-
Archives of Oral Biology Feb 2024This study intends to investigate the effect of a soft food diet on molar dentin formation during the occlusal establishment period. It can provide dietary guidance for...
OBJECTIVE
This study intends to investigate the effect of a soft food diet on molar dentin formation during the occlusal establishment period. It can provide dietary guidance for infants to strengthen their dental structure.
DESIGN
60 BALB/c mice were used to obtain mandibles during lactation (P0.5, P7.5, P15.5, P21.5) and occlusal establishment (P27.5, P33.5, P60.5). The mice were randomly divided into soft or hard diet groups after weaning at day 21.5. Hematoxylin-eosin and aniline blue staining were used to observe the morphology and number of odontoblasts and the amount of molar dentin formation. Immunohistochemistry was performed to observe the proliferation and apoptosis of odontoblasts. The in vivo fluorescence double-labeling was applied to evaluate the rate of molar dentin formation.
RESULTS
The soft diet group had poorer periodontal membrane development but more cervical dentin deposition. Alterations in morphology and the number of odontoblasts showed a stronger correlation with age rather than food hardness. There are no significant differences in proliferative and apoptotic behavior of dentin-forming cells between the two groups. Rather, it affected the rate of dentin deposition. The rate of dentin deposition was high in the soft diet group from P21.5 to P27.5, but it was surpassed by the hard diet group within P27.5-P33.5, and the difference between the two groups disappeared at P33.5-P60.5.
CONCLUSIONS
A soft diet promotes molar early cervical dentin formation. This advantage is caused by an enhanced odontoblast secretion rate rather than affecting the morphology, number, proliferation, or apoptosis of odontoblasts.
Topics: Humans; Female; Mice; Animals; Dentin; Dentinogenesis; Odontoblasts; Molar; Diet; Cell Differentiation
PubMed: 38056229
DOI: 10.1016/j.archoralbio.2023.105858 -
Anatomical Record (Hoboken, N.J. : 2007) Jun 2024We used fluorochrome labeling to study spatiotemporal variation of dentin apposition (DAR) and extension (DER) rates during crown and root formation of mandibular first...
We used fluorochrome labeling to study spatiotemporal variation of dentin apposition (DAR) and extension (DER) rates during crown and root formation of mandibular first molars from wild boar and domestic pigs. DAR was reconstructed along the course of dentinal tubules in four zones of the crown and in the upper root area. In all five zones, mean DAR increased during the first 30% to 40% of apposition, reaching highest values (22-23 μm/day) in the upper-lateral crown zone. Lowest values were recorded near the dentin-pulp interface (DPI). Typically, DARs in contemporaneously formed dentin areas were higher in more cuspally compared to more cervically/apically located zones. DER was high (>200 μm/day) in early postnatal crown dentin and then decreased markedly in cervical direction, with lowest values in the cervical crown zone. After this nadir, DER sharply increased in the upper 30% to 40% of the root extension, reaching values equaling (wild boar) or even surpassing (domestic pigs) those recorded in the upper lateral crown. After this peak, DER again decreased. While DAR did not differ markedly between wild boar and domestic pigs, the DER showed marked differences, both regarding maximum values (208.1 μm/day in wild boar, 272.2 μm/day in domestic pigs) and the timing of the root growth spurt, which occurred earlier in the domestic pigs. We consider the more rapid recruitment of secretory odontoblasts in domestic pigs (reflected by higher DER) a side effect of selection for rapid body growth during pig domestication.
Topics: Animals; Molar; Tooth Root; Dentin; Tooth Crown; Swine; Mandible; Odontogenesis; Dentinogenesis; Sus scrofa
PubMed: 38051150
DOI: 10.1002/ar.25358 -
Journal of Functional Biomaterials Nov 2023In recent years, alternative pulpal therapies targeting dentinogenesis signaling pathways using different peptides have been investigated. The aim of this study was to...
UNLABELLED
In recent years, alternative pulpal therapies targeting dentinogenesis signaling pathways using different peptides have been investigated. The aim of this study was to verify the effectiveness of poly(aspartic acid), pAsp, in dentin regeneration using an animal model.
