Comparative study of tissue structure and composition of human and dog supragingival tartar.

Objective: Only a few anatomical studies have compared tartar between humans and animals. This study aimed to compare the structure and chemical composition of human and dog supragingival tartars using histological and analytical methods.

Design: Supragingival tartar samples were obtained from humans and indoor dogs with advanced periodontal disease.

Evaluation of Enamel Acid Resistance and Whitening Effect of the CAP System.

This study aimed to compare the effectiveness of a novel professional tooth-strengthening system and a conventional caries-prevention method that involved the use of high fluoride concentrations, to determine whether the system has a whitening effect. Bovine tooth-enamel samples were treated with fluoride gel (conventional APF method) or a mixture of citric acid gel, calcium phosphate (α-TCP), and fluoride gel, referred to as the CAP system; these treatments were performed to generate an acid-resistant layer on the enamel surface. For the evaluation of the acid resistance, a cyclic experiment, involving a 1-h remineralization and a 24-h acid treatment, was conducted thrice after the treatments.

Characterization of Living Dental Pulp Cells in Direct Contact with Mineral Trioxide Aggregate.

Mineral trioxide aggregate (MTA) was introduced as a material for dental endodontic regenerative therapy. Here, we show the dynamics of living dental pulp cells in direct contact with an MTA disk. A red fluorescence protein (DsRed) was introduced into immortalized porcine dental pulp cells (PPU7) and cloned.

Overactivation of the NF-κB pathway impairs molar enamel formation.

Objective: Hypohidrotic ectodermal dysplasia (HED) is a hereditary disorder characterized by abnormal structures and functions of the ectoderm-derived organs, including teeth. HED patients exhibit a variety of dental symptoms, such as hypodontia. Although disruption of the EDA/EDAR/EDARADD/NF-κB pathway is known to be responsible for HED, it remains unclear whether this pathway is involved in the process of enamel formation.

A new method for estimating time since death by analysis of substances deposited on the surface of dental enamel in a body immersed in seawater.

The present investigation was performed with the objective of developing a method to estimate how long a corpse had been immersed in water after death (the time since death). Accurate determination of the time elapsed since death may lead to identification of the place of drowning, and therefore, serves not only as a piece of information useful for determination of the cause of death but also leads to prompt identification of the body. The results showed that diatoms attached to the surface of dental enamel increased with prolongation of immersion time in water.

FAM83H and casein kinase I regulate the organization of the keratin cytoskeleton and formation of desmosomes.

FAM83H is essential for the formation of dental enamel because a mutation in the FAM83H gene causes amelogenesis imperfecta (AI). We previously reported that the overexpression of FAM83H often occurs and disorganizes the keratin cytoskeleton in colorectal cancer cells. We herein show that FAM83H regulates the organization of the keratin cytoskeleton and maintains the formation of desmosomes in ameloblastoma cells.

Ultrastructural Analyses of Alveolar Bone in a Patient With Osteomyelitis Secondary to Osteopetrosis: A Review of the Literature.

Osteopetrosis is a generic term for generalized sclerotic conditions caused by rare genetic disorders. Decreased osteoclastic activities disturb bone remodeling, resulting in greater mineral density and greater compressive strength; therefore, bone fracture is a major physical symptom of osteopetrosis. Osteomyelitis of the maxilla or mandible is a common and well-documented complication of osteopetrosis.

Identification, characterization, and expression of dentin matrix protein 1 gene in Xenopus laevis.

Dentin matrix protein 1 (DMP1) is an acidic extracellular matrix protein expressed mainly in bone and dentin, and is a member of the small integrin-binding ligand N-linked glycoprotein (SIBLING) family. The DMP1 gene, however, appears to evolve rapidly in comparison with other SIBLING genes, even though such functionally important molecules usually evolve more slowly than less important ones. The purpose of this study was to identify and characterize an ortholog of the DMP1 gene in an amphibian (Xenopus laevis; X.

Immunolocalization of TAK1, TAB1, and p38 in the developing rat molar.

