scholarly journals Hypodontia: An Update on Its Etiology, Classification, and Clinical Management

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Azza Husam Al-Ani ◽  
Joseph Safwat Antoun ◽  
William Murray Thomson ◽  
Tony Raymond Merriman ◽  
Mauro Farella
Keyword(s):  
Genetic Factors ◽  
Treatment Time ◽  
Tooth Agenesis ◽  
Third Molars ◽  
Prevention Strategies ◽  
Genetic Syndrome ◽  
Novel Treatments ◽  
Clinical Challenge ◽  
Craniofacial Malformation ◽  
Genetic And Environmental Factors

Hypodontia, or tooth agenesis, is the most prevalent craniofacial malformation in humans. It may occur as part of a recognised genetic syndrome or as a nonsyndromic isolated trait. Excluding third molars, the reported prevalence of hypodontia ranges from 1.6 to 6.9%, depending on the population studied. Most affected individuals lack only one or two teeth, with permanent second premolars and upper lateral incisors the most likely to be missing. Both environmental and genetic factors are involved in the aetiology of hypodontia, with the latter playing a more significant role. Hypodontia individuals often present a significant clinical challenge for orthodontists because, in a number of cases, the treatment time is prolonged and the treatment outcome may be compromised. Hence, the identification of genetic and environmental factors may be particularly useful in the early prediction of this condition and the development of prevention strategies and novel treatments in the future.

The molecular basis of non-syndromic orofacial clefts and tooth agenesis

2018 ◽  
Vol 86 (4) ◽  
pp. 321
Author(s):  
Agnieszka Danuta Gaczkowska ◽  
Paweł Piotr Jagodziński ◽  
Adrianna Mostowska
Keyword(s):  
Genetic Factors ◽  
Tooth Agenesis ◽  
Chromosomal Locus ◽  
Orofacial Clefts ◽  
Factors Influencing ◽  
Polymorphic Variants ◽  
Methodological Approaches ◽  
Genetic And Environmental Factors ◽  
European Populations

Non-syndromic orofacial clefts and tooth agenesis are two of the most common craniofacial birth defects. Both of them have a complex etiology, with genetic and environmental factors involved. Additionally, the epigenetic modifications have been implicated in the pathogenesis of these structural malformations. Despite an increasing number of research studies, using a variety of methodological approaches, the role of genetic factors in the etiology of orofacial clefts and tooth agenesis is still not well elucidated. The most consistent findings across studies concerning the genetic factors influencing the risk to orofacial clefts include the association of polymorphic variants of the IRF6 gene and the chromosomal locus 8q24.21. The major candidate gene for tooth agenesis in the European populations is WNT10A; its pathogenic mutations are present in more than 50% of patients with this dental anomaly. It has been found that both orofacial clefts and tooth agenesis, which co-occurrence is often reported, may share common candidate genes.

scholarly journals HYPODONTIA WITH CLASS I MALLOCLUSION AND MAXILLARY DIASTEMA

2018 ◽  
Vol 1 (2) ◽  
pp. 98
Author(s):  
Bunga Fatimah ◽  
I Gusti Aju Wahju Ardani
Keyword(s):  
Case Management ◽  
Class I ◽  
Tooth Agenesis ◽  
Third Molars ◽  
Missing Teeth ◽  
Facial Aesthetics ◽  
The Third ◽  
Congenitally Missing Teeth ◽  
Congenitally Missing ◽  
Severe Type

Background: Dental agenesis is a term that refers to the absence of one or more teeth, and hypodontia refers to a severe type of tooth agenesis involving less than six or more than one congenitally missing teeth, excluding the third molars. Purpose: This aimed to report the correction of overbite by using intrusion archwires. Case: A 20-year-old female patient had class I malocclusion and deep overbite, incisor retroclination, mild mandibular crowding and agenesis of 12, 13, 14, 15, and 24. Case management: The case was treated with non-extraction using 0.022 pre-adjusted technique to level and unravel using intrusion archwires to correct the deep overbite. Conclusion: The 17-month treatment resulted in a corrected overbite, good occlusion, and good facial aesthetics.

Defining Subphenotypes for Tooth Agenesis: Does Side Matter?

