Evaluation of Twenty Non-Metric Dental Crown Traits in Different Types of Malocclusions in a Sample from India, New Delhi Population.

Background: Dental phenotype shows variation in the form of various metric and non-metric traits, primarily due to gene-environment interplay. It gives an insight into the evolutionary trends, ancestry, and food habits. Recently, it has been explored for genetic affinity with several growth anomalies and development of craniofacial skeleton which is also responsible for dental and skeletal malocclusions. Objectives: the current study aims to investigate the non-metric dental crown traits (NDCTs) using Arizona State University Dental Anthropology system (ASUDAS) in different types of malocclusions in Delhi, National Capital Region (NCR) population. Materials and methods: The study design was observational and retrospective. The total sample comprised of 240 pairs of dental casts divided into four equal groups of 60 subjects each (30 male and 30 female), based on malocclusion. The four groups of malocclusions were: Angle's Class I, Class II division 1, Class II division 2, Class III. The investigator was blinded for patient ID and sex before recording the data. The data for cast were recorded by three observers independently in a modified malocclusion- non-metric dental crown traits (M-NDCT) anthropological variants chart and statistically analyzed for association with different malocclusions and sex. Results: Significant differences were found in the expression of several NDCTs (both in presence and scoring) in different malocclusions. Class I malocclusion showed a predominantly winging, shoveling -upper central and lateral incisor, protostylid, hypoconulid absence in lower second molar, and cusp number. Class II malocclusion showed a double shoveling, interrupted groove, tuberculum dentale, canine mesial ridge, premolar accessory cusp, Carabelli's trait, lingual cusp variation, and seventh cusp in the lower left first molar. Class III malocclusion showed the absence of hypocone in upper second molar, deflecting wrinkle, distal trigonid crest, and Y groove in left lower second molar (26.7%). Besides, sexual dimorphism was seen in shoveling -upper central and lateral incisor, canine mesial ridge, Carabelli's trait, 3-cusp in upper second molar, and cusp number. Conclusions: Significant association was found between non-metric dental traits and malocclusions (Class I, Class division 1, Class II division 2, and Class III). Significant sex-linked differences were also found. Further studies can be performed at multicenter pan-India level with a standard robust protocol and a large sample.

The morphology of the enamel-dentine junction in Neanderthal molars: Gross morphology, non-metric traits, and temporal trends.

This study explores the morphological differences between the enamel-dentine junction (EDJ) of maxillary and mandibular molars of Neanderthals (n = 150) and recent modern humans (n = 106), and between an earlier Neanderthal sample (consisting of Pre-Eemian and Eemian Neanderthals dating to before 115 ka) and a later Neanderthal sample (consisting of Post-Eemian Neanderthals dating to after 115 ka). The EDJ was visualised by segmenting microtomographic scans of each molar. A geometric morphometric methodology compared the positioning of the dentine horns, the shape of the marginal ridge between the dentine horns, and the shape of the cervix. We also examined the manifestation of non-metric traits at the EDJ including the crista obliqua, cusp 5, and post-paracone tubercle. Furthermore, we report on additional morphological features including centrally placed dentine horn tips and twinned dentine horns. Our results indicate that EDJ morphology can discriminate with a high degree of reliability between Neanderthals and recent modern humans at every molar position, and discriminate between the earlier and the later Neanderthal samples at every molar position, except for the M3 in shape space. The cervix in isolation can also discriminate between Neanderthals and recent modern humans, except at the M3 in form space, and is effective at discriminating between the earlier and the later Neanderthal samples, except at the M2/M2 in form space. In addition to demonstrating the taxonomic valence of the EDJ, our analysis reveals unique manifestations of dental traits in Neanderthals and expanded levels of trait variation that have implications for trait definitions and scoring.

