Stature Estimation of an Individual Using Nasal, Facial, and Palatal Height among Tamil Nadu Population.

BACKGROUND: Stature estimation in human identification has a significant forensic importance. The stature correlates positively with bones or human body parts. Measurements of various body parts such as the arm, leg, feet, and finger can be used to estimate stature. This study is done to correlate the stature of person with facial, nasal, and palatal height among Tamil Nadu population. AIM AND
OBJECTIVE: The aim and objective was to determine an individual's stature using facial, nasal, and palatal height and to find out the most reliable parameter to determine the stature of the person.
MATERIALS AND METHODS: Anthropometer, Vernier caliper, and palatometer were used for the analysis. The initial pilot study included 20 individuals. The representative study included 100 individuals of age 21-25 years. (Group 1 - males, Group 2 - females). Values of the three parameters (nasal, facial, and palatal) are calculated and related to that of the person's stature.
RESULTS: The quantitative data collected from the subjects are studied using (Pearson correlation) statistical analysis. The quantitative data availed from nasal height were found to be more reliable compared to the other two data in stature prediction. Correlation between stature and nasal height shows a significant positive correlation among the female group (2) with (P- value = 0.57).
CONCLUSION: This study may play a significant role in case of human identification immediately after mass disasters and certain criminal investigations. Further studies with larger samples may produce more reliable values. Copyright:

INTRODUCTION

Forensic odontology is one of the most unexplored and intriguing branches of forensic sciences that primarily deals with identification, based on recognition of unique features present in an individual's dental structures.[1] Forensic odontology has been defined by the Federation Dentaire Internationale as “that branch of dentistry which, in the justice deals with the proper evaluation and presentation of dental findings.”

Forensic identification is a multidisciplinary team effort relying on positive identification methodologies as well as presumption or exclusionary methodologies. Typically, this effort involves the cooperation and coordination of forensic pathologists, forensic odontologists, forensic anthropathologists, serologists, criminalistics, law enforcement officials, and other specialists as deemed necessary.[2]

Estimating stature, along with age, sex, and race, is one of the four pillars of the anthropological protocol and may be essential in preliminary screening and reconstructive identification of skeletal remains.[3] Stature is shown to have a definite and proportional relationship with many parts of the human body such as the cranial and facial bones, long bones, trunk, and foot bones.

The purpose of this study is, therefore, to determine the usefulness of facial, nasal, and palatal height to predict the stature of an individual. This study might serve as reference data in forensic odontology as well as informative to dental practitioners in providing clinical information and education in this part of the world.

Forensic science

Forensic science is primarily concerned with the application of science in court or legal proceedings. Without a proper structured forensic science education, These concepts are often not fully understood and forensic science cannot realize its true potential.[4]

Forensic odontology is a major branch of forensic science, which is an identification discipline based on the recognition of unique features present in each person's dental structures. It relies on the detailed knowledge of the teeth and jaws possessed by a dentist.[5] Dental tissues are the strongest in the human body, and therefore, their characteristics remain unchanged even after long periods of stay in extreme environments.

Forensic odontology relies on the ability to identify, collect, study, and compare information from oral and facial structures. The application of forensic odontology in the fields of forensics is ever increasing and includes:

Identification of unknown decedents by the teeth, jaws, and craniofacial bones

Recognition of victims of mass disasters

Age estimation of both living and deceased persons including neonatal remains

Analysis of bite marks found on victims of attack

Investigation of family violence

Contribution to anthropological and archeological research

Dental jurisprudence including expert witness.

Stature determination

Stature comes from the Latin word statura, meaning “height, size of body growth”. Stature is measured as a vertical distance from the vertex to the floor. For establishing identity, stature is an important parameter in medicolegal and forensic examination. There is a definitive biological correlation of stature with body parts such as extremities, head, trunk, and vertebral column.

Estimating stature is an important step in the reconstructive identification of skeletonized and disremembered human remains. While numerous body parts such as the skull and long bones have been used for the purpose, the dentition has seldom been applied.

Establishment of alternative methodologies for personal height estimation is important for a number of reasons. Conventionally, stature was predicted by using cranial dimensions, cranial sutures, length of head, and odontometry.[6]

Facial height is the distance from nasion (which is the most anterior point of the frontonasal suture that joins the nasal part of the frontal bone and the nasal bones. It marks the midpoint at the intersection of the frontonasal suture with the internasal suture joining the nasal bones) to menton (the lowest point in the median plane of the chin) of the mandible.[7]

Nasal height is the distance from nasion to nasospinale (the point of intersection of a line uniting the lowest points on the margin of each nasal opening with the midsagittal plane).[8]

MATERIALS AND METHODS

Ethical consideration

The study was approved by the ethical committee of our university. The details of the study were explained to all subjects and written and verbal informed consent was obtained from all subjects before entering into the study. Subjects of the study were recruited from the outpatient department of Adhiparasakthi Dental College.