2009 ◽  
Vol 34 (2) ◽  
pp. 169-172 ◽  
Author(s):  
Marcelo de Castro Costa ◽  
Erika Calvano Küchler ◽  
Paulo Ferreira Garcia Filho ◽  
Adriana Modesto ◽  
Alexandre Rezende Vieira
Keyword(s):  
Genetic Factors ◽  
Large Cohort ◽  
Differentially Expressed ◽  
Tooth Agenesis ◽  
Panoramic Radiographs ◽  
Mandibular Arch ◽  
Specific Hypothesis ◽  
Study Population ◽  
The Right

Objectives: The etiology of tooth agenesis is still poorly understood. The identification of sub-populations with specific types of hypodontia (subphenotypes) would allow testing the specific hypothesis that certain genetic factors contribute to the specific subphenotype. The aim of this work was assessing a large cohort to verify if preferential tooth agenesis subphenotypes could be identified. Method: Panoramic radiographs of 1052 cases were examined and 1034 were used in this study. The presence of tooth agenesis was assessed in the study population. Results: The frequency of tooth agenesis in the studied population was 3.77%. While bilateral cases did not differ in the frequency of agenesis by arch (p = 0.8), unilateral cases presented more commonly agenesis on the mandibular arch (p = 0.03). This result was clearly driven by the frequency of second premolar agenesis, which was the most common absent tooth in the studied population. Unilateral lower second premolar agenesis was found more often than bilateral agenesis (p = 0.047). Conclusions:Our findings that unilateral lower second premolar agenesis is more common than bilateral agenesis, with a trend for unilateral agenesis being more common on the right side may suggest specific genetic factors may be differentially expressed depending on the side.

scholarly journals interactions between genetic and environmental factors determine direction of population lateralization

2005 ◽  
Vol 28 (4) ◽  
pp. 598-598 ◽  
Author(s):  
chao deng
Keyword(s):  
Environmental Factors ◽  
Genetic Factors ◽  
Head Rotation ◽  
Head Turning ◽  
Genetic And Environmental Factors ◽  
Genetically Determined

direction of the embyro's head rotation is determined by asymmetrical expression of several genes (such as shh, nodal, lefty, and fgf8) in hensen's node. this genetically determined head-turning bias provides a base for light-aligned population lateralization in chicks, in which the direction of the lateralization is determined by genetic factors and the degree of the lateralization is determined by environmental factors.

Muscle Dissatisfaction and Muscle-Enhancing Substance Use: A Population-Based Twin Study in Young Adult Men

2006 ◽  
Vol 9 (3) ◽  
pp. 431-437 ◽  
Author(s):  
Anu Raevuori ◽  
Anna Keski-Rahkonen ◽  
Richard J. Rose ◽  
Aila Rissanen ◽  
Jaakko Kaprio
Keyword(s):  
Substance Use ◽  
Environmental Factors ◽  
Twin Study ◽  
Genetic Factors ◽  
Population Based ◽  
Tetrachoric Correlation ◽  
Polychoric Correlation ◽  
Adult Men ◽  
Genetic And Environmental Factors ◽  
Best Fit

AbstractIn the population-based FinnTwin16 study, proportions of genetic and environmental factors contributing to muscle dissatisfaction and muscle-enhancing substance use were assessed in 319 pairs of twin brothers: 141 monozygotic (MZ) and 178 dizygotic (DZ) pairs. In addition there were 86 twin individuals from pairs in which only one co-twin responded. Of all respondents, 30% experienced high muscle dissatisfaction. The corresponding proportion of muscle-enhancing substance use was 10%. The subjects were similar in age (23.8 years, 95% confidence interval [CI] 23.76–23.84), body mass index (23.7, 95% CI 23.5–23.9), and waist circumference (84.5 cm, 95% CI 83.7–85.2), independent of their muscle dissatisfaction or muscle-enhancing substance use status and independent of their zygosity. The MZ polychoric correlation for muscle dissatisfaction was .39 (95% CI .17–.58) and .27 for DZ pairs (95% CI .07–.46). The MZ tetrachoric correlation for muscle-enhancing substance use was .65 (95% CI .28–.87) and .56 for DZ pairs (95% CI .26–.78). The AE model, where additive genetic factors (A) accounted for 42% (95% CI .23–.59) and unique environmental factors (E) 58% (95% CI .41–.77) of the liability, provided the best fit for muscle dissatisfaction. The CE model, where common environmental factors (C) accounted for 60% (95% CI .37–.77) and unique environmental factors (E) 40% (95% CI .23–.63) of the liability, provided the best fit for muscle-enhancing substance use. Both genetic and unique (nonfamilial) environmental factors are involved in muscle dissatisfaction in the population. Nongenetic factors (both familial and non-familial) appear to best explain the use of muscle-enhancing substances.

