Root Lengths in 47,XYY Males’ Permanent Teeth

Studies on individuals with sex chromosome anomalies have demonstrated the promoting effect of the Y chromosome on tooth crown enamel and dentin growth. The present research investigated permanent tooth root lengths in 47,XYY males. The measurements were made from panoramic radiographs. The results indicate longer tooth roots in 47,XYY males compared with those in control males and females. The promoting effect of the Y chromosome on dental growth thus continues in the form of root dentin after the completion of crown growth. The results, together with those on tooth crown sizes in 47,XYY males, suggest that growth excesses are evident and final, beginning a few months after birth and continuing up to the age of 14 years, at least. The excess root dentin growth in 47,XYY males, as well as sexual dimorphism in the growth of crown and root dentin, might be caused by the same factor on the Y chromosome.

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MINERALIZATION OF TEETH ENAMEL AFTER ERUPTION

Wiadomości Lekarskie ◽

10.36740/wlek202106101 ◽

2021 ◽

Vol 74 (6) ◽

pp. 1297-1301

Author(s):

Oleksij P. Kostyrenko ◽

Nataliia I. Vynnyk ◽

Mykhailo M. Koptev ◽

Petro A. Hasiuk ◽

Maksym I. Skrypnyk ◽

...

Keyword(s):

Light And Electron Microscopy ◽

Permanent Tooth ◽

Postnatal Period ◽

Permanent Teeth ◽

Tooth Crown ◽

Electron Microscopic ◽

Cervical Portion ◽

Immunohistochemical Methods ◽

Protein Deposit ◽

Different Parts

The aim: The paper was aimed at the study of the processes of mineralization of the enamel of the permanent tooth after its eruption. Materials and methods: To study the structure of the enamel of permanent teeth has been carried out using light and electron microscopy. The study of the process of the development of the primordia of the permanent teeth involved 10 culled puppies of 30-40 days of age. Microscopic, electron microscopic, immunohistochemical methods of research have been used to study the processes of histogenesis. Results: The studies show that in the postnatal period, the formation of the crown, externally covered with cuticular epithelium, marks the formation of the primordium of the permanent tooth at the follicle stage. After eruption of a tooth, different parts of its crown have three individual structural and functional barriers to enamel biomineralization. The first one is provided by the cuticular epithelium of the pitted areas of the crown, which ensures filtering of the salivary fluid from the protein deposit in the form of a pellicle. The second barrier is defined on the lateral and cuspidate surfaces of the enamel, where the cuticle is erased or poorly expressed. The third structural and functional barrier of enamel biomineralization is located in the cervical portion of teeth of different classes. Conclusions: Different areas of the enamel in the tooth crown have specific filtration barriers, which can be distinguished as follows: pit-and-fissure-and-groove, cuspidateand-approximal, and cervical barriers. The cuticle is poorly expressed or totally absent on the cusps of the tooth crowns in contrast to pitted areas.

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Morphological Variations of the Cemento-Enamel Junction in Permanent Dentition / Morfološke varijacije cementno gleđnog spoja kod zuba stalne denticije

Acta Facultatis Medicae Naissensis ◽

10.1515/afmnai-2015-0021 ◽

2015 ◽

Vol 32 (3) ◽

pp. 209-214 ◽

Cited By ~ 1

Author(s):

Nenad Stošić ◽

Stefan Dačić ◽

Dragica Dačić Simonović

Keyword(s):