Inclusion criteria

Inclusion criteria for this study are those subjects with a complete set of fully erupted teeth, periodontally healthy teeth, normal overjet and overbite, and with absent spacing in the anterior teeth and with normal molar and canine relationship.

Exclusion criteria

Patients who are not included in this study are those who had deleterious oral habits, those undergoing orthodontic treatment, those who had a history or clinical evidence of cleft palate, those who underwent orthognathic surgery or trauma and prosthetic appliances, and and those who had a history or clinical features suggestive of endocrinal disorders and developmental disorders.

Sample size

Hundred subjects of age varying from 18 to 28 years were included in the study, of which:

50 were male (Group 1)

50 were female (Group 2).

Armamentarium

For patient screening:

Mouth mirror

Probe

Tweezer

Sterile surgical gloves

Mouth mask.

For sample collection:

Sterile surgical gloves

Cotton and cotton holder

Rubber bowl

Spatula

Anthropometer (MedPlus)

Depth gauge (Kristeel)

Impression trays – Dentulous perforated

Alginate impression material – TropicalginR

Dental stone – Type IV Alpha Dihydrate Calcium Sulfate (Ultra RealR)

Vibrator (Unident™)

An electronic digital Vernier caliper up to two decimal places.

Methodology

Stature estimation

Stature was measured as the vertical distance from the vertex to the floor. The measurement was obtained by making the subject stand erect and barefooted with the heels in close contact with each other on a firm horizontal resting plane. The subject's back was positioned as straight as possible and achieved by rounding or relaxing the shoulders, with the shoulder blocks and buttocks touching the vertical plane.[9] The head was oriented in the Frankfurt Horizontal Plane, which was achieved by adjusting the face such that the lateral palpebral commissure and the tip of the pinna were in a horizontal plane parallel to that of the feet. An anthropometer with one arm sliding against the vertical plane was brought down on to the subject's head and the stature read off the scaled vertical plane. Stature was re-measured on 20 randomly selected subjects, also to assess possible intra-observer differences.

Measurement of facial height

Measurement of facial height

Facial height estimation [Figure 2]

The face, comprising pair of eyes and ears, nostrils, and the mouth, is described as the anterior aspect of the head from the forehead to the chin and from one ear to the other. Each subject was made to sit in a relaxed and upright position with the head in an anatomical position while taking measurements.[10] The parameters were taken using a sliding digital Vernier caliper. Facial height was measured from the nasion to the menton of the mandible. A digital Vernier caliper was used. The Vernier caliper is calibrated in inches and millimeters. The data taken in millimeters were converted to centimeters.

Measurement of nasal height

Nasal height estimation [Figure 3]

The nose is the part of the respiratory tract superior to the hard palate and contains the peripheral organ of smell. It includes the external nose and nasal cavity, which is divided into the right and left cavities by the nasal septum. The nasal height was measured from the nasion to the nasopinale.

Measurement of palatal height

Palatal height estimation [Figure 4]

The hard palate is the bony structure that forms the division between the oral and nasal cavities and maintains a close relationship with the functional orofacial activities. The harmonious growth of the face and the proper development of breathing, sucking, chewing, swallowing, and speech depend on the balance of the hard palate with the other structures of the sensory-motor-oral system because the hard tissues are closely related to function.

Standardization

Strict standardization of the dental materials and impression procedure was adhered. Irreversible hydrocolloid material (alginate) of the dustless, normal setting variety (Tropicalgin™), was selected for impression procedure. Die stone (Ultra Real) was used to pour the impressions. Impression trays and other instruments were cleaned and sterilized as recommended.

Fabrication of dental casts

After verbal and written consent, dental casts were made using alginate impression material and die stone with the aid of a vibrator as per the manufacturers' recommendations.[11] Palatal height is measured using the depth gauge. A straight line is drawn from the incisive papilla behind the central incisors along the midline of the palate. A perpendicular line intersecting the straight line is drawn joining the mesiobuccal cusps of the maxillary first molar on either sides. A depth gauge is used to measure the depth of the palatal vault.[12]

Data presentation and analysis

The data analysis in this present study was carried out using the Statistical Package for the Social Sciences (Spss 17.0 Software Spss 17.0 Integrated Student Version By Inc. Spss Inc.,). The minimum, maximum, mean, and standard deviations of the variables are presented. Pearson correlation was then applied to test the relationship between stature and nasal, facial, and palatal dimensions and the results were obtained [Tables 1–5]. Pearson's correlation analysis was used to compare the mean of stature with that of the facial height, nasal height, and palatal height for 100 subjects to get the most reliable parameter. Linear regression analysis is used to derive the formula to predict the stature using one of the parameters.

