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Archives of Oral Biology Dec 2022This systematic review examines the effect of age on changes to coronal dentin properties. (Review)
Review
OBJECTIVE
This systematic review examines the effect of age on changes to coronal dentin properties.
DESIGN
Pubmed, Cinhal, Scopus, Web of Science and the Cochrane Database were searched for publications up to 31 December 2021. All studies were uploaded and reviewed using Covidence software. At different stages of the review, study selection and the extraction of data were completed by six independent reviewers based on the eligibility criteria. The quality of the articles was judged based on JBI Critical Appraisal Checklist for quasi-experimental studies.
RESULTS
Twelve studies satisfied the eligibility criteria and were included. Dentin characteristics and mechanical properties alter with age, and spatially within a tooth to depend on tubule orientation. Age-related mineral deposition within tubules, and collagen maturation in intertubular dentin compound the spatial effects on mechanical properties. Mechanical properties depend on collagen fiber orientation and apatite alignment relative to dentin tubules, characteristic differences in peritubular and intertubular dentin, and relative dentin tubule distribution within a tooth. The bulk of the research focussed on age-related apatite effects, although many reported limited understanding of changes to collagen, particularly in intertubular dentin.
CONCLUSION
Investigations into the effect of age, depth, site and location on dentin collagen are warranted to minimize tooth loss in older populations by providing targeted adhesive, restorative or preventative interventions.
Topics: Adult; Humans; Aged; Dentin; Tooth; Collagen; Apatites; Minerals
PubMed: 36182707
DOI: 10.1016/j.archoralbio.2022.105553 -
Scientific Reports Jul 2023According to the previous studies of sialolithiasis reported so far, this study is aimed to identify the biological components of sialolith, which show different...
According to the previous studies of sialolithiasis reported so far, this study is aimed to identify the biological components of sialolith, which show different ultrastructures and chemical compositions from other stones, cholelith and urolith. Twenty-two specimens obtained from 20 patients were examined histologically, and analyzed with micro-CT, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and transmission electron microscopy (TEM). All sialoliths (n = 22) observed in this study showed a central nidus, which was filled with organoid matrix admixed with exosome vesicles, loose calcium apatite crystals, and many bacteria. The micro-CT and SEM observation clearly defined a single or multiple central nidus(es) encircled by highly calcified compact zone. The circular compact zone showed a band-like calcification, about 1-3 mm in thickness, and usually located between the central nidus and the peripheral multilayer zone. But some sialoliths (n = 5) showed severe erosion of compact zone by expanding multilayered zone depending on the level of calcification and inflammation in sialolith. By observing TEM images, many exosome vesicles and degraded cytoplasmic organelles were found in the central nidus, and some epithelial cells were also found in the calcified matrix of peripheral multilayer zone. Particularly, EDS analysis indicated the highest Ca/P ratio in the intermediate compact zone (1.77), and followed by the central nidus area (1.39) and the peripheral multilayer zone (0.87). Taken together, these data suggest that the central nidus containing many inflammatory exosomes and degraded cytoplasmic organelles has a potential to induce a band-like calcification of compact zone, and followed by the additional multilayer deposition of exfoliated salivary epithelial cells as well as salivary materials. Thereby, the calcium apatite-based sialolith is gradually growing in its volume size, and eventually obstructs the salivary flow and provides a site for the bacterial infection.
Topics: Humans; Salivary Gland Calculi; Calcium; Microscopy, Electron, Scanning; Microscopy, Electron, Transmission; Calcinosis; Apatites
PubMed: 37507401
DOI: 10.1038/s41598-023-37462-w -
Journal of Oral Biosciences Jun 2022Development of new clinical regenerative procedures is needed for the reconstruction of the connective tissue attachment lost to periodontal disease. Apatite coating on... (Review)
Review
BACKGROUND
Development of new clinical regenerative procedures is needed for the reconstruction of the connective tissue attachment lost to periodontal disease. Apatite coating on the affected root surfaces could improve root surface biocompatibility and promote the reestablishment of connective tissue attachment.
