Early Tooth Eruption Research Articles

Chronological Age versus Corrected Age of First Tooth Eruption in Jordanian Premature Infants

Objective: To evaluate the chronological and corrected age and the impact of neonatal factors on first tooth eruption of Jordanian premature infants. Methods: A prospective study of 110 Jordanian preterm infants (gestational age 1500 grams) than ( 32 weeks) than (< 32 weeks). There were great significant differences in birth weight and gestational age between normal and delayed groups when the chronological age rather than corrected age used (P< 0.05, Fisher's exact test). Introduction of total parenteral nutrition, breast milk, and full term formula to premature infants associated with early first tooth eruption (P< 0.05, Fisher's exact test). Conclusion: Introduction of total parenteral nutrition, breast milk, and preterm formula to premature infants associated with early first tooth eruption. The significant difference between groups was mainly with chronological age rather than corrected age.

Papillon-Lefèvre syndrome: clinical presentation and management options.

Papillon–Lefèvre syndrome (PLS) is a rare autosomal recessive disorder, characterized by diffuse palmoplantar keratoderma and precocious aggressive periodontitis, leading to premature loss of deciduous and permanent dentition at a very young age. Various etiopathogenic factors are associated with the syndrome, like immunologic alterations, genetic mutations, and the role of bacteria. Dentists play a significant role in the diagnosis and management of PLS as there are characteristic manifestations like periodontal destruction at an early age and an early eruption of permanent teeth. Here, we are presenting an elaborate review of PLS, its etiopathogenesis, clinical presentation, and management options.

PP12.11 – 2550: Atypical forms of 4H leukodystrophy

Objective 4H leukodystrophy (4H) is a rare inherited disorder characterized by hypomyelination, hypodontia and hypogonadotropic hypogonadism, although dental and puberty development may be normal. The disease starts with early-onset ataxia and neurologic deterioration from the second decade. Recessive mutations in either POLR3A or POLR3B, encoding the two largest subunits of the RNA polymerase III complex, cause the disease. Recently, we identified mutation-positive patients without hypomyelination. Aim of this study was to provide further characterization of this subgroup. Methods We performed a multi-institutional cross-sectional observational study of the clinical, radiological and genotypic characteristics of patients carrying POLR3A or POLR3B mutations, but without hypomyelination on brain MRI in our database. Results Six patients from five families with mutations in either POLR3A or POLR3B were identified. We could distinguish two different presentations: three unrelated patients with progressive T2-hyperintense signal abnormalities in the internal capsule and otherwise normal MRI (group 1, mutations in POLR3A) and three patients with cerebellar atrophy and no or only mild signal changes of their supratentorial white matter (group 2, mutations in POLR3A in one family and in POLR3B in a single patient). The patients of group 1 had hypodontia, which led to the suspicion of a 4H-related disorder. The patients of group 2 had no hypodontia, but one of them had early tooth eruption at three weeks of age, prompting targeted genetic analysis. The two remaining patients were identified by whole-exome sequencing. Mutations found in all patients were compound heterozygous and included at least one mutation leading to altered splicing. Conclusion Hypomyelination is not an obligatory feature of mutations in POLR3A or POLR3B. Hypodontia may be helpful in identifying candidates, but is not obligatory, as already known from patients with classical 4H leukodystrophy. Mutations involving aberrant gene splicing seem to play an important role in these atypical presentations.

Evolution of Klk4 and enamel maturation in eutherians.

Kallikrein-related peptidase 4 (KLK4) is a secreted serine protease that degrades residual enamel proteins to facilitate their removal by ameloblasts, which increases mineralization and hardens the enamel. Mutations in human KLK4 cause hypomaturation amelogenesis imperfecta. Enamel formed by Klk4 null mice is normal in thickness and prism structure, but the enamel layer retains proteins, is hypomineralized, and undergoes rapid attrition following tooth eruption. We searched multiple databases, retrieved Klk4 and Klk5 from various mammalian genomes, and identified Klk4 in 46 boreoeutherian genomes. In non-Boreoeutheria, Klk4 was detected in only one afrotherian genome (as a pseudogene), and not in the other six afrotherian, two xenarthran, or three marsupial genomes. In contrast, Klk5 was detected in both marsupial and eutherian mammals. Our phylogenetic and mutation rate analyses support the hypothesis that Klk4 arose from Klk5 by gene duplication near the divergence of Afrotheria, Xenarthra and Boreoeutheria, and that functionally-differentiated Klk4 survived only in Boreoeutheria. Afrotherian mammals share the feature of delayed dental eruption relative to boreoeutherian mammals. KLK4 shortens the time required for enamel maturation and could have alleviated negative selection following mutations that resulted in thicker enamel or earlier tooth eruption, without reducing enamel hardness or causing dental attrition.