METHODS
Mechanical pulp exposure was performed in the upper molars of 56 Wistar rats, randomly divided as follows (n = 14): control (no treatment); MTA group-pulp capping with mineral trioxide aggregate (MTA Angelus); pAsp group-application of 20 μL of pAsp solution (25 mg·mL); MTA+pAsp group-application of MTA mixed with pAsp (5:1 by mass). Animals were euthanized after 7 or 21 days. Histological sections were submitted to hematoxylin-eosin and Brown and Brenn staining and immunohistochemical analysis for osteopontin (OPN) and dentin matrix protein 1 (DMP 1).
RESULTS
At 7 days, an acute inflammatory infiltrate and the presence of disorganized mineralized tissue were observed in all groups. At 21 days, the quality and thickness of the reparative dentin in treated groups were superior to the control, and bacterial contamination was observed in two MTA-pAsp specimens. While all treated groups showed intense immunostaining for OPN at 21 days, only the pAsp group expressed DMP 1, indicating the presence of fully differentiated odontoblast-like cells.
CONCLUSION
Poly(aspartic) acid promoted dentin regeneration in rat molars in the absence of an additional calcium source and may be an alternative to MTA as a pulp-capping agent.
PubMed: 37998106
DOI: 10.3390/jfb14110537 -
Australian Endodontic Journal : the... Apr 2024This study aimed to assess the calcium (Ca) and hydroxyl (OH) ion-releasing ability, namely the biointeractivity of eggshell-derived hydroxyapatite (ESDHA) in comparison...
This study aimed to assess the calcium (Ca) and hydroxyl (OH) ion-releasing ability, namely the biointeractivity of eggshell-derived hydroxyapatite (ESDHA) in comparison with mineral trioxide aggregate (MTA) and calcium hydroxide (CH). ESDHA, MTA and CH samples (n = 10; 8 × 1.6 mm) were immersed in 10 mL of deionised water (37°C, pH 6.8). Ca and OH ion releases were detected in 1, 7 and 21 days. Scanning electron microscopy and Fourier transform infrared spectroscopy analyses were also conducted. IBM SPSS 20.0 was used for statistical analyses. The cumulative Ca ions (56.22 ± 11.28 ppm) were detected as most significant in ESDHA (day 21; p < 0.05). The OH ion values of the ESDHA group were statistically higher than MTA and CH (days 1 and 7; p < 0.05). ESDHA and CH showed a similar pattern with sharp peaks in Ca, oxygen and carbon elements. ESDHA being a sustainable material with a high ion-releasing ability may be a preferable alternative to the commercial vital pulp therapy agents.
Topics: Animals; Calcium Compounds; Dental Pulp Capping; Egg Shell; Silicates; Calcium Hydroxide; Durapatite; Oxides; Drug Combinations; Aluminum Compounds
PubMed: 37964493
DOI: 10.1111/aej.12809 -
Pediatric and Developmental Pathology :... 2023Unique dental conditions in children include odontogenic cysts and tumors, hereditary dental diseases, developmental anomalies, and lesions associated with the eruption... (Review)
Review
Unique dental conditions in children include odontogenic cysts and tumors, hereditary dental diseases, developmental anomalies, and lesions associated with the eruption of the primary or permanent teeth. Many of these conditions have long lasting effects on the adult dentition in terms of affecting esthetics, function, and overall quality of life. Inherited dental syndromes affect the dental hard tissues specifically the enamel, dentin, and/or cementum in a generalized manner, involving both primary and permanent teeth. These conditions manifest in altered quality or quantity of the hard tissues, leading to fragility, tooth loss and dental diseases such as caries, periapical pathology, and periodontal disease. This category includes amelogenesis imperfecta, dentinogenesis imperfecta, dentin dysplasia, hypophosphatasia, and hypophosphatemia. Developmental defects such as regional odontodysplasia are defined by involvement of the primary and permanent dentition in a localized manner, identified in early childhood. This review will elaborate on the histologic findings in these selected dental conditions with a discussion on clinical and radiographic findings, as well as molecular features wherever appropriate.