Table 1

Distribution of nasal, palatal, facial, and height of Group 1 individuals

Descriptive statistics	Mean	SD
Nasal height	47.8164	3.18671
Facial height	110.5784	5.58304
Palatal height	21.060	1.3911
Height of the individual	1687.580	72.1379

SD: Standard deviation

Table 5

Correlation of nasal, palatal, facial, and height of Group 2 individuals

R 2	Adjusted R2	F	Significance
0.074	0.054	3.813	0.057*

DISCUSSION

Dental identification of humans occurs for a number of different reasons and in a number of different situations. The bodies of victims of violent crimes, fires, motor vehicle accidents, and workplace accidents can be disfigured to such an extent that identification by a family member is neither reliable nor desirable. Persons who have been deceased for some time prior to discovery and those found in water also present with unpleasant and difficult visual identifications.

Dental identification has always played a key role in natural and humanmade disaster situations and in particular, the mass casualties normally associated with aviation disasters. Due to the lack of a comprehensive fingerprint database, dental identification continues to be crucial in identification.[13]

Anthropologists have always had an interest in studying variations in morphological characters. Anthropometry is a series of systematized measuring techniques that expresses quantitatively the dimensions of the human body and skeleton.[14] There is a correlation of height of a person with his body parts such as upper and lower limbs or its parts, head, trunk, and vertebral column. Many studies have been carried out for estimation of stature from measurements of various body parts such as the arm, leg, feet, and finger and few studies have been done for stature estimation from the face alone.[15] It is a well-established fact that each race requires its own research finding for stature estimation because of ethnic, dietary, and climatic variations. Hence, the results of studies done in one population cannot be applied to other populations. Therefore, there is a need for research study in this region.

In an earlier period, there were studies found for stature prediction using facial height and nasal height. Studies were also conducted to find the gender of an individual using palatal height but not to estimate the stature of an individual. Thus, this study took an effort to predict the stature of an individual using palatal height, mainly along with facial and nasal height.

Predicting stature along with age, gender, and race, is one of the four pillars of anthropology and may be used in screening and identification of skeletal remains. Previously, stature prediction was done using length of cranial sutures, maxillofacial anthropometry, and tooth dimensions. Jagadish and Sowmiya estimated height from length of coronal and sagittal sutures of the skull and reported that sutural length studies are useful in estimating stature.[16] Wankhede et al. used maxillofacial anthropometry for stature estimation and observed that in males, the total facial height had a greater correlation with stature. However, percutaneous facial dimensions are not good predictors of accurate stature estimation and can be used when other parameters are not available.[15] The hard palate is the bony structure that forms the division between the oral and nasal cavities[17] and maintains a close relationship with the functional orofacial activities.[18] The harmonious growth of the face and the proper development of breathing, sucking, chewing, swallowing, and speech depend on the balance of the hard palate with the other structures of the sensory-motor-oral system[19] because the hard tissues are closely related to function.

The configuration of bone structures is genetically determined but susceptible to the molding action of the orofacial muscles. As the function can adapt to the presence of altered shape, bone structure can also be altered by inappropriate usual positioning of the soft tissue in the performance of a specific function and the moments of inactivity. Accordingly, the detailed assessment of anatomical structures helps in understanding the changed functional behavior.

Morphological analysis of the hard palate is characterized as an important part of the evaluation of orofacial motricity, it contributes to the structuring of a therapeutic plan with strategies, prognosis, and appropriate referrals. When the depth of this structure is altered, it can be expected that oral functions and/or breathing will be impaired to a greater or lesser degree.[20]

CONCLUSION

Correlation between stature and nasal height shows a significant positive correlation among the female group (2) with (P = 0.57). The study may play a significant role in case of human identification immediately after mass disasters and certain criminal investigations.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

Table 2

Distribution of nasal, palatal, facial, and height of Group 2 individuals

Descriptive statistics	Mean	SD
Nasal height	48.0210	2.93127
Facial height	105.6670	4.94690
Palatal height	20.442	1.1252
Height of the individual	1551.000	110.0069

SD: Standard deviation

Table 3

Correlation of nasal, palatal, facial, and height of Group 1 individuals

	Pearson correlation coefficient	P
Nasal height	0.248	0.082
Facial height	0.240	0.093
Palatal height	0.200	0.164

Table 4

Correlation of nasal, palatal, facial, and height of Group 2 individuals

	Pearson correlation coefficient	P
Nasal height	0.271	0.057*
Facial height	0.254	0.075
Palatal height	0.257	0.172

Linear regression analysis: Y=B+aX, Y=Height of the patient, X=Nasal length, Only in Group 2, there is a significant correlation, Y=1062+10.81 (X)