The role of polymorphisms associated with early tooth eruption in dental and occlusal traits in East Asian populations

ObjectiveA recent study suggested that rs6504340, a polymorphism within the homeobox B (HOXB) gene cluster, is associated with the susceptibility for malocclusions in Europeans. The resulting malocclusions require orthodontic treatment. The aim of this study was to investigate the association of rs6504340 and other dentition-implicated polymorphisms with dental and occlusal traits in Korean and Japanese populations.MethodsThe study participants included 223 unrelated Koreans from the Busan area and 256 unrelated Japanese individuals from the Tokyo metropolitan area. DNA samples were extracted from saliva specimens. Genotyping for rs6504340 and four single nucleotide polymorphisms (SNPs) that have been shown to be associated with the timing of first tooth eruption and the number of teeth at 1 year of age (rs10506525, rs1956529, rs9674544, and rs8079702) was performed using TaqMan assays. The Index of Orthodontic Treatment Need (IOTN), overjet, overbite, arch length discrepancy, crown sizes, and length and width of the dental arches were measured. Spearman's correlation coefficients were calculated to evaluate relationships between rs6504340 and these dental/occlusal traits.ResultsWe evaluated the aesthetic components and dental health components of the IOTN in the Korean and Japanese populations and found that neither rs6504340 nor the other four SNPs showed any association with dental and occlusal traits in these East Asian populations.ConclusionsThese negative results suggest that further research is needed to identify the genetic determinants of malocclusions in order to reach a consensus.

Early eruption of permanent canines

Systemic and local factors can modify the eruption time of teeth. Generalized eruption time changes could be due to some systemic diseases like hyperthyroidism, hypophosphatasia, precocious puberty, Proteus syndrome, etc. Localized early eruption of permanent teeth could be due to early extraction of deciduous teeth. Presented here is an extremely rare case of early eruption of permanent canines in a 7-year old female child. Though the number of such cases is very limited, the clinician should poses adequate knowledge and keeps an open eye to identify such cases.

Pattern and pace of dental eruption in Tarsius

This article uses data on the dental eruption pattern and life history of Tarsius to test the utility of Schultz's rule. Schultz's rule claims a relationship between the relative pattern of eruption and the absolute pace of dental development and life history and may be useful in reconstructing life histories in extinct primates. Here, we document an unusual eruption pattern in Tarsius combining early eruption (relative to molars) of anterior replacement teeth (P2 and incisors) and relatively late eruption of the posterior replacement teeth (C, P3, and P4). This eruption pattern does not accurately predict the "slow" pace of life documented for Tarsius [Roberts: Int J Primatol 15 (1994) 1-28], nor aspects of life history directly associated with dental development as would be expected using Schultz's rule. In Tarsius, the anterior teeth and M1 erupt at an early age and therefore are not only fast in a relative sense but also fast in an absolute sense. This seems to be related to a developmental anomaly in the deciduous precursor teeth, which are essentially skipped. This decoupling among dental eruption pattern, dental eruption pace, and life history pace in Tarsius undermines the assumptions that life histories can accurately be described as "fast" or "slow" and that dental eruption pattern alone can be used to infer overall life history pace. The relatively and absolutely early eruption of the anterior dentition may be due to the utility of these front teeth in early food acquisition rather than with the pace of life history.

Eruption times and patterns of permanent teeth in school children of India

To study the eruption pattern of permanent teeth excluding third molars in school children of Mysore, South India. To compare the eruption times determined with previous studies. To determine range of variation of the eruption time of each tooth and evaluate if any preponderance exists in the eruption timings of maxillary and mandibular teeth and between boys and girls. This was a descriptive cross sectional study. A random sample of 5007 school children in the age group of 5-14 years was selected. The mean age of eruption of individual permanent teeth was recorded and results were analyzed using Probit analysis. The study population included 2371 boys constituting 47.26% and 2636 girls constituting 52.65% of the total sample. In the age group of 5 years, one of the permanent teeth was found to be erupted. In the age group of 14 years, all the permanent teeth except third molar had erupted. Girls showed early tooth eruption compared to boys. Mandibular teeth erupted earlier than maxillary teeth in both the sexes. Right and left sided teeth erupted at the same time in both the arches. The mean ages of eruption obtained from the present study are strikingly comparable with those of other investigators in different populations across the world. Since the current study involves a large sample of children, the data reported in this study could be used as standards when assessing permanent tooth eruption in Indian children.