Room Temperature ◽

Contact Point ◽

Morphological Diversity ◽

Permanent Teeth ◽

Tooth Crown ◽

Running Water ◽

Morphological Variations ◽

Different Types ◽

Root Dentin ◽

The Relationship

Abstract Cemento-enamel junction (CEJ) is an important anatomical structure of the tooth, which is located in the cervical part of the tooth between the crown and root, or at the contact point between the enamel which overlaps the tooth crown and cementum overlapping the root dentin. There are four possible relationships between two tissues that make the CEJ such as: the cement overlaps the enamel; the enamel overlaps the cement; the enamel and cement abut each other with no overlap; the enamel and cement are not in contact. The aim of this study was to determine the relationship between the enamel and cement which make the CEJ in different types of permanent teeth. The material consisted of 30 permanent teeth with intact CEJ. Staining of CEJ was carried out using the methylene blue. After staining, the tooth was washed under the running water and drying at room temperature. Each tooth was longitudinally cut in the vestibular-oral direction. Observation of CEJ was done with Leica light microscope and images were obtained using a Nikon camera. The results indicated that the most common form of CEJ between the cement and enamel in the region of CEJ was that cement and enamel abutted without overlap (36.7%), followed by the cement overlapping the enamel (33.3%), and the cases when a gap between the cement and enamel (16.7%) was present, and when the enamel overlaped the cement (13.3%). Because of the morphological diversity of CEJ, careful performing of dental interventions in the region of tooth neck is necessary because they may change the morphology of this region, induce the pathological processes and hypersensitivity of teeth.

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Evaluation of tooth number anomalies in a subpopulation of the North-East of Turkey

European Journal of Dentistry ◽

10.4103/1305-7456.137641 ◽

2014 ◽

Vol 08 (03) ◽

pp. 337-341 ◽

Cited By ~ 6

Author(s):

Muhammet Karadas ◽

Mevlut Celikoglu ◽

Mustafa Sadik Akdag

Keyword(s):

Permanent Tooth ◽

Permanent Teeth ◽

Missing Teeth ◽

Panoramic Radiographs ◽

Dental Patients ◽

North East ◽

The North ◽

Significant Difference ◽

Chi Squared ◽

Tooth Number

ABSTRACT Objective: The aim was to evaluate the prevalence and distribution of tooth number anomalies in a Turkish subpopulation. Materials and Methods: A population of 2722 patients (1532 females and 1190 males; mean age, 12.33 ± 2.5 years) was retrospectively examined to determine the prevalence and distribution of the hypodontia, oligodontia, and hyperdontia using panoramic radiographs. All permanent teeth were investigated except thirds molars and the data obtained were recorded as unilateral (left or right) or bilateral according to gender. Pearson's Chi-squared and Fisher exact tests were used for difference comparisons (P < 0.05). Results: Permanent tooth anomalies were found in at least 132 (4.84%) of 2722 patients with no statistically difference between the genders, consists of 4.63% females and 5.12% males. Distribution of hyperdontia was statistically significant difference between genders, whereas distribution of hypodontia and oligodontia was no significant difference between genders. Hypodontia was the most frequently observed anomaly (3.67%), followed by hyperdontia (0.96%), and oligodontia (0.21%). Oligodontia and hypodontia were more frequent in females (3.98% and 0.26%, respectively), whereas hyperdontia was more frequently observed in males (1.68%). Maxillary lateral incisors were most common missing teeth (2.27%), while the frequency of hyperdontia was most common in premolars. Conclusion: The prevalence of teeth number anomalies was 4.84% of dental patients. Maxillary lateral incisors were most common missing teeth, while the frequency of hyperdontia was most common in premolars.

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MEIOSIS IN MALE DROSOPHILA MELANOGASTER I. ISOLATION AND CHARACTERIZATION OF MEIOTIC MUTANTS AFFECTING SECOND CHROMOSOME DISJUNCTION

Genetics ◽

10.1093/genetics/78.4.1127 ◽

1974 ◽

Vol 78 (4) ◽

pp. 1127-1142

Author(s):

Richard C Gethmann

Keyword(s):