scholarly journals Environmental and Genetic Contributions to Indicators of Oral Malodor in Twins

2011 ◽  
Vol 14 (6) ◽  
pp. 568-572 ◽  
Author(s):  
Walter A. Bretz ◽  
Aaron Biesbrock ◽  
Patricia M. Corby ◽  
Andrea L. Corby ◽  
Walter G. Bretz ◽  
...  
Keyword(s):  
Environmental Factors ◽  
Genetic Factors ◽  
Sulfur Compounds ◽  
Exhaled Breath ◽  
Tongue Coating ◽  
Oral Malodor ◽  
Volatile Sulfur Compounds ◽  
Item Questionnaire ◽  
Genetic And Environmental Factors ◽  
Genetic Contributions

This study aimed to: (1) determine concordance rates of self-reported and subjectively determined indicators of oral malodor in twins; (2) determine the relative contributions of genetic and environmental factors to levels of volatile sulfur compounds (VSCs) in intraoral and exhaled breath. Fifty-one twin pairs participated in the study. Measurements of VSCs were obtained by a halimeter. The presence of tongue coatings was determined and twins filled out a 32-item questionnaire on oral malodor indicators independently of one another. Estimates of heritability (h2) for halimeter measurements were computed by SOLAR. The concordance rates for the presence of tongue coating among identical and fraternal twins were 67% and 11%, respectively. In the 10 most informative items, 70% exhibited higher concordance rates for identical than for fraternal twins. Of particular interest were the differences in concordance rates for dry mouth, sinus infection and unusual sweating. The h2 for intra-oral breath was 0.28 ± 0.17 (NS), whereas the h2 for exhaled breath was 0.50 ± 0.20 (p = .0207). The concordance rates of tongue coatings and malodor indicators were higher in identical twins than in fraternal twins. Intraoral breath VSC values were primarily attributable to environmental factors, whereas exhaled breath VSC values were partially explained by genetic factors.

scholarly journals Changes in genetic and environmental influences on depressive symptoms across adolescence and young adulthood

2006 ◽  
Vol 189 (5) ◽  
pp. 422-427 ◽  
Author(s):  
Jennifer Y. F. Lau ◽  
Thalia C. Eley
Keyword(s):  
Depressive Symptoms ◽  
Young Adulthood ◽  
Genetic Factors ◽  
Environmental Influences ◽  
Sibling Pairs ◽  
Time Points ◽  
Age Related ◽  
Adolescence And Young Adulthood ◽  
Genetic And Environmental Factors ◽  
Time Point

BackgroundDepression rises markedly in adolescence, a time when increased and new genetic influences have been reported.AimsTo examine ‘new’ and ‘stable’ genetic and environmental factors on depressive symptoms in adolescence and young adulthood.MethodA questionnaire survey investigated a sample of twin and sibling pairs at three time points over an approximately 3-year period. Over 1800 twin and sibling pairs reported depressive symptoms at the three time points. Data were analysed using multivariate genetic models.ResultsDepressive symptoms at all time points were moderately heritable with substantial non-shared environmental contributions. Wave I genetic factors accounted for continuity of symptoms at waves 2 and 3. ‘New’ genetic effects at wave 2 also influenced wave 3 symptoms. New non-shared environmental influences emerged at each time point.ConclusionsNew genetic and environmental influences may explain age-related increases in depression across development.

scholarly journals A Genetic Analysis of Coffee Consumption in a Sample of Dutch Twins

