“…The sinus invades the frontal bone by about 5 years of age and slowly grows to reach an adult size in late adolescence (Miller & Amedee, 1998). Whilst it is widely accepted that the development of the frontal sinus is complete by about 20 years of age and remains stable until further enlargement of the chambers can occur from bone resorption during the advanced ages (Yoshino et al, 1987;Quatrehomme et al, 1996;Kirk et al, 2002); Tatlisumak et al, reported that, the highest values of measurements of frontal sinus were at the 31-40 age group in both sexes and there were a tendency to decrease with aging (Tatlisumak et al, 2008). Also, McLaughlin et al, suggested that the frontal sinus continued to expand until the age of 40 years because of mechanical stresses of mastication and growth hormone levels (McLaughlin et al, 2001).…”