Y Chromosome ◽

Sex Chromosomes ◽

Sex Chromosome ◽

Chromosome Loss ◽

Meiotic Mutants ◽

Isolation And Characterization ◽

Males And Females ◽

Chromosome Nondisjunction ◽

Chromosome Disjunction

ABSTRACT Two second chromosome, EMS-induced, meiotic mutants which cause an increase in second chromosome nondisjunction are described. The first mutant is recessive and causes an increase in second chromosome nondisjunction in both males and females. It causes no increase in nondisjunction of the sex chromosomes in either sex, nor of the third chromosome in females. No haplo-4-progeny were recovered from either sex. Thus, it appears that this mutant, which is localized to the second chromosome, affects only second chromosome disjunction and acts in both sexes.—The other mutant affects chromosome disjunction in males and has no effect in females. Nondisjunction occurs at the first meiotic division. Sex chromosome disjunction in the presence of this mutant is similar to that of sc4sc8, with an excess of X and nullo-XY sperm relative to Y and XY sperm. In some lines, there is an excess of nullo-2 sperm relative to diplo-2 sperm, which appears to be regulated, in part, by the Y chromosome. A normal Y chromosome causes an increase in nullo-2 sperm, where BsY does not. There is also a high correlation between second and sex chromosome nondisjunction. Nearly half of the second chromosome exceptions are also nondisjunctional for the sex chromosomes. Among the double exceptions, there is an excess of XY nullo-2 and nullo-XY diplo-2 gametes. Meiotic drive, chromosome loss and nonhomologous pairing are considered as possible explanations for the double exceptions.

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The Drosophila Y chromosome affects heterochromatin integrity genome-wide

10.1101/156000 ◽

2017 ◽

Cited By ~ 5

Author(s):

Emily J. Brown ◽

Alison H. Nguyen ◽

Doris Bachtrog

Keyword(s):

Y Chromosome ◽

Sex Chromosome ◽

Gene Activation ◽

Chromatin Modifications ◽

Active Chromatin ◽

Genomic Distribution ◽

Sexual Dimorphisms ◽

Y Chromosomes ◽

Genome Wide ◽

Males And Females

AbstractThe Drosophila Y-chromosome is gene poor and mainly consists of silenced, repetitive DNA. Nonetheless, the Y influences expression of hundreds of genes genome-wide, possibly by sequestering key components of the heterochromatin machinery away from other positions in the genome. To test the influence of the Y chromosome on the genome-wide chromatin landscape, we assayed the genomic distribution of histone modifications associated with gene activation (H3K4me3), or heterochromatin (H3K9me2 and H3K9me3) in fruit flies with varying sex chromosome complements (X0, XY and XYY males; XX and XXY females). Consistent with the general deficiency of active chromatin modifications on the Y, we find that Y gene dose has little influence on the genomic distribution of H3K4me3. In contrast, both the presence and the number of Y-chromosomes strongly influence genome-wide enrichment patterns of repressive chromatin modifications. Highly repetitive regions such as the pericentromeres, the dot, and the Y chromosome (if present) are enriched for heterochromatic modifications in wildtype males and females, and even more strongly in X0 flies. In contrast, the additional Y chromosome in XYY males and XXY females diminishes the heterochromatic signal in these normally silenced, repeat-rich regions, which is accompanied by an increase in expression of Y-linked repeats. We find hundreds of genes that are expressed differentially between individuals with aberrant sex chromosome karyotypes, many of which also show sex-biased expression in wildtype Drosophila. Thus, Y-chromosomes influence heterochromatin integrity genome-wide, and differences in the chromatin landscape of males and females may also contribute to sex-biased gene expression and sexual dimorphisms.

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A fool’s mission? A test of three common assumptions in dental metric analyses

Dental Anthropology Journal ◽

10.26575/daj.v26i3.48 ◽

2018 ◽

Vol 26 (3) ◽

pp. 16-30 ◽

Cited By ~ 2

Author(s):

Brian E. Hemphill

Keyword(s):