2009 ◽  
Vol 12 (2) ◽  
pp. 127-131 ◽  
Author(s):  
Jaqueline M. Vink ◽  
Annemieke S. Staphorsius ◽  
Dorret I. Boomsma
Keyword(s):  
Environmental Factors ◽  
Genetic Factors ◽  
Model Fitting ◽  
Coffee Consumption ◽  
Genetic Influences ◽  
Psychoactive Substance ◽  
Twin Registry ◽  
Genetic And Environmental Factors ◽  
Dutch Twins ◽  
Twin Resemblance

AbstractCaffeine is by far the most commonly used psychoactive substance. Caffeine is consumed regularly as an ingredient of coffee. Coffee consumption and coffee preference was explored in a sample of 4,495 twins (including 1,231 pairs) registered with the Netherlands Twin Registry. Twin resemblance was assessed by tetrachoric correlations and the influence of both genetic and environmental factors was explored with model fitting analysis in MX. Results showed moderate genetic influences (39%) on coffee consumption. The remaining variance was explained by shared environmental factors (21%) and unique environmental factors (40%). The variance in coffee preference (defined as the proportion of coffee consumption relative to the consumption of coffee and tea in total) was explained by genetic factors (62%) and unique environmental factors (38%).

scholarly journals Pentingnya Gen dalam Membentuk Kepribadian Anak

2019 ◽  
Vol 2 (2) ◽  
pp. 44-64
Author(s):  
Zuyyina Candra Kirana
Keyword(s):  
Environmental Factors ◽  
Personal Development ◽  
Genetic Factors ◽  
Developmental Process ◽  
Personality Development ◽  
Human Beings ◽  
Two Factors ◽  
Genetic And Environmental Factors

Man was born according to his fitrah. The phylogenetic theory contains the innate, both genetically and other innate, but this is not an absolute being, but also in the developmental process that influences it. Islam also looks at genetic and environmental factors in relation to personality formation. Human beings and all the growth and characteristics are the embodiment of two factors, namely genetic factors (hereditary) and the environment. This paper is intended to enlighten that in the perspective of Islamic genetics and environment both play an important role for personality development. Because one's personal development is a result of the interaction of genetics and environment.

scholarly journals Sequence analysis of candidate genes in two Roma families with severe tooth agenesis

Genetika ◽  
2016 ◽  
Vol 48 (3) ◽  
pp. 945-954
Author(s):  
Dana Gabriková ◽  
Daniela Grejtáková ◽  
Jarmila Bernasovská ◽  
Anna Pavúková ◽  
Barbora Lewandowská ◽  
...  
Keyword(s):  
Sequence Analysis ◽  
Family Members ◽  
Tooth Agenesis ◽  
Sequence Variants ◽  
Third Molars ◽  
Missing Teeth ◽  
Coding Regions ◽  
Large Families ◽  
Variable Phenotype ◽  
Systemic Condition

Selective tooth agenesis is the most common congenital disorder affecting the formation of dentition in humans. Both its forms (hypodontia and more severe oligodontia) can be found either in isolated form and they can be associated with systemic condition (syndromic tooth agenesis). In addition to previously known genes (PAX9, MSX1 and AXIN2) mutations in EDA, EDARADD and WNT10 gene were recently found to be involved in isolated forms of tooth agenesis. The objective of this study was to characterize the phenotype of affected members in two large families of Roma origin segregating severe isolated tooth agenesis with very variable phenotype and to perform mutation analysis of seven genes with aim to find causal mutation. 26 family members were clinically examined and coding regions of seven genes (MSX1, PAX9, AXIN2, EDA, EDAR, EDARADD and WNT10A) were sequenced. With exclusion of third molars, average number of missing teeth was 8.2 ? 4.9 in family 1 and 7.1 ? 2.3 in family 2. The most frequently missing teeth were maxillary lateral incisors and first premolars and mandibular central incisors. Sequencing revealed four potentially damaging variants (g.Ala40Gly in MSX1, g.Ala240Pro in PAX9, g.Pro50Ser in AXIN2 and g.Met9Ile in EDARADD); however, none of them was present in all affected family members. Variable phenotype in both families examined in this study is in favour of heterogeneous genetic cause of tooth agenesis in these families: possible interaction of several defected genes, sequence variants in regulatory regions and additional environmental factors is assumed.

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