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Chun YHP, Tan C, Villanueva O, Colley ME, Quintanilla TJ, Basiouny MS, Hartel CA, Critchfield CS, Bach SBH, Fajardo RJ, Pham CD. Overexpression of ameloblastin in secretory ameloblasts results in demarcated, hypomineralized opacities in enamel. Front Physiol 2024; 14:1233391. [PMID: 38274050 PMCID: PMC10808694 DOI: 10.3389/fphys.2023.1233391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Accepted: 11/01/2023] [Indexed: 01/27/2024] Open
Abstract
Introduction: Developmental defects of the enamel manifest before tooth eruption and include amelogenesis imperfecta, a rare disease of underlying gene mutations, and molar-incisor hypomineralization (MIH), a prevalent disease in children originating from environmental and epigenetic factors. MIH enamel presents as the abnormal enamel marked by loss of translucency, demarcation between the healthy and affected enamel, and reduced mineral content. The pathophysiology of opaque, demarcated enamel lesions is not understood; however, the retention of enamel proteins in the matrix has been suggested. Ameloblastin (Ambn) is an enamel protein of the secreted calcium-binding phosphoproteins (SCPPs) critical for enamel formation. When the Ambn gene is mutated or deleted, teeth are affected by hypoplastic amelogenesis imperfecta. Methods: In this study, enamel formation in mice was analyzed when transgenic Ambn was overexpressed from the amelogenin promoter encoding full-length Ambn. Ambn was under- and overexpressed at six increasing concentrations in separate mouse lines. Results: Mice overexpressing Ambn displayed opaque enamel at low concentrations and demarcated lesions at high concentrations. The severity of enamel lesions increased starting from the inner enamel close to the dentino-enamel junction (DEJ) to span the entire width of the enamel layer in demarcated areas. Associated with the opaque enamel were 17-kDa Ambn cleavage products, a prolonged secretory stage, and a thin basement membrane in the maturation stage. Ambn accumulations found in the innermost enamel close to the DEJ and the mineralization front correlated with reduced mineral content. Demarcated enamel lesions were associated with Ambn species of 17 kDa and higher, prolonged secretory and transition stages, a thin basement membrane, and shortened maturation stages. Hypomineralized opacities were delineated against the surrounding mineralized enamel and adjacent to ameloblasts detached from the enamel surface. Inefficient Ambn cleavage, loss of contact between ameloblasts, and the altered basement membrane curtailed the endocytic activity; thus, enamel proteins remained unresorbed in the matrix. Ameloblasts have the ability to distinguish between Ambn concentration and Ambn cleavage products through finely tuned feedback mechanisms. The under- or overexpression of Ambn in murine secretory ameloblasts results in either hypoplastic amelogenesis imperfecta or hypomineralization with opaque or sharply demarcated boundaries of lesions, similar to MIH.
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Affiliation(s)
- Yong-Hee Patricia Chun
- Department of Periodontics, School of Dentistry, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States
- Department of Cell Systems and Anatomy, School of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States
- Department of Molecular Medicine, School of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States
| | - Chunyan Tan
- Department of Periodontics, School of Dentistry, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States
| | - Omar Villanueva
- Department of Periodontics, School of Dentistry, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States
| | - Madeline E. Colley
- Department of Chemistry, University of Texas San Antonio, San Antonio, TX, United States
- Department of Biochemistry, Vanderbilt University, Nashville, TN, United States
- Mass Spectrometry Research Center, Vanderbilt University, Nashville, TN, United States
| | - Travis J. Quintanilla
- Department of Periodontics, School of Dentistry, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States
| | - Mohamed S. Basiouny
- Department of Periodontics, School of Dentistry, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States
| | - Caldonia A. Hartel
- Department of Periodontics, School of Dentistry, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States
| | - Cameron S. Critchfield
- Department of Periodontics, School of Dentistry, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States
| | - Stephan B. H. Bach
- Department of Chemistry, University of Texas San Antonio, San Antonio, TX, United States
| | - Roberto J. Fajardo
- Department of Clinical and Applied Science Education, School of Osteopathic Medicine, University of the Incarnate Word, San Antonio, TX, United States
| | - Cong-Dat Pham
- Department of Periodontics, School of Dentistry, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States
- Department of Cancer Systems Imaging, University of Texas MD Anderson Cancer Center, Houston, TX, United States
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Atia GA, Shalaby HK, Roomi AB, Ghobashy MM, Attia HA, Mohamed SZ, Abdeen A, Abdo M, Fericean L, Bănățean Dunea I, Atwa AM, Hasan T, Mady W, Abdelkader A, Ali SA, Habotta OA, Azouz RA, Malhat F, Shukry M, Foda T, Dinu S. Macro, Micro, and Nano-Inspired Bioactive Polymeric Biomaterials in Therapeutic, and Regenerative Orofacial Applications. Drug Des Devel Ther 2023; 17:2985-3021. [PMID: 37789970 PMCID: PMC10543943 DOI: 10.2147/dddt.s419361] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Accepted: 08/12/2023] [Indexed: 10/05/2023] Open
Abstract
Introducing dental polymers has accelerated biotechnological research, advancing tissue engineering, biomaterials development, and drug delivery. Polymers have been utilized effectively in dentistry to build dentures and orthodontic equipment and are key components in the composition of numerous restorative materials. Furthermore, dental polymers have the potential to be employed for medication administration and tissue regeneration. To analyze the influence of polymer-based investigations on practical medical trials, it is required to evaluate the research undertaken in this sector. The present review aims to gather evidence on polymer applications in dental, oral, and maxillofacial reconstruction.
