|Author||Year and country||Sample size (n) and study population||Methodology||Formula||Error estimatea|
|Drusini et al. (Drusini et al. 1991)||1991 Italy||n= 152 single-rooted teeth were collected.||
Root dentin transparency was measured under bright light. Measurement was done from the apex of the tooth to the most coronal extent of the transparency.|
Measurements were done both by Vernier caliper and densitometric IBAS system.
The errors range from ±5 to more than ±20 years. The highest percentages of success|
within ±5 years were obtained for premolars.
|Zander et al. (Zander and Hurzeler 1958)||1958 New York||n=233 single-rooted teeth were collected from age range of 11 to 76 years.||Teeth were decalcified and sectioned horizontally from apex to cementoenamel junction.||Thickness of cementum= [a x 0.71] ÷ [b x 0.032]||
Average cemental thickness below 20 years= 0.076 mm|
Average cemental thickness from 51 to 76 years= 0.215 mm.
Thickness of cementum tripled over years.
|Pinchi et al. (Pinchi et al. 2007)||2007 Italy||n=127 teeth from age group of 16–90 years.||
Teeth were decalcified and sections were obtained.|
Measurements obtained were 1/3rd of root length on lingual side, 1/3rd f root length on vestibular side, thickness at apex.
|y= [6 x 10-7x3] - [0.0009x2] + [0.3743x] + 12.14||Age estimated was 58.6 years ± 1.49 years with 95% reliability.|
|Stott et al. (Stott et al. 1982)||1982 Texas||n=10 teeth were prepared for processing and they were obtained from 3 dissection cadavers.||
Teeth were sectioned using low speed saw and diamond blade and sections of 100–150μ were obtained.|
Sections were stained with Alizarin red stain and cemental annulations were studied.
Cadaver 1: known age=57 years.|
Estimated age=58±1 years.
Known age=67 years.
Estimate age = 63–70 years.
Known age=76 years.
Estimated age= 73–78 years.
|Wittwer-Backofen (Wittwer-Backofen et al. 2004)||1990||-||
Teeth were sectioned and sections were observed under transmitting light microscopy.|
Representative images were captured and processed with image analysis software.
|-||A confidence interval of 2.5 years was obtained but can exceed these error ranges if teeth are post-mortally affected.|
|Solheim et al. (Solheim 1990)||1990 Norway||n=1000 teeth, 100 of each type excluding molars in Caucasian population.||Half-sectioned teeth was stained with carbol fuschin and cementum was studied with stereomicroscope.||-||Strongest correlation was found in range, i.e., r=0.54 for maxillary incisors and r=0.75 for mandibular second premolars.|
|Kosa et al. (Kosa et al. 1990)||1990 Hungary||Single-rooted teeth of 25 individuals were selected.||
Weight concentrations of calcium and phosphorus and Ca/P weight ratio was calculated with the help of electron probe microanalysis in dentin.|
TESLA BS-300 SEM (scanning electron microscope) was used coupled with X-ray detector and X-ray analyzer.
Y= 37.17x + 139. 37|
X is the age
Y is the Ca/P weight ratio
|Weight concentration of phosphorus was having closer correlation with age (r=0.9712).|