The bone density test is painless and quick. LIMB-BONE DENSITY AND AQUA TIC HABITS 199 TABLE 1-Mean limb-bone volume and density (in parentheses) for aquatic and terrestrial mammals studied (w = wild and z = zoo animals); volume in cm3, density in g/cm3. The study raises the question of serotonin as a bone metabolism marker seeing that the results were not consistent and the main limit of the study was that it did not analyze the possible use of antidepressants to these women. Use Our Quiz to Find Out! Figure 8). T-scores compare bone density with that of a healthy person, whereas Z-scores use the average bone density of people of the same age, sex, and size as a comparator. Bookmark https://www.niams.nih.gov/health-topics/bone-health and keep up with health topics related to bone health. For example, a 65-year old man with a T-score of -0.6 at the femoral neck would have the SAME risk of fracture as a 65-year old man with a T-score of the total hip of -1.06. SGLT2 inhibitors have not been studied in pregnant women, but based on animal data, they may cause harm to an unborn baby. From Fort Vancouver Yellow Pear to Santa Anna, these, Gardening Tips for Growing Tomatoes | Everything You Need to Know, Gardening is an incredibly rewarding activity, and tomatoes are one of the most popular crops to grow. Advances in Animal Models for Studying Bone Fracture Healing. 1. Figure 3 shows cattle and horse femora. Toll Free: 888-INFO-FDA (888-463-6332) Fax: 202-293-2356 No content on this site, regardless of date, should ever be used as a substitute for direct medical advice from your doctor or other qualified clinician. More stress on the bones. Food Products - Bulk Densities - Bulk densities of some common food products like grain, corn, barley, sugar and more. Whilst identifying complete bones seems relatively simple, fragmentary remains can be surprisingly difficult. They are lightweight yet strong and hard and . Bone mass measurement: What the numbers mean. Am J Sports Med. MeSH A bone density test is a kind of X-ray test. The BHOF notes that Z-scores can be misleading because older adults commonly have low bone density. Your bone density indicates you likely have osteoporosis. Good sources of vitamin K are green leafy vegetables and animal products such as eggs. As the scans use low doses of radiation, which could harm a developing baby, this procedure is not advisable during pregnancy. Permittivity and conductivity values of rat bones at 37oC Frequency . Federal government websites often end in .gov or .mil. Domestic . (The reference values are a little different from those above because this is for the femoral neck and not the total hip). . Once bone density is measured, there is a lack of consensus regarding when or if a repeat measurement should be done, according to Dr. Wermers. Proximal sesamoid bone (PSB) fracture is the leading cause of fatal musculoskeletal injury in Thoroughbred racehorses in Hong Kong and the US. document.getElementById( "ak_js_1" ).setAttribute( "value", ( new Date() ).getTime() ); Peterborough, Stamford, Oundle, Huntingdon, Crowland, Thorney, Whittlesey, Holme, Alconbury, Stilton, Alwalton, Chesterton, Warmington, Nassington, Water Newton, Sutton, Wansford, Ketton, Ailsworth, Castor, Marholm, Barnack, Helpston, Glinton, Market Deeping, Maxey, and the Fens, Thirsty Work: The Mineral Water Manufacturers of Peterborough, U-shaped mandible (no midline separation), Pronounced muscle markings, sagittal crest inferior, Orbits at sides, posterior to nasal aperture, V-shaped mandible (separates at midline), Incisors (maxillary) are larger than other mammals, Premolars and molars have low, rounded cusps divided by distinct grooves, Horse maxillary incisors are larger than human incisors, Carnivores have large conical canines. They may stem from one or more of the following: Aside from these conditions, certain medications can cause bone loss. In spring 2023, the information on this website will move to https://www.niams.nih.gov/health-topics/bone-health. Even if youre otherwise healthy, consulting a bone density chart and getting a baseline bone density scan can diagnose even the slightest beginnings of bone loss. The research suggests that these bones only look like they would be lighter. Unable to load your collection due to an error, Unable to load your delegates due to an error. High-impact weight-bearing exercises help build bones and . A T score of -2.5 or less, by definition puts you into the osteoporosis range. Figure 2: Cattle and horse 1st molars (lower). The white numbers are at the average values for that age. Telephone: 800-624-BONE | Fax: 202-293-2356 | Email: NIHBoneInfo@mail.nih.gov, Bone Mass Measurement: What the Numbers Mean, National Institute of Arthritis and Musculoskeletal and Skin Diseases, Spanish-Language Publications (en espaol), https://www.niams.nih.gov/health-topics/bone-health, World Health Organization definitions based on bone density levels, https://www.accessdata.fda.gov/scripts/cder/daf, National