Frecuencia y variabilidad de la morfología dental de molares temporales y permanentes en un grupo de mestizos caucasoides de Popayán (Cauca, Colombia) / Frequency and variability of dental morphology of temporal and permanent molars in a group of Caucasoid mestizos from Popayán (Cauca, Colombia)

Objetivo: Determinar la frecuencia y variabilidad de la morfología dental en molares temporales y permanentes de un grupo de mestizos caucasoides de Popayán (Cauca, Colombia), con el fin de generar nuevos marcadores grupales que permitan comparar las diferentes poblaciones colombianas y mundiales a partir de nueve rasgos morfológicos dentales coronales (RMDC). Materiales y métodos: Estudio descriptivo transversal cuantitativo que determinó la frecuencia y variabilidad de nueve RMDC (cúspide de Carabelli, reducción del hipocono, metaconulo, patrón cuspídeo, número de cúspides, pliegue acodado, protostílido, cúspide 6 y cúspide 7) mediante la metodología ASUDAS en 101 individuos autoreconocidos como mestizos caucasoides (59 femeninos y 42 masculinos), con edades comprendidas entre los 10 y los 17 años. Resultados: Se identificaron frecuencias significativas de reducción del hipocono (89,9%), Patrón cuspídeo en Y (81,6%) y número de cúspides (92,7%); y bajas frecuencias de metacónulo (0,2%), protostílido (0,6%) y cúspide 6 (0,2%). No se encontró dimorfismo sexual y asimetría bilateral en los RMDC estudiados. Conclusiones: La muestra estudiada se caracteriza por presentar una morfología dental propia de poblaciones mestizas colombianas que se incluyen en el complejo dental caucasoide (cúspide Carabelli, reducción del hipocono y número de cúspides); sin embargo, debido a los procesos etnohistóricos de la región geográfica donde se ubican, presentan influencia de grupos indígenas (patrón cuspídeo) incluidos en el complejo dental mongoloide. Palabras clave: Antropología dental, morfología dental, dientes molares, rasgos morfológicos dentales coronales, mestizos caucasoides

Objective: To determine the frequency and variability of dental morphology in temporary and permanent molars of a group of Caucasoid mestizos from Popayán (Cauca, Colombia), in order to generate new group markers that allow comparing the different Colombian and world populations from nine coronal dental morphological features (NMDT). Materials and methods: quantitative, descriptive, cross-sectional study that determined the frequency and variability of nine NMDT (Carabelli trait, hypocone reduction, metaconule, cusp pattern, cusp number, defleckting wrinkle, protostilyd, cusp 6 and cusp 7) using the ASUDAS methodology In 101 self-described individuals as Caucasoid mestizos (59 females and 42 males), aged between 10 and 17 years. Results: Significant reduction frequencies of the hypoconus (89.9%), cusp pattern in Y (81.6%) and number of cusps (92.7%) were identified; And low frequencies of metacele (0.2%), protostilyd (0.6%) and cusp 6 (0.2%). No sexual dimorphism and bilateral asymmetry were found in the NMDT studied. Conclusions: The sample studied is characterized by a dental morphology characteristic of Colombian mestizo populations that are included in the Caucasoid dental complex (Carabelli cusp, reduction of the hipocono and number of cusps). However, due to the ethnohistorical processes of the geographic region where they are located, they are influenced by indigenous groups (cuspid expression) included in the mongoloid dental complex

Frequency and variability of dental morphology in deciduous and permanent dentition of a Nasa indigenous group in the municipality of Morales, Cauca, Colombia.