Permanent Tooth ◽

Permanent Dentition ◽

Permanent Teeth ◽

Human Populations ◽

Tooth Size ◽

Sex Dimorphism ◽

Unit Of Analysis ◽

Environmental Perturbations ◽

Tooth Type ◽

Males And Females

Three aspects of metric variation in the permanent dentition of humans are often simply accepted as true. The first is that formation of the permanent dentition occurs within morphogenetic fields broadly associated with tooth type and jaw. The second is that dental development of among females is characterized by a higher degree of ontogenetic buffering relative to males. The third is that expression of sex dimorphism in permanent tooth size is expressed uniformly among well-nourished human populations. This study tests these assumptions through an examination of mesiodistal and buccolingual dimensions of all non-canine permanent teeth, except third molars, among 2,709 living individuals of 15 ethnic groups from South Asia. With sexes pooled, only one in four contrasts of variance among key versus distal teeth within dental fields are significantly heterogeneous, while one in four contrasts yield higher levels of variance among key teeth relative to their distal counterparts within a dental field. Such results weaken considerably orthodox applications of Butler’s dental field theory. When samples are the unit of analysis, male samples are marked by fewer dental fields with significantly heterogeneous levels of variance between key and distal members, while males and females are affected equally by significantly heterogeneous variation between key and distal members when dental fields are the unit of analysis. Such results suggest males and females are equally buffered against environmental perturbations that affect odontometric variation. One-way ANOVA indicates that a tooth’s position within a dental field ac-counts for 15.5% to 23.1% of the observed varia-tion in tooth size, while two-way ANOVA reveals that when sex is added as a second factor, the percentage of variance in tooth size explained increases from 16.7% to 30.8%, an improvement of 27.2%. Such results indicate sex dimorphism in tooth size varies in both patterning and in magnitude among these samples, thereby explaining why discriminant functions developed for one population often perform more poorly when applied to other populations.

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Sex-chromosome Mosaicism in the Lemur-like Possum Hemibelideus lemuroides (Marsupialia: Petauridae)

Australian Journal of Biological Sciences ◽

10.1071/bi9840131 ◽

1984 ◽

Vol 37 (3) ◽

pp. 131 ◽

Cited By ~ 1

Author(s):

GM McKay ◽

LR McQuade ◽

JD Murray ◽

SR von Sturmer

Keyword(s):

Bone Marrow ◽

Y Chromosome ◽

Sex Chromosome ◽

Bone Marrow Cells ◽

Regular System ◽

Somatic Tissue ◽

Fibroblast Cells ◽

X Chromosomes ◽

Chromosome Mosaicism ◽

Males And Females

A regular system of sex chromosome mosaicism in a somatic tissue is reported in H. lemuroides. Spermatogonial mitosis and cultured fibroblast cells are 2n = 20, while most bone marrow cells from both males and females are 2n = 19. In males the Y chromosome is lost and in females one of the X chromosomes.

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Dental age in patients with Down syndrome

Brazilian Oral Research ◽

10.1590/s1806-83242007000300012 ◽

2007 ◽

Vol 21 (3) ◽

pp. 259-264 ◽

Cited By ~ 11

Author(s):

Mari Eli Leonelli de Moraes ◽

Michelle Silva Bastos ◽

Luis Roque de Araujo dos Santos ◽

Julio Cezar de Melo Castilho ◽

Luiz Cesar de Moraes ◽

...

Keyword(s):

Down Syndrome ◽

Statistical Analysis ◽

Permanent Teeth ◽

State University ◽

Dental Age ◽

Panoramic Radiographs ◽

Paulo State ◽

Males And Females ◽

School Of Dentistry ◽

Normal Standards

The aim of this research was to evaluate dental age in 102 patients with Down Syndrome, using panoramic radiographs. A software program developed by the Discipline of Radiology, School of Dentistry of São José dos Campos, São Paulo State University (UNESP), was used. A table of mineralization chronology of permanent teeth among Brazilians conceived by Nicodemo, Moraes and Medici Filho was used within the software. Statistical analysis of the results showed that 70.91% of the males and 61.21% of the females presented advanced dental age. Only 32.09% of the males and 38.79% of the females presented delayed dental age. Regarding the differences between the dental and chronological ages, two thirds of the males and females presented dental age with differences of up to 12 months, which means that they can be considered to be within normal standards, whereas only 18.87% of the males and 10.21% of the females presented dental age outside normal standards, with differences of over 24 months. In conclusion, the majority of the patients with Down Syndrome were considered to be within the normal standards of mineralization chronology.

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Retained primary teeth in STAT3 hyper-IgE syndrome: early intervention in childhood is essential

Orphanet Journal of Rare Diseases ◽

10.1186/s13023-020-01516-3 ◽

2020 ◽

Vol 15 (1) ◽

Author(s):

Iris Meixner ◽

Beate Hagl ◽

Carolin I. Kröner ◽

Benedikt D. Spielberger ◽

Ekaterini Paschos ◽

...