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Affiliation(s)
- Gamal A Atia
- Department of Oral Medicine, Periodontology, and Diagnosis, Faculty of Dentistry, Suez Canal University, Ismailia, Egypt
| | - Hany K Shalaby
- Department of Oral Medicine, Periodontology and Oral Diagnosis, Faculty of Dentistry, Suez University, Suez, Egypt
| | - Ali B Roomi
- Department of Quality Assurance, University of Thi-Qar, Thi-Qar, Iraq
- Department of Medical Laboratory, College of Health and Medical Technology, National University of Science and Technology, Thi-Qar, Iraq
| | - Mohamed M Ghobashy
- Radiation Research of Polymer Chemistry Department, National Center for Radiation Research and Technology (NCRRT), Atomic Energy Authority, Cairo, Egypt
| | - Hager A Attia
- Department of Molecular Biology and Chemistry, Faculty of Science, Alexandria University, Alexandria, Egypt
| | - Sara Z Mohamed
- Department of Removable Prosthodontics, Faculty of Dentistry, Suez Canal University, Ismailia, Egypt
| | - Ahmed Abdeen
- Department of Forensic Medicine and Toxicology, Faculty of Veterinary Medicine, Benha University, Toukh, Egypt
| | - Mohamed Abdo
- Department of Animal Histology and Anatomy, School of Veterinary Medicine, Badr University in Cairo (BUC), Badr City, Egypt
- Department of Anatomy and Embryology, Faculty of Veterinary Medicine, University of Sadat City, Sadat, Egypt
| | - Liana Fericean
- Department of Biology and Plant Protection, Faculty of Agriculture. University of Life Sciences “King Michael I” from Timișoara, Timișoara, Romania
| | - Ioan Bănățean Dunea
- Department of Biology and Plant Protection, Faculty of Agriculture. University of Life Sciences “King Michael I” from Timișoara, Timișoara, Romania
| | - Ahmed M Atwa
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Egyptian Russian University, Cairo, Egypt
| | - Tabinda Hasan
- Department of Basic Sciences, College of Medicine, Princess Nourah bint Abdulrahman University, Riyadh, Saudi Arabia
| | - Wessam Mady
- Center of Excellence in Genomic Medicine Research, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Afaf Abdelkader
- Department of Forensic Medicine and Clinical Toxicology, Faculty of Medicine, Benha University, Benha, Egypt
| | - Susan A Ali
- Department of Radiodiagnosis, Faculty of Medicine, Ain Shams University, Abbassia, 1181, Egypt
| | - Ola A Habotta
- Department of Forensic Medicine and Toxicology, Faculty of Veterinary Medicine, Mansoura University, Mansoura, Egypt
| | - Rehab A Azouz
- Department of Forensic Medicine and Toxicology, Faculty of Veterinary Medicine, Cairo University, Giza, Egypt
| | - Farag Malhat
- Department of Pesticide Residues and Environmental Pollution, Central Agricultural Pesticide Laboratory, Agricultural Research Center, Giza, Egypt
| | - Mustafa Shukry
- Department of Physiology, Faculty of Veterinary Medicine, Kafrelsheikh University, Kafrelsheikh, Egypt
| | - Tarek Foda
- Oral Health Sciences Department, Temple University’s Kornberg School of Dentistry, Philadelphia, PA, USA
| | - Stefania Dinu
- Department of Pedodontics, Faculty of Dental Medicine, Victor Babes University of Medicine and Pharmacy Timisoara, Timisoara, 300041, Romania
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Efficient controlled release of cannabinoids loaded in γ-CD-MOFs and DPPC liposomes as novel delivery systems in oral health. Mikrochim Acta 2023; 190:125. [PMID: 36894805 PMCID: PMC9998313 DOI: 10.1007/s00604-023-05692-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Accepted: 02/14/2023] [Indexed: 03/11/2023]
Abstract
Olivetol (OLV), as a cannabidiol (CBD) analog, was incorporated in γ-cyclodextrin metal-organic frameworks (γ-CD-MOFs) and 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) liposomes as potential analgesic drug delivery systems (DDS) for dental hypersensitivity (DH) treatment. These DDS have been scarcely employed in oral health, being the first time in case of MOFs loaded with cannabinoids. In vitro experiments using bovine teeth were performed to verify if the drug is able to reach the dentin, where it can flow to the pulp tissues and exert its analgesic effect; enamel and dentin regions were analyzed by synchrotron radiation-based FTIR microspectroscopy. Principal component analysis (PCA) was used to process the spectroscopic data as a powerful chemometric tool, and it revealed a similar behavior in both regions. The studied DDS have been characterized by different techniques, and is was demonstrated that DDS is an efficient way to carry the drug through dental tissues without compromising their structure.
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Biomimetic Mineralization of Tooth Enamel Using Nanocrystalline Hydroxyapatite under Various Dental Surface Pretreatment Conditions. Biomimetics (Basel) 2022; 7:biomimetics7030111. [PMID: 35997431 PMCID: PMC9397024 DOI: 10.3390/biomimetics7030111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2022] [Revised: 08/08/2022] [Accepted: 08/09/2022] [Indexed: 11/17/2022] Open
Abstract
In this report, we demonstrated the formation of a biomimetic mineralizing layer obtained on the surface of dental enamel (biotemplate) using bioinspired nanocrystalline carbonate-substituted calcium hydroxyapatite (ncHAp), whose physical and chemical properties are closest to the natural apatite dental matrix, together with a complex of polyfunctional organic and polar amino acids. Using a set of structural, spectroscopy, and advanced microscopy techniques, we confirmed the formation of a nanosized ncHAp-based mineralized layer, as well as studying its chemical, substructural, and morphological features by means of various methods for the pretreatment of dental enamel. The pretreatment of a biotemplate in an alkaline solution of Ca(OH)2 and an amino acid booster, together with the executed subsequent mineralization with ncHAp, led to the formation of a mineralized layer with homogeneous micromorphology and the preferential orientation of the ncHAp nanocrystals. It was shown that the homogeneous crystallization of hydroxyapatite on the biotemplate surface and binding of individual nanocrystals and agglomerates into a single complex by an amino acid booster resulted in an increase (~15%) in the nanohardness value in the enamel rods area, compared to that of healthy natural enamel. Obtaining a similar hierarchy and cleavage characteristics as natural enamel in the mineralized layer, taking into account the micromorphological features of dental tissue, is an urgent problem for future research.
