-time defined planning treatment volume.\r\nBiochemical failure was defined according to the Phoenix Consensus and toxicity evaluated using the Common\r\nToxicity Criteria for Adverse Events version 3.\r\nResults: The median follow-up time was 59.3 months. The 36 and 60 month biochemical control and metastasisfree\r\nsurvival rates were respectively 98%, 94% and 99%, 98%. Toxicity was scored per event with 4.8% acute Grade 3\r\ngenitourinary and no acute Grade 3 gastrointestinal toxicity. Late Grade 3 genitourinary and gastrointestinal toxicity\r\nwere respectively 3.4% and 1.4%. No instances of Grade 4 or greater acute or late adverse events were reported.\r\nConclusions: Our results confirm high dose rate brachytherapy as safe and effective monotherapy for clinically\r\norgan-confined prostate cancer....
Introduction: Aim of the study was to assess the impact of the length of mini-implants inserted in the midpalatal\r\nregion on the stability at the initial healing period.\r\nMethods: A sample of 20 consecutively treated patients (15.6 �± 7.2 years) was examined. A long mini-implant with a\r\nlength of 11 mm and a diameter of 2 mm was inserted into the anterior palate of each patient. Resonance frequency\r\nanalysis (RFA) was performed after insertion (T0), two weeks (T1), four weeks (T2), and six weeks (T3). Insertion depth\r\n(ID) and the maximum insertion torque (IT) were measured. RFA, ID and IT data were tested for correlations. RFA\r\nvalues were tested for statistical differences between the different times. Data was compared to a matched control\r\ngroup of patients who received short mini-implants with a length of 9 mm and a diameter of 2 mm.\r\nResults: Mean ID was 9.5 �± 0.6 mm and mean IT was 17.9 �± 3.8 Ncm. A correlation was found between RFA and ID\r\n(r = 0.59, P < .01). From T0 to T1 the stability (33.4 �± 3.5 ISQ) decreased highly significantly by 5.3 �± 3.5 ISQ values\r\n(P < .001) and significantly from T1 and T2 (P < .05) by 3.5 �± 3.7 ISQ values. From T2 on RFA nearly remained\r\nunchanged (-1.7 �± 3.9 ISQ; P > .05). At T1 stability was significantly lower than the control group. From T2 on there\r\nwere no significant differences between the groups.\r\nConclusions: Long mini-implants provide high stability when inserted in the midpalatal region. After initial decrease\r\nRFA values remained stable from four weeks on and did not differ from the control group....
Background: Proliferative vitreoretinopathy (PVR) is the commonest cause of late anatomical failure in rhegmatogenous\r\nretinal detachment. Visual and anatomical outcomes remain poor despite advances in vitreoretinal surgical techniques\r\nwith reported primary failure rates of up to nearly 50%. Numerous adjunctive medications have been evaluated in\r\nclinical trials with no agent gaining widespread acceptance and use.\r\nThis study was designed to investigate the benefits of using a slow-release dexamethasone implant delivered\r\nintra-operatively in patients undergoing vitrectomy surgery for retinal detachment with established PVR.\r\nMethods/design: For the study, 140 patients requiring vitrectomy surgery with silicone oil for retinal detachment\r\nwith established PVR will be randomised to receive either standard treatment or study treatment in a 1:1 treatment\r\nallocation ratio. Both groups will receive the standard surgical treatment appropriate for their eye condition and routine\r\nperi-operative treatment and care, differing only in the addition of the supplementary adjunctive agent in the\r\ntreatment group. The investigated primary outcome measure is stable retinal reattachment with removal of silicone\r\noil without additional vitreoretinal surgical intervention at 6 months.\r\nDiscussion: This is the first randomised controlled clinical trial to investigate the use of an adjunctive slow-release\r\ndexamethasone implant in patients undergoing vitrectomy surgery for retinal detachments with proliferative\r\nvitreoretinopathy....
Background: The aim of the study was to examine the reactivity of peripheral human leukocytes to various metal\r\nions prior and following hip replacement in order to investigate implant-induced metal sensitivity.\r\nMethods: Three patient groups were set up: (1) individuals without implants and no history of metal allergy (7 cases),\r\n(2) individuals without implants and known history of metal allergy (7 cases), and (3) patients undergoing cementless\r\nhip replacement (40 cases). Blood samples were taken in groups 1 and 2 at three different occasions; in group 3, prior\r\nand 3, 6, 12, 24, and 36 months after surgery. Peripheral leukocytes were separated and left either untreated or\r\nchallenged with Ti, NiCl2, CoCl2, CrCl3, and phytohemagglutinin. Cell proliferation, cytokine release, and leukocyte\r\nmigration inhibition assays were performed. Metal-induced reactivity was considered when all three assays showed\r\nsignificant change. Skin patch tests were also carried out.\r\nResults: Both skin patch tests and leukocyte functional tests were negative in group 1, and both were positive in\r\ngroup 2. In group 3, after 6 months, 12% of the patients showed reactivity to the tested metals except for NiCl2.\r\nFollowing the 36-month period, 18% of group three became sensitive to metals (including all the earlier 12%). In\r\ncontrast, patch tests were negative at each time point in group 3.\r\nConclusions: Orthopedic implant material may induce metal reactivity after implantation in a manner where\r\nsusceptibility is yet to be elucidated. Leukocyte triple assay technique might be a useful tool to test implant materialrelated\r\nsensitivity....
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