scholarly journals Effect of Splinting in Accuracy of Two Implant Impression Techniques

2014 ◽  
Vol 40 (6) ◽  
pp. 633-639 ◽  
Author(s):  
Erica Dorigatti de Avila ◽  
Fernanda de Matos Moraes ◽  
Sabrina Maria Castanharo ◽  
Marcelo Antonialli Del'Acqua ◽  
Francisco de Assis Mollo

Because there is no consensus in the literature about the need for a splint between copings, the aim of this study was to evaluate, in vitro, the accuracy of 2 impression techniques for implant-supported prostheses. A master cast was fabricated with four parallel implant abutment analogs and a passive framework. Two groups with 5 casts each were formed: Group 1 (squared impression copings with no splint: S) and Group 2 (splinted squared impression copings, using metal drill burs and Pattern resin: SS). The impression material used was polyvinyl siloxane with open trays for standard preparation of the casts. For each cast, the framework was positioned, and a titanium screw was tightened with 10 N·cm torque in analog A, after which measurements of the abutment-framework interface gaps were performed at analogs C and D. This process was repeated for analog D. These measurements were analyzed using software. A one-way analysis of variance (ANOVA) with a confidence interval of 95% was used to analyze the data. Significant differences were detected between S and SS in relation to the master cast (P ≤ 0.05). The median values of the abutment-framework interface gaps were as follows: master cast: 39.64 μm; squared impression copings with no splint: 205.86 μm; splinted squared impression copings: 99.19 μm. Under the limitations of this study, the technique presented for Group 2 produces better results compared with the technique used for Group 1.

2014 ◽  
Vol 40 (1) ◽  
pp. 30-34 ◽  
Author(s):  
Simonetta D'Ercole ◽  
Antonio Scarano ◽  
Vittoria Perrotti ◽  
Jorge Mulatinho ◽  
Adriano Piattelli ◽  
...  

Prevention of microbial leakage at the implant-abutment junction is a major challenge for the construction of 2-stage implants in order to minimize inflammatory reactions and to maximize bone stability at the implant neck. The aim of the present in vitro study was an evaluation of the leakage observed over a period of 28 days in Cone Morse taper internal connections and in screwed-abutments connections. In the present study 10 specimens of Cone Morse (Group 1) and 10 of internal hexagon (Group 2) implants were used. The inner parts of 5 implants per group were inoculated with Pseudomonas aeruginosa (PS) suspension and 5 implants per group with Aggregatibacter actinomycetemcomitans (AA). The possible penetration of bacterial suspension into the surrounding solution was determined by the observation of turbidity of the broth. In Group 1, bacterial contamination was found in 3 out of 5 implant-abutment assemblies seeded with the PS and in 2 samples out of 5 in the assemblies seeded with AA, with a total of leaked assemblies in this group of 5 out of 10. In Group 2, bacterial contamination was found in 4 out of 5 implant-abutment assemblies seeded with the PS, and in 4 out of 5 samples seeded with AA, with a total of leaked assemblies of 8 out of 10. The present data confirm the reported high permeability to bacterial leakage of screw-retained abutment connections, and the lower infiltration rates—although not significantly—of Cone Morse taper internal connections.


2014 ◽  
Vol 25 (1) ◽  
pp. 48-53 ◽  
Author(s):  
Deceles Cristina Costa Alves ◽  
Paulo Sérgio Perri de Carvalho ◽  
Elizabeth Ferreira Martinez

The objective of this study was to evaluate the bacterial seal at the implant-abutment interface using two morse taper implant models, by means of an in vitro microbiological analysis. For that were used 15 implants with mini-abutments tightened by friction, no screws (Group 1); and 30 implants with screw-tightened abutments, of which 15 received 20 N.cm of closing torque (Group 2) and the other 15 received 30 N.cm (Group 3). Microbiological analysis was carried out using colonies of Escherichia coli transported directly from a culture dish to the prosthetic component. Friction implants (Group 1) were activated by tapping and a torque wrench was used for screw-tightened implants (Groups 2 and 3). Each abutment/implant set was immersed in test tubes containing 5 mL of brain-heart infusion broth and incubated at 37 °C for 14 days, observed daily for the presence of contamination. A statistically significant difference was observed regarding the number of contaminated implants. There was greater contamination in Group 2 implants (p<0.05), with no statistically significant difference between the other groups (Group 1 = 20% and Group 3 = 0%). It was concluded that there was no significant difference in in vitro bacterial sealing between implants with mini-abutments tightened by friction without screws and implants with screw-tightened abutments with 30 N.cm of closing torque. The difference in closing torque altered the in vitro sealing ability of the tested abutments, with a greater contamination for components that received a closing torque of 20 N.cm.