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Tooth whitening effects on dental enamel, oxidation or reduction? Comparison of physicochemical alterations in bovine enamel using Synchrotron-based Micro-FTIR. Dent Mater 2022; 38:670-679. [DOI: 10.1016/j.dental.2022.02.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 01/10/2022] [Accepted: 02/15/2022] [Indexed: 11/19/2022]
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Li C, Gao Y, Xu Z, Tian Y, Mu H, Yu C, Gao Y, Zhang L. Expression and localization of amelotin, laminin γ2 and odontogenesis-associated phosphoprotein (ODAPH) on the basal lamina and junctional epithelium. J Mol Histol 2021; 53:111-118. [PMID: 34709488 DOI: 10.1007/s10735-021-10026-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 09/24/2021] [Indexed: 11/24/2022]
Abstract
At maturation stage of enamel development, a specialized basal lamina (sBL) was built between ameloblasts and enamel. After the teeth eruption, the ameloblasts transform into the inner cell layer of junctional epithelium. The inner cell layer forms the internal basal lamina of junctional epithelium. However, the composition of the sBL and internal basal lamina was not clarified. The objective of our study was to make a description of the localization of amelotin (AMTN), laminin γ2 (LAMC2) and Odontogenesis-associated phosphoprotein (ODAPH) on the sBL and internal basal lamina. In immunohistochemical study, AMTN, LAMC2 and ODAPH were detected on the sBL at maturation stage. AMTN was also detected in ameloblasts at maturation stage. The expression of AMTN decreased from early-to-late maturation stage. In contrast, the expression of LAMC2 and ODAPH was stable. Immunofluorescence double-staining showed the localization of AMTN was close to enamel surface. However, the localization of ODAPH was close to ameloblasts. LAMC2 and ODAPH were observed on internal basal lamina of junctional epithelium. In contrast, no expression of AMTN was detected on internal basal lamina of junctional epithelium. Our results suggested that ODAPH might participate in enamel maturation and periodontal health, which might provide a better understanding of enamel defects and periodontal disease in clinic.
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Affiliation(s)
- Cong Li
- Institute of Stomatology, Binzhou Medical University, No. 346 Guanhai Street, Yantai, 264003, Shandong, China.,Department of Pediatrics and Preventive Dentistry, Hospital Affiliated to Binzhou Medical University, Binzhou, 256600, Shandong, China
| | - Yan Gao
- Department of Pediatrics and Preventive Dentistry, Hospital Affiliated to Binzhou Medical University, Binzhou, 256600, Shandong, China
| | - Zhenzhen Xu
- Department of Pediatrics and Preventive Dentistry, Hospital Affiliated to Binzhou Medical University, Binzhou, 256600, Shandong, China
| | - Yuan Tian
- Institute of Stomatology, Binzhou Medical University, No. 346 Guanhai Street, Yantai, 264003, Shandong, China.,Department of Pediatrics and Preventive Dentistry, Hospital Affiliated to Binzhou Medical University, Binzhou, 256600, Shandong, China
| | - Haiyu Mu
- Institute of Stomatology, Binzhou Medical University, No. 346 Guanhai Street, Yantai, 264003, Shandong, China.,Department of Pediatrics and Preventive Dentistry, Hospital Affiliated to Binzhou Medical University, Binzhou, 256600, Shandong, China
| | - Cuicui Yu
- Institute of Stomatology, Binzhou Medical University, No. 346 Guanhai Street, Yantai, 264003, Shandong, China.,Department of Pediatrics and Preventive Dentistry, Hospital Affiliated to Binzhou Medical University, Binzhou, 256600, Shandong, China
| | - Yuguang Gao
- Institute of Stomatology, Binzhou Medical University, No. 346 Guanhai Street, Yantai, 264003, Shandong, China. .,Department of Pediatrics and Preventive Dentistry, Hospital Affiliated to Binzhou Medical University, Binzhou, 256600, Shandong, China.
| | - Li Zhang
- Institute of Stomatology, Binzhou Medical University, No. 346 Guanhai Street, Yantai, 264003, Shandong, China. .,Department of Stomatology, Yantai Affiliated Hospital of Binzhou Medical University, No. 717 Jinbu Street, Yantai, 264100, Shandong, China.
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Deniz Y, Aktaş Ç, Misilli T, Çarıkçıoğlu B. Effects of radiotherapeutic X-ray irradiation on cervical enamel. Int J Radiat Biol 2021; 97:1667-1674. [PMID: 34586954 DOI: 10.1080/09553002.2021.1987560] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
PURPOSE Therapeutic radiation used for head and neck cancers mainly affects the cervical region of the tooth. To better understand the impact of therapeutic radiation on tooth, we aimed to examine the crystallinity, micro-morphology, and elemental composition of the cervical inner enamel located adjacent to the dento-enamel junction. MATERIALS AND METHODS Ninety-one specimens obtained from 16 impacted third mandibular molars were randomly divided into seven groups (0, 10, 20, 30, 40, 50, and 60 Gy irradiation groups). Energy-dispersive X-ray spectroscopy (EDX) and scanning electron microscopy (SEM) were performed after the irradiation by 6 MV photon energy. The X-ray diffraction (XRD) were conducted in every group before and after irradiation. Elemental compositions, and Ca/P, P/N, Ca/N atomic ratios were subjected to the Shapiro-Wilk normality test. All of the elements except Mg showed a normal distribution and were compared by the one-way ANOVA. The non-normally distributed Mg data and Ca/P, P/N, and Ca/N ratios were compared by the Kruskal-Wallis test. RESULTS The results showed that widening in the interprismatic spaces were observed in the experimental groups subjected to 30 Gy and the following increased doses. In addition, there were no significant differences in C, O, Ca, P, N percentages between irradiated and non-irradiated groups (p > .05). An increase in atomic ratio of the Mg was detected after samples conducted by 60 Gy radiation dose (p < .05). The stoichiometric Ca/P, Ca/N, and P/N atomic ratios did not change by irradiation (p > .05). The XRD peaks of the inner enamel crystalline phase showed a slight decline in the 60 Gy radiation dose group. CONCLUSION Radiation effects begin to be seen after 30 Gy radiation dose groups. The widen interprismatic spaces seen obviously in 50 Gy and 60 Gy dose groups. Besides Mg ratio showed an increase in the 60 Gy dose group. But it should be thought that radiation caries is a multi-factorial disease that is in collaboration with various radiation-induced side effects.