Institute of Diabetes and Digestive and Kidney Diseases, U.S. Department of Health and Human Services, Surgeon Generals Report on Bone Health and Osteoporosis, Surgeon Generals Report: What It Means to You, Informe del Cirujano General Sobre la Salud de los Heusos y Osteoporosis: Lo Que Significa Para Usted, Surgeon Generals Report: What It Means to You (). At very low T-scores, however, the bone density is the same. PMC However, these tests are not accurate for diagnosing osteoporosis and are only used to identify people who would benefit from bone density testing. https://www.niams.nih.gov/Health_Info/Bone/Osteoporosis/overview.asp. The NIH Osteoporosis and Related Bone Diseases ~ National Resource Center is supported by the National Institute of Arthritis and Musculoskeletal and Skin Diseases with contributions from: The National Institutes of Health (NIH) is a component of the U.S. Department of Health and Human Services (HHS). Dwarf Mr Snow, Fred's Tie Dye, Saucy Mary, Sweet Scarlet, Kangaroo Paw Green, Idaho Gem and Banana Toes are just a few of the varieties one gardener is growing in a 4x8 bed of "bulletproof" tomatoes. Heart failure: Could a low sodium diet sometimes do more harm than good? Clinical research has shown that participants using AlgaeCal Plus saw improved bone mineral density and bone density within just 6 months. As shown in the table below, a T-score between +1 and 1 is considered normal or healthy. Some investigators have tried, unsuccessfully, to establish a "standardized" unit of mg/cm2. There are a variety of bone density tests available, but the gold standard test for diagnosing osteoporosis is the DEXA scan (also written as DXA scan). The different machines still use their own reference data sets for the spine because the spine was not included in the NHANES study. A T-score for bone density reflects how much your bone density is higher or lower than that of a healthy, 30-year-old adult. Office of Patient Education. Bone density scores can tell a doctor whether a person has osteopenia or osteoporosis or is at risk of developing either condition. Accessed Nov. 25, 2020. As mentioned at the start of this guide it takes time gaining experience handling a variety of bones both on site and in reference collections to become proficient in identifying a wider range of species. T-Score Bone Density Chart: Actual size, fighting ability, aggression, ect, are more important. Keep reading to learn more about bone density scans, the difference between T-scores and Z-scores, and what Z-scores mean in terms of osteoporosis. Avoid taking calcium supplements for at least 24 hours before your bone density test. For this reason, the table lists density from lowest to highest and includes the . You have never made such a ridiculous claim. A;;ll animals are equal, but some animals are more equal than others (G. Orwell, Animal Farm, 1945). Clin Rheumatol. In dogs this runs through the articulation whereas in cats in runs to the side. Just as the percent change in the temperature of a room is the same whether you measured it in Fahenheit or centigrade. Also, there are no particular . Cardiovascular health: Insomnia linked to greater risk of heart attack. So, no, bears don't have denser bones than humans. Your T-score is your bone density compared with what is normally expected in a healthy young adult of your sex. Density Lab; Calculus Early Transcendentals 9th Edition by James Stewart, Daniel Clegg, Saleem Watson (z-lib.org) . The lower a person's T-score, the more severe their bone loss is, and the more at risk for fractures they are. For postmenopausal women and men age 50 years and older, the T-score is the number that is used for diagnostic classification, as follows: A T-score of -1.0 or above is normal bone density. Normal bone is strong and flexible. HONcode standard for trustworthy health information: verify here. But clinically we want to know whether the test can discriminate between those of the same age who will or won't fracture. As with cattle and horse remains, sheep and pigs are often confused due to their similar sizes. Would you like to order publications on bone disorders to be mailed to you? You would expect to see many _____ type of capillaries in red bone marrow. A. Dielectric properties of animal bone tissue . Medical experts consider DEXA scans to be the most useful, easy, and inexpensive test for helping to diagnose osteoporosis. A bone density test determines if you have osteoporosis a disorder characterized by bones that are more fragile and more likely to break. In addition to obtaining your initial DEXA scan results, repeating the scan every two to five years is recommended, depending on your risk factors. HHS Vulnerability Disclosure, Help How Viagra became a new 'tool' for young men, Ankylosing Spondylitis Pain: Fact or Fiction, Bone Health and Osteoporosis Foundation (BHOF), Dual-energy X-ray absorptiometry (DEXA) scans, https://www.radiologyinfo.org/en/info/dexa, https://www.bonehealthandosteoporosis.org/patients/diagnosis-information/bone-density-examtesting/, https://medlineplus.gov/lab-tests/bone-density-scan/, https://www.bones.nih.gov/health-info/bone/bone-health/bone-mass-measure, https://www.ncbi.nlm.nih.gov/labs/pmc/articles/PMC4919174/, https://americanbonehealth.org/bone-density/understanding-the-bone-density-t-score-and-z-score/. The more standard deviations below 0, indicated as negative numbers, the lower your BMD and the higher your risk of fracture. Bone density is the same as in others of the same age, sex, and body size. If you need more information about available resources in your language or another language, contact the NIH Osteoporosis and Related Bone Diseases ~ National Resource Center at NIHBoneInfo@mail.nih.gov. Bone density exam/testing. The dielectric coefficient of bone tissue has been demonstrated to be closely interrelated with its mineral density and elastic modulus, which implies that the health status and mechanical performance of bone can be evaluated by assessing its dielectric properties. They include: Doctors use Z-scores to diagnose osteoporosis in children, teenagers, premenopausal females, and younger males. Academic Press. If your bone density scan is normal, you don't need another one for up to 10 years as long as your risk factors for osteoporosis don't change. T-scores reflect how bone density compares with that of a typical, young, healthy person, whereas Z-scores use the bone density of those with similar characteristics for comparison. government site. Radiological Society of North America. Bone density tests are usually done on bones that are most likely to break because of osteoporosis, including: If you have your bone density test done at a hospital, it'll probably be done on a device where you lie on a padded platform while a mechanical arm passes over your body. What is the latest research on the form of cancer Jimmy Carter has? Aerssens J, Boonen S, Joly J, Dequeker J. J Endocrinol. The impact of medication on osseointegration and implant anchorage in bone determined using removal torque-A review. Contrast materials might interfere with your bone density test. DXA is used to measure the BMD of a specific location in the body skeleton. Summary Plant foods are rich in many important micronutrients that are beneficial for bone health. Bone scans require an injection beforehand and are usually used to detect fractures, cancer, infections and other abnormalities in the bone. Foods high in any of these four nutrients can help support bone density. Those using Strontium Boost in addition to AlgaeCal Plus saw, on average, triple the bone density increases of the AlgaeCal-only group. sharing sensitive information, make sure youre on a federal The most notable difference is the much higher and flatter skull vault in pigs compared to sheep. Dont forget that full-blown osteoporosis is a serious condition that can have devastating consequences on your health and quality of life. It may be done using X-rays, dual-energy X-ray absorptiometry (DEXA or DXA), or a special CT scan that uses computer software to determine bone density of the hip or spine. https://www.radiologyinfo.org/en/info.cfm?pg=dexa. 24, no. From the observation of body weight evolution and food spillage, no differences concerning food intake were inferred between groups or in relation to age. Although no bone density test is 100-percent accurate, the BMD test is an important predictor of whether a person will have a fracture in the future. Advertising revenue supports our not-for-profit mission. Examples: 85-yr-old white woman with T-score of -2.25 has Z-score of 0, 65-yr-old white man with T-score of -0.3 has Z-score of +0.3, 55-yr-old black woman with Z-score of -1 has T-score of -1.5, 55-yr-old black woman with Z-score of +1 has T-score of +0.5. Large interspecies differences were observed in all analyses. Reducing Muscle Soreness with Berries. Horse 1st metacarpals consist of a single bone. For example, DEXA of the hip has a relative risk of about 2.5 for each standard deviation for predicting hip fracture; therefore, a person with a z-score of -1 has 2.5 times the chance of a hip fracture compared to a woman with Z-score of zero (average). Note also the different profile of the mandible. . Find out what gives our bones their remarkable ability to heal breaks in a finely tuned process that involves stem cells, cartilage, and bone. As long as the reference data base has not changed, the percent change from two measurements will be equal using BMD or T-scores. Whilst this is beyond the scope of a short introduction, having the knowledge to identify the most commonly found species can be of great help on site. The "ash fraction" value is the key here. These scans measure bone mass, and doctors compare the results with established norms to provide a score. combinations of bone density and shape. Postmenopausal women who are younger than age 65 and at increased risk of osteoporosis as determined by a formal clinical risk assessment