The number of people with untreated oral conditions such as dental caries and severe chronic periodontitis around the world rose from 2.5 billion in 1990 to 3.5 billion in 2015 due to demographic changes, including population growth and aging, according to a study by an international team of researchers. Also, the researchers noted, there was a 64% increase in disability-adjusted life years due to oral conditions during the same timeframe.
The study examined the world’s progress toward goals established by the Federation Dental International, World Health Organization, and International Association for Dental Research to reduce the level of oral diseases globally and minimize their impact by 2020. Despite some challenges with current measurement methodologies, these groups agree that specific measurable oral health goals should be developed to advance global public health.
Oral health did not improve during the 25 years that were studied, the researchers concluded, and oral conditions remained a major and growing global public challenge in 2015. In 2010, the direct treatment costs of these oral conditions totaled approximately $298 billion worldwide, or 4.6% of global health expenditures. The indirect costs totaled $144 billion implant machine. The researchers called for greater efforts and potentially different approaches to meet 2020’s oral health goals.
“Although numerous scientific discoveries and advancements have been achieved to combat and prevent oral health conditions, as a community we know that further efforts are required toward improving oral health worldwide and reducing the global burden of oral diseases,” said Raul Garcia, DMD, president elect of the American Association for Dental Research.
For example, 48% of the world’s population suffers from an oral condition, with 34.1% or 2.5 billion experiencing untreated caries in their permanent teeth in 2015. Also, untreated caries in deciduous teeth affected 573 million children in 2015. Total tooth loss affected 276 million people, peaking between the ages of 75 and 79 years, and severe periodontal disease affected 538 million people, peaking nearly 20 years earlier than total tooth loss.
Missing Teeth Regenerated in Animal Model
Dental implants are now standard solutions for replacing teeth that are lost due to caries, gum disease, or injuries. But we’re another step closer to growing new teeth in their absence, as researchers at Okayama University have demonstrated successful functional tooth restoration via regeneration in a postnatal large-animal model scian nebulizer.
First, the researchers dissected embryonic tooth germ cells and tissues from a beagle 55 days before birth and reconstructed bioengineered tooth germ by means of the organ germ method, which regenerates ectodermal organs by replicating their developmental process starting from a bioengineered organ germ.
Next, these germs were transplanted into mice. In many cases, the germs resulted in tooth-crown formation, featuring both the hard and soft tissues present in natural teeth after several weeks. The researchers also were able to identify the necessary conditions for achieving this success.
Autologous transplantation experiments, which use an organism’s own stem cells instead of relying on a donor to avoid immunological rejection, were then conducted as researchers extracted deciduous teeth from the jawbone of a beagle that was 30 days old. Tooth germ engineered from the dog’s permanent tooth cell and tissue was transplanted after 2 days of cell culture into the dog’s mandible, resulting in tooth eruption 180 days later.
The developmental process of the bioengineered tooth’s formation was practically identical to a natural tooth’s, according to micro-CT analysis. Also, scanning electron microscopy and energy-disruptive x-ray spectroscopy revealed that the bioengineered tooth had the same structure and chemical composition of a natural tooth. Plus, the regenerated tooth’s response to mechanical force was consistent with the proper physiological functioning of the periodontal ligament.
As for human beings, the researchers noted that immature wisdom tooth germ would be a possible source of stem-cell germs, as it is available in the human postnatal jawbone, though this would only pertain to younger people as wisdom teeth mineralize after the age of 7 years. Elderly patients would need other stem-cell sources dental supplies. Still, the researchers believe this work highlights the feasibility of fully functional restoration by autologous transplantation of bioengineered tooth germ.