Diagnostic Biomarkers for Oral and Periodontal Diseases

Microbial factors for the diagnosis of periodontal diseases

Of the more than 600 bacterial species that have been identified from subgingival plaque, only a small number have been suggested to play a causal role in the pathogenesis of destructive periodontal diseases in the susceptible host [16]. Furthermore, technologic advances in methodologies such as analysis of 16S ribosomal RNA bacterial genes indicate that as many as several hundred additional species of not-yet-identified bacteria may exist [19]. The presence of bacteria adjacent to the gingival

Host response and inflammatory mediators as potential biomarkers

Periodontal inflammation occurs in the gingival tissue in response to plaque bacteria biofilms [3], [41]. Gingivitis is characterized by an initial increase in blood flow, enhanced vascular permeability, and the influx of cells (neutrophils and monocyte-macrophages) from the peripheral blood to the gingival crevice [42]. Subsequently, T cells and B cells appear at the infection site. After they appear at the lesion, these cells produce a myriad of cytokines such as IL-1β, IL-6, TNF-α, and

Bone-specific markers of tissue destruction for periodontal diagnosis

Of the 50 or more different components in GCF and saliva evaluated to date for periodontal diagnosis, most lack specificity to alveolar bone destruction and essentially constitute soft tissue inflammatory events [92]. When examining the destruction of alveolar bone that is preceded by a microbial infection and inflammatory response, the measurement of connective tissue–derived molecules may lead to a more accurate assessment of tissue breakdown due to the tremendous variability of the host

Pyridinoline cross-linked carboxyterminal telopeptide of type I collagen

Type I collagen composes 90% of the organic matrix of bone and is the most abundant collagen in osseous tissue [94]. Collagen degradation products have emerged as valuable markers of bone turnover in a multitude of bone resorptive and metabolic diseases [95]. Pyridinoline cross-links represent a class of collagen degradative molecules that include pyridinoline, deoxypyridinoline, N-telopeptides, and C-telopeptides [96]. Pyridinoline and deoxypyridinoline are mature intermolecular cross-links of

Osteocalcin

Osteocalcin is a calcium-binding protein of bone and is the most abundant noncollagenous protein in mineralized tissues [112]. Osteocalcin is synthesized predominantly by osteoblasts [113] and has an important role in bone formation and turnover [114], [115]. Osteocalcin exhibits chemoattractive activity for osteoclast progenitor cells and monocytes [116], [117], [118], and its synthesis in vitro is stimulated by 1,25-dihydroxyvitamin D₃. It has also been shown to promote bone resorption, and

Role of oral fluid biomarkers in periodontal diagnosis

A biomarker or biologic marker, according to the most recent definition [128], is a substance that is objectively measured and evaluated as an indicator of normal biologic processes, pathogenic processes, or pharmacologic responses to a therapeutic intervention. Because saliva and GCF are fluids easily collected and contain locally and systemically derived markers of periodontal disease, they may offer the basis for a patient-specific biomarker assessment for periodontitis and other systemic

Future directions

There is a plethora of possibilities for the future use of oral fluids in biotechnology and health care applications, especially in the field of diagnostics. A tremendous amount of research activity is currently under way to explore the role of oral fluids as a possible medium in a variety of applications.

Recent advances in HIV diagnosis have been made using oral fluids. A commercially available kit (OraSure, OraSure Technologies, Bethlehem, Pennsylvania) has an oral specimen collection device

Summary

Researchers in the biotechnology and medical realm are currently investigating the use of oral fluids for the diagnosis of oral and systemic diseases and for drug development. In the pharmaceutical industry, the use of biomarkers is avidly being developed for use in tailored dosing and drug metabolism studies. Professionals in seemingly unrelated arenas such as the insurance industry, the Environment Protection Agency, and Homeland Security are interested in the possible use of oral fluids to