OBJECTIVES: To determine the frequency, variability, sexual dimorphism and bilateral symmetry of fourteen dental crown traits in the deciduous and permanent dentition of 60 dental models (35 women and 25 men) obtained from a native, indigenous group of Nasa school children of the Musse Ukue group in the municipality of Morales, Department of Cauca, Colombia. METHODS: This is a quantitative, descriptive, cross-sectional study that characterizes dental morphology by means of the systems for temporary dentition from Dahlberg (winging), and ASUDAS (crowding, reduction of hypocone, metaconule and cusp 6), Hanihara (central and lateral incisors in shovel-shape and cusp 7), Sciulli (double bit, layered fold protostylid, cusp pattern and cusp number) and Grine (Carabelli trait); and in permanent dentition from ASUDAS (Winging, crowding, central and lateral incisors in shovel-shape and double shovel-shape, Carabelli trait, hypocone reduction, metaconule, cusp pattern, cusp number, layered fold protostylid, cusp 6 and cusp 7). RESULTS: The most frequent dental crown features were the shovel-shaped form, grooved and fossa forms of the Carabelli trait, metaconule, cusp pattern Y6, layered fold, protostylid (point P) and cusp 6. Sexual dimorphism was not observed and there was bilateral symmetry in the expression of these features. CONCLUSIONS: The sample studied presented a great affinity with ethnic groups belonging to the Mongoloid Dental Complex due to the frequency (expression) and variability (gradation) of the tooth crown traits, upper incisors, the Carabelli trait, the protostylid, cusp 6 and cusp 7. The influence of the Caucasoide Dental Complex associated with ethno-historical processes cannot be ruled out.

OBJETIVOS: Determinar la frecuencia, la variabilidad, el dimorfismo sexual y la simetría bilateral de 14 Rasgos Morfológicos Dentales Coronales (RMDC) en dentición temporal y permanente de 60 modelos (35 mujeres y 25 hombres) obtenidos de un grupo de indígenas escolares Nasa del cabildo Musse Ukue del municipio de Morales, departamento del Cauca. MÉTODOS: Estudio descriptivo transversal cuantitativo que caracteriza la morfología dental mediante los sistemas en dentición temporal Dahlberg (winging), Asudas (crowding, reducción de hipocono, metacónulo y cúspide 6), Hanihara (incisivos centrales y laterales en pala y cúspide 7), Sciulli (doble pala, protostílido, pliegue acodado, patrón cuspídeo y número de cúspides) y Grine (cúspide de Carabelli); y en dentición permanente Asudas (Winging, crowding, incisivos centrales y laterales en pala, doble pala, cúspide de Carabelli, reducción del hipocono, metacónulo, patrón cuspídeo, número de cúspides, pliegue acodado, protostílido, cúspide 6 y cúspide 7). RESULTADOS: Los RMDC más frecuentes fueron la forma de pala, formas surco y fosa de la cúspide de Carabelli, metacónulo, patrón cuspídeo Y6, pliegue acodado, protostílido (punto P) y cúspide 6. No se observó dimorfismo sexual y hubo simetría bilateral en la expresión de los rasgos. CONCLUSIONES: La muestra estudiada presenta una alta afinidad con grupos étnicos pertenecientes al Complejo Dental Mongoloide debido a la frecuencia (expresión) y variabilidad (gradación) de los RMDC, incisivos en pala, la cúspide Carabelli, el Protostílido, la cúspide 6 y la cúspide 7; sin embargo, no se puede descartar influencia del Complejo Dental Caucasoide asociado con procesos etno-históricos.

Frequency and variability of dental morphology in deciduous and permanent dentition of a Nasa indigenous group in the municipality of Morales, Cauca, Colombia / Frecuencia y variabilidad de la morfología dental en dentición temporal y permanente de un grupo de indígenas Nasa del municipio de Morales (Cauca, Colombia)

Abstract Objectives: To determine the frequency, variability, sexual dimorphism and bilateral symmetry of fourteen dental crown traits in the deciduous and permanent dentition of 60 dental models (35 women and 25 men) obtained from a native, indigenous group of Nasa school children of the Musse Ukue group in the municipality of Morales, Department of Cauca, Colombia. Methods: This is a quantitative, descriptive, cross-sectional study that characterizes dental morphology by means of the systems for temporary dentition from Dahlberg (winging), and ASUDAS (crowding, reduction of hypocone, metaconule and cusp 6), Hanihara (central and lateral incisors in shovel-shape and cusp 7), Sciulli (double bit, layered fold protostylid, cusp pattern and cusp number) and Grine (Carabelli trait); and in permanent dentition from ASUDAS (Winging, crowding, central and lateral incisors in shovel-shape and double shovel-shape, Carabelli trait, hypocone reduction, metaconule, cusp pattern, cusp number, layered fold protostylid, cusp 6 and cusp 7). Results: The most frequent dental crown features were the shovel-shaped form, grooved and fossa forms of the Carabelli trait, metaconule, cusp pattern Y6, layered fold, protostylid (point P) and cusp 6. Sexual dimorphism was not observed and there was bilateral symmetry in the expression of these features. Conclusions: The sample studied presented a great affinity with ethnic groups belonging to the Mongoloid Dental Complex due to the frequency (expression) and variability (gradation) of the tooth crown traits, upper incisors, the Carabelli trait, the protostylid, cusp 6 and cusp 7. The influence of the Caucasoide Dental Complex associated with ethno-historical processes cannot be ruled out.

