Quantification of the lamina dura and dentin density in children

This study used 150 periapical radiographs of primary mandibular molars along with an aluminum stepwedge consisting of 5 steps from 2 to 10mm which were exposed and developed under standard conditions. A Mustek (Taiwan, R.O.C.) flatbed scanner with transparency adapter was used to digitize the radiographs. A 600 dpi, 10 bit gray level scanning transparency scanning mode were used. The thickness of the lamina dura was measured with the electronic ruler whereas density of dentin was calculated using the density function of a software program (Image Tool 2.0). Dentin density of the bifuraction area was calculated as 7.42 +/- 37 mm=A1 in primary second molars and 11.02 +/- 1.37mm = A1 for permanent first molar teeth. Differences in the thickness of the lamina dura in primary posterior teeth ranged from 0.23 +/- 0.01mm to 0.42 +/- 0.01mm.