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Affiliation(s)
- Yeşim Deniz
- Department of Dentomaxillofacial Radiology, Faculty of Dentistry, Çanakkale Onsekiz Mart University, Çanakkale, Turkey
| | - Çağatay Aktaş
- Department of Prosthodontics, Private Dental Clinic, Çanakkale, Turkey
| | - Tuğba Misilli
- Department of Restorative Dentistry, Faculty of Dentistry, Çanakkale Onsekiz Mart University, Çanakkale, Turkey
| | - Burak Çarıkçıoğlu
- Department of Pediatric Dentistry, Faculty of Dentistry, Çanakkale Onsekiz Mart University, Çanakkale, Turkey
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Contessi Negrini N, Angelova Volponi A, Higgins C, Sharpe P, Celiz A. Scaffold-based developmental tissue engineering strategies for ectodermal organ regeneration. Mater Today Bio 2021; 10:100107. [PMID: 33889838 PMCID: PMC8050778 DOI: 10.1016/j.mtbio.2021.100107] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 02/15/2021] [Accepted: 02/27/2021] [Indexed: 12/12/2022] Open
Abstract
Tissue engineering (TE) is a multidisciplinary research field aiming at the regeneration, restoration, or replacement of damaged tissues and organs. Classical TE approaches combine scaffolds, cells and soluble factors to fabricate constructs mimicking the native tissue to be regenerated. However, to date, limited success in clinical translations has been achieved by classical TE approaches, because of the lack of satisfactory biomorphological and biofunctional features of the obtained constructs. Developmental TE has emerged as a novel TE paradigm to obtain tissues and organs with correct biomorphology and biofunctionality by mimicking the morphogenetic processes leading to the tissue/organ generation in the embryo. Ectodermal appendages, for instance, develop in vivo by sequential interactions between epithelium and mesenchyme, in a process known as secondary induction. A fine artificial replication of these complex interactions can potentially lead to the fabrication of the tissues/organs to be regenerated. Successful developmental TE applications have been reported, in vitro and in vivo, for ectodermal appendages such as teeth, hair follicles and glands. Developmental TE strategies require an accurate selection of cell sources, scaffolds and cell culture configurations to allow for the correct replication of the in vivo morphogenetic cues. Herein, we describe and discuss the emergence of this TE paradigm by reviewing the achievements obtained so far in developmental TE 3D scaffolds for teeth, hair follicles, and salivary and lacrimal glands, with particular focus on the selection of biomaterials and cell culture configurations.
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Affiliation(s)
| | - A. Angelova Volponi
- Centre for Craniofacial and Regenerative Biology, King's College London, London, UK
| | - C.A. Higgins
- Department of Bioengineering, Imperial College London, London, UK
| | - P.T. Sharpe
- Centre for Craniofacial and Regenerative Biology, King's College London, London, UK
| | - A.D. Celiz
- Department of Bioengineering, Imperial College London, London, UK
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EMILIN proteins are novel extracellular constituents of the dentin-pulp complex. Sci Rep 2020; 10:15320. [PMID: 32948785 PMCID: PMC7501263 DOI: 10.1038/s41598-020-72123-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Accepted: 07/17/2020] [Indexed: 02/07/2023] Open
Abstract
Odontoblasts and pulp stroma cells are embedded within supramolecular networks of extracellular matrix (ECM). Fibrillin microfibrils and associated proteins are crucial constituents of these networks, serving as contextual scaffolds to regulate tissue development and homeostasis by providing both structural and mechanical properties and sequestering growth factors of the TGF-β superfamily. EMILIN-1, -2, and -3 are microfibril-associated glycoproteins known to modulate cell behaviour, growth factor activity, and ECM assembly. So far their expression in the various cells of the dentin-pulp complex during development, in the adult stage, and during inflammation has not been investigated. Confocal immunofluorescence microscopy and western blot analysis of developing and adult mouse molars and incisors revealed an abundant presence of EMILINs in the entire dental papilla, at early developmental stages. Later in development the signal intensity for EMILIN-3 decreases, while EMILIN-1 and -2 staining appears to increase in the pre-dentin and in the ECM surrounding odontoblasts. Our data also demonstrate new specific interactions of EMILINs with fibulins in the dentin enamel junction. Interestingly, in dentin caries lesions the signal for EMILIN-3 was significantly increased in inflamed odontoblasts. Overall our findings point for the first time to a role of EMILINs in dentinogenesis, pulp biology, and inflammation.
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Scheffel DLS, Cury JA, Tenuta LMA, Scheffel RH, Perez C, Soares DG, Basso FG, Costa CADS, Pashley DH, Hebling J. Proteolytic activity, degradation, and dissolution of primary and permanent teeth. Int J Paediatr Dent 2020; 30:650-659. [PMID: 32077547 DOI: 10.1111/ipd.12632] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Revised: 01/28/2020] [Accepted: 02/12/2020] [Indexed: 11/29/2022]
Abstract
BACKGROUND Primary and permanent teeth composition may influence dissolution and degradation rates. AIM To compare the dissolution and degradation of primary and permanent teeth. DESIGN Enamel and dentin powders were obtained from primary molars and premolars and incubated within different pH buffers. Calcium and inorganic phosphate release was quantified in the buffers by atomic absorption and light spectrophotometry. A colorimetric assay was used to assess the MMP activity of primary dentin (PrD) and permanent dentin (PeD). Collagen degradation was assessed by dry mass loss, change in elastic modulus (E), and ICTP and CTX release. Data were submitted to ANOVA and Tukey's tests (α = 0.05). RESULTS Similar dissolution was found between PrD and PeD after 256 hours. At pH 4.5, enamel released more minerals than dentin whereas at pH 5.5 the inverse result was observed. MMP activity was similar for both substrates. PrD showed higher dry mass loss after 1 week. In general, greater reduction in E was recorded for PrD. Higher quantities of ICTP and CTX were released from PrD after 1 week. CONCLUSIONS Primary and permanent teeth presented similar demineralization rates. Collagen degradation, however, was faster and more substantial for PrD.