tool should also have a BMD test. Here's a table of densities of common substances, including several gases, liquids, and solids. Bone density should also be measured in women between the ages of 50 and 65 who are considered high risk for osteoporosis. This is due to differences in the standard deviations of the young populations. Are you going to sit there and do nothing, or will you prepare for the oncoming attack? According to the US Preventative Services Task Force, DEXA screening is recommended for all men over the age of 70 and all women over the age of 65. The fracture rates go up steeply with age, so any test that is closely related to age will be able to predict that an older person has more fractures than a young person. A peripheral scan is simpler and only involves a small, portable machine. The Z-score does not tell how tall a child is, because the average child gets taller as she gets older. Last medically reviewed on January 14, 2022. You can learn more about how we ensure our content is accurate and current by reading our. This reference group usually consists of people of the same age and gender; sometimes race and weight are also included. Peripheral scans measure bone density in the: DEXA scans are painless and quick. The X-rays measure how much calcium and minerals are in a part of your bone. Bone mass refers to the weight of the skeleton. Disclaimer. Young's modulus of elasticity has been used to calculate the density of hard bone, that is know to be a constant of 1900 kg/m 3. Would you like email updates of new search results? NIH Osteoporosis and Related Bone Diseases National Resource Center. Toll free: 800-624-BONE (2663) Learn more about the causes. Introduction: Lately, the in vitro and in vivo studies on serotonin metabolism have been pointing its influence in bone health.   Mount Sinai School of Medicine Report on Alzheimers Disease, Massachusetts General Hospital Report on Combating Memory Loss. If the address matches a valid account an email will be sent to __email__ with instructions for resetting your password Domestic Animal Physiology 100% (2) 2. University Health News content is medically reviewed or checked to ensure that it is as accurate as possible. FOIA The standard deviations don't change very much with age, so the risk per SD will be the same using T-score or Z-score. . Osteoporotic bone is weaker and subject to fracture. This table shows the meanings of different Z-scores: Dual-energy X-ray absorptiometry (DEXA) scans use a low dose of ionizing radiation to measure bone density. Get Ready for a New Season of Gardening -Choose from Tomatoes, Peaches, Corn, Zinnias & More! Regardless of your sex or age, your doctor may recommend a bone density test if you've: Limitations of bone density testing include: Bone density tests are easy, fast and painless. The NHANES study also reported the standardized units. During the scanning, the person will need to be very still, and the technician might ask them to hold their breath. The reference BMD depends on: For example, this "thermometer" shows the values measured by a Hologic densitometer at the total hip in a Caucasian woman from the NHANES study. The most commonly used BMD test is called a central dual-energy x-ray absorptiometry, or central DXA test. Does Irrigating While Drilling Decrease Bone Damage? Cattle have two hooves leading to the distinctive double cotton reel at the distal end whilst the horses only display a single cotton reel because of the single hoof. As one can see in Figure 10, both dog and cat humerii have a hole (foramen) through the distal articulation. Occasionally, new information on medication is released. The T-score does not necessarily have to compare people of the same race or gender. Use Our Quiz to Find Out! Epub 2013 Oct 9. When the T-score is -1, the bone density is 0.820 no matter how old the person is. . As one can see horse teeth are much squarer in profile and plan compared to cattle teeth with a radically different enamel fold pattern. Pigs have 4 metapodia all unfused compared to a single metapodial in sheep Single fused metapodial. Instead, the T-score was invented. Initially, assessment of volumetric bone mineral density of the four long bone variants was achieved by performing quantitative micro-CT analysis (X Tec, XT H 225 ST, Nikon Metrology UK Ltd, Derby . Is the ketogenic diet right for autoimmune conditions? 