Topics: Adult; Humans; Child, Preschool; Child; Quality of Life; Tooth; Amelogenesis Imperfecta; Syndrome
PubMed: 37962547
DOI: 10.1177/10935266231207045 -
Frontiers in Cell and Developmental... 2023Heparan sulfate proteoglycans (HSPGs) surround the surface of odontoblasts, and their modification affects their affinity for Wnt ligands. This study proposes applying...
On-demand chlorine dioxide solution enhances odontoblast differentiation through desulfation of cell surface heparan sulfate proteoglycan and subsequent activation of canonical Wnt signaling.
Heparan sulfate proteoglycans (HSPGs) surround the surface of odontoblasts, and their modification affects their affinity for Wnt ligands. This study proposes applying Matching Transformation System (MA-T), a novel chlorinated oxidant, to enhance dentinogenesis. MA-T treatment in odontoblasts decreased sulfation of HSPG and upregulated the expression of () and () via activation of canonical Wnt signaling . application of MA-T also enhanced dentin matrix formation in developing tooth explants. Reanalysis of a public single-cell RNA-seq dataset revealed significant Wnt activity in the odontoblast population, with enrichment for and . Silencing assays showed that and were redundant in inducing and mRNA expression. These Wnt ligands' expression was upregulated by MA-T treatment, and TCF/LEF binding sites are present in their promoters. Furthermore, the Wnt inhibitors Notum and Dkk1 were enriched in odontoblasts, and their expression was also upregulated by MA-T treatment, together suggesting autonomous maintenance of Wnt signaling in odontoblasts. This study provides evidence that MA-T activates dentinogenesis by modifying HSPG and through subsequent activation of Wnt signaling.
PubMed: 37954207
DOI: 10.3389/fcell.2023.1271455 -
L' Orthodontie Francaise Nov 2023The precise diagnosis of dental structural anomalies is an essential step preceding our restorative and orthodontic therapies. Indeed, first of all, it is necessary to...
INTRODUCTION
The precise diagnosis of dental structural anomalies is an essential step preceding our restorative and orthodontic therapies. Indeed, first of all, it is necessary to identify the type of structural anomaly and to determine if it is an isolated or a syndromic form: the dental anomaly could be included in a more complex clinical picture combining other clinical signs. Moreover, the establishment of the diagnosis will allow the practitioner to adapt his clinical protocol according to the observed dental structure anomaly. The choice of the bonding material, the type of preparation (no prep, prep less, complete eviction), and the application of a deproteinization protocol with sodium hypochlorite depend to the structural defect.
MATERIAL AND METHOD
The diagnosis of dental structural anomalies is based on several key points described in this article in order to facilitate the practitioner's diagnostic approach.
CONCLUSION
The diagnosis of amelogenesis or dentinogenesis imperfecta should justify the search for other signs to determine whether the anomaly of tooth structure is isolated or syndromic.
Topics: Humans; Amelogenesis; Dental Materials; Sodium Hypochlorite
PubMed: 37930342
DOI: 10.1684/orthodfr.2023.134 -
Bone Feb 2024The SP7 gene encodes a zinc finger transcription factor (Osterix), which is a member of the Sp subfamily of sequence-specific DNA-binding proteins, playing an important...
The SP7 gene encodes a zinc finger transcription factor (Osterix), which is a member of the Sp subfamily of sequence-specific DNA-binding proteins, playing an important role in osteoblast differentiation and maturation. SP7 pathogenic variants have been described in association with different allelic disorders. Monoallelic or biallelic SP7 variants cause Osteogenesis imperfecta type XII (OI12), a very rare condition characterized by recurrent fractures, skeletal deformities, undertubulation of long bones, hearing loss, no dentinogenesis imperfecta, and white sclerae. Monoallelic or biallelic SP7 variants may also cause sclerotic skeletal dysplasias (SSD), partially overlapping with Juvenile Paget's disease and craniodiaphyseal dysplasia, characterized by skull hyperostosis, long bones sclerosis, large ribs and clavicles, and possible recurrent fractures. Here, we report the long-term follow-up of an 85-year-old woman presenting with a complex bone disorder including features of either OI12 (bone fragility with multiple fractures, severe deformities and short stature) or SSD (striking skull hyperostosis with optic atrophy, very large ribs and clavicles and long bones sclerosis). Exome sequencing showed previously undescribed biallelic loss of function variants in the SP7 gene: NM_001173467.2(SP7): c.359_362del, p.(Asp120Valfs*11); NM_001173467.2(SP7): c.1163_1174delinsT, p.(Pro388Leufs*33). RT-qPCR confirmed a severely reduced SP7 transcription compared to controls. Our report provides new insights into the clinical and molecular features and long-term outcome of SP7-related bone disorders (SP7-BD), suggesting a continuum phenotypic spectrum characterized by bone fragility, undertubulation of long bones, scoliosis, and very heterogeneous bone mineral density ranging from osteoporosis to osteosclerosis.