Resumen Objetivos: Determinar la frecuencia, la variabilidad, el dimorfismo sexual y la simetría bilateral de 14 Rasgos Morfológicos Dentales Coronales (RMDC) en dentición temporal y permanente de 60 modelos (35 mujeres y 25 hombres) obtenidos de un grupo de indígenas escolares Nasa del cabildo Musse Ukue del municipio de Morales, departamento del Cauca. Métodos: Estudio descriptivo transversal cuantitativo que caracteriza la morfología dental mediante los sistemas en dentición temporal Dahlberg (winging), Asudas (crowding, reducción de hipocono, metacónulo y cúspide 6), Hanihara (incisivos centrales y laterales en pala y cúspide 7), Sciulli (doble pala, protostílido, pliegue acodado, patrón cuspídeo y número de cúspides) y Grine (cúspide de Carabelli); y en dentición permanente Asudas (Winging, crowding, incisivos centrales y laterales en pala, doble pala, cúspide de Carabelli, reducción del hipocono, metacónulo, patrón cuspídeo, número de cúspides, pliegue acodado, protostílido, cúspide 6 y cúspide 7). Resultados: Los RMDC más frecuentes fueron la forma de pala, formas surco y fosa de la cúspide de Carabelli, metacónulo, patrón cuspídeo Y6, pliegue acodado, protostílido (punto P) y cúspide 6. No se observó dimorfismo sexual y hubo simetría bilateral en la expresión de los rasgos. Conclusiones: La muestra estudiada presenta una alta afinidad con grupos étnicos pertenecientes al Complejo Dental Mongoloide debido a la frecuencia (expresión) y variabilidad (gradación) de los RMDC, incisivos en pala, la cúspide Carabelli, el Protostílido, la cúspide 6 y la cúspide 7; sin embargo, no se puede descartar influencia del Complejo Dental Caucasoide asociado con procesos etno-históricos.

Correlación de diez rasgos morfológicos dentales coronales entre molares deciduos y permanentes en tres grupos étnicos colombianos / Correlation of ten non-metric dental traits between deciduous and permanent molars of three ethnic colombian groups

Objetivos: Determinar la correlación de diez Rasgos Morfológicos Dentales Coronales RMDC (Carabelli, hipocono, puente de esmalte, metacónulo, protostílido, pliegue acodado, patrón cuspídeo, numero de cúspides y cúspide 6 y 7) entre los segundos molares deciduos superiores (um2) e inferiores (lm2), los primeros molares permanentes superiores (UM1) e inferiores (LM1) y los segundos molares permanentes superiores (UM2) e inferiores (LM2). Materiales y métodos: Este es un estudio descriptivo transversal para determinar la correlación de diez RMDC mediante su frecuencia y variabilidad, observados en 201 modelos de yeso de mestizos caucasoides de Cali, 84 modelos de yeso de afrocolombianos de Puerto Tejada y 60 modelos de yeso de indígenas del Amazonas. Resultados: Los indígenas del Amazonas entre um2/UM1 presentan correlación alta en Carabelli y número de cúspides; y muy alta en metacónulo y patrón cuspídeo. Los mestizos caucasoides entre um2/UM1 moderada en Carabelli, pliegue acodado y patrón cuspídeo; y alta en cúspide 6; y entre UM1/UM2/LM1/LM2 moderada en pliegue acodado, y alta en protostílido, patrón cuspídeo y cúspide 6. Los afrocolombianos entre UM1/UM2/LM1/LM2 moderada en pliegue acodado; y alta en protostílido, patrón cuspídeo y cúspide 6. Conclusiones: Los hallazgos soportan lo propuesto por la teoría de los campos morfogenéticos, la cual manifiesta que el diente gradiente de los molares deciduos y permanentes es um2/lm2, dado que retiene la configuración básica del patrón de contacto y el número de cúspides, Por tanto UM1/UM2/LM1/LM2 variarán de acuerdo al origen étnico y a la influencia ambiental de cada una de los tres grupos estudiados.