8600 Rockville Pike Meaning. The condition can often happen to athletes. The higher your bone mineral content, the denser your bones are. These can be seen in Figure 2. A low standard deviation means that the number is close to the average, and a high standard deviation means that it is further from the average. The early bone density machines in the 1970's and early 1980's all used different kinds of units, so results were reported in Z-scores to allow comparisons to normal people. An athlete has greater bone density than a couch potato. As with cattle this has resulted in a double cotton reel shape at the distal end in sheep. These can be seen in Figure 2. The images go to a computer where a healthcare professional can view them. Furthermore, your risk factors are just as important as your T-score and may lead to better predictions of bone disease. A single copy of these materials may be reprinted for noncommercial personal use only. Cortical femoral bone samples were analyzed for their content of ash, collagen, extractable proteins, and insulin-like growth factor-I. The most useful are listed below: Hillson, S. 2002 Mammal Bones and Teeth: An Introductory Guide to Methods of Identification. Find Bone density chart stock images in HD and millions of other royalty-free stock photos, illustrations and vectors in the Shutterstock collection. This provides an opportunity to reevaluate an individual's . There has been over the years a great deal of spam concerning bone density. A bone mineral density (BMD) test can provide a snapshot of your bone health. Medical News Today has strict sourcing guidelines and draws only from peer-reviewed studies, academic research institutions, and medical journals and associations. At some facilities, you may be asked to change into an examination gown. I agree with you 100% Bold and you are right. T-scores reveal how high or low a persons bone density is compared with that of a typical healthy 30-year-old. Weight-bearing Exercises These exercises include activities that make you move against gravity while staying upright. Your T-score is the number of units called standard deviations that your bone density is above or below the average. Careers. The graph shows the T-scores, calculated from young female reference values, for average men and women from a large meta-analysis (Johnell, ASBMR abstract 2005). Converting the BMD to the T-score is like converting the temperature from degrees Fahrenheit to degrees centigrade: The reference BMD and standard deviation (SD) are to a young person instead of a person the same age as the patient. These risks depend on the population, skeletal site of measurement, technique of measurement, and type of fracture. By comparison, an elderly person, loses about 1 to 2 percent per year. And each year, approximately 80,000 men have a hip fracture. The following differences can help you make the correct identification: Whilst size can be a useful guide initially dont rely on it completely. People who live in mountainous regions normally have greater bone density than those who live on flat ground. As a service to our readers, University Health News offers a vast archive of free digital content. and transmitted securely. Visit our online order form. This site needs JavaScript to work properly. From NE Ohio to North Central Mississippi, everyone has their own ideas and preferences for what they will plant this year. 18, 19 Indeed, the study of Haba et al 20 utilizing impedance spectroscopy . Epub 2022 Nov 2. Having a T-score between -1.0 and -2.5 is not "pre-osteoporosis" or a medical condition, but it is very important for people with low bone density to . DEXA bone scan results scores are measured as T-scores, which is a comparison of a person's bone density with that of a healthy 30-year-old adult. 2023 Feb 3;10(2):201. doi: 10.3390/bioengineering10020201. For various reasons, the DEXA scan is considered the "gold standard" or most accurate test. The greater the negative number, the more severe the osteoporosis. Fractures (Invokana) Fournier's gangrene. Tucker et al. Be sure to tell your doctor beforehand if you've recently had a barium exam or had contrast material injected for a CT scan or nuclear medicine test. The following table gives values from NHANES dataset. Your score is a sign of osteopenia, a condition in which bone density is below normal and may lead to osteoporosis. 5).Therefore, consideration should be given to the measurement of Absolute BMD in Table 2.. Download : Download high-res image (156KB) Download : Download full-size image This step by step guide to archaeological techniques is one of a series prepared by Jigsaw a network of Cambridgeshire groups working alongside Oxford Archaeology East. A doctor can measure a persons bone density with a DEXA scan. Pales, C. and 1971 Atlas Osteologique pour servir a lidentification des Lambert, L. Mammiferes du Quaternaire. The white numbers are at the average values for that age. The instruments used for these tests are called peripheral devices and are often used at health fairs. The fracture risk per Z-score is similar for the femoral neck and the total hip, but the conversion formulas from the T-score at the total hip are not the same as those from the femoral neck. Hairline fractures are small cracks in a bone that occur after stress is placed on the lower leg. Bone density is higher than in others of the same age, sex, and body size. www.nasa.gov Lost in Space: Bone Density 2/5 . Bone density tests differ from bone scans. 