Keyword(s):

Primary Teeth ◽

Dental Treatment ◽

Elevated Serum ◽

Permanent Tooth ◽

Tooth Eruption ◽

Permanent Teeth ◽

Primary Tooth ◽

Hyper Ige Syndrome ◽

Tooth Roots ◽

Midline Defects

Abstract Background STAT3 hyper-IgE syndrome (STAT3-HIES) is a rare primary immunodeficiency that clinically overlaps with atopic dermatitis. In addition to eczema, elevated serum-IgE, and recurrent infections, STAT3-HIES patients suffer from characteristic facies, midline defects, and retained primary teeth. To optimize dental management we assessed the development of dentition and the long-term outcomes of dental treatment in 13 molecularly defined STAT3-HIES patients using questionnaires, radiographs, and dental investigations. Results Primary tooth eruption was unremarkable in all STAT3-HIES patients evaluated. Primary tooth exfoliation and permanent tooth eruption was delayed in 83% of patients due to unresorbed tooth roots. A complex orthodontic treatment was needed for one patient receiving delayed extraction of primary molars and canines. Permanent teeth erupted spontaneously in all patients receiving primary teeth extraction of retained primary teeth during average physiologic exfoliation time. Conclusions The association of STAT3-HIES with retained primary teeth is important knowledge for dentists and physicians as timely extraction of retained primary teeth prevents dental complications. To enable spontaneous eruption of permanent teeth in children with STAT3-HIES, we recommend extracting retained primary incisors when the patient is not older than 9 years of age and retained primary canines and molars when the patient is not older than 13 years of age, after having confirmed the presence of the permanent successor teeth by radiograph.

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What is the effect of preterm birth on permanent tooth crown dimensions? A systematic review and meta-analysis

PLoS ONE ◽

10.1371/journal.pone.0259293 ◽

2021 ◽

Vol 16 (11) ◽

pp. e0259293

Author(s):

Shaima Nasser Buhamer ◽

Eleftherios Kaklamanos ◽

Mawlood Kowash ◽

Iyad Hussein ◽

Anas Salami ◽

...

Keyword(s):

Preterm Birth ◽

Observational Studies ◽

Permanent Tooth ◽

Permanent Teeth ◽

Tooth Crown ◽

Extremely Preterm ◽

Newcastle Ottawa Scale ◽

Meta Regression ◽

Crown Dimensions ◽

Ottawa Scale

Background The permanent tooth formation process may be disrupted in preterm infants with potential discrepancies in size and subsequent occlusal disturbances. Objective To systematically analyse and quantitively synthesize the available evidence regarding the impact of preterm birth on permanent tooth crown dimensions. Search methods Unrestricted searches in 6 databases and manual searching of the reference lists in relevant studies were performed up to March 2021 (Medline via PubMed, CENTRAL, Cochrane Database of Systematic Reviews, Scopus, Web of Science, ProQuest Dissertations and Theses Global). Selection criteria Observational studies investigating permanent tooth crown dimensions in preterm and control full-term born individuals. Data collection and analysis Following study retrieval and selection, relevant data were extracted, and the Newcastle-Ottawa scale was used to assess the selection, comparability, and outcome domains. Exploratory synthesis and meta-regression were carried out using the random effects model. Results Three studies were located from the initially retrieved records and the assessments with the Newcastle-Ottawa scale identified issues regarding the selection and comparability domains. Overall, the mesiodistal and the buccolingual dimensions of the permanent teeth in both dental arches tended to be smaller in children born prematurely than full term children. Subgroup analyses showed statistically significant differences for the extremely preterm to control group comparisons for the incisors and the first molars. Meta-regression showed a modificatory effect of gestational age and racial background but not of birth weight and gender on tooth size. The quality of available evidence was rated at best as moderate. Conclusions Premature birth could potentially be associated with reduced tooth-crown dimensions in some permanent teeth especially in children born extremely preterm. Although the results from these observational studies should be approached with caution until more information becomes available, the possible clinical implications in terms of diagnosis and treatment planning should be considered. Registration PROSPERO (CRD42020182243).

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