2021 ◽  
Vol 7 (6) ◽  
pp. 57552-57565
Author(s):  
Thamiris Nogueira Sacker ◽  
Micheline Sandini Trentin ◽  
Thais Maria Pires dos Santos ◽  
Ricardo Tadeu Lopes ◽  
Elken Gomes Rivaldo

Objectives: To evaluate in vitro the micromorphological differences of the prosthetic implant-abutment interface in two screw implant systems and a friction one.Materials and methods: Two screw implants (Group 1- Crossfit Internal Connection, Group 2- Tapered Internal Connection), a compressed friction implant (Group 3 - Frictional Connection), and their corresponding prosthetic components were used. The implants were individually fixed in an acrylic resin cylinder and the abutments were positioned with the torque recommended by the manufacturer and taken into a SkyScan 1173 microtomograph. In each implant-abutment image, the regions of interest evaluated were cervical area, abutment area, screw area, and abutment and screw area (G1-G2). In group 3, the cervical and abutment areas were measured. Statistical analysis was performed with ANOVA, Robust ANOVA, and Post Hoc Tukey’s test.Results: In the cervical region, only the samples from group 2 presented maladaptation (12.5 ± 7.0 µm). In the abutment area, the samples from groups 1 (159.6 ± 6.2 µm) and 2 (149.9 ± 9.1 µm) were statistically similar. In the screw area and the abutment and screw area, group 1 had a larger contact surface compared to group 2 but they were statistically similar.Conclusion: The samples from groups 1 and 3 did not present micro-spaces in the cervical third. Nevertheless, the samples from group 2 presented a mismatch in this region but within the acceptable limits found in the literature.


2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Gayem İnayet Turgay Çelik ◽  
Havva Kömür Sütçü ◽  
Yaşam Kemal Akpak ◽  
Münire Erman Akar

Objective. To compare the effectiveness of a flexible multidose gonadotropin-releasing hormone (GnRH) antagonist against the effectiveness of a microdose flare-up GnRH agonist combined with a flexible multidose GnRH antagonist protocol in poor responders to in vitro fertilization (IVF).Study Design. A retrospective study in Akdeniz University, Faculty of Medicine, Department of Obstetrics and Gynecology, IVF Center, for 131 poor responders in the intracytoplasmic sperm injection-embryo transfer (ICSI-ET) program between January 2006 and November 2012. The groups were compared to the patients’ characteristics, controlled ovarian stimulation (COH) results, and laboratory results.Results. Combination protocol was applied to 46 patients (group 1), and a single protocol was applied to 85 patients (group 2). In group 1, the duration of the treatment was longer and the dose of FSH was higher. The cycle cancellation rate was significantly higher in group 2 (26.1% versus 38.8%). A significant difference was not observed with respect to the number and quality of oocytes and embryos or to the number of embryos transferred. There were no statistically significant differences in the hCG positivity (9.5% versus 9.4%) or the clinical pregnancy rates (7.1% versus 10.6%).Conclusion. The combination protocol does not provide additional efficacy.


2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 340.2-341
Author(s):  
V. Orefice ◽  
F. Ceccarelli ◽  
C. Barbati ◽  
R. Lucchetti ◽  
G. Olivieri ◽  
...  