3 Decreased facial bone density along with fibrous proliferation is a consistent finding. J Funct Biomater. low production of reproductive hormones, such as: tamoxifen (Nolvadex), a synthetic drug that treats breast cancer and infertility in females. Old Ephraim. It uses very low levels of x-rays to measure how dense your bones are. The test can identify osteoporosis, determine your risk for fractures (broken bones), and measure your response to osteoporosis treatment. Decreased bone density is frequent; however, bone mass must be decreased by 30% before it can be detected radiographically. Unauthorized use of these marks is strictly prohibited. In other words, a normal Z-score only indicates that the bone density is comparable to that of others of the same age, sex, and body size. Radiologic Findings. Cohen, A. and 1991 Manual for the Identification of Bird Bones from Serjeantson, D. Archaeological Sites. A T-score of 2.5 or lower indicates that you have osteoporosis. If someone thinks that they might be pregnant, they should tell the doctor, who will use other diagnostic methods. 222-233, 1996. . In general, based on bone density levels, a repeat bone mineral density measurement could be considered between two and 10 years later. The following table contains the World Health Organization's definitions of osteoporosis based on bone density T-scores. However, as older adults tend to have low bone density, people with normal Z-scores could have osteoporosis. From nutrient deficiencies to disease, there are a number of things that can cause your tomato plants to become sickly or unproductive. Learn more here. Examples are T-scores of -1.1, -1.6 and -2.4. (2020). thank you. Although over the past 10 yr significant advances have been made in the biology of bone cells, especially because of the technical improvements of in vitro systems of bone cell cultures, it has also become clear that such in vitro systems oversimplify the in vivo situation. Bone density loss in astronauts on long-duration missions has been a major medical concern. Download Table | Cortical bone density for each species from publication: The deer femur - A morphological and biomechanical animal model of the human femur | Background: The need for continued . The Biomechanical Stability of Bone Staples in Cortical Fixation of Tendon Grafts for Medial Collateral Ligament Reconstruction Depends on the Implant Design. To better understand the current health of your bones, you should multiply your T-score by 10 percent (as shown in the bone density results chart below). A bone density scan gives a person a Z-score and a T-score. Z-scores can be used to compare a measurement to a reference value. TABLE 2. Cattle belong to the group of mammals known as artiodactyla, (even toed hoofed mammals), whereas horses belong to the group Perissodactyla (odd toed hoofed mammals). Check out these best-sellers and special offers on books and newsletters from Mayo Clinic Press. Figure 6: Sheep (top) and Pig (bottom) skulls. Biosynthetic human parathyroid hormone (1-34) effects on bone quality in aged ovariectomized rats. 1994 Dec;13 Suppl 1:54-62. If your Z-score is significantly higher or lower than the average, you may need additional tests to determine the cause of the problem. 1998-2023 Mayo Foundation for Medical Education and Research (MFMER). National Osteoporosis Foundation. Most experts usually advise the use of Z-scores for children, teenagers, premenopausal females, and males under the age of 50 years. https://www.niams.nih.gov/Health_Info/Bone/Bone_Health/bone_mass_measure.asp. A T-score of -1.0 to -2.5 signifies osteopenia, meaning below-normal bone density without full-blown osteoporosis. 2194 E. R. Dumont Bone density and bird skeletons Proc. For additional information on specific medications, visit Drugs@FDA at https://www.accessdata.fda.gov/scripts/cder/daf. Originally published in 2013, this post is regularly updated. Accessed Nov 25, 2020. Neither one of these scores can predict the fracture risk unless you also know the age. This scan measures bone density at the hip and lower back. The T-score of the QCT, however, will be much lower than of DEXA. A score of -2.5 or less suggests that a person may have secondary osteoporosis, which does not result from aging. Whilst differences in dogs and cats are largely beyond the scope of this introduction it is worth noting a difference in the distal humerus as its robusticity means it is the one of the most commonly found elements on archaeological sites. Phone: 202-223-0344 The .gov means its official. Bone ash is a white material produced by the calcination of bones.Typical bone ash consists of about 55.82% calcium oxide, 42.39% phosphorus pentoxide, and 1.79% water.The exact composition of these compounds varies depending upon the type of bones being used, but generally the formula for bone ash is: Ca 5 (OH)(PO 4) 3.Bone ash usually has a density around 3.10 g/mL and a melting point of . T-scores between -1 and -2.5 indicate that a person has low bone mass, but it's not quite low enough for them to be diagnosed with osteoporosis.