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Mid-IR spectroscopy is a powerful and label-free technique to investigate protein reactions. In this study, we use quantum-cascade-laser-based dual-comb spectroscopy to probe protein conformational changes and protonation events by a single-shot experiment. By using a well-characterized membrane protein, bacteriorhodopsin, we provide a comparison between dual-comb spectroscopy and our homebuilt tunable quantum cascade laser (QCL)-based scanning spectrometer as tools to monitor irreversible reactions with high time resolution. In conclusion, QCL-based infrared spectroscopy is demonstrated to be feasible for tracing functionally relevant protein structural changes and proton translocations by single-shot experiments. Thus, we envisage a bright future for applications of this technology for monitoring the kinetics of irreversible reactions as in (bio-)chemical transformations. [ABSTRACT FROM AUTHOR]

Purpose: Osseointegrated implants lack a periodontal ligament. Nevertheless, masticatory function in subjects with implant-supported restorations appears similar to function in those with natural dentition. It is not clear how the neurophysiologic mechanisms that modulate jaw movement are associated with osseointegrated implants. This study examined the output from the inferior alveolar nerve during implant loading. Materials and Methods: In 3 dogs, 3 premolars were extracted in the mandible and 2 endosseous titanium implants were placed, allowed to osseointegrate for 3 months, and loaded with vibration force at the threshold response for tooth vibration, at 2× threshold, and at 3× threshold. Neurophysiologic recordings were made from the inferior alveolar nerve during loading of both implants and the adjacent molar and canine. The response magnitude in action potentials in the 50-ms poststimulus period and latency of inferior alveolar afferents in milliseconds were compared following implant loading. Results: Detectable inferior alveolar nerve responses were recorded following loading from both the implants and the teeth at 2× and 3× threshold. However, the response magnitude of teeth (canine, 2.38 ± 0.18 at 2×, 2.78 ± 0.2 at 3×; molar, 2.2 ± 0.16 at 2×, 2.5 ± 0.21 at 3×) was twice that of the implants (anterior, 1.3 ± 0.12 at 2×, 1.68 ± 0.13 at 3×; posterior, 0.8 ± 0.1 at 2×, 1.53 ± 0.15 at 3×). The differences in response magnitude between the teeth and implants were significant (P < .05). The latency of response was similar. Discussion: Management of the occlusion for implant-supported restorations has been empirically developed. An underlying assumption has been that implant-guided jaw function lacks significant proprioception to modulate mastication and related jaw movements. This animal study provides preliminary evidence that force application to implants does elicit a proprioceptive response. Conclusion: Loading of implants does elicit a sensory response that can be observed in the inferior alveolar nerve. The implications are that during occlusal function, information from regions associated with the implant can provide knowledge that could potentially modulate jaw activity in a manner similar to natural teeth. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the effect of cast modifications on denture base adaptation in coronal and sagittal projections following maxillary complete denture processing. Materials and Methods: A total of 60 edentulous maxillary casts (n = 10) were distributed among six groups. Group 1 was the control group with no modification, groups 2 through 6 included a butterfly postdam preparation, groups 3 and 4 also included a 10‐mm wide/4‐mm deep box with addition of four round holes in group 4, and groups 5 and 6 also included a 20‐mm wide/4‐mm deep box with addition of four round holes in group 6. The boxes were prepared at the mid‐heel area of the casts. Two layers of baseplate wax (1 mm each) were used to standardize denture base thickness across the groups. A standard technique was used to replicate the denture tooth set‐up, and standardized processing was done for all the groups. Following deflasking, casts with the dentures were sectioned in the coronal and sagittal directions. Microscopic pictures were taken at preselected points. Data were organized in tables, and statistical analyses were performed using repeated measure ANOVA, Tukey post hoc tests, and post hoc comparison tests set at 5% level of significance. Results: Maximum gaps were measured at the mid‐palatal area followed by nearby areas and the areas near ridge crests in both coronal and sagittal projections. The analyses revealed significant differences between the groups in coronal projection (1/2, 3/4, 5/6) and sagittal projection (1, 2, 3/4, 5/6) without significant differences within the pairs. The groups were ranked from the highest group 1 to the lowest group 6 relative to the gap means. Post hoc comparisons showed that points 1C and 2A had the highest gap means across the study groups. Conclusions: Within the limitations of this study, it can be extrapolated that the denture base adaptation can be effectively increased with the box preparation at the mid‐heel aspect of the casts. Significant reduction of gaps was seen when the box size increased from 10 to 20 mm in coronal and sagittal projections; however, the addition of four holes had no significant effect on gap size alterations. [ABSTRACT FROM AUTHOR]

Statement of Problem: Clinicians use occlusal indicators to identify tooth contacts. However, the reliability of these indicators has been questioned. At times occlusal contacts are not identified or false positive occlusal contacts are observed. Purpose of Study: This study was designed to compare the number and size of occlusal indicator marks from both thick and thin occlusal indicator materials with different loads. Materials and Methods: Ivorine casts were articulated and mounted on an Hana Mate nonadjustable articulator. Loads of 100N, 150N, and 200N were applied with Accufim (25 μm thick, Parkell, Farmingdale, NY) and Articulating Paper (60 μm thick, G.E. Rudischauer Dental Articulating Paper, Brooklyn, NY) as the occlusal indicators. A fresh piece of indicator was used for each trial. Comparisons were made of the number and size of the contacts for both the thick and thin occlusal indicators at the different loads. Results: Observation of the marks recorded with the thicker occlusal indicator demonstrated both a greater number marks and a larger size to the marks when compared to the thinner Accufilm, p ≤ 0.02–0.0001. However, there was no significant increase in the number or size of the marks with an increased load for either material. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2008 [ABSTRACT FROM AUTHOR]

Purpose: To investigate the effect of cast modifications on denture base adaptation in coronal and sagittal projections following maxillary complete denture processing., Materials and Methods: A total of 60 edentulous maxillary casts (n = 10) were distributed among six groups. Group 1 was the control group with no modification, groups 2 through 6 included a butterfly postdam preparation, groups 3 and 4 also included a 10-mm wide/4-mm deep box with addition of four round holes in group 4, and groups 5 and 6 also included a 20-mm wide/4-mm deep box with addition of four round holes in group 6. The boxes were prepared at the mid-heel area of the casts. Two layers of baseplate wax (1 mm each) were used to standardize denture base thickness across the groups. A standard technique was used to replicate the denture tooth set-up, and standardized processing was done for all the groups. Following deflasking, casts with the dentures were sectioned in the coronal and sagittal directions. Microscopic pictures were taken at preselected points. Data were organized in tables, and statistical analyses were performed using repeated measure ANOVA, Tukey post hoc tests, and post hoc comparison tests set at 5% level of significance., Results: Maximum gaps were measured at the mid-palatal area followed by nearby areas and the areas near ridge crests in both coronal and sagittal projections. The analyses revealed significant differences between the groups in coronal projection (1/2, 3/4, 5/6) and sagittal projection (1, 2, 3/4, 5/6) without significant differences within the pairs. The groups were ranked from the highest group 1 to the lowest group 6 relative to the gap means. Post hoc comparisons showed that points 1C and 2A had the highest gap means across the study groups., Conclusions: Within the limitations of this study, it can be extrapolated that the denture base adaptation can be effectively increased with the box preparation at the mid-heel aspect of the casts. Significant reduction of gaps was seen when the box size increased from 10 to 20 mm in coronal and sagittal projections; however, the addition of four holes had no significant effect on gap size alterations., (© 2017 by the American College of Prosthodontists.)