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Affiliation(s)
- Debora Lopes Salles Scheffel
- Department of Orthodontics and Pediatric Dentistry, School of Dentistry, São Paulo State University (UNESP), Araraquara, SP, Brazil
| | - Jaime Aparecido Cury
- Department of Physiological Sciences, Piracicaba Dental School, University of Campinas (UNICAMP), Piracicaba, SP, Brazil
| | - Livia Maria Andaló Tenuta
- Department of Physiological Sciences, Piracicaba Dental School, University of Campinas (UNICAMP), Piracicaba, SP, Brazil
| | - Régis Henke Scheffel
- Department of Oral Biology, The Dental College of Georgia, Augusta University, Augusta, GA, USA
| | - Cristina Perez
- Division of Pediatric Dentistry, University of Kentucky, Lexington, KY, USA
| | - Diana Gabriela Soares
- Department of Physiology and Patology, São Paulo State University (UNESP), School of Dentistry, Araraquara, SP, Brazil
| | - Fernanda Gonçalves Basso
- Department of Physiology and Patology, São Paulo State University (UNESP), School of Dentistry, Araraquara, SP, Brazil
| | - Carlos Alberto de Souza Costa
- Department of Physiology and Patology, São Paulo State University (UNESP), School of Dentistry, Araraquara, SP, Brazil
| | - David Henry Pashley
- Department of Oral Biology, The Dental College of Georgia, Augusta University, Augusta, GA, USA
| | - Josimeri Hebling
- Department of Orthodontics and Pediatric Dentistry, School of Dentistry, São Paulo State University (UNESP), Araraquara, SP, Brazil
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Is there evidence for Novamin application in remineralization?: A Systematic review. J Oral Biol Craniofac Res 2020; 10:87-92. [PMID: 32190542 DOI: 10.1016/j.jobcr.2020.01.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Accepted: 01/13/2020] [Indexed: 11/23/2022] Open
Abstract
Background Calcium sodium phosphor-silicate material, a type of bio-glass was originally developed as an implant material to regenerate bone and recently adapted for use in oral care products (NovaMin Technology Inc.). Novamin is used for many dental problems like hypersensitivity, gingivitis, bleeding, non-carious lesions, carious lesions, whitening and is currently emerging as one of the treatment modality for the remineralization of the tooth. Since the prescription of these novel materials to the patients are based on cost effectiveness, efficacy and effectiveness, a clinician should make decision based on best available evidence. Hence, the objective of this review is to find out the current evidence available on the use of Novamin as an agent for remineralization. Materials and methods Relevant articles were searched and screened from several databases including PubMed, Cochrane review, Science Direct and trip which were published till 1988 to July 2017; The articles relevant to the objective of this review were included (RCT's) and articles out of interest of this review were excluded. The primary outcome for the chosen studies is the remineralization capacity of Novamin. Data extraction is done independently and jointly by 3 authors using data collection forms. Studies obtained were evaluated using the Cochrane Collaboration tools for accessing risk bias. The assessment of the quality of the evidence and the bias risk was obtained using the Grading of Recommendations Assessment Development and evaluation System. Results The articles from the database obtained for further review was N = 1. According to the study reviewed, the baseline comparisons using decalcification index obtained between Novamin study group (ReNew) and the control group (Crest) yield a P-value of 0.97 whereas after a 3 months interval follow up the value is 0.0403 suggesting there was a trend towards improvement in white spot lesions in the control group and at 6 months' time point the p-value is 0.81 concluding that there are no significant difference of remineralization process obtained by using traditional toothpaste and Novamin. Conclusion Review shows that Novamin has significantly less clinical evidence to prove its effectiveness as a remineralization agent in treating both carious and non-carious lesion. Hence, better designed clinical trials should be carried out in the future before definitive recommendations can be made.
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Fonseca JM, Troconis CC, Palmier NR, Gomes-Silva W, Paglioni MD, Araújo AL, Arboleda LP, Filho AJ, González-Arriagada WA, Goes MF, Lopes MA, Brandão TB, Vargas PA, Ribeiro AC, Santos-Silva AR. The impact of head and neck radiotherapy on the dentine-enamel junction: a systematic review. Med Oral Patol Oral Cir Bucal 2020; 25:e96-e105. [PMID: 31880287 PMCID: PMC6982993 DOI: 10.4317/medoral.23212] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Accepted: 10/30/2019] [Indexed: 11/18/2022] Open
Abstract
Background Radiotherapy is widely used in contemporary head and neck cancer treatment protocols. The ability of head and neck radiotherapy (HNRT) to cause direct radiogenic destruction to the teeth is one of the most controversial topics in the field of oral oncology. Therefore, this systematic review aimed to investigate ionising radiation as an independent factor for physical and chemical changes on the dentine-enamel junction (DEJ), a pivotal dental topography for the onset and progression of radiation-related caries (RRC) and enamel delamination.
Material and Methods Systematic searches were conducted on three databases: Scopus, MEDLINE (Via PubMed) and Embase (Elsevier). Laboratory studies evaluating the effects of simulated or in vivo HNRT on the DEJ were included. The GRADE tool adapted for in vitro studies was used to assess the methodological quality.
