A T-score of 2.9 is considered normal. A T-score measures a person's bone density to others of the same sex and race, according to WebMD.
A higher T-score corresponds with a higher bone density, while a lower score corresponds with lower bone density. A T-score of -1 and above is considered normal, while a T-score ranging between -1 and -2.5 signifies osteopenia, or subpar bone density that often leads to osteoporosis. A T-score of -2.5 and below means the subject probably has osteoporosis, according to Mayo Clinic. In addition to T-score, medical professionals also measure bone density using Z-score, which uses standard deviations above or below the averages based on sex, racial ethnicity, age and weight.