Frontiers of Oral Biology

Using global gene expression analysis, the effects of biomaterials and nanomaterials can be analyzed at the genetic level. Even though information obtained from global gene expression analysis can be useful for the evaluation and design of biomaterials and nanomaterials, its use for these purposes is not widespread. This is due to the difficulties involved in data analysis. Because the expression data of about 20,000 genes can be obtained at once with global gene expression analysis, the data must be analyzed using bioinformatics...

The use of titanium dental implants has consistently changed the way of rehabilitating patients in modern dentistry and can count on high long-term survival and success rates. With respect to its introduction in the late 1960s, clinical indications for implant therapy have been significantly extended and optimal results have been achieved, even in clinical conditions formerly considered as unfavourable. Such evolution owes a lot to the significant progress made in the field of titanium surfaces. The topographical and chemical modification of traditional titanium surfaces has led to a real epochal shift in implant dentistry...

During the last decade, there has been a major increase in the interest of nanostructured materials in advanced technologies for biomedical and dental clinical applications. Nanostructured materials are associated with a variety of applications within the dental and biomedical field, for example nanoparticles in drug delivery systems and nanostructured scaffolds in tissue engineering. More importantly, nanotechnology has also been linked with the modification of surface properties of synthetic implants in an attempt to improve their bioactivity, reliability and protection from the release of harmful or unnecessary metal ions...

This chapter provides a tool for the integration of new concepts and biomaterials related with the resin-dentine interface. The principles of dentine demineralisation and remineralisation that shape modern restorative dentistry practices, as well as considerations for the selection of new materials for different restorative approaches, are emphasised. Re-incorporation of mineral into the demineralised dentine matrix is important since the mineral precipitated may work as a constant site for further nucleation, and the remineralised subsurface of the tissue may be more resistant to subsequent acid attack...

Bioactive ceramics are known to exhibit specific biological affinities and are able to show direct integration with surrounding bone when implanted in bony defects. However, their inadequate mechanical properties, such as low fracture toughness and high Young's modulus in comparison to natural bone, limit their clinical application. Bone is a kind of organic-inorganic composite where apatite nanocrystals are precipitated onto collagen fibre networks. Thus, one way to address these problems is to mimic the natural composition of bone by using bioactive ceramics via material designs based on organic-inorganic composites...

For many years, bioactive glasses (BGs) have been widely considered for bone tissue engineering applications due to their ability to bond to hard as well as soft tissue (a property termed bioactivity) and for their stimulating effects on bone formation. Ionic dissolution products released during the degradation of the BG matrix induce osteogenic gene expression leading to enhanced bone regeneration. Recently, adding bioactive metallic ions (e.g. boron, copper, cobalt, silver, zinc and strontium) to silicate (or phosphate and borate) glasses has emerged as a promising route for developing novel BG formulations with specific therapeutic functionalities, including antibacterial, angiogenic and osteogenic properties...

The successful clinical application arising from advances in polymer and macromolecular sciences in different fields of medicine has opened new explorative approaches for the future design and development of the ever more sophisticated bio-/nanotechnologies that are needed to realise the full potential of modern dentistry. In this chapter, the most recent polymer therapeutic approaches for alveolar ridge augmentation, bone grafts, periodontal disease, restorative materials and scaffolds or carriers for cell-based therapies are presented highlighting the potential of either synthetic or natural polymers, such as polyesters, polyolefins, polyacrylates or chitosan for example, being tailored and engineered to yield a range of properties valuable in the design and development of dental polymer therapeutics...

Dental caries remains a challenge in the improvement of oral health. It is the most common and widespread biofilm-dependent oral disease, resulting in the destruction of tooth structure by the acidic attack from cariogenic bacteria. The tooth is a heavily mineralised tissue, and both enamel and dentine can undergo demineralisation due to trauma or dietary conditions. The adult population worldwide affected by dental caries is enormous and despite significant advances in caries prevention and tooth restoration, treatments continue to pose a substantial burden to healthcare...

Normal development of the palate depends on spatial and temporal coordination of complex cellular processes and tissue-tissue interactions. Because these processes are quite sensitive to environmental and genetic perturbation, clefts of the palate are among the most common congenital anomalies seen in live births. The clinical burden of cleft palate is significant, as conventional treatments include surgical repair combined with long-term rehabilitation. Affected children may require multiple operations and often have secondary problems such as perturbed speech development, dental occlusion, maxillary growth deficiencies and otitis media...

This chapter describes the normal development of speech and speech problems that may arise for the child born with cleft lip and/or palate. It describes current trends and the importance of multidisciplinary working in this complex field. The contribution of the speech and language therapist to the management of this population is considered.

