An Expanded Surgical Corridor of Oblique Lateral Interbody Fusion at L4–5: A Magnetic Resonance Imaging Study

Objective We introduced a new preoperative method, the “expanded surgical corridor,” to evaluate the actual safety corridor, which may expand the possibility of performing oblique lateral interbody fusion (OLIF). Methods Axial T2-weighted magnetic resonance images at the L4–5 disc level of 511 lumbar degenerative disease patients was evaluated. The distance between the medial edge of the left-sided psoas muscle and the major artery was measured as the conventional surgical corridor (CSc). The distance between the major vein and lumbar plexus was measured as the expanded surgical corridor (ESc). Results The mean CSc and ESc were 13.9 ± 8.20 and 37.43 ± 10.1 mm, respectively. No surgical corridor was found in 7.05% of CSc and 1.76% of ESc, small corridor (≤ 1 cm) was found in 27.40% of CSc and 0.59% of ESc, moderate corridor (1–2 cm) was found in 42.07% of CSc and 1.96% of ESc, and large corridor (> 2 cm) was found in 23.48% of CSc and 95.69% of ESc. A total of 33.83% (45 of 133) of whom were preoperatively categorized as having a limited surgical corridor by conventional measurement, underwent OLIF L4–5 successfully. Conclusion By using the ESc, only 2.35% were categorized as having a limited surgical corridor. The other 97.65% of the patients had an approachable corridor that could be successfully operated by experienced spine surgeons who employ meticulous surgical dissection and thorough understanding of the anatomical structures. The ESc may represent true accessibility to the disc space for OLIF, particularly at the L4–5 level

Low-cycle fatigue of NiTi rotary instruments in hypochlorite

published_or_final_versionDental SurgeryMasterMaster of Dental Surger

Increasing use of Bioceramics in endodontics: A narrative review

Successful outcomes of root canal treatment, in addition to a multitude of factors, also depends on the prevention of reinfection of the root canal space. The ultimate goal of root canal treatment is prevention or healing of apical periodontitis. The use of biologically active materials to seal root canal systems has been extensively proposed in contemporary endodontics to realise this goal. There are several commercial formulations of bioceramics available based on minor variations in composition which could have potentially important changes in properties in the clinical situation. This narrative review serves to provide brief information on the different formulations of bioactive ceramics that are available to a dentist.link_to_OA_fulltex

Electropolishing enhances the resistance of nickel-titanium rotary files to corrosion-fatigue failure in hypochlorite

Introduction: The aim of this study was to examine the fatigue behavior, especially at the low-cycle fatigue (LCF) region, of an experimentally electropolished FlexMaster and a commercial electropolished nickel-titanium (NiTi) instrument (RaCe) in a corrosive environment. Methods: A total of 90 NiTi rotary instruments were subjected to rotational bending at various degrees of curvatures while immersed in 1.2% sodium hypochlorite solution until broken. The maximum surface strain amplitude, calculated from the curvature of the instrument and the diameter of the cross section at break, was plotted against the LCF life. The results were compared with data for a non-electropolished commercial product tested by using the same methodology. Results: The fatigue life of both instruments generally declined with increasing surface strain amplitude; there was a significant difference between the 2 instruments. Comparing the surface-treated FlexMaster with its commercially available non-electropolished counterpart, an improved resistance to fatigue breakage as a result of electropolishing was noted (P < .05). Conclusions: The LCF life of a NiTi instrument rotating with a curvature in a corrosive environment is enhanced by electropolishing. The design, both cross-sectional and longitudinal, appears to have an effect on the fatigue behavior of NiTi rotary instruments. © 2010 American Association of Endodontists.link_to_subscribed_fulltex