Topics: Female; Humans; Aged, 80 and over; Follow-Up Studies; Sclerosis; Osteogenesis Imperfecta; Bone and Bones; Hyperostosis
PubMed: 37918503
DOI: 10.1016/j.bone.2023.116953 -
International Endodontic Journal Jan 2024Dental pulp is richly innervated by nerve fibres, which are mainly involved in the sensation of pain. Aside from pain sensation, little is known regarding the role of...
AIM
Dental pulp is richly innervated by nerve fibres, which are mainly involved in the sensation of pain. Aside from pain sensation, little is known regarding the role of dental innervation in reparative dentine formation. We herein generated a mouse model of experimental dentine injury to examine nerve sprouting within the odontoblast and subodontoblastic layers and investigated the potential effects of this innervation in reparative dentinogenesis.
METHODOLOGY
Mouse tooth cavity model (bur preparation + etching) was established, and then nerve sprouting, angiogenesis and reparative dentinogenesis were determined by histological and immunofluorescent staining at 1, 3, 7, 14 and 28 days postoperatively. We also established the mouse-denervated molar models to determine the role of sensory and sympathetic nerves in reparative dentinogenesis, respectively. Finally, we applied calcitonin gene-related peptide (CGRP) receptor antagonist to analyse the changes in angiogenesis and reparative dentinogenesis.
RESULTS
Sequential histological results from dentine-exposed teeth revealed a significant increase in innervation directly beneath the injured area on the first day after dentine exposure, followed by vascularisation and reparative dentine production at 3 and 7 days, respectively. Intriguingly, abundant type H vessels (CD31 Endomucin ) were present in the innervated area, and their formation precedes the onset of reparative dentine formation. Additionally, we found that sensory denervation led to blunted angiogenesis and impaired dentinogenesis, while sympathetic denervation did not affect dentinogenesis. Moreover, a marked increase in the density of CGRP nerve fibres was seen on day 3, which was reduced but remained elevated over the baseline level on day 14, whereas the density of substance P-positive nerve fibres did not change significantly. CGRP receptor antagonist-treated mice showed similar results as those with sensory denervation, including impairments in type H angiogenesis, which confirms the importance of CGRP in the formation of type H vessels.
CONCLUSIONS
Dental pulp sensory nerves act as an essential upstream mediator to promote angiogenesis, including the formation of type H vessels, and reparative dentinogenesis. CGRP signalling governs the nerve-vessel-reparative dentine network, which is mostly produced by newly dense sensory nerve fibres within the dental pulp.
Topics: Mice; Animals; Calcitonin Gene-Related Peptide; Dental Pulp; Angiogenesis; Dentin, Secondary; Pain
PubMed: 37874659
DOI: 10.1111/iej.13989 -
Journal of Veterinary Dentistry Oct 2023Dentinogenesis imperfecta is a rare, autosomal dominant, hereditary disorder that occurs in humans and animals. In humans, known causative genetic mutations have been... (Review)
Review
Dentinogenesis imperfecta is a rare, autosomal dominant, hereditary disorder that occurs in humans and animals. In humans, known causative genetic mutations have been elucidated; however, veterinary literature on the topic is limited. This case report describes a 1-year-old female Labrador Retriever who presented for evaluation of generalized discoloration of the permanent dentition with historical discoloration of the deciduous dentition. Radiographic and histopathological findings will be discussed, as well as an in-depth review of the current human and veterinary literature pertaining to the pathogenesis and treatment options for dentinogenesis imperfecta.
PubMed: 37872656
DOI: 10.1177/08987564231208359