Enamel repair

In addition to promoting periodontal tissue regeneration, a study published in 2014 has shown that EMD promoted in vitro biomimetic mineralization and facilitated enamel prism-like tissue formation on demineralized human enamel. Thus, using EMD in biomimetic mineralization may serve as a biomaterial for enamel repair (Cao et al., 2014). So far, several brands based on EMD have been marketed the first to be commercially available of those is Emdogain. 

Fig. 27 Cross-section SEM image (a) and the schematic models (b) of the enamel repair by using nanoparticles and glutamic acid. Reprinted with permission from Wiley-VCH. ...

Assists in growth and repair of body tissues and maintenance of myelin sheaths protecting nerve cells Necessary for formation of tooth enamel and elastin and collagen... 

Flard tissue engineering can include structures such as bone, and several examples of bone tissue engineering are presented in the sections above, other hard tissues that can potentially be repaired by self-assembling peptides include human dental enamel. Kirkhan and colleagues (2007) used self-assembling anionic peptides named Pn-4 to promote... 

So what might we expect in the future Ideally we should try and make tooth enamel impervious to stains. One product that might soon become available is a chewing gum which contains both calcium and phosphate to help teeth to repair cavities by boosting the natural level of these components in our saliva, part of whose job is to repair teeth -see box. However, the best agent for strengthening teeth is still fluoride. 

The average mouth excretes half a litre (500 ml) of saliva a day. This does not just lubricate the mouth and aid digestion, it contains substances that benefit the teeth, among which are calcium ions (120 mg per litre of saliva) and phosphate (14,000 mg per litre of saliva). The PH of saliva is effectively neutral, being 6.8, and this is ideal for the tooth enamel to reabsorb calcium and phosphate to repair itself. If the pH falls below 5.5, then the reverse happens and there is some loss of these components from the teeth. 

Mature enamel is a cell-free tissue while cementum though minerahzed is avascular, similar to some bone tissues, and may have developed to serve the local needs, not a primitive, but a derived and modulated tissue system (Poole, 1967). The bulk of the mineralized tooth is dentine, also a vital tissue that contains passageways known as tubules that are intermineralized with apatite. The tubules reach from the pulp cavity with its supply of nerves and blood vessels that enter at the base of the root(s) and extend to the enamel. Dentine has the possibility to repair itself. 

Lenz H, Muhlemann HR Repair of etched enamel exposed to the oral environment. Helv Odontol Acta 1963 7 47-49. 

In the realm of dentistry, restoration and protection of tooth enamel are of great importance in operative and conservative dentistry. Yamamoto et al. (2013) used PLD to create a freestanding flexible double-layered sheet composed of a 4 pm thin hydroxyapatite (HAp) layer coated with a 0.5 pm thin TCP layer. The adhesive strength between the HAp/TCP sheet and enamel was 5.7 MPa, decidedly higher than that between the monolayered HAp sheet and enamel (1.9 MPa). Electron microscopical observation revealed that the HAp/TCP sheet was largely fused with the enamel. Therefore, the double-layered HAp/TCP sheet can be used as a material to promote the repair of tooth eruption and to maintain healthy dentine. 

J Biomed Mater Res Appl Biomater 43 77-81 Johanssen E (1964) Microstracture of enamel and dentin. J Dent Res 43 1007-1009 John A, Hong L, Ikada Y, Tabata Y (2001) A trial to prepare biodegradable collagen-hydroxylapatite composites for bone repair. J Biomater Sci Polym Ed 12 689-705 Jonasova L, Muller FA, Helebrant A, Stmad J, Greil P (2002) Hydroxylapatite formation on alkali-treated titanium with different content of Na+ in the surface layer. Biomaterials 24 (in press)... 

Early non-cavitated carious lesions only may be repaired by remineraUzation processes. However partly because of the uncertainty in outcome, and partly because results are more reliable, the method of choice for the repair of a tooth damaged by caries is surgical removal of the carious region, followed by repair with some sort of synthetic material. The act of cutting out damaged tooth material (enamel and dentine) is known to compromise the mechanical properties of the tooth [43], as shown by the results in Table 1.1. In this study, a set of 10 non-carious teeth was used per experimental set. They were mounted in dental stone and tested in compression, with the load at failure in kilograms recorded. 

Dental traumatic injury often results in fracture of the affected tooth, an injury that necessitates substantial repair. This fracture can vary in severity, from involving the enamel only, through involving both enamel and dentine, to involving both tissues and also exposure of the pulp. Trauma can also affect the root of the tooth, which can themselves be fractured as a result of the incident [44], Comphcations involving the root can often follow traumatic events, and may require endodontic treatment prior to repair of the fractured tooth crown. Certain patients may damage an already traumatized tooth, and this can inhibit the healing process in the tooth and lead to a variety of complications [61],... 

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