Background:Systemic lupus erythematosus (SLE) is an autoimmune disease mainly affecting women of childbearing age. The interplay between genetic and environmental factors may contribute to disease pathogenesis1. At today, no robust data are available about the possible contribute of diet in SLE. Caffeine, one of the most widely consumed products in the world, seems to interact with multiple components of the immune system by acting as a non-specific phosphodiesterase inhibitor2.In vitrodose-dependent treatment with caffeine seems to down-regulate mRNA levels of key inflammation-related genes and similarly reduce levels of different pro-inflammatory cytokines3.Objectives:We evaluated the impact of caffeine consumption on SLE-related disease phenotype and activity, in terms of clinimetric assessment and cytokines levels.Methods:We performed a cross-sectional study, enrolling consecutive patients and reporting their clinical and laboratory data. Disease activity was assessed by SLE Disease Activity Index 2000 (SLEDAI-2k)4. Caffeine intake was evaluated by a 7-day food frequency questionnaire, including all the main sources of caffeine. As previously reported, patients were divided in four groups according to the daily caffeine intake: <29.1 mg/day (group 1), 29.2-153.7 mg/day (group 2), 153.8-376.5 mg/day (group 3) and >376.6 mg/day (group 4)5. At the end of questionnaire filling, blood samples were collected from each patient to assess cytokines levels. These were assessed by using a panel by Bio-Plex assays to measure the levels of IL-6, IL-10, IL-17, IL-27, IFN-γ, IFN-α and Blys.Results:We enrolled 89 SLE patients (F/M 87/2, median age 46 years, IQR 14; median disease duration 144 months, IQR 150). The median intake of caffeine was 195 mg/day (IQR 160.5). At the time of the enrollment, 8 patients (8.9%) referred a caffeine intake < 29.1 mg/day (group 1), 27 patients (30.3%) between 29.2 and 153.7 mg/day (group 2), 45 patients (51%) between 153.8 and 376.5 mg/day (group 3) and 9 patients (10.1%) >376.6 mg/day (group 4). A negative correlation between the levels of caffeine and disease activity, evaluated with SLEDAI-2K, was observed (p=0.01, r=-0.26). By comparing the four groups, a significant higher prevalence of lupus nephritis, neuropsychiatric involvement, haematological manifestations, hypocomplementemia and anti-dsDNA positivity was observed in patients with less intake of caffeine (figure 1 A-E). Furthermore, patients with less intake of caffeine showed a significant more frequent use of glucocorticoids [group 4: 22.2%,versusgroup 1 (50.0%, p=0.0001), group 2 (55.5%, p=0.0001), group 3 (40.0%, p=0.009)]. Moving on cytokines analysis, a negative correlation between daily caffeine consumption and serum level of IFNγ was found (p=0.03, r=-0.2) (figure 2A); furthermore, patients with more caffeine intake showed significant lower levels of IFNα (p=0.02, figure 2B), IL-17 (p=0.01, figure 2C) and IL-6 (p=0.003, figure 2D).Conclusion:This is the first report demonstrating the impact of caffeine on SLE disease activity status, as demonstrated by the inverse correlation between its intake and both SLEDAI-2k values and cytokines levels. Moreover, in our cohort, patients with less caffeine consumption seems to have a more severe disease phenotype, especially in terms of renal and neuropsychiatric involvement. Our results seem to suggest a possible immunoregulatory dose-dependent effect of caffeine, through the modulation of serum cytokine levels, as already suggested byin vitroanalysis.References:[1]Kaul et alNat. Rev. Dis. Prim.2016; 2. Aronsen et alEurop Joul of Pharm2014; 3. Iris et alClin Immun.2018; 4. Gladman et al J Rheumatol. 2002; 5. Mikuls et alArth Rheum2002Disclosure of Interests:Valeria Orefice: None declared, Fulvia Ceccarelli: None declared, cristiana barbati: None declared, Ramona Lucchetti: None declared, Giulio Olivieri: None declared, enrica cipriano: None declared, Francesco Natalucci: None declared, Carlo Perricone: None declared, Francesca Romana Spinelli Grant/research support from: Pfizer, Consultant of: Novartis, Gilead, Lilly, Sanofi, Celgene, Speakers bureau: Lilly, cristiano alessandri Grant/research support from: Pfizer, Guido Valesini: None declared, Fabrizio Conti Speakers bureau: BMS, Lilly, Abbvie, Pfizer, Sanofi


Author(s):  
Tsuyoshi Yamabe ◽  
Yanling Zhao ◽  
Paul A Kurlansky ◽  
Suzuka Nitta ◽  
Saveliy Kelebeyev ◽  
...  

Abstract OBJECTIVES Chronic kidney disease (CKD) is prevalent in patients undergoing cardiovascular surgery, and it negatively impacts procedural outcomes; however, its influence on the outcomes of aortic surgery has not been well studied. This study aims to elucidate the importance of CKD on the outcomes of aortic root replacement (ARR). METHODS Patients who underwent ARR between 2005 and 2019 were retrospectively reviewed (n = 882). Patients were divided into 3 groups based on the Kidney Disease: Improving Global Outcomes criteria: Group 1 [estimated glomerular filtration rate (eGFR) ≥ 60 ml/min/1.73 m2, n = 421); Group 2 (eGFR = 30–59 ml/min/1.73 m2, n = 424); and Group 3 (eGFR &lt; 30 ml/min/1.73 m2, n = 37). To reduce potential confounding, a propensity score matching was also performed between Group 1 and the combined group of Group 2 and Group 3. The primary end point was 10-year survival. Secondary end points were in-hospital mortality and perioperative morbidity. RESULTS Severe CKD patients presented with more advanced overall chronic and acute illnesses. Kaplan–Meier analysis showed a significant correlation between CKD stage and 10-year survival (log-rank P &lt; 0.001). The number of events for Group 1 was 15, Group 2 was 49 and Group 3 was 11 in 10 years. Group 3 had significantly higher in-hospital mortality (13.5% vs 3.5% in Group 2 vs 0.7% in Group 1, P &lt; 0.001) and stroke (8.1% vs 7.1% vs 1.2%, P &lt; 0.001) as well as introduction to new dialysis (27.0% vs 5.4% vs 1.7%, P &lt; 0.001). eGFR was shown to be an independent predictor of mortality (hazard ratio, 0.98; 95% confidence interval, 0.96–0.99). Comparison between propensity matched groups showed similar postoperative outcomes, and eGFR was still identified as a predictor of mortality (hazard ratio, 0.97; 95% confidence interval, 0.95–0.99). CONCLUSIONS Higher stage in CKD negatively impacts the long-term survival in patients who are undergoing ARR.


