A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)

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Influence of Methodologic Aspects on the Results of Implant-Abutment Interface Microleakage Tests: A Critical Review of In Vitro Studies

Purpose: This study sought to evaluate the influence of methodologic aspects on variations in the findings of in vitro microleakage studies of the implant-abutment interface. Materials and Methods: The MEDLINE, EMBASE, and Cochrane Library databases were consulted for in vitro studies published between 1990 and August 2011. Date from the studies that met the inclusion and exclusion criteria were arranged in tables and subjected to descriptive analysis. Results: Twenty-one studies were found to be eligible for the analysis after application of the inclusion/exclusion criteria. Sixteen studies used bacteria (76.2%), one used a bacterial toxin (4.76%), one used saliva (4.76%), two employed dyes (9.52%), and one used a combination of dyes and bacteria (4.76%). Eight studies evaluated microleakage from the inner portion of the implant to the external portion (38.1%) and nine examined the reverse (42.85%), while four studies investigated the relationship between them (19.05%). The volume inoculated inside the implants ranged from 0.1 to 5.0 mL. The bacterial concentrations used in the tests ranged from 2.41 x 10(6) to 8 x 10(8) colony-forming units/mL. Oral bacterial flora; mixtures of bacteria, toluidine blue, and gentian violet; and lipopolysaccharide of Salmonella enterica bacterial toxins were used. The monitoring period of test results ranged from 24 hours to 11 weeks for bacteria, 5 minutes to 7 days for dye, and 7 days for bacterial toxins. In four studies, microleakage was correlated with the size of the implant-abutment microgap. The external-hexagon implant configuration showed the greatest microleakage, followed by internal-trilobe, internal-hexagon, and internal-taper configurations. Conclusion: The lack of standardization hinderd comparisons of the studies and could explain the divergent results. It is suggested for future studies that special emphasis be placed upon inoculation and analysis of the specific volume for each system, lower concentrations of inoculated bacterial suspensions, and shorter follow-up time when using bacteria. INT J ORAL MAXILLOFAC IMPLANTS 2012;27:793-800.27479380

Micro-leakage at the implant-abutment interface with different tightening torques in vitro

Objectives: This study evaluated the microleakage at the implant/abutment interface of external hexagon (EH) implants and abutments with different amounts of bacteria and tightening torques. Material and Methods: A bacterial suspension was prepared to inoculate the implants. The first phase of this study used nine EH implants and abutments that were divided into three groups with different amounts of bacterial suspension (n=3): V0.5: 0.5 mu L; V1.0: 1.0 mu L e V1.5: 1.5 mu L, and tightened to the manufacturer's recommended torque. The second phase of this experiment used 27 assemblies that were similar to those used in the first phase. These samples were inoculated with 0.5 mu L of bacterial suspension and divided into three groups (n=9). T10: 10 Ncm; T20: 20 Ncm and T32: 32 Ncm. The samples were evaluated according to the turbidity of the broth every 24 hours for 14 days, and the bacteria viability was tested after that period. The statistical evaluation was conducted by Kruskal-Wallis testing (p<.05). Results: During the first phase, groups V1.0 and V1.5 was presented with bacterial contamination in all samples after 24 h. During the second phase, two samples from group T10 and one from T20 presented positive results for bacterial contamination. Different amounts of bacterial solution led to overflow and contamination during the first 24 h of the experiment. The tightening torques did not statistically affect the microleakage in the assemblies. However, the group that was tightened to 32 Ncm torque did not show any bacterial contamination. Conclusion: After 14 days of experimentation, the bacteria were proven to remain viable inside the implant internal cavity.20558158

Influence of Abutment Screw Design and Surface Coating on the Bending Flexural Strength of the Implant Set

The purpose of this study was to analyze the influence of the setting and the presence of solid lubricant on the abutment screw surface on the flexural strength of the joint implant/abutment/screw. Forty abutments were connected to external hex implants, divided into 4 groups (n = 10): FE (titanium alloy screw threaded in the extremity), LE (titanium alloy screw with solid lubricant and thread in the extremity), FT (titanium alloy screw with threaded in all its length), and LT (titanium alloy screw with solid lubricant and thread in all its length). Through the mechanical flexural test, the implant/abutment resistance was evaluated with load applied perpendicular to the long axis in a mechanical testing machine (EMIC) under a speed of 0.5 mm/min. Data were submitted to a statistics test, and results showed statistically significant differences between the FE group and the other groups, and the FE group showed the lowest values. The LE group showed greater values than the LT group, and the values were statistically significant. According to the methodology used, it can be concluded that within noncoated titanium screws, a screw threaded along its entire length provided greater rigidity to the implant set, while with the screw containing solid lubricant, the screw threaded in all its length provided less rigidity of the implant set than screws with the thread only on the end. Among screws with the same geometry, those with the solid lubricant are statistically higher than those which do not have threads just at the end, but those with threads along their entire length do not show statistically significant differences.40212312

Reciprocal fusion transcripts of two novel Zn-finger genes in a female with absence of the corpus callosum, ocular colobomas and a balanced translocation between chromosomes 2p24 and 9q32

We have identified a female patient with a complex phenotype that includes complete agenesis of the corpus callosum, bilateral periventricular nodular heterotopia, and bilateral chorioretinal and iris colobomas. Karyotype analysis revealed an apparently balanced, reciprocal, de novo chromosome translocation t(2;9)(p24;q32). Physical mapping of the translocation breakpoint by fluorescence in situ hybridization and PCR analysis led to the identification of two novel, ubiquitously expressed, Zn-finger-encoding transcripts that are disrupted in this patient. Unexpectedly, the rearrangement produced in-frame reciprocal fusion transcripts, making genotype-phenotype correlation difficult

Prevalence of sinus floor elevation procedures and survival rates of implants placed in the posterior maxilla

The aim of this study was to assess the prevalence of sinus-lifting procedures and survival rates of implants placed in the posterior maxilla. This retrospective chart review examined consecutive patients with tooth/teeth loss in the posterior maxilla between 2008 and 2012 treated with sinus lift, when needed, and implant insertion. Demographic variables, health status, residual alveolar bone height, augmentation types, the implant position, diameter and height, and implant failure, prosthesis types, and the marginal bone loss were recorded. The study included 302 patients at a mean age of 5.2 years, who received a total of 609 dental implants. A total of 380 (62.3%) implants were inserted in native areas, 203 (33.3%) ones in external sinus-lifted areas and 26 (4.4%) ones in internal lifted areas. The survival rate in native or internal lifted areas were 100% and 95.6% in external sinus lifted ones (10 implant failures/203 implants). Almost half of the implants were examined radiologically with a mean duration of 30 months and the mean marginal bone loss was 0.64 ± 1.2 mm. The results showed that the survival rates of native bone and the internal sinus lifting were slightly higher than that of external sinus lifting. Implants placed with sinus augmentation exhibited more marginal bone loss than implants in native bone