Results Of the 154 initially selected studies, eight met the inclusion criteria, from which five studies were graded as high quality of evidence, two studies were graded as moderate quality and one as low quality. Two studies did not demonstrate DEJ alterations following HNRT while the other six articles described several organic and inorganic changes in the DEJ of irradiated teeth samples. These radiogenic events were mostly detected through micro and nanoindentation, Raman micro-spectroscopy, confocal microscopy, Western blotting and optical coherence tomography.
Conclusions HNRT may have a negative impact on the physical and chemical aspects of the DEJ, predisposing cancer patients to RRC and enamel delamination. Key words:Cancer, radiotherapy, radiation-related caries, dentin-enamel junction, systematic review.
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Affiliation(s)
- J-M Fonseca
- Oral Diagnosis Department, Semiology Area Piracicaba Dental School, UNICAMP, Brazil 901, Av. Limeira, Areão, Piracicaba, São Paulo - Brazil Postal code: 13414- 903
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13
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Kudkuli J, Abdulla R, Rekha P, Sharma S, Gurjar O. Spectroscopic analyses reveal radiotherapy-induced variations in elemental composition and crystallite properties of human permanent teeth enamel. J Oral Biosci 2019; 61:207-214. [DOI: 10.1016/j.job.2019.10.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Revised: 09/26/2019] [Accepted: 10/02/2019] [Indexed: 11/16/2022]
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14
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Jágr M, Ergang P, Pataridis S, Kolrosová M, Bartoš M, Mikšík I. Proteomic analysis of dentin-enamel junction and adjacent protein-containing enamel matrix layer of healthy human molar teeth. Eur J Oral Sci 2018; 127:112-121. [DOI: 10.1111/eos.12594] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/22/2018] [Indexed: 11/29/2022]
Affiliation(s)
- Michal Jágr
- Institute of Physiology; The Czech Academy of Sciences; Prague Czech Republic
- Quality of Plant Products; Crop Research Institute; Prague Czech Republic
| | - Peter Ergang
- Institute of Physiology; The Czech Academy of Sciences; Prague Czech Republic
| | - Statis Pataridis
- Institute of Physiology; The Czech Academy of Sciences; Prague Czech Republic
| | - Marta Kolrosová
- Department of Analytical Chemistry; Faculty of Science; Charles University; Prague Czech Republic
| | - Martin Bartoš
- Institute of Dental Medicine; First Faculty of Medicine; Charles University and General University Hospital; Prague Czech Republic
| | - Ivan Mikšík
- Institute of Physiology; The Czech Academy of Sciences; Prague Czech Republic
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15
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Chang B, Svoboda KKH, Liu X. Cell polarization: From epithelial cells to odontoblasts. Eur J Cell Biol 2018; 98:1-11. [PMID: 30473389 DOI: 10.1016/j.ejcb.2018.11.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Revised: 10/04/2018] [Accepted: 11/16/2018] [Indexed: 12/29/2022] Open
Abstract
Cell polarity identifies the asymmetry of a cell. Various types of cells, including odontoblasts and epithelial cells, polarize to fulfil their destined functions. Odontoblast polarization is a prerequisite and fundamental step for tooth development and tubular dentin formation. Current knowledge of odontoblast polarization, however, is very limited, which greatly impedes the development of novel approaches for regenerative endodontics. Compared to odontoblasts, epithelial cell polarization has been extensively studied over the last several decades. The knowledge obtained from epithelia polarization has been found applicable to other cell types, which is particularly useful considering the remarkable similarities of the morphological and compositional features between polarized odontoblasts and epithelia. In this review, we first discuss the characteristics, the key regulatory factors, and the process of epithelial polarity. Next, we compare the known facts of odontoblast polarization with epithelial cells. Lastly, we clarify knowledge gaps in odontoblast polarization and propose the directions for future research to fill the gaps, leading to the advancement of regenerative endodontics.
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Affiliation(s)
- Bei Chang
- Department of Biomedical Sciences, Texas A&M University College of Dentistry, Dallas, TX, 75246, USA
| | - Kathy K H Svoboda
- Department of Biomedical Sciences, Texas A&M University College of Dentistry, Dallas, TX, 75246, USA
| | - Xiaohua Liu
- Department of Biomedical Sciences, Texas A&M University College of Dentistry, Dallas, TX, 75246, USA.
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16
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Seyedmahmoud R, Wang Y, Thiagarajan G, Gorski JP, Reed Edwards R, McGuire JD, Walker MP. Oral cancer radiotherapy affects enamel microhardness and associated indentation pattern morphology. Clin Oral Investig 2018; 22:1795-1803. [PMID: 29151196 PMCID: PMC5908727 DOI: 10.1007/s00784-017-2275-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Accepted: 11/13/2017] [Indexed: 11/25/2022]
Abstract
OBJECTIVES The aim of this study is to determine the effects of in vitro and in vivo high-dose radiotherapy on microhardness and associated indentation pattern morphology of enamel. MATERIALS AND METHODS The inner, middle, and outer microhardness of enamel was evaluated using three experimental groups: control (non-radiated); in vitro irradiated; in vivo irradiated. In vitro specimens were exposed to simulated radiotherapy, and in vivo specimens were extracted teeth from oral cancer patients previously treated with radiotherapy. Indentations were measured via SEM images to calculate microhardness values and to assess the mechanomorphological properties of enamel before and after radiotherapy. RESULTS Middle and outer regions of enamel demonstrated a significant decrease in microhardness after in vitro and in vivo irradiation compared to the control group (p < 0.05). Two indentation patterns were observed: pattern A-presence of microcracks around indent periphery, which represents local dissipation of deformation energy; pattern B-clean, sharp indents. The percentage of clean microindentation patterns, compared to controls, was significantly higher following in vitro and in vivo irradiation in all enamel regions. The highest percentage of clean microindentations (65%) was observed in the in vivo irradiated group in the inner region of enamel near the dentin-enamel junction. CONCLUSIONS For the first time, this study shows that in vitro and in vivo irradiation alters enamel microhardness. Likewise, the indentation pattern differences suggest that enamel may become more brittle following in vitro and in vivo irradiation. CLINICAL RELEVANCE The mechanomorphological property changes of enamel following radiation may be a contributory component of pathologic enamel delamination following oral cancer radiotherapy.