HIGHLIGHT
We developed two novel techniques that use laser light for coating the tooth surface with apatite. In the laser-assisted biomimetic (LAB) process, a tooth substrate was placed in a supersaturated calcium phosphate solution and irradiated for 30 min with low-energy pulsed laser light. Due to the laser-assisted pseudo-biomineralization, a submicron-thick apatite film was created on the laser-irradiated tooth surface. Furthermore, we created a fluoride-incorporated apatite film on the tooth surface using the LAB process and demonstrated its antibacterial activity against Streptococcus mutans. In the laser-induced forward transfer with optical stamp (LIFTOP) process, a thin apatite film loaded with the cell-adhesion protein, fibronectin, was prepared beforehand as a raw material on the optical stamp (carbon- and polydimethylsiloxane-coated support) by a conventional biomimetic process. After irradiation with a single laser pulse, the film (microchip) was transferred onto a tooth substrate via laser ablation of the carbon sacrificial layer. The LIFTOP process requires only a short processing time and has a minimal heat effect on the film; thus, the film exhibits cell adhesion activity even after the LIFTOP process.
CONCLUSION
The LAB and LIFTOP processes have the potential as novel tools for tooth surface modification in the treatment of periodontal disease.
Topics: Apatites; Carbon; Humans; Lasers; Periodontal Diseases; Surface Properties
PubMed: 35351642
DOI: 10.1016/j.job.2022.03.004 -
Scientific Reports Jun 2023Micro-Raman spectra of concretions with and without fossils were measured in a nondestructive manner. The band position and full width at half maximum height (FWHM) of...
Micro-Raman spectra of concretions with and without fossils were measured in a nondestructive manner. The band position and full width at half maximum height (FWHM) of ν-PO of apatite in the concretions were analyzed to investigate the origin of apatite. The analyzed concretions were derived from the Kita-ama Formation of the Izumi Group, Japan. The micro-Raman analysis showed that the apatites in the concretions were divided into two groups: Group W (wide FWHM group) and Group N (narrow FWHM group). The apatite belonging to Group W is suggested to be biogenic apatite originating from the soft body tissues of organisms because the Sr content is high and the FWHM is similar to that of apatite in bones and teeth of present-day animals. The other apatite belonging to Group N is considered affected by the diagenetic process because of its narrow FWHM and F substitution. These features of both groups were observed regardless of the presence of fossils or absence of fossils in the concretions. This Raman spectroscopic study suggests that the apatite at the time of concretion formation belonged to Group W but was changed to Group N by the substitution of F during the diagenesis process.
Topics: Animals; Apatites; Fossils; Spectrum Analysis, Raman; Carbonates; Bone and Bones
PubMed: 37322242
DOI: 10.1038/s41598-023-36566-7 -
Scientific Reports Nov 2023The need for bioactive and non-toxic biomaterials is on a high demand in tissue engineering applications nowadays. Hydroxyapatite (HAp) is the chief constituent of teeth...
The need for bioactive and non-toxic biomaterials is on a high demand in tissue engineering applications nowadays. Hydroxyapatite (HAp) is the chief constituent of teeth and bones in mammas. One of the major challenges with the use of HAp in engineering application is its brittleness and to overcome this, it's important to react it with a material that can enhanced it's fragility. To this end, HAp and HAp/clay nanocomposites were developed via wet chemical process to mimic natural HAp and to equally confer special properties such as mechanical properties, high surface area, crystallinity, high porosity, and biocompatibility on the biomaterial. The functional groups properties of the as-prepared nanocomposites analyzed by FT-IR showed that the HAp and clay posed reactive centers such as Al-Al-OH, Si-Si-OH, Si-O, PO, -OH, and Si-O-Al. The XRD results confirmed the formation of HAp/clay nanocomposite, while SEM and TEM images showed the morphologies of the prepared nanocomposites to be round shape particles. Besides, EDX result revealed the Ca/P ratio of HAp and HAp-C to be lower than that of stoichiometric ratio (1.67) which implies the presence of K, Na, Ca, Mg, Si and Al in the HAp/clay nanocomposite. The mechanical properties of the apatite were greatly enhanced by the addition of clay. The physiological behaviour of the fabricated apatite composites in saline solution showed steady increase in the values of the saline pH of the various biomolecules until day 5 and became fairly constant at day 7 with pH range of 7.30-7.38. Though the saline solution was acidic at the beginning due to dissolved carbon dioxide, the pH of the saline solution containing the nanocomposites gradually became neutral and fairly alkaline over time as a result of the presence of Lewis basis structures in the composites which helps in neutralizing the acidic solution. Furthermore, proliferation of apatites particles onto the surface of the nanocomposites was observed after treatment with simulated body fluids (SBF) media for 7 days. Thus, HAp/clay nanocomposites can be useful biomaterials in bone tissue engineering.