In tooth development, transforming growth factor beta (TGF-β) and bone morphogenetic protein (BMP) are involved in cell differentiation and matrix protein production. TGF-β and BMP have two signaling pathways: the Smad pathway and the non-Smad pathway. However, only a few studies have focused on the non-Smad pathway in tooth development.

Surface observation of thin hydroxyapatite-coated implants at 80 months after insertion.

We observed surfaces and cross sections of thin hydroxyapatite (HA)-coated implants produced by the thermal decomposition method in a patient attending our clinic who underwent implant removal at 80 months due to fracture of the implants. On the implant surfaces of the removed sample, most of the HA had dissolved, and extensive osseointegration was observed where Ti had closely bonded to bone. This indicated that the HA coated on the implant surfaces had disappeared and osseointegration had been established where Ti directly bonded to the bone.

Transforming growth factor β inducible apoptotic cascade in epithelial cells during rat molar tooth eruptions.

In tooth eruptions, the presence of apoptotic epithelial cells at the eruption site has been reported, but the factors that induce apoptosis in these cells remain to be elucidated, as do the induction pathways. In this study, we focused our attention on transforming growth factor beta (TGF-beta), which is known to induce apoptosis during embryonic development. Oral epithelium and dental lamina of maxillary first molars in 8- and 15-day-old rats were used to investigate the induction pathway of apoptosis by performing the immunohistochemical tests outlined below and assessing the characteristics of cells that undergo apoptosis by transmission electron microscopy in rats 8 and 15 days after birth.

Ultrastructural study of tissues surrounding replanted teeth and dental implants.

Objectives: The aim of this study was to describe the ultrastructure of the dentogingival border at replanted teeth and implants.

Material And Methods: Wistar rats (8 weeks old) were divided into groups for replantation and implantation experiments. In the former, the upper right first molars were extracted and then immediately replanted.

Detailed consideration of physicochemical properties of CO3apatites as biomaterials in relation to carbonate content using ICP, X-ray diffraction, FT-IR, SEM, and HR-TEM.

CO3apatites with different carbonate contents were synthesized at 60 +/- 1 degrees C and pH 7.4 +/- 0.2 under different carbonate concentrations (0-0.

SEM observation of collagen fibrils secreted from the body surface of osteoblasts on a CO3apatite-collagen sponge.

The secretion of collagen by osteoblasts was observed by scanning electron microscopy (SEM). Osteoblast-like cells were cultured on a CO3apatite-collagen sponge reinforced with a porous HAp frame. After three days' incubation, a number of newly created matrix fibrils, forming a network structure, were observed at the cell surface.

Fluoride and apatite formation in vivo and in vitro.

In recent years, the biomineralization process has attracted much interest from academics and industries for potential technological application. The rule in biomineralization is to have a variety of interfaces and surfaces which can act as nucleators. The ultimate step in any biomineralization process, i.

High-resolution electron microscopy of enamel-crystal demineralization and remineralization in carious lesions.

Although dental caries destroys dental hard tissues, both demineralization as a destructive process and remineralization as a restorative process take place in carious lesions. These conflicting processes occur constantly either simultaneously or alternately. In crystallographic terms, demineralization is crystal dissolution, and remineralization is restoration of partially dissolved crystals, new crystal formation and growth of surviving crystals.

Remineralization effects of xylitol on demineralized enamel.

We morphologically determined the effects of xylitol on the remineralization of artificially demineralized enamel. The samples were demineralized and then immersed in a remineralizing solution with or without 20% xylitol at 37 degrees C for 2 weeks. Samples were observed using contact microradiography, a multipurpose image processor (MIP) and a high-resolution electron microscope (HRTEM).

Adhesion of 4-META/MMA-TBB resin to heated dentin: effects of pre-treatments with FeCl3 and/or HEMA.

The purpose of this study was to compare the tensile bond strengths (TBSs) and failure mode of 4-META/MMA-TBB resin to 60 degrees C-heated and unheated bovine dentin, especially to investigate the influence of ferric chloride contained in citric acid pre-conditioning. In addition, the effect of HEMA priming for heated dentin was also evaluated. The TBSs to heated dentin were significantly lower than those to unheated dentin.