[Changes in secretion and composition of saliva with aging]

Area of Science:

• Gerontology
• Oral Biology
• Biochemistry

Background:

• Oral dryness affects approximately 30% of the elderly population.
• Age-related decline in salivary secretion is a common assumption.
• Understanding salivary changes in healthy aging is crucial for oral health.

Purpose of the Study:

• To investigate age-related changes in salivary flow rate and composition in healthy elderly individuals.
• To determine if salivary secretion truly decreases with age in the absence of confounding factors.

Main Methods:

• Analysis of salivary flow rates (parotid and minor glands) under varying stimulation conditions.
• Assessment of the organic composition of saliva, including specific proteins and mucins.
• Inclusion criteria focused on healthy elderly individuals without medication or salivary gland disorders.

Main Results:

• No significant age-related decrease in overall salivary flow rate was observed in healthy elderly individuals.
• A slight reduction in secretion from seromucous glands was noted under minimal or extended stimulation.
• No age-related changes were found in parotid saliva secretion.
• Decreased concentrations of kallikrein, sIgA, and mucins were observed in elderly saliva.

Conclusions:

• Salivary flow rate is largely maintained in healthy aging, challenging the assumption of age-related reduction.
• Changes in the organic composition of saliva, particularly reduced immune factors and mucins, may impact oral cavity defense mechanisms in the elderly.
• Further research is needed to understand the implications of these compositional changes on oral health in older adults.