Topics: Durapatite; Clay; Spectroscopy, Fourier Transform Infrared; Saline Solution; Biocompatible Materials; Nanocomposites; Apatites
PubMed: 37963905
DOI: 10.1038/s41598-023-45646-7 -
BioMed Research International 2013Biological apatite is an inorganic calcium phosphate salt in apatite form and nano size with a biological derivation. It is also the main inorganic component of... (Review)
Review
Biological apatite is an inorganic calcium phosphate salt in apatite form and nano size with a biological derivation. It is also the main inorganic component of biological hard tissues such as bones and teeth of vertebrates. Consequently, biological apatite has a wide application in dentistry and orthopedics by using as dental fillers and bone substitutes for bone reconstruction and regeneration. Given this, it is of great significance to obtain a comprehensive understanding of its physiochemical and biological properties. However, upon the previous studies, inconsistent and inadequate data of such basic properties as the morphology, crystal size, chemical compositions, and solubility of biological apatite were reported. This may be ascribed to the differences in the source of raw materials that biological apatite are made from, as well as the effect of the preparation approaches. Hence, this paper is to provide some insights rather than a thorough review of the physiochemical properties as well as the advantages and drawbacks of various preparation methods of biological apatite.
Topics: Apatites; Biocompatible Materials; Chemical Phenomena; Humans
PubMed: 24078928
DOI: 10.1155/2013/929748 -
Urolithiasis Feb 2017How stones are retained within the kidney while small in size is still not fully understood. In this paper, we show two examples of how stones are retained during early... (Review)
Review
How stones are retained within the kidney while small in size is still not fully understood. In this paper, we show two examples of how stones are retained during early growth: one is growth on Randall's (interstitial) plaque, and the other is growth on mineral that has formed as a luminal plug in a terminal collecting duct. These two mechanisms of stone retention during early growth have distinctive morphologic features that can be seen by methods that show the microscopic structure of the stones. Stones growing on Randall's plaque display an apatite region that is typically not large in size (<0.5 mm across) but which usually shows luminal spaces, which are signs of its origin in the connective tissue of the papilla. Stones growing on ductal plugs also show attachment to a piece of apatite, but the apatite regions are typically larger (often >1 mm long and >0.5 mm wide), and they are solid, without spaces running through them. We propose that knowing the mechanisms of stone retention during early stone formation could allow for better treatment of stone diseases.
Topics: Apatites; Crystallization; Humans; Kidney Calculi
PubMed: 27913855
DOI: 10.1007/s00240-016-0944-z -
Anatomical Record (Hoboken, N.J. : 2007) Dec 2021Tooth plates are a unique dental organ found in holocephalan fishes and lungfish. The chimaeroid tooth plates are atypical in terms of biomineralization, due to the hard...
Tooth plates are a unique dental organ found in holocephalan fishes and lungfish. The chimaeroid tooth plates are atypical in terms of biomineralization, due to the hard tissue composition of whitlockite and apatite, while those of lungfish and other vertebrates are composed of apatite. The tooth plates are overlaid by a thin veneer-outer dentin-whose composition and role are not known. We aimed to test whether the outer dentin is composed of whitlockite or apatite, and whether it protects the osteodentin from abrasion and supports its overall strength. For this purpose, the mineral components and microstructure of outer dentin were studied. Our analyses of the outer dentin from the anterior (vomerine) tooth plates of Chimaera phantasma revealed that the mineral component is magnesium- and carbonate-containing calcium-deficient apatite and that the outer dentin has a three-zone structure. The main body is sandwiched between thin zones, which are less mineralized than the main body. Furthermore, in the outer zone and the main body, a higher-order structure was formed in accordance with the organization of wide and narrow fibers. Mineralization made the main body a composite of bundles of fibers and apatite. Transmission electron microscopy showed a structural relationship between apatite and the fibrous component on which the apatite was formed. Such a structure of the main body could be highly effective as a framework to resist abrasion and support the overall strength of the tooth plate.
