an increasing trendp > 0.05
An increasing trend has been observed for both variables (R 2 = 0.9822 for total papers and R 2 = 0.8862 for total dental papers) with no significant differences (χ 2 (6) = 0.051 p > 0.05), although the rise in numbers of papers on dental issues has been delayed, starting from the 1990s.