Quantitative age-related differences in human sublingual gland

OBJECTIVE: To quantify morphological age- and gender-related differences in human sublingual glands (SLG). DESIGN: Ninety right human SLG from necropsies were distributed by gender and age groups. Individuals with ages ranging from 7 months to 92 years were divided into Groups I (0-30 years), II (31-60 years) and III (61-92 years). The glandular volume of each SLG was calculated. The morphometric quantifications of the volume density and total volume of acini, ducts, stroma, adipose tissue and septa were realized under light microscopy using a Zeiss II integration grid with 100 points symmetrically distributed. RESULTS: The glandular volume decreased, on average, 33.78% across the groups. The volume density (V(V)) of acini reduced 60.54% and of septa 34.82%, being replaced partly by an increase of 58.82%, 551.22% and 2,783.33% in the volume density of ducts, stroma and adipose tissue, respectively. In absolute terms, with aging, the total volume (V(T)) of the acini decreased by 54.04% and by 34.84% in the septa. In contrast, the total volume of ducts, stroma and adipose tissue showed increases of 62.53%, 363.25% and 2,308.64%, respectively. Both the V(V) and the V(T) of acini, ducts, stroma and adipose tissue and the V(V) of septa were statistically different with age. No significant difference was observed between genders. CONCLUSION: The decrease of parenchyma accompanied by an increase of stroma observed here in SLG is a common feature of aging in human salivary glands.