Brains, Teeth May Have Not Co-Evolved

A new study from the George Washington University Center for the Advanced Study of Human Paleobiology suggests that human brains and teeth did not evolve in lockstep and were likely influenced by different ecological and behavioral factors.
This research published in the January issue of Proceedings of the National Academy of Sciences challenges the classically accepted view that reduction of tooth size in hominins is linked with having a larger brain. The reasoning is that the larger brains allowed hominins to start making stone tools, which helped reduce the need for large chewing teeth. But recent studies by other authors found that hominins had larger brains before chewing teeth became smaller, and they made and used stone stools when brains were still quite small, which challenges this relationship.
The new study evaluates this issue by measuring and comparing the rates at which teeth and brains have evolved along the different branches of the human evolutionary tree. Researchers analyzed eight different hominin species, identifying fast-evolving species by comparing differences between groups with those obtained when simulating evolution at a constant rate across all lineages. They found clear differences between tooth evolution and brain evolution.
Considering the classical view that proposes co-evolution, researchers expected to see a close correspondence between species evolving at a fast rate for both traits. The differences they observed indicate that diverse and unrelated factors influenced the evolution of teeth and brains.
This article is cited by Journal of California Dental Association, Volume 45, N° 4. April 2017.
For more about this study, see the proceedings of the National Academy of Sciences 114(3)468-473(2017).

Surgeon General Report: E-Cigarette Use Is A “Major Public Health Concern.”

The ADA News (12/8, Manchir) reports that the US Surgeon General said in a report released Dec. 7 that e-cigarette use among youth has been increasing in recent years at an “alarming rate,” and public health professionals, parents, and others must work together to address it. “All Americans need to know that e-cigarettes are dangerous to youth and young adults,” said US Surgeon General Dr. Vivek H. Murthy in a news release about the report. “We need parents, teachers, health care providers and other influencers to help make it clear that e-cigarettes contain harmful chemicals and are not okay for kids to use.”

The surgeon general’s office also in December launched a new, consumer friendly website, E-cigarettes., aimed at educating parent and adult influencers of young people about e-cigarette use.

This article is re-posted from ADA Morning Huddle. For more information about the ADA’s involvement in tobacco issues, visit

New York Post: Oral Health Issues May Indicate “Serious Health” Problems.

The New York Post (12/6, Shea) reports that oral health issues can indicate “serious health issues,” ranging from “digestive troubles to diabetes.” The article discusses what health conditions may be revealed by problems with gums, teeth, saliva, lips, and breath. For example, xerostomia may be an indicator of Sjögren’s syndrome, while red and bleeding gums may be a sign of gum disease or diabetes. In another example, the article reports that halitosis may result from poor oral hygiene practices but could also be a sign of acid reflux.
TIME (12/6) carries a article that also discusses the association between poor oral health and other health conditions, stating “research suggests that the condition of your gums is connected to a variety of health issues,” such as heart disease. The article stresses the importance of cleaning between teeth every day to remove debris and help prevent plaque buildup.
The Oral Health Topics on and provide additional information on xerostomia for dental professionals and for patients. also provides information for patients on gum disease, diabetes and oral health, halitosis, heart disease and oral health, and flossing, including the correct flossing technique.

(Re-post from ADA Morning Huddle)

Study Finds Association Between Poor Oral Health And Heart Disease.

Prevention Magazine (11/2) carries the story first published in Men’s Health reporting that a new study from Finland suggests poor oral health may affect heart health. Researchers examined “the teeth and the arteries of more than 500 people,” finding that those needing a root canal were “nearly three times more likely to have acute coronary syndrome” than “patients with healthy teeth.” Study author Dr. John Liljestrand suggests the bacteria from the tooth infection may spread to other parts of the body, including the heart. Dr. Liljestrand recommends brushing twice a day, flossing daily, and regular dental visits to help reduce the risk of tooth decay. provides additional information on root canal treatment, oral health, and heart disease and oral health.

Dentist Uses Smartphone To Create 3D-Printed Face Prosthesis For Cancer Survivor.

Dentist Uses Smartphone To Create 3D-Printed Face Prosthesis For Cancer Survivor.
The New York Post (11/2, Tousignant) reports that Dr. Rodrigo Salazar, a dentist and specialist in oral rehabilitation, used a smartphone and low-cost printer to create a 3D-printed face prosthesis for Carlito Conceiao, of Sao Paulo, Brazil. In 2008, Conceiao was diagnosed with upper maxillary carcinoma, an “aggressive mouth cancer that damaged his throat and destroyed facial tissue.” While surgeons were able to operate before the cancer spread to Conceiao’s brain, the surgery required removing one of Conceiao’s eye sockets and part of his nose.
The Daily Mail (11/2, Mailonline) reports that for the “ground-breaking procedure,” Dr. Salazar from Paulista University (UNIP) in Sao Paulo used a free smartphone app called Autodesk 123D Catch to turn photos into the 3D model used to create the prosthesis. “We’ve developed an alternative and simplified low-cost procedure that captures patients’ facial anatomy and generates physical working models, giving us the equivalent results to prostheses produced on state-of-the-art equipment that costs hundreds of thousands of pounds,” said Dr. Salazar, who has been leading the project for two years. and the Oral Health Topics on provide information on oral and oropharyngeal cancer for patients and for dental professionals.

Researchers Find Associations Between Gum Disease And Several Health Problems.


The Washington Post (10/1, Levingston) reported that researchers are finding potential links “between gum or periodontal disease” and several different types of health problems. Although “experts are far from understanding what these links might mean,” the “links between gum disease and diabetes, at-risk pregnancy, heart disease and stroke have been so consistent that some insurers offer extra preventive periodontal care at little or no cost to people with those conditions.” The article pointed out that according to the CDC “nearly half of all Americans age 30 and older have some form of gum disease; in people 65 and older, 70 percent have some degree of periodontal disease.” The article noted, “Signs of gum disease include bleeding, red or swollen gums; areas where the gum seems separated from the teeth; bad breath; and loose teeth, which can cause changes in your bite, according to the American Dental Association.” also provides information for patients gum disease, heart disease and oral health, and diabetes and oral health.

Governor Signs Historic Package of Bills Restricting Tobacco Use

Gov. Jerry Brown has signed a package of five bills that are the most significant set of tobacco restrictions in years. Brown signed:
■ SB 5 X2 by Sen. Mark Leno classifies e-cigarettes as tobacco products. This will make them subject to smoke-free laws, age restrictions and other rules governing tobacco products.
■ SB 7 X2 by Sen. Ed Hernandez and Assemblymember Jim Wood, DDS, raises the age to buy tobacco products from 18 to 21.
■ AB 7 X2 by Assembly member Mark Stone closes loopholes in the state’s smoke-free workplace laws.
■ AB 9 X2 by Assembly members Tony Thurmond and Adrin Nazarian requires all schools to be tobacco-free.
■ AB 11 X2 by Assembly member Nazarian establishes a tobacco licensing fee program under the state Board of Equalization.
“These bills are the most significant set of tobacco restrictions in years and we thank the governor and Legislature for taking this historic step,” CDA President Ken Wallis, DDS, said.” “Dentists see the devastating effects of tobacco use every day and we are very pleased that California has taken bold steps to protect our residents from these deadly products.”
California becomes the second state, after Hawaii, to raise the smoking age to 21. More than 100 cities, including San Francisco, have also passed this policy. The state also joins a growing number of states regulating e-cigarettes like tobacco products in order to combat the exploding use of e-cigarettes by teens.
Published by CDA JOURNAL, VOL 4 4 , Nº 7, JULY 2016