Comparison of Human and Porcine Natural Tooth Fluorescence-A Scoping Study to Inform Research on Dental Materials and Forensic Dentistry.

Objectives: Understanding human tooth structure fluorescence aids clinical and forensic dentistry, enabling tissue/material differentiation and the creation of esthetic restorative materials. Material manufacturers seek to replicate natural tooth fluorescence, necessitating the development of novel techniques to detect them. Procuring human teeth for research is challenging due to ethical and infection control standards, prompting a search for alternative models.

From clean spaces to crime scenes: Exploring trace DNA recovery from titania-coated self-cleaning substrates.

Titanium dioxide (titania, TiO) is frequently used as a coating for a variety of self-cleaning products, such as antifogging vehicle mirrors, ceramic tiles, and glass windows because of its distinct physiochemical features. When exposed to light TiO causes photocatalytic decomposition of organic contaminants, potentially compromising DNA integrity. The impact of TiO-coated commercial glasses, Bioclean® and SaniTise™, on trace DNA persistence, recovery, and profiling was investigated.

Metal-DNA interactions: Exploring the impact of metal ions on key stages of forensic DNA analysis.

Forensic DNA analysis continues to be hampered by the complex interactions between metals and DNA. Metal ions may cause direct DNA damage, inhibit DNA extraction and polymerase chain reaction (PCR) amplification or both. This study evaluated the impact of metal ions on DNA extraction, quantitation, and short tandem repeat profiling using cell-free and cellular (saliva) DNA.

Quantitative PCR overestimation of DNA in samples contaminated with tin.

Metals can pose challenges while conducting forensic DNA analysis. The presence of metal ions in evidence-related DNA extracts can degrade DNA or inhibit PCR as applied to DNA quantification (real-time PCR or qPCR) and/or STR amplification, leading to low success in STR profiling. Different metal ions were spiked into 0.

Validity of postmortem computed tomography for use in forensic odontology identification casework.

Forensic Odontology (FO) identification compares antemortem (AM) and postmortem (PM) dental datasets and is widely accepted as a primary identifier. Traditionally, a PM dental examination is undertaken in the same manner as a dental examination conducted for a living patient. Recently, the increased forensic application of computed tomography (CT) offers an alternative source of PM data.

A custom hybridisation enrichment forensic intelligence panel to infer biogeographic ancestry, hair and eye colour, and Y chromosome lineage.

Massively parallel sequencing can provide genetic data for hundreds to thousands of loci in a single assay for various types of forensic testing. However, available commercial kits require an initial PCR amplification of short-to-medium sized targets which limits their application for highly degraded DNA. Development and optimisation of large PCR multiplexes also prevents creation of custom panels that target different suites of markers for identity, biogeographic ancestry, phenotype, and lineage markers (Y-chromosome and mtDNA).

"Identified", "probable", "possible" or "exclude": The influence of task-irrelevant information on forensic odontology identification opinion.

In a mass disaster situation, identification of the deceased utilising comparison of dental features is frequently heavily relied upon to facilitate rapid and accurate outcomes. The method consists of the comparison of clinical and radiographic records depicting oral structures and dentition to allow an opinion to be produced on a presumed identity. Current forensic odontology identification opinions are expressed as categories of levels of identification.

Ethics reporting in forensic science research publications - A review.

An essential element of compliance with ethical standards in scientific research is the reporting of a verifiable declaration of ethical approval and, when human subjects are involved - informed consent, in published works. The level of reporting of ethical permission for research published in forensic and investigative sciences journals has not been explored to date. Hence, we examined the reporting of ethical approval and informed consent in original research utilising human or animal subjects published in six forensic science journals from 2010 to 2019.

Unveiling forensically relevant biogeographic, phenotype and Y-chromosome SNP variation in Pakistani ethnic groups using a customized hybridisation enrichment forensic intelligence panel.

Massively parallel sequencing following hybridisation enrichment provides new opportunities to obtain genetic data for various types of forensic testing and has proven successful on modern as well as degraded and ancient DNA. A customisable forensic intelligence panel that targeted 124 SNP markers (67 ancestry informative markers, 23 phenotype markers from the HIrisplex panel, and 35 Y-chromosome SNPs) was used to examine biogeographic ancestry, phenotype and sex and Y-lineage in samples from different ethnic populations of Pakistan including Pothwari, Gilgit, Baloach, Pathan, Kashmiri and Siraiki. Targeted sequencing and computational data analysis pipeline allowed filtering of variants across the targeted loci.

Comparison of Isohelix™ and Rayon swabbing systems for touch DNA recovery from metal surfaces.

A previous study evaluating two swabbing systems found that DNA was best recovered from sterile metal substrates using an Isohelix™ swab wetted with isopropyl alcohol rather than a Rayon swab with water as the wetting agent. We tested the same swabbing systems on metal (aluminum, brass, and stainless steel) and plastic substrates in a regularly touched environment to simulate the non-deliberate transfer of touch evidence likely seen in a casework scenario, to ascertain the performance of these swabs in an uncontrolled situation. Higher amounts of touch DNA were recovered with Isohelix™ swabs (0.

The biasing impact of irrelevant contextual information on forensic odontology radiograph matching decisions.