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Affiliation(s)
- R Seyedmahmoud
- Department of Oral and Craniofacial Sciences, School of Dentistry, University of Missouri-Kansas City, 650 East 25th St, Kansas City, MO, 64108, USA
| | - Y Wang
- Department of Oral and Craniofacial Sciences, School of Dentistry, University of Missouri-Kansas City, 650 East 25th St, Kansas City, MO, 64108, USA.
- Center of Excellence in Musculoskeletal and Dental Tissues, University of Missouri-Kansas City, 650 East 25th St, Kansas City, MO, 64108, USA.
| | - G Thiagarajan
- Department of Oral and Craniofacial Sciences, School of Dentistry, University of Missouri-Kansas City, 650 East 25th St, Kansas City, MO, 64108, USA
- Department of Civil and Mechanical Engineering, School of Computing and Engineering, University of Missouri-Kansas City, Kansas City, MO, USA
| | - J P Gorski
- Department of Oral and Craniofacial Sciences, School of Dentistry, University of Missouri-Kansas City, 650 East 25th St, Kansas City, MO, 64108, USA
- Center of Excellence in Musculoskeletal and Dental Tissues, University of Missouri-Kansas City, 650 East 25th St, Kansas City, MO, 64108, USA
| | - R Reed Edwards
- Department of Oral and Craniofacial Sciences, School of Dentistry, University of Missouri-Kansas City, 650 East 25th St, Kansas City, MO, 64108, USA
| | - J D McGuire
- Department of Oral and Craniofacial Sciences, School of Dentistry, University of Missouri-Kansas City, 650 East 25th St, Kansas City, MO, 64108, USA
| | - M P Walker
- Department of Oral and Craniofacial Sciences, School of Dentistry, University of Missouri-Kansas City, 650 East 25th St, Kansas City, MO, 64108, USA.
- Center of Excellence in Musculoskeletal and Dental Tissues, University of Missouri-Kansas City, 650 East 25th St, Kansas City, MO, 64108, USA.
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17
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Abstract
The basement membrane is a thin but dense, sheet-like specialized type of extracellular matrix that has remarkably diverse functions tailored to individual tissues and organs. Tightly controlled spatial and temporal changes in its composition and structure contribute to the diversity of basement membrane functions. These different basement membranes undergo dynamic transformations throughout animal life, most notably during development. Numerous developmental mechanisms are regulated or mediated by basement membranes, often by a combination of molecular and mechanical processes. A particularly important process involves cell transmigration through a basement membrane because of its link to cell invasion in disease. While developmental and disease processes share some similarities, what clearly distinguishes the two is dysregulation of cells and extracellular matrices in disease. With its relevance to many developmental and disease processes, the basement membrane is a vitally important area of research that may provide novel insights into biological mechanisms and development of innovative therapeutic approaches. Here we present a review of developmental and disease dynamics of basement membranes in Caenorhabditis elegans, Drosophila, and vertebrates.
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18
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Fouillen A, Dos Santos Neves J, Mary C, Castonguay JD, Moffatt P, Baron C, Nanci A. Interactions of AMTN, ODAM and SCPPPQ1 proteins of a specialized basal lamina that attaches epithelial cells to tooth mineral. Sci Rep 2017; 7:46683. [PMID: 28436474 PMCID: PMC5402393 DOI: 10.1038/srep46683] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Accepted: 03/24/2017] [Indexed: 12/25/2022] Open
Abstract
A specialized basal lamina (sBL) mediates adhesion of certain epithelial cells to the tooth. It is distinct because it does not contain collagens type IV and VII, is enriched in laminin-332, and includes three novel constituents called amelotin (AMTN), odontogenic ameloblast-associated (ODAM), and secretory calcium-binding phosphoprotein proline-glutamine rich 1 (SCPPPQ1). The objective of this study was to clarify the structural organization of the sBL. Fluorescence and immunogold labeling showed that the three proteins co-localize. Quantitative analysis of the relative position of gold particles on the sBL demonstrates that the distribution of ODAM is skewed towards the cell while that of AMTN and SCPPPQ1 tends towards the tooth surface. Bacterial two-hybrid analysis and co-immunoprecipitation, gel filtration of purified proteins and transmission electron and atomic force microscopies highlight the propensity of AMTN, ODAM, and SCPPPQ1 to interact with and among themselves and form supramolecular aggregates. These data suggest that AMTN, ODAM and SCPPPQ1 participate in structuring an extracellular matrix with the distinctive capacity of attaching epithelial cells to mineralized surfaces. This unique feature is particularly relevant for the adhesion of gingival epithelial cells to the tooth surface, which forms a protective seal that is the first line of defense against bacterial invasion.