Bone resorption control of tooth eruption and root morphogenesis: Involvement of the receptor activator of NF‐κB (RANK)

Activation of the receptor activator of NF-κB (RANK) is a crucial step in osteoclastogenesis. Loss- and gain-of-function mutations in the Rank gene cause, respectively, osteopetrosis and several forms of extensive osteolysis. Tooth and alveolar bone alterations are associated with these pathologies but remain to be better characterized. The aim of the present study was to establish the tooth and alveolar bone phenotype of a transgenic mouse model of RANK over-expression in osteoclast precursors. Early tooth eruption and accelerated tooth root elongation were observed subsequent to an increase in osteoclast numbers surrounding the tooth. The final root length appeared not to be affected by RANK over-expression, but a significant reduction in root diameter occurred in both control and root-morphogenesis-defective Msx2 null mutant mice. These results indicate that root length is independent of the surrounding bone resorption activity. In contrast, root diameter is sensitive to the activity of alveolar bone osteoclasts. These data suggest that early eruption and thin root are phenotypic features that could be associated with extensive osteolytic pathologies.

Klippel-Trénaunay Syndrome Manifesting as Gingival Overgrowth and Teeth Agenesis

Klippel-Trénaunay syndrome (KTS) is characterized by triad of venous varicosity, naevus flammeus, and soft/hard tissue hypertrophy. Manifestations of the syndrome in the head and neck region are rare, but in some cases hemangioma of the lips, tongue, and gums, open bite and cross bite, and early tooth eruption are associated with the disease. We report a 12-year-old KTS patient with gingival hyperplasia, congenital missing teeth, and increased mucosal vascularization as oral manifestations. All manifestations of the KTS were observed on the same side of the head, except bilateral missing teeth. Histological examination showed several vascular enlargements in enlarged gingiva. It is suggested that oral manifestations of the syndrome are generally related to the severity of the disease, but they do not always present in the same pattern.

Congenital infiltrating lipomatosis of the face: Report of three cases and review of the literature

Three new cases of hemifacial hypertrophy caused by congenital infiltrating lipomatosis of the face are reported. The literature on infiltrating lipomatosis of the face is reviewed with an emphasis on accompanying anomalies and treatment strategies. In this study, the clinical features, radiographic findings, histopathology, and postoperative results were analyzed in three patients with facial infiltrating lipomatosis. The condition was diagnosed in infancy (one male subject, two female subjects) and characterized by enlargement of the cheek. Most patients had early eruption of ipsilateral deciduous and permanent teeth. Computed tomography and magnetic resonance imaging showed an infiltrated soft-tissue mass of fatty density and skeletal overgrowth. Multiple resections were performed on two patients. Described first by Slavin and colleagues in 1989, Facial infiltrating lipomatosis is a rare congenital disorder in which mature lipocytes invade adjacent tissue. The phenotypic features include soft-tissue and skeletal hypertrophy, premature dental eruption, and regional macrodontia. Due to its diffuse infiltration and involvement of important facial structures, complete surgical excision is often impossible. The aetiology, natural history, optimal management, and relationship to other disorders of fatty overgrowth are unclear. Because surgical removal of the mass is usually unsuccessful, specific management of this condition will require insight into its pathogenesis.

National Pathfinder Survey on Children’s Oral Health in Italy: Pattern and Severity of Caries Disease in 4-Year-Olds