The potential biasing effect of irrelevant context information on the forensic odontology method of radiograph-based identification has never been empirically investigated despite being a recognized problem in other forensic science disciplines. This study examines the effect of irrelevant context information on the probability judgment of match (JOM) of practicing forensic odontologist and dentist participants who were asked to match pairs of dental radiographs supplemented with irrelevant case information. The irrelevant case information contained domain task-irrelevant context information which varied in strength (strong or weak).

Interpretation, confidence and application of the standardised terms: Identified, Probable, Possible, Exclude and Insufficient in forensic odontology identification.

Forensic odontology identification scales are used to express certainty of identifications of deceased persons. These standardized scales are assumed to convey unambiguous expert opinions and facilitate communication between forensic odontologists and end users. However, to date no studies have investigated how the experts interpret and use these scales.

A review of the current understanding of burned bone as a source of DNA for human identification.

Identification of incinerated human remains may rely on genetic analysis of burned bone which can prove far more challenging than fresh tissues. Severe thermal insult results in the destruction or denaturation of DNA in soft tissues, however genetic material may be preserved in the skeletal tissues. Considerations for DNA retrieval from these samples include low levels of exogenous DNA, the dense, mineralised nature of bone, and the presence of contamination, and qPCR inhibitors.

The use of gelling agents to preserve burnt teeth within the dental alveoli for dental human identification - a study utilising sheep mandibles.

Dental comparison is one of the primary methods of scientific identification of severely incinerated human remains. However, due to the fragile nature of the remains dental structures may be lost or damaged during recovery and transportation, limiting the amount of evidence available for examination. In addition to protecting the head, stabilization of the oral structures with an adhesive substance that will not interfere with the dental examination is ideal.

Comparison of bone demineralisation procedures for DNA recovery from burned remains.

Recovering DNA from modern incinerated bones can be challenging and may require alteration of routine DNA extraction protocols. It has been postulated that incinerated bones share some similarities with ancient bones, including fragmented DNA, surface contamination and highly mineralised structure, all of which can inhibit the successful recovery of genetic material. For this reason, ancient DNA extraction protocols are often used for incinerated modern samples; however, their effectiveness is still somewhat unclear.

Evaluation of the efficiency of Isohelix™ and Rayon swabs for recovery of DNA from metal surfaces.

Purpose: We investigated the recovery and extraction efficiency of DNA from three metal surfaces (brass, copper, steel) relevant to forensic casework, and plastic (control) using two different swabbing systems; Rayon and Isohelix™ swabs, with sterile water and isopropyl alcohol respectively, as the wetting solutions.

Methods: Twenty nanograms of human genomic DNA were applied directly to Isohelix™ and Rayon swabs; and to the metal and plastic substrates. All substrates were left to dry for 24 h, followed by single wet swabbing and extraction with the DNA IQ™ System.

A comparison of crystal structure in fresh, burned and archaic bone - Implications for forensic sampling.

Standard protocols for extracting DNA from bone are variable and are largely dependent on the state of preservation. In archaic samples, endogenous DNA is believed to be tightly bound to crystal aggregates in the Hydroxyapatite (HAp) matrix requiring prolonged demineralisation to allow its release. By comparison, fresh bone contains abundant cellular material, discounting the need for demineralisation.

Forensic touch DNA recovery from metal surfaces - A review.

Trace evidence such as touch (also known as contact) DNA has probative value as a vital forensic investigative tool that can lead to the identification and apprehension of a criminal. While the volume of touch DNA evidence items submitted to forensic laboratories has significantly increased, recovery and amplification of DNA from these items, especially from metal surfaces, remains challenging. Currently little is understood with regards to the underlying mechanisms of metal-DNA interactions in the context of forensic science and how this may impact on DNA recovery.

A mini-multiplex SNaPshot assay for the triage of degraded human DNA.

Short Tandem Repeat (STR) genotyping is currently the primary DNA-based method for human identification, however it can have limited success when applied to degraded human remains. Massively parallel sequencing (MPS) provides new opportunities to obtain genetic data for hundreds of loci in a single assay with higher success from degraded samples. However, due to the extra requirement for specialised equipment, expertise and resources, routine use of MPS may not be feasible or necessary for many forensic cases.

Stabilisation of dental structures of severely incinerated victims at disaster scenes to facilitate human identification.

Fatalities due to fire events such as bushfires, domestic and industrial fires and vehicle accident related incineration, leave victims with limited prospects of being accurately identified. Due to their morphology and anatomical position teeth are uniquely protected in incineration cases and via comparison to dental records often provide the only scientifically valid means of identification. However, extreme heat and direct exposure to flame can render the teeth extremely fragile and vulnerable to damage and loss especially during collection and transportation to the mortuary.

Differential nuclear and mitochondrial DNA preservation in post-mortem teeth with implications for forensic and ancient DNA studies.

Major advances in genetic analysis of skeletal remains have been made over the last decade, primarily due to improvements in post-DNA-extraction techniques. Despite this, a key challenge for DNA analysis of skeletal remains is the limited yield of DNA recovered from these poorly preserved samples. Enhanced DNA recovery by improved sampling and extraction techniques would allow further advancements.

Evaluation of carrier RNA and low volume demineralization for recovery of nuclear DNA from human teeth.

Purpose: Teeth and bones are frequently used in the genetic analysis of degraded and ancient human and animal remains. Standard extraction methods, including most commercially available systems, may not yield sufficient DNA to enable successful genetic analysis. Addition of a carrier molecule and demineralization (via EDTA) can increase yields from samples containing limited amounts of DNA.