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901.
Purpose The use of titanium for implants has shown the biological acceptance of the metal. Recently, methods of using titanium for restorations, crowns, and bridges have been introduced using both cast and spark erosion systems for fabrication. A potential also exists for using titanium for bonded (Maryland) bridges. Materials and Methods In this study, the potential for bonding titanium was investigated by cementing with various adhesives: (A) metal to metal, (B) metal to enamel, and (C) comparing with a known procedure of bonding nickel-chromium. Truncated cones of pure titanium were fabricated with a 5-mm circular face for bonding to a larger titanium disc embedded in a plastic ring. A special jig was used to pull the bonded cone from the disc on an Instron tensile testing machine (Instron Corporation, Canton, MA). The resin-metal adhesives used were: (1) Infinity, (2) Metabond, (3) All-Bond 2, and (4) Panavia. These were compared with (5) nickel-chromium cones sandblasted and bonded to nickel-chromium with Panavia. Titanium cones were also bonded to human enamel with (6) Panavia and (7) Metabond. The 10 samples in each group were subjected to tensile force, and point of fracture was recorded. The data were subjected to an analysis of variance with a Scheffe F test at the 95% level of significance. Results The results of tensile forces in MPa were (1) Infinity, 28.1 ± 3.6; (2) Metabond, 28.1 ± 1; (3) All-Bond 2, 49.5 ± 4.3; (4) Panavia, 57.9 ± 3.1; (5) Panavia to nickel-chromium, 42.9 ± 6.6; (6) Panavia to enamel, 18.5 ± 4.7; and (7) Metabond to enamel, 19.3 ± 3.5. Titanium was most effectively bonded with All-Bond 2 and Panavia, with Panavia samples significantly better than Panavia to nickel-chromium samples. Conclusions It was concluded that titanium bonded restorations with certain adhesive cements were a definite possibility.  相似文献   
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Background

Transcatheter aortic valve replacement (TAVR) is an increasingly used but relatively expensive procedure with substantial associated readmission rates. It is unknown how cost-constrictive payment reform measures, such as Maryland's All Payer Model, impact TAVR utilization given its relative expense. This study investigated the impact of Maryland's All Payer Model on TAVR utilization and readmissions among Maryland Medicare beneficiaries.

Methods

This was a quasi-experimental investigation of Maryland Medicare patients undergoing TAVR between 2012 and 2018. New Jersey data were used for comparison. Longitudinal interrupted time series analyses were used to study TAVR utilization and difference-in-differences analyses were used to investigate post-TAVR readmissions.

Results

During the first year of payment reform (2014), TAVR utilization among Maryland Medicare beneficiaries dropped by 8% (95% confidence interval [CI]: −9.2% to −7.1%; p < 0.001), with no concomitant change in TAVR utilization in New Jersey (0.2%, 95% CI: 0%–1%, p = 0.09). Longitudinally, however, the All Payer Model did not impact TAVR utilization in Maryland compared to New Jersey. Difference-in-differences analyses demonstrated that implementation of the All Payer Model was not associated with significantly greater declines in 30-day post-TAVR readmissions in Maryland versus New Jersey (−2.1%; 95% CI: −5.2% to 0.9%; p =0.1).

Conclusions

Maryland's All Payer Model resulted in an immediate decline in TAVR utilization, likely a result of hospitals adjusting to global budgeting. However, beyond this transition period, this cost-constrictive reform measure did not limit Maryland TAVR utilization. In addition, the All Payer Model did not reduce post-TAVR 30-day readmissions. These findings may help inform expansion of globally budgeted healthcare payment structures.  相似文献   
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