Topics: Animals; Apatites; Dentin; Fishes; Minerals; Tooth
PubMed: 33620142
DOI: 10.1002/ar.24606 -
Journal of Prosthodontic Research Oct 2017The aim of this study was to present the current concept of bone quality based on the proposal by the National Institutes of Health (NIH) and some of the cellular and... (Review)
Review
PURPOSE
The aim of this study was to present the current concept of bone quality based on the proposal by the National Institutes of Health (NIH) and some of the cellular and molecular factors that affect bone quality.
STUDY SELECTION
This is a literature review which focuses on collagen, biological apatite (BAp), and bone cells such as osteoblasts and osteocytes.
RESULTS
In dentistry, the term "bone quality" has long been considered to be synonymous with bone mineral density (BMD) based on radiographic and sensible evaluations. In 2000, the NIH proposed the concept of bone quality as "the sum of all characteristics of bone that influence the bone's resistance to fracture," which is completely independent of BMD. The NIH defines bone quality as comprising bone architecture, bone turnover, bone mineralization, and micro-damage accumulation. Moreover, our investigations have demonstrated that BAp, collagen, and bone cells such as osteoblasts and osteocytes play essential roles in controlling the current concept of bone quality in bone around hip and dental implants.
CONCLUSION
The current concept of bone quality is crucial for understanding bone mechanical functions. BAp, collagen and osteocytes are the main factors affecting bone quality. Moreover, mechanical loading dynamically adapts bone quality. Understanding the current concept of bone quality is required in dentistry.
Topics: Apatites; Bone Density; Bone and Bones; Collagen; Dental Implants; Dentistry; Humans; Osteoblasts; Osteoclasts; Prosthodontics
PubMed: 28633987
DOI: 10.1016/j.jpor.2017.05.006 -
Acta Biomaterialia Jan 2021The occurrence of an amorphous calcium phosphate layer covering the crystalline apatite core has been suggested to be an intrinsic feature of both bone mineral and...
The occurrence of an amorphous calcium phosphate layer covering the crystalline apatite core has been suggested to be an intrinsic feature of both bone mineral and synthetic biomimetic analogs. However, an exahustive quantitative picture of the amorphous-crystalline relationship in these materials is still missing. Here, we present a multiple scale modelling that combines small-angle X-ray scattering (SAXS) and synchrotron wide-angle X-ray total scattering (WAXTS) analyses to investigate the amorphous-crystalline spatial interplay in bone sample and biomimetic carbonated nano-apatites. SAXS analysis indicates the presence of a single morphology consisting of tiny nanoplates (NPLs) and provides a measure of their thickness (falling in the 3-5 nm range). WAXTS analysis was performed by developing atomistic models of apatite NPLs incorporating lattice strain, mostly attributed to the carbonate content, and calculating the X-ray patterns using the Debye Scattering Equation. Upon model optimization, the size and strain parameters of the crystalline platelets were derived and the amorphous component, co-existing with the crystalline one, separated and quantified (in the 23-33 wt% range). Notably, the thickness of the apatite core was found to exhibit nearly null (bone) or minor (< 0.5 nm, biomimetic samples) deviations from that of the entire NPLs, suggesting that the amorphous material remains predominantly distributed along the lateral sides of the NPLs, in a core-crown-like arrangement. The lattice strain analysis indicates a significant stiffness along the c axis, which is comparable in bone and synthetic samples, and larger deformations in the other directions. STATEMENT OF SIGNIFICANCE: Current models of bone mineral and biomimetic nanoapatites suggest the occurrence of an amorphous layer covering the apatitic crystalline nanoplates in a core-shell arrangement. By combining X-ray scattering techniques in the small and wide angle regions, we propose a joint atomic-to-nanometre scale modelling to investigate the amorphous-crystalline interplay within the nanoplates. Estimates are extracted for the thickness of the entire nanoplates and the crystalline core, together with the quantification of the amorphous fraction and apatite lattice strain. Based on the thickness matching, the location of the amorphous material mostly along the edges of the nanoplates is inferred, with a vanishing or very thin layer in the thickness direction, suggesting a core-crown-like arrangement, with possible implications on the mineral surface reactivity.
Topics: Apatites; Biomimetics; Scattering, Small Angle; X-Ray Diffraction; X-Rays
PubMed: 32438109
DOI: 10.1016/j.actbio.2020.04.026