The weak evidence of lip print analysis for sexual dimorphism in forensic dentistry: a systematic literature review and meta-analysis

Analysis of total lip score system and total groove score for gender identification: A cross-sectional study

Background

Endless ink and pixel space have been spent to validate the use of cheiloscopy classification systems in the field of identification. It is becoming evident that lip-print patterns may provide indications about an individual's gender, race, occupation, habits, blood type, and paternity. Over the course of time, much data have been collected on a substantial population in this field. In the present study, we strive to see how well a noble total lip scoring (TLS) system works in identifying a person's gender among the College of Dentistry students. We also quantified the total groove score (TGS) and compared it with each quadrant for better authentication of the set study design.

Materials and Method

A cross-sectional descriptive study was conducted among 60 dental students (30 males and 30 females), with an age range of 18-30 years. Lip prints were recorded using the writing pad method and subsequently digitalized by capturing the images using Adobe Photoshop CS 6 Extended Version, counted and summed up, quadrant-wise, in both upper and lower lips. The TLS and TGS between males and females were statistically calculated using the Jamovi project.

Results

The mean value for TLS for males (n = 402; SD ± 92.1) is higher than that for females (n = 348; SD ± 86.1). The correlation matrix applying a non-parametric test for non-continuous data using Spearman's ratio inferred a statistically significant correlation (-0.354) with a P-value of 0.005 for TLS, whereas a correlation (-0.162) of TGS with gender was not so significant with a P-value of 0.217.

Conclusion

Our study proved the uniqueness of applying TLS as a novel approach to gender identification. The study revealed that males had a statistically higher lip score than females.

Clinical Significance/Future Implications

Being unique, our study inferred the importance of TLS, which needs to be explored in detail for applying, evaluating, and validating its accuracy in forensic research that can help for errorless investigations as full-proof evidence in court.

Cheiloscopy in sex estimation: a systematic review

This study aimed to conduct a systematic review to gather evidence to clarify if cheiloscopy can be used in sex estimation and identify the reasons behind the lack of consensus in the scientific community. The systematic review was performed following the PRISMA guidelines. A bibliographic survey was conducted in PubMed, Scopus, and Web of Science databases, restricted to articles published between 2010 and 2020. Studies were selected according to eligibility criteria, and then the study data were collected. The risk of bias in each study was assessed and applied as additional inclusion or exclusion criteria. The results of the articles eligible for analysis were synthesized using a descriptive approach. In the 41 included studies, several methodological flaws and variations between studies that contribute to the discrepancy in results were identified. The data gathered allowed us to conclude that there is no strong scientific evidence to support the use of cheiloscopy in sex estimation, as there is no specific pattern for each sex, which reduces the criminalistic interest of cheiloscopy in estimating this parameter.

Global bibliometric mapping of dental development research for the period 2012-2021

BACKGROUND

Dental development is a complex long-term biological process, significant attention should be paid to the dental development and health of this critical time window in childhood for the oral health of the whole life cycle.

AIM

This study aimed to conduct bibliometric studies on the scientific outputs of global dental development research by the CiteSpace software.

DESIGN

The global scientific outputs about dental development between January 1, 2012, and December 31, 2021, retrieved from Web of Science Core Collection, CiteSpace, and Microsoft Excel were applied for this bibliometric study.

RESULTS

A total of 3746 reviews and articles were obtained from the Web of Science core database for exploring the basic publication characteristics, hotspots, and frontiers of this research field. The results showed that dental development is gaining more researcher's attention over time. In terms of countries, the USA and China were the major contributors to this research area. At the institutional level, Sichuan University ranked first. Meanwhile, international cooperation across regions was quite active. The Journal of Dental Research has exerted a broad and far-reaching influence on dental development research in both publications and citations. James P Simmer, Jungwook Kim, Charles E Smith, and Jan CC Hu are among the most influential scholars in this field. Finally, the future hotspots were proposed, covering three directions: dental analysis, tooth development, and post-translational phosphorylation of histones.

CONCLUSION

In the past decade, the field of dental development has developed rapidly, and the cooperation between scholars, institutions, and researchers has become increasingly close.

Pattern recognition of grooves in human lips for improved authentication in cyber-physical systems using U-Net architecture

Latent Lip groove application is been a notable topic in forensic applications like crime and other investigations. The detection of lip movement is been a challenging task since it is a smaller integral part of the human face. The conventional models operate on the available public or private dataset but it is constrained to the large population and unconstrained environment. The study aims at developing a deep learning model in a multimodal system using the deep U-Net Convolutional Neural Network architecture. It also aims at improving biometric authentication through a deep pattern recognition that involves the feature extraction of grooves present in the human lips. An examination of grooves present in the input lip image is conducted by the present system to check the authenticity of the person entering the cyber-physical systems. The lip images are collected from the public security cameras via high-definition cameras in crowded areas that help the proposed method in forensic investigation and further, it considers various unconstrained scenarios to improve the efficacy of the system. The study involves initially pre-processing of lip image, and feature extraction of lip grooves to improve the efficacy of the lip trait. The simulation is conducted on the MATLAB tool to examine the efficacy of the model against various existing methods. Further, the study does not take into account the datasets available on the websites and lip images are only collected from a large set population in a real-time environment. The results of the simulation show that the proposed method achieves a higher degree of accuracy in extracting the grooves from the input lip images.