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Human identification via dental comparison is only possible if sufficient antemortem dental records are available. These records are sourced from dental practices. New 3D digital technologies are increasingly being used by dentists in Australia for routine clinical procedures and offer significantly more data for individualizing people than traditional 2D records. However, it is uncertain whether clinicians are aware of the importance of these records for forensic purposes. The collection of antemortem records from clinical practices is critical to successful identification by forensic odontology. A survey across 71 dental practices in South Australia explored both the availability of 3D dental records and the level of awareness among practitioners regarding their significance in forensic investigations. While 3D dental records are frequently produced in dental settings, there is a notable lack of awareness among practitioners of their critical value in forensic contexts. Retention practices for all records were highly variable. Despite the production of 3D records, their potential remains underutilized due to gaps in knowledge of forensic applicability. The findings highlight a significant opportunity for enhancing forensic identification through better education and management of 3D dental records. Addressing this gap is essential for improving the efficiency of forensic odontology. [ABSTRACT FROM AUTHOR]

Aim: Intra-oral 3D scanning of dentitions has the potential to provide a fast, accurate and non-invasive method of recording dental information. The aim of this study was to assess the reliability of measurements of human dental casts made using a portable intra-oral 3D scanner appropriate for field use.Method: Two examiners each measured 84 tooth and 26 arch features of 50 sets of upper and lower human dental casts using digital hand-held callipers, and secondly using the measuring tool provided with the Zfx IntraScan intraoral 3D scanner applied to the virtual dental casts. The measurements were repeated at least one week later. Reliability and validity were quantified concurrently by calculation of intra-class correlation coefficients (ICC) and standard errors of measurement (SEM).Results: The measurements of the 110 landmark features of human dental casts made using the intra-oral 3D scanner were virtually indistinguishable from measurements of the same features made using conventional hand-held callipers. The difference of means as a percentage of the average of the measurements by each method ranged between 0.030% and 1.134%. The intermethod SEMs ranged between 0.037% and 0.535%, and the inter-method ICCs ranged between 0.904 and 0.999, for both the upper and the lower arches. The inter-rater SEMs were one-half and the intra-method/rater SEMs were one-third of the inter-method values.Conclusion: This study demonstrates that the Zfx IntraScan intra-oral 3D scanner with its virtual on-screen measuring tool is a reliable and valid method for measuring the key features of dental casts. [ABSTRACT FROM AUTHOR]

In future warming scenarios, decreasing ratios of snow to rain will have implications on streamflow generation in mountain areas. One hypothesis is that warmer winter temperatures will lead to a reduced snowpack and an earlier and slower melt, potentially decreasing streamflow. Variations in streamflow will control nearshore fate as snowmelt timing may determine lake inflow mixing and seasonal variation in nutrient fluxes. However, the mechanisms controlling streamflow generation in mountain areas are still elusive. In this work we explore how different snow-to-rainfall ratios influence streamflow generation in seven catchments around Lake Tahoe. Lake Tahoe is a deep (500 m), oligotrophic lake, positioned at the snowline (1900m) in the Sierra Nevada Mountains (CA/NV, USA) and renowned for its clarity (average annual Secchi depth greater than 20 m). As a long-term study site, extensive data have been collected since 1967 on both the basin hydrology and lake conditions. The total watershed area is 800 km2 and the catchments we analyzed range in size from 15 to 140 km2. Daily streamflow data was obtained through USGS and daily SWE data from SNOTEL as well as Sierra Nevada Snow Reanalysis Data. Our preliminary analysis indicates that there is a significant variation in the amount of streamflow for different SWE to precipitation ratios (SWE2P). Snowmelt is usually slower in warmer years and there is less streamflow in years with a smaller SWE2P. It seems that there is a threshold of 500 mm where total streamflow starts to increase proportionally to winter peak SWE, below that threshold total streamflow is not sensitive to the amount of snow in the catchment. There are differences in both the SWE2P and on streamflow signatures of the catchments on the east and west sides of the lake. For its unique location and dataset, we believe Lake Tahoe data provides a good opportunity for further studies on climatic and physiographic controls of snowmelt and streamflow generation in mountain areas. [ABSTRACT FROM AUTHOR]