Scientifica ◽  
2015 ◽  
Vol 2015 ◽  
pp. 1-6
Author(s):  
Vedavathi Bore Gowda ◽  
B. V. Sreenivasa Murthy ◽  
Swaroop Hegde ◽  
Swapna Devarasanahalli Venkataramanaswamy ◽  
Veena Suresh Pai ◽  
...  

Aim. To compare the microleakage in class II composite restorations without a liner/with resin modified glass ionomer and flowable composite liner.Method. Forty standardized MO cavities were prepared on human permanent mandibular molars extracted for periodontal reasons and then divided into 4 groups of ten specimens. The cavity preparations were etched, rinsed, blot dried, and light cured and Adper Single Bond 2 is applied. Group 1 is restored with Filtek P60 packable composite in 2 mm oblique increments. Group 2 is precure group where 1 mm Filtek Z350 flowable liner is applied and light cured for 20 sec. Group 3 is the same as Group 2, but the liner was cocured with packable composite. In Group 4, 1 mm RMGIC, Fuji Lining LC is applied and cured for 20 sec. All the teeth were restored as in Group 1. The specimens were coated with nail varnish leaving 1 mm around the restoration, subjected to thermocycling, basic fuchsin dye penetration, sectioned mesiodistally, and observed under a stereomicroscope.Results. The mean leakage scores of the individual study groups were Group 1 (33.40), Group 2 (7.85), Group 3 (16.40), and Group 4 (24.35). Group 1 without a liner showed maximum leakage. Flowable composite liner precured was the best.


1994 ◽  
Vol 6 (2) ◽  
pp. 207-215 ◽  
Author(s):  
Bradd C. Barr ◽  
Joan D. Rowe ◽  
Karen W. Sverlow ◽  
Robert H. BonDurant ◽  
Alex A. Ardans ◽  
...  

Studies were conducted to determine the pathogenic potential of the recently isolated bovine Neospora protozoa (BPA-1) for the bovine fetus. Cows chosen for study had Neospora titers < 160 using an indirect immunofluorescent antibody (IFA) test. Four experimental groups were studied. In group 1, 2 fetuses were inoculated in utero at 118 days gestation with culture-derived Neospora tachyzoites. A pregnant control cow was housed in the same pen, observed daily and screened serologically for evidence of exposure to Neospora. In group 2, 2 cows were infected with Neospora tachyzoites at 138 or 161 days gestation, and 1 control cow was given uninfected cell culture suspension simultaneously at 154 days gestation. Groups 3 (85 days gestation) and 4 (120 days gestation) each consisted of 2 cows infected with Neospora tachyzoites and 1 control cow given uninfected material at the same stage of gestation. Dead fetuses were surgically removed from the infected cows in group 1 on postinfection day (PID) 17. The histopathology was compatible with protozoal fetal infection, and protozoa were identified by immunohistochemistry. Viable fetuses were removed surgically from cows in group 2 on PID 28-30. The histopathology was compatible with protozoal fetal infection, protozoa were identified by immunoperoxidase techniques, and Neospora tachyzoites were reisolated in vitro from tissues of the 2 infected fetuses. In groups 3 and 4, the control fetus and 1 infected fetus were removed surgically between PID 26 and PID 33. The remaining infected cows were observed until fetal death or abortion occurred. In group 3, the fetus that was surgically removed from 1 infected cow had no pathologic abnormalities, and parasites were not found (PID 26). The second fetus in group 3 died in utero, and expulsion of a mummified fetus was induced on PID 67. Brain histopathology was compatible with protozoal infection, and parasites were identified by immunoperoxidase techniques. The fetus that was surgically removed (PID 32) from 1 infected cow in group 4 had lesions compatible with protozoal infection, and Neospora tachyzoites were reisolated in vitro from fetal tissues. The second infected cow in group 4 produced a full-term live calf that had a precolostral Neospora titer of 20,480. Clinically, this calf had depressed conscious proprioception in all limbs. Very mild lesions were found in the central nervous system, but protozoa were not found in the tissues. The results demonstrate that the bovine Neospora protozoa can be transplacentally transmitted, resulting in fetal infection and death, and mimics the naturally occurring fetal disease.


