BIOCHEMISTRY OF SALIVA AND DENTAL CARIES

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Abstract

Caries is a unique multifactorial infectious disease. Our understanding of etiological factors, the progress of the disease, and the effectiveness of prophylactic procedures have led us to believe that we understand the disease. However, we still have too few answers to many questions: “Why can we not predict who will get the disease?” “Why do we not become immunized?” “How much saliva is enough?” or “Which salivary components are protective?” and “Which salivary components predispose for caries?” It is generallaccepted, however, that saliva secretion and salivary components secreted in saliva are important for dental health. The final result, “caries to be or not to be”, is a complex phenomenon involving internal defense factors, such as saliva, tooth surface morphology, general health, and nutritional and hormonal status, and a number of external factors-for example, diet, the microbial flora colonizing the teeth, oral hygiene, and fluoride availability. In this seminar, our aim is to focus on the Biochemistry of saliva and salivary constituents on cariogenic bacteria and the subsequent development of dental caries.
CHAPTER ONE

INTRODUCTION

Saliva and oral health Saliva is a mucoserous fluid secreted by three pairs of major salivary glands (parotid, submandibular and mandibular), as well as by minor glands on the lower lip, tongue, palate and cheeks. Saliva production begins within specialized acinary cells contained inside the glands, after which salivary secretions are transported and further modified along the salivary ducts. Whole saliva is a complex mixture composed of secretions from the salivary glands, gingival crevicular fluid, food debris, and components derived from oral microflora as well as from exfoliating oral mucosal cells and host immune cells. Saliva is essential for oral health.

This can be inferred by observing the consequences of insufficient salivary production. Salivary secretion impairment may be caused by Sjögren’s syndrome (an autoimmune condition), radiation therapy, but it most commonly appears as a side-effect of xerostomic medications. Regardless of etiology, the effect is highly damaging: oral soreness and discomfort, loss of taste, difficulty in swallowing, increased caries, candidiasis. One of the primary roles of saliva is to minimize and repair acid-induced demineralization of the tooth enamel. The hydroxyapatite component of dental enamel begins to demineralize.