In the 1970s, Boyne and Sands published reports on a new technique for alveolar bone grafting. They recommended that only cancellous bone be used and that the procedure be undertaken in the mixed dentition prior to canine eruption. Alveolar bone grafting prior to canine eruption soon became a routine part of the protocol for 90% of European and North American cleft teams. Several uncertainties remain however, such as the specifics of the surgical and orthodontic procedures, type of bone and donor site, and the best way to manage the space in the dental arch...

The orthodontic treatment of patients with all types of cleft lip and palate, a resume of facial growth and discussion on dental and occlusal development is presented. A fully integrated cleft team provides life-long interdisciplinary holistic treatment for patients born with an orofacial cleft. To understand the team approach to cleft care, this article should be read in close conjunction with those on speech therapy, surgery and alveolar bone grafting to determine the synergy required between these and other clinical specialties...

Surgical cleft repair aims to restore function of the oro-nasal sphincter and oro-nasal soft tissues and re-establish the complex relationship between perioral and perinasal muscle rings without compromising subsequent mid-facial growth and development. Here we review the surgical anatomy of this region, optimal timing for surgical repair and current thinking on the use of surgical adjuncts. In addition, an overview of current surgical techniques available for the repair of cleft lip, cleft palate and velopharyngeal insufficiency is presented...

In the management of children born with orofacial clefting there is a danger that the information on genetic and environmental influences together with data emerging from randomized controlled trials are divorced from the current reality of clinical care. It is important that treatment outcomes are constantly reviewed as new evidence unfolds but for many children born with a cleft, basic care will be more rapidly improved through examination of quality of outcomes than the higher level scientific exploration of gene-environment interactions and clinical trials...

Wnt signaling regulates a variety of cell behaviors and represents a major pathway in development and disease. Mutations in Wnt genes and their downstream targets have been implicated in human craniofacial abnormalities, including the most prevalent birth defect, cleft lip with or without palate. Formation of the upper lip and palate is a complicated process and is composed of a series of highly coordinated steps during tissue morphogenesis, which are rigorously controlled by genetic networks. While genetic controls of lip/palate development have been extensively studied, the roles of Wnt signaling in these processes remained poorly understood...

The fibroblast growth factor (FGF) signalling pathway is critically involved in several aspects of craniofacial development, including formation of the lip and the palate. FGF receptors are activated by extracellular FGF ligands in order to regulate cellular processes such as migration and morphogenesis through instruction of specific target gene expression. A key factor in the development of orofacial structures is the interaction between mesodermal- and neural crest-derived mesenchyme and ecto- and endodermal-derived epithelium...

Cleft lip with or without cleft palate (CLP) and cleft palate only (CP) are severe disruptions affecting orofacial structures. Patients with orofacial clefts require complex interdisciplinary care, which includes nursing, plastic surgery, maxillofacial surgery, otolaryngology, speech therapy, audiology, psychological and genetic counseling, orthodontics and dental treatment, among others. Overall, treatment of clefts of the lip and palate entails a significant economic burden for families and society. Therefore, prevention is the ultimate objective and this will be facilitated by a complete understanding of the etiology of this condition...

The Sonic hedgehog (Shh) gene encodes a secreted signalling molecule that plays an important role during numerous aspects of vertebrate development. In the developing palate, Shh is strongly expressed in the epithelium on the oral surface, in a series of stripes corresponding to the future rugae palatini. There is now good evidence that Shh is involved in a number of signalling interactions that take place between the epithelium and mesenchyme during normal palatogenesis. In particular, being able to induce Fgf10 in mesenchyme of the anterior palate which, via Fgfr2, is able to induce Shh in the epithelium...

Vertebrate and invertebrate model organisms are essential for deciphering biological processes. One of these, the mouse, proved to be a valuable model for understanding the etiopathogenesis of a vast array of human diseases, including congenital malformations such as orofacial clefting conditions. This small mammal's usefulness in cleft lip and palate research stems not only from the striking anatomical and molecular similarities of lip and palate development between human and mouse embryos, but also from its amenability to experimental and genetic manipulation...

Cleft lip and palate is the most common craniofacial birth defect and its etiology has been the focus of many reports in the literature. It is well accepted that both genetics and environment play a role in the condition, however we still have not been able to translate what have been learned into clinical applications. This paper provides an interpretation of the latest research findings in humans and a perspective for where the field is going. The latest effort in gene identification and the associations between isolated cleft lip and palate and the loci harboring IRF6 (1q32) and 8q24...