This paper describes the dental health status of Italian 4-year-olds in 2004/2005 and analyzes the association between caries in preschool children and some background characteristics in children and parents. Caries was recorded according to WHO criteria. 5,538 subjects were examined. Information on the children’s and their parents’ social, behavioral, ethnic and demographic status was obtained through a series of closed questions. Bivariate analysis was performed to investigate the association between caries and background characteristics. The probability of being an extra zero for the dmfs index was estimated via the zero-inflated negative binomial regression model (ZINB). 78.4% (95% CI = 77.2–79.6) of the children were caries-free. The national mean dmfs index was 1.36 (95% CI = 1.15–1.57), ranging from 1.22 (95% CI = 1.03–1.42) in the Italian North-East to 1.73 (95% CI = 0.83–2.63) in the South section. Significant bivariate associations between caries experience and risk factors were observed for parents’ nationality (not Italian vs. Italian: p < 0.001), parents’ educational levels (low vs. high: p < 0.001), preterm birth (yes vs. no: p = 0.011), prolonged breastfeeding (≤13 months vs. >13 months: p = 0.038) and early tooth eruption (<6 months as reference: p = 0.004). Multivariable analysis (ZINB) showed that children with a low caries risk level had a higher probability of being an extra zero; in particular, children from fathers with a high educational level showed a probability of being an extra zero of 0.22. The results suggest a need to plan preventive programs to reduce oral health disparities among Italian preschool children, based on educational intervention with parents and children concerning oral health and caries prevention.

Natal and neonatal teeth: a review

The presence of teeth in newborn is uncommon. Sometimes it occurs, appearing in about one in every 2,000 to 3,000 live births. Natal teeth are teeth already present at time of birth, neonatal teeth erupt during the first 30 days after birth. The normal eruption of the first teeth is quite exciting but their occurrence at birth or few days after birth is quite disturbing because of societal unpleasant reaction towards it in some communities and calls for concern. The majority of natal and neonatal teeth represent the early eruption of normal primary teeth. Less than 10% of natal teeth are supernumerary. Although the majority of natal teeth are isolated incidents, their presence may be associated with some syndromes. Complications include discomfort during suckling causing irritation and trauma to infants tongue, sublingual ulceration, laceration of the mother's breasts and aspiration of the teeth. The objective of the present study was to present a review of the literature on the current information on this topic and give treatment options if necessary.

Early primary tooth eruption in neurofibromatosis 1 individuals

Early primary tooth eruption in neurofibromatosis 1 individuals

The eruption of permanent incisors and first molars in prematurely born children.

The purpose of this work was to examine whether the clinical eruption of the permanent first molars and incisors is affected by pre-term birth. The data applied to 328 prematurely born white and black children and 1804 control children who participated in the Collaborative Perinatal Project (USA) in the early 1960s and 1970s. The dental examinations had been performed in a cross-sectional manner at ages varying from 6 to 12 years in 95 per cent of cases (range 5-14 years). Dental casts were placed in matched pairs by sex, race and conceptional age for comparison of the four clinical stages of eruption of the permanent incisors and first molars between the pre-term and control children. The results showed significantly (P < 0.05) earlier tooth eruption in the pre-term children. The findings suggest that the eruption process is earlier in those teeth that go through a sensitive period circumnatally, being at the pre-eruptive stages and entering the first phases of mineralization under the influence of various neonatal systemic factors and accelerated growth period (catch-up growth) with related unknown mechanisms, which may influence the eruption of the permanent incisors and first molars in prematurely born children.

Facial infiltrating lipomatosis.

Facial infiltrating lipomatosis is a rare congenital disorder in which mature lipocytes invade adjacent tissue. The phenotypic features include soft-tissue and skeletal hypertrophy, premature dental eruption, and regional macrodontia. There is a high risk for regrowth after resection that is, perforce, subtotal. The etiology, natural history, optimal management, and relationship to other disorders of fatty overgrowth are unclear. In this study, the clinical features, radiographic findings, histopathology, and postoperative results were analyzed in 13 patients with facial infiltrating lipomatosis. The condition was diagnosed in infancy (eight male subjects, five female subjects) and characterized by enlargement of the cheek (n = 12) or chin (n = 1). Other findings included cutaneous capillary blush (n = 9), ipsilateral macroglossia (n = 8), and mucosal neuromas (n = 6). Most patients had early eruption of ipsilateral deciduous and permanent teeth (n = 12). Computed tomography and magnetic resonance imaging showed an infiltrated soft-tissue mass of fatty density (n = 13) and skeletal overgrowth (n = 9). Multiple resection was performed on six patients (mean number of operations per patient, 2.5; range, one to six operations); regrowth and/or worsening of the capillary stain occurred in all six patients. Because surgical removal of the mass is usually unsuccessful, specific management of this condition will require insight into its etiopathogenesis. Given the presence of mucosal neuromas and lipomatosis, this study included testing for the known mutations in three entities that are associated with these soft-tissue findings (Cowden syndrome, Bannayan-Riley-Ruvalcava syndrome, and multiple endocrine neoplasia type 2B). Results of DNA analyses for these germline mutations were negative. It is more likely that this disorder is caused by a somatic mutation involving a local increase in growth factor(s).