Author(s):  
Deebah Choudhary

Aim: The aim of this study was to evaluate the canal cleaning efficacy of these three file systems using scanning electron microscopy. Place and Duration of Study: The study was conducted in the Department of Conservative dentistry and Endodontics, Institute of Dental Sciences Sehora, between October 2020 and December 2020. Materials and Methods: Access cavity preparation was performed on sixty extracted human mandibular premolar teeth and working length was determined. The samples were randomly divided into three groups (n=20) depending upon the file system used i.e. Group 1 (Reciproc Blue), Group 2 (Waveone Gold) and Group 3 (F360). Samples were split into two halves by creating longitudinal grooves on the buccal and lingual surfaces. The samples were sputter-coated with gold and examined under scanning electron microscope at 5000X. The dentinal wall of root canal at coronal, middle and apical thirds of each sample were evaluated for the presence of determining the canal cleanliness and then analyzed using a five-score index. Results: The results of this study revealed that Group 1 (Reciproc Blue) exhibited better cleaning efficacy than samples of Group 2 (WaveOne Gold) and Group 3 (F360) at different locations in the canal i.e. coronal, middle and apical. The mean debris present was highest in coronal area for both group 2 and group 3 i.e. 2.1 and least was seen in apical area of group 1 i.e. 0.3. (p<0.05) Conclusion: Reciproc Blue single-file showed highest cleaning efficacy followed by Waveone Gold and F360. Reciproc file also showed effective cleaning in the apical third of the canal.


2021 ◽  
Vol 11 (Suppl. 1) ◽  
pp. 67-73
Author(s):  
Ahmet Akay ◽  
Özkan Adıgüzel ◽  
Seda Erkan Akay ◽  
Sadullah Kaya

Aim: The purpose of this in vitro study is to compare the cyclic fatigue resistance of Reciproc Nickel-Titanium (Ni-Ti) rotary files while operating root canals using in three different reciprocal angles. Methodology: Forty-five pieces of Reciproc R25 canal files were tested using artificial canals with a 60° angle of curvature, 5 mm curvature radius, and 1.5 mm diameter carved into a stainless steel block. The Ni-Ti files were checked with a stereomicroscope and then randomly separated into 3 groups. Group 1 consisted of reciprocal angles CCW 150°–CW 30°, Group 2 consisted of CCW 180°–CW 60°, and Group 3 consisted of CCW 210°–CW 90°. The duration of the cyclic fatigue being measured, elapsed time until a file fractured was determined with a chronometer. The lengths of the fractured pieces were measured with a digital caliper. After the cyclic fatigue test, two samples from each group were examined with a Scanning Electron Microscope (SEM) to determine the signs of cyclic fatigue. Results: One-way analysis of variance (ANOVA) was applied to the normally distributed groups (p<0,05). Since there was a significant statistical difference of file’s cyclic fatigue resistance (p=0,001) between the groups, Tukey’s honestly significant difference (HSD) post-hoc pairwise comparison test were used for determine to between which groups. While there were statistically significant differences between Group 1 and Group 2 (p=0,001), and between Group 1 and Group 3 (p=0,001), there was no significant difference between Group 2 and Group 3 (p=0,376). Group 1 displayed the highest resistance to cyclic fatigue. There were no statistically significant differences between the lengths of the fractured files within the three groups according to the one-way analysis of variance (p=0,847). Conclusion: In our study, it was observed that the reciprocal angles of CCW 150°–CW 30°, which were also suggested by the file manufacturer firms, had the highest fracture resistance against cyclic fatigue.   How to cite this article: Akay A, Adıgüzel Ö, Erkan Akay S, Kaya S. Comparison of cyclic fatigue of a reciprocating file system at different angles of rotation. Int Dent Res 2021;11(Suppl.1):67-72. https://doi.org/10.5577/intdentres.2021.vol11.suppl1.11   Linguistic Revision: The English in this manuscript has been checked by at least two professional editors, both native speakers of English.  


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