Aim: To determine correlations of ten non-metric dental crown traits NMDCT (Carabelli, hipocon2, enamel bridge, metaconule, protostylid, deflecting wrinkle, pattern cusp, cusp number and 6 and 7 cusp) between deciduous second upper (um2) and low (lm2) molars, permanent first upper (UM1) and lower (LM1) molars and permanent second upper (UM2) and lower (LM2) molars were studied. Materials y methods: This descriptive study determines the correlation of ten NMDCT through of the frequency and variability, observed on 201 dental casts of Cali racially mixed population, 84 dental casts of Puerto Tejada African-Colombian population and 60 dental casts of Colombian Amazons natives. Results: The Colombian Amazon natives showed high correlation in Carabelli and cusp number between um2/UM1; and very high in metaconule and pattern cusp. Cali racially mixed population showed moderated correlation in Carabelli, deflecting wrinkle and pattern cusp between um2/UM1; and high in 6 cusp. And between UM1/UM2/LM1/LM2 moderate in deflecting wrinkle; and high in protostylid, pattern cusp and 6 cusp. Puerto Tejada African-Colombian population showed moderated correlation between UM1/UM2/LM1/LM2 in deflecting wrinkle; and high in protostylid, pattern cusp and 6 cusp. Conclusions: Findings support the proposal of morphogenetic field theory, which exposes that the key tooth in deciduous and permanent molars is um2/lm2 because it retains the basic configuration of contact and number of cusps pattern, so UM1/UM2/LM1/LM2 will vary according to ethnic origin and to the environmental influence of each of three studied ethnic groups.

Restauraciones preventivas en resina como estrategia para control de la morfología dental / Preventive resin restorations as a strategy to control dental morphology

La morfología dental constituye uno de los agentes multicausales que contribuyen al desarrollo de la caries, en virtud a su capacidad de retener la placa dental y dificultar su remoción mediante las técnicas convencionales de higiene bucal. Bajo el enfoque preventivo de la odontología actual, los agentes selladores de resina han demostrado ser una herramienta eficaz que modifica el comportamiento de los rasgos morfológicos que configuran fosas y fisuras, por lo que su empleo dentro de los programas de promoción y prevención en salud bucal es masivo. No obstante el éxito clínico, aún existen fallas diagnósticas de odontólogos y auxiliares de higiene bucal, quienes no evalúan durante el diligenciamiento de la historia clínica el modo como se comporta la morfología dental, siendo esta altamente variable en cada uno de los individuos. En la presente revisión de literatura, dentro de los conceptos de la antropología dental, se describen los rasgos morfológicos dentales cuya expresión y variabilidad influyen en la retención de la placa dental, y se hace referencia a la eficacia de las restauraciones preventivas en resina en el control de la morfología dental como agente retenedor de placa dental

Dental morphology is one of multiple causative factors contributing to caries development, as it can be a dental plaque retention factor and it may difficult oral hygiene techniques. Under the preventive approach of actual dentistry, dental sealants have showed to be an effective tool to modify the retention characteristics of pits and fissures, and their use in promotion and prevention programs in oral health is massive. Despite clinical success of sealants application, there are still errors in diagnosis and lack of knowledge about dental morphology, which is highly variable among individuals. In this literature review are presented morphologic dental characteristics within the concepts of dental anthropology, describing their expression and variability as factors that influence dental plaque retention, and the role of preventive resin restorations in the control of dental morphology traits is also described