Histological study on the chronology of the developing dentition in gorilla and orangutan

AbstractThe single previous study on tooth development in great apes (Dean and Wood: Folia Primatol. (Basel) 36:111–127, 1981) is of limited value because it is based on cross‐sectional radiographic data. This study considers problems in defining stages of tooth development in radiographs of developing ape dentitions and provides data on tooth chronology in Pongo pygmaeus and Gorilla gorilla by using histological methods of analysis. Crown formation times were estimated in individual teeth, and an overall chronology of dental development was found by registering teeth forming at the same time by using incremental growth lines. The earlier radiographic study correctly identified the molar and second premolar chronology and sequence in great apes, but significantly underestimated crown formation times in incisors, first premolars, and canine teeth in particular. Ape anterior tooth crowns take longer to form than the equivalent human teeth, but the overall dental developmental period in great apes is substantially shorter than in humans. Gorilla root extension rates appear to be fast, up to approximately 13 μm/day. This rapid root growth, associated with early tooth eruption, appears to be the developmental basis for the observed differences in timing between developing dentitions in great apes and humans.

Regulation of gene expression by epidermal growth factor.

Many constituents of serum and of the extracellular environment are essential for stimulation of cell growth and maintenance of differentiated function. Peptide growth factors form one subset of such components and epidermal growth factor (EGF) is one of the best-defined members of this class of growth regulatory substances. Many advances have been made in understanding mechanisms which underlie biological activities of EGF since it was first described by Stanley Cohen as a peptide present in nerve growth factor preparations that promoted early eyelid opening and tooth eruption in mice (1). Because physiological and cellular responses to EGF have been widely reviewed (2–6), this article emphasizes the role of EGF in regulating gene expression.KeywordsEpidermal Growth Factor ReceptorMutant Epidermal Growth Factor ReceptorEpidermal Growth Factor Receptor GeneSerum Response FactorGTPase Activate ProteinThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

授乳法の変更により治癒したＲｉｇａ‐Ｆｅｄｅ病の１例

A new therapy for Riga-Fede's disease is reported. It is well-known that the ulceration at the sublingual surface in infants is caused by mechanical stimulation of neonatal teeth or early eruption of anterior deciduous teeth. In many clinics tooth extraction or smo-othing incisal edge was usually performed to remove the stimulation. However, primary denti-tion and occulusion would be influenced by extraction of an anterior deciduous tooth.In the present case, a soft and long artificial nipple, which is generally used after cleft lip operation, was employed to modify tongue movements during feeding. This method made the tongue movement smaller, and mechanical stimulation to tongue was reduced. After two weeks the ulcer completely disappeared. This therapy seems to be of very simple, effective and conservative approach for treating Riga-Fede's disease.

2,3,7,8-Tetrachlorodibenzo-p-dioxin causes an increase in protein kinases associated with epidermal growth factor receptor in the hepatic plasma membrane.

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD), administered to male rats at a single intraperitoneal (IP) injection dose of 25 micrograms/kg causes down-regulation of epidermal growth factor (EGF) receptor in the plasma membrane of rat liver which starts after two days and continues throughout the experimental period (20 days). Using monoclonal antibody to EGF receptor, it was determined that TCDD-caused EFG receptor down-regulation in the rat liver was accompanied by increased protein kinase activity. Such an increase in the protein kinase activity involves, at least in part, an activation of protein tyrosine kinase. Examination of serum samples from control and treated rats revealed no detectable difference in the level of EGF itself or EGF receptor-reacting substances (eg, hormones and other growth factors). In vivo TCDD caused early eye opening and tooth eruption and poor body weight gain and hair growth in mouse neonates similar to those observed with exogenously administered EGF. The results indicate that such EGF receptor-mediated effect of TCDD has some toxocilogical significance in vivo. Although TCDD causes significant reduction in [125I]-EGF binding in the hepatic plasma membrane in susceptible strains of mice, it has only modest effects in tolerant strains. The results are consistent with the idea that the action of TCDD on the EGF receptor is mediated through the cytosolic/nuclear TCDD receptor, which is known to be regulated by the Ah locus.