Discoloration of Teeth
Linda Greenwall in Tooth Whitening Techniques, 2017
Teeth are polychromatic (Louka 1989). The color varies among the gingival, incisal, and cervical areas according to the thickness, reflectance of different colors, and translucency in enamel and dentin (see Figure 1.2). The color of healthy teeth is primarily determined by the dentin and is modified by the following: The color of the enamel covering the crown.The translucency of the enamel, which varies with different degrees of calcification.The thickness of the enamel, which is greater at the occlusal or incisal edge of the tooth and thinner at the cervical third (Dayan et al. 1983).The intensity, thickness, structure of the dentin.Presence of secondary or tertiary dentin trauma.Existing restorations.
Quantum Dots as Biointeractive and Non-Agglomerated Nanoscale Fillers for Dental Resins
Mary Anne S. Melo in Designing Bioactive Polymeric Materials for Restorative Dentistry, 2020
The replacement of restorations involves patients in a restorative spiral circle (Sheiham 2002), with a gradual increase of cavities size, leading to the loss of dental structures over time (Schwendicke et al. 2016; Deligeorgi et al. 2001). A reliable dental-resin interface is not simple to be created, mostly when the restoration involves the hybridization of dentin. Dentin is a more heterogeneous tissue and has more water content in comparison to enamel (Nakabayashi 1998). In this context, the long-lasting performance of composite resins restorations is affected by the bonding performance and by the maintenance of dentin-adhesive interface stability over time. Unfortunately, this site is the most susceptible area of failure (Spencer et al. 2010).
Oral and craniofacial disorders
Angus Clarke, Alex Murray, Julian Sampson in Harper's Practical Genetic Counselling, 2019
The most common of the defects of dentine is dentinogenesis imperfecta. This may occur in isolation, inherited in an autosomal dominant pattern, or in the various forms of osteogenesis imperfecta. The teeth are opalescent with an amber or grey colour. The teeth may be subject to attrition and chipping, most probably due to fractures within the dentine. Dentinogenesis imperfecta occurring alone is determined by the DSPP gene on 4q. When associated with osteogenesis imperfecta, there may be more variation in the severity of involvement, with some teeth being clinically normal, although radiographically and histologically they may show abnormalities.
Dental stem cells in tooth regeneration and repair in the future
Published in Expert Opinion on Biological Therapy, 2018
Christian Morsczeck, Torsten E. Reichert
The dental pulp is a connective tissue of the tooth, which is connected with the mineralized tissue dentin. Dentin is a porous bone-like matrix that surrounds the dental pulp. Both tissues represent the dentin–pulp complex. The dentinogenesis is initiated by odontoblasts, the mineralizing cells of the dental pulp. Odontoblasts are able to regenerate minor hard tissue damage caused by tooth decay. Undifferentiated cells of the dental pulp are the origin of odontoblasts and these dental pulp stem cells (DPSCs) were already isolated from postnatal teeth [2] as well as from the very rare natal teeth [21]. DPSCs are plastic adherent fibroblast-like cells. They form clonogenic colonies on cell culture dishes that define their ability to self-renew. The self-renewal ability of human DPSCs was also demonstrated by the isolation and cultivation of human stem cells from stem cell transplants previously transplanted into immunocompromised mice [22]. DPSCs are peri-vascular located and express a number mesenchymal stem cell (MSC) markers such as CD105, CD146, CD44, and Stro-1 [8]. DPSC-like cells were also isolated from human deciduous teeth; these cells are known as stem cells of human exfoliated deciduous teeth (SHED) [23]. SHED can be cultivated either as plastic adherent cells or as neurosphere-like cell clusters.
Cell homing strategy as a promising approach to the vitality of pulp-dentin complexes in endodontic therapy: focus on potential biomaterials
Published in Expert Opinion on Biological Therapy, 2022
Elaheh Dalir Abdolahinia, Zahra Safari, Sayed Soroush Sadat Kachouei, Ramin Zabeti Jahromi, Nastaran Atashkar, Amirreza Karbalaeihasanesfahani, Mahdieh Alipour, Nastaran Hashemzadeh, Simin Sharifi, Solmaz Maleki Dizaj
Dentin is an inactive mineralized connective tissue that remains unaltered if the permanent tooth is not injured. One alternative is the recently created biomaterial demineralized dentin matrix (DDM). It is composed of demineralized autogenous tooth dentin, which has been used as a recombinant human bone morphogenetic protein (rhBMP-2) vector and osteoinductive bone substrate to allow continuous release and promote osteogenic differentiation [99]. DDM applies as direct pulp capping to regenerate the damaged part of dentin in permanent teeth [100]. This phenomenon is attributed to dentin tissue’s BMP activity [101,102]. The dentin matrix is a source of non-collagenous proteins that are released during tissue demineralization, which induces a regenerative role for the dentin section. In the cell homing strategy for dentin reconstruction, the treatment of teeth damaged by detergents such as ethylene diamine tetraacetic acid (EDTA) [103,104], restorative such as mineral trioxide (MTA) [105], calcium hydroxide [106], dental adhesives [107], and natural or synthetic scaffolds are closely related to migratory cells and dentin tissue. These previously stated extrinsic stimuli such as BMPs, GFs, and tissue proteases [108–110] might generate angiogenic, metabolic, and chemotactic cytokines in teeth that stimulate restorative processes [109,111,112]. These molecules are effective in regenerating dentin tissue. In some studies, ultrasonic [113] or epigenetic modifiers (histone deacetylase inhibitors) [114] are used to improve better release bioactive groups.
X-ray microtomography assessment of Carisolv and Papacarie effect on dentin mineral density and amount of removed tissue
Published in Acta Odontologica Scandinavica, 2018
Jehan AlHumaid, Fahad Al-Harbi, Maha El Tantawi, Abeer Elembaby
Rotary and sharp-edged hand instruments are used to excavate caries and this is associated with problems such as pulp overheating, need for local anaesthesia and discomfort leading to increased patient anxiety. To overcome these drawbacks, minimally invasive alternative methods were developed including chemomechanical caries removal [1–3]. This method depends on softening carious tissue by chemically altering it so that it can be mechanically removed using hand instruments [2]. The agents used in this procedure are either sodium hypochlorite-based or enzyme-based [2]. Agents of the type I degrade collagen in carious dentin to facilitate its removal. Initially, 5% sodium hypochlorite was used but because it lacked selectivity to remove only carious dentin and was unstable, amino acids were added to later formulation. The only commercially available hypochlorite-based chemomechanical caries removal agent [2] is Carisolv (MediTeam, Goteborg, Sweden), launched in 1998. It degrades the organic component of infected dentin so that it can be removed. The only enzyme-based commercially available chemomechanical caries removal agent [2] is Papacarie (Fórmula and Açäo, Sao Paulo, Brazil), introduced in 2003. It is extracted from plants and contains papain; an enzyme similar to human pepsin with proteolytic action [4].