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Affiliation(s)
- Aurélien Fouillen
- Laboratory for the Study of Calcified Tissues and Biomaterials, Department of Stomatology, Faculty of Dental medicine Université de Montréal, Montréal, Québec, Canada.,Department of Biochemistry and Molecular Medicine, Faculty of Medicine, Université de Montréal, Québec, Canada
| | - Juliana Dos Santos Neves
- Laboratory for the Study of Calcified Tissues and Biomaterials, Department of Stomatology, Faculty of Dental medicine Université de Montréal, Montréal, Québec, Canada
| | - Charline Mary
- Department of Biochemistry and Molecular Medicine, Faculty of Medicine, Université de Montréal, Québec, Canada
| | - Jean-Daniel Castonguay
- Laboratory for the Study of Calcified Tissues and Biomaterials, Department of Stomatology, Faculty of Dental medicine Université de Montréal, Montréal, Québec, Canada
| | - Pierre Moffatt
- Shriners Hospital for Children, Montréal, Québec, Canada
| | - Christian Baron
- Department of Biochemistry and Molecular Medicine, Faculty of Medicine, Université de Montréal, Québec, Canada
| | - Antonio Nanci
- Laboratory for the Study of Calcified Tissues and Biomaterials, Department of Stomatology, Faculty of Dental medicine Université de Montréal, Montréal, Québec, Canada.,Department of Biochemistry and Molecular Medicine, Faculty of Medicine, Université de Montréal, Québec, Canada
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19
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Gomes-Silva W, Prado-Ribeiro AC, Brandão TB, Morais-Faria K, de Castro Junior G, Mak MP, Lopes MA, Rocha MM, Salo T, Tjäderhane L, de Goes MF, Santos-Silva AR. Postradiation Matrix Metalloproteinase-20 Expression and Its Impact on Dental Micromorphology and Radiation-Related Caries. Caries Res 2017; 51:216-224. [DOI: 10.1159/000457806] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Accepted: 01/16/2017] [Indexed: 11/19/2022] Open
Abstract
Recent evidence suggests that head-and-neck radiotherapy (HNRT) increases active forms of matrix metalloproteinase-20 (MMP-20) in human tooth crowns, degrading the dentin-enamel junction (DEJ) and leading to enamel delamination, which is a pivotal step in the formation of radiation-related caries (RRC). Additional participation of enzymatic degradation of organic matrix components in caries progression was attributed to MMP-20 in dentin. Therefore, the current study tested the hypothesis that MMP-20 is overexpressed in the DEJ, dentin-pulp complex components, and carious dentin of post-HNRT patients, leading to detectable micromorphological changes to the enamel and dentin. Thirty-six teeth were studied, including 19 post-HNRT specimens and 17 nonirradiated controls. Optical light microscopy was used to investigate the micromorphological components of the DEJ, dentin-pulp complex components, and carious dentin. The samples were divided into 2 subgroups: nondemineralized ground sections (n = 20) and demineralized histological sections (n = 16). In addition, immunohistochemical analysis using the immunoperoxidase technique was conducted to semiquantitatively assess MMP-20 expression in the DEJ, dentin-pulp complex components, and carious dentin. No apparent damage to the DEJ microstructure or other dentin-pulp complex components was observed and no statistically significant differences were detected in MMP-20 expression (p > 0.05) between the irradiated and control groups. This study rejected the hypothesis that MMP-20 is overexpressed in the DEJ, dentin-pulp complex components, and carious dentin of post-HNRT patients, leading to detectable micromorphological changes. Hence, direct effects of radiation may not be regarded as an independent factor to explain aggressive clinical patterns of RRC.
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20
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Wazen RM, Viegas-Costa LC, Fouillen A, Moffatt P, Adair-Kirk TL, Senior RM, Nanci A. Laminin γ2 knockout mice rescued with the human protein exhibit enamel maturation defects. Matrix Biol 2016; 52-54:207-218. [PMID: 26956061 DOI: 10.1016/j.matbio.2016.03.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Revised: 03/03/2016] [Accepted: 03/03/2016] [Indexed: 01/13/2023]
Abstract
The epithelial ameloblasts are separated from the maturing enamel by an atypical basement membrane (BM) that is enriched in laminin 332 (LM-332). This heterotrimeric protein (α3, ß3 and γ2 chains) provides structural integrity to BMs and influences various epithelial cell processes including cell adhesion and differentiation. Mouse models that lack expression of individual LM-332 chains die shortly after birth. The lethal phenotype of laminin γ2 knockout mice can be rescued by human laminin γ2 (LAMC2) expressed using a doxycycline-inducible (Tet-on) cytokeratin 14 promoter-rtTA. These otherwise normal-looking rescued mice exhibit white spot lesions on incisors. We therefore investigated the effect of rescue with human LAMC2 on enamel maturation and structuring of the atypical BM. The maturation stage enamel organ in transgenic mice was severely altered as compared to wild type controls, a structured BM was no longer discernible, dystrophic matrix appeared in the maturing enamel layer, and there was residual enamel matrix late into the maturation stage. Microtomographic scans revealed excessive wear of occlusal surfaces on molars, chipping of enamel on incisor tips, and hypomineralization of the enamel layer. No structural alterations were observed at other epithelial sites, such as skin, palate and tongue. These results indicate that while this humanized mouse model is capable of rescue in various epithelial tissues, it is unable to sustain structuring of a proper BM at the interface between ameloblasts and maturing enamel. This failure may be related to the atypical composition of the BM in the maturation stage and reaffirms that the atypical BM is essential for enamel maturation.
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Affiliation(s)
- Rima M Wazen
- Laboratory for the Study of Calcified Tissues and Biomaterials, Department of Stomatology, Faculty of Dentistry, Université de Montréal, Montréal, Québec, Canada
| | - Luiz C Viegas-Costa
- Laboratory for the Study of Calcified Tissues and Biomaterials, Department of Stomatology, Faculty of Dentistry, Université de Montréal, Montréal, Québec, Canada
| | - Aurélien Fouillen
- Laboratory for the Study of Calcified Tissues and Biomaterials, Department of Stomatology, Faculty of Dentistry, Université de Montréal, Montréal, Québec, Canada; Department of Biochemistry and Molecular Medicine, Université de Montréal, Montréal, Québec, Canada
| | - Pierre Moffatt
- Shriners Hospital for Children, Montréal, Montréal, Québec, Canada
| | - Tracy L Adair-Kirk
- Department of Medicine, Washington University School of Medicine, St. Louis, MO
| | - Robert M Senior
- Department of Medicine, Washington University School of Medicine, St. Louis, MO
| | - Antonio Nanci
- Laboratory for the Study of Calcified Tissues and Biomaterials, Department of Stomatology, Faculty of Dentistry, Université de Montréal, Montréal, Québec, Canada; Department of Biochemistry and Molecular Medicine, Université de Montréal, Montréal, Québec, Canada.
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