“The mind of a man is determined by the question rather than the answer he seeks.”
– Voltaire
What could be more controversial than asking a question, let alone the question: do root canals cause cancer? In today’s medicine, the curiosity of the mind that drives questions is discouraged. In some cases, it is outright punished. Controversial, you may ask? Let me take you down a quick memory hole in time from 2019 that will bring us to the question.
Netflix published the documentary Root Cause in 2019. In this documentary, Frazer Baily claimed that root canals were the cause of many diseases, including Cancer. However, Netflix pulled the documentary less than 30 days after its release in 2019. Why? The headlines published at the time provided the obvious firestorm the documentary kicked up. The headline from the Guardian was “Netflix pulls controversial documentary that claims root canals cause cancer.1 And from r/netflix, “Pseudoscience show Root Cause as a documentary.” 2 The firestorm was so intense it burned the documentary down to the ground.
The response to the initial publication by conventional dentistry was also interesting and telling. The UCLA School of Dentistry claimed, “The people in this movie are spreading misinformation and confusion about root canal treatment that is misleading and harmful to the consumer public.” In addition, the PalmBeachPost headline read, “Ignore Netflix Movie; Root Canals are Totally Safe.” 3
What is science? Science is about the open debate and discussion of ideas. I will state the obvious: medicine is a science. Yet, what we see in response to the Root Cause documentary are words and tones that are not typical of an open engagement, debate, and discourse of the science: “quack dentistry,” “pseudoscience,” and the infamous “misinformation.” These words are designed to marginalize, discredit, and malign rather than engage the science to debate and disprove. It reminds me of pre-teens yelling insults on the playground at school. Even Google AI made the declarative statement of Medical consensus that “the scientific and medical communities have stated that root canals are safe and effective.” Consensus is the general agreement or opinion on a particular topic.
Limitations of science
Science and medicine need to change faster. This reluctance to evolve parallel to scientific advancement can be good, and this can be not good. The good: if science changes with the wind and is not driven by the scientific principles of observation, curiosity of mind, questions, scientific discovery, and then open and debate of the science, it reeks of more political narrative than actual science. The response can equally apply. In contrast, if science is slow to change or never changes, it ignores scientific advancement because science always involves discoveries. Discoveries bring change if change and new ideas are allowed.
Modern science and research have been hallmarks of the double blind, randomized controlled trial. Yet, the time and cost associated with this standard limit its broad utilization. As a result, many answers to questions and innovation through discoveries appear to be ground to a halt. This scientific construct limits the open debate and discourse of ideas.
As a result, physicians are left to collect the dots and then connect the dots to engage in debate and discourse of ideas as they present. The scientific process, in the playing field, the players, and the approved dialogue, appears more to control the debate and discourse rather than engage in free, open discussion and discourse of the ideas—science.
Seth Godin, author and entrepreneur, famously said,
“Students today are educated collecting dots. Almost none of it spent teaching the skills necessary to connect dots.”
I call this group thinking and not critical thinking. Seth Godin then closed the loop with the quote,
“Without a doubt, the ability to connect the dots is rare, prized and valuable. Connecting dots, solving the problem that hasn’t been solved before, seeing the pattern before it is made obvious, is more essential than ever before. Why then, do we spend so much time collecting dots instead? More facts, more tests, more need for data, even when we have no clue (and no practice” in doing anything with it. Their big bag of dots isn’t worth nearly as much as your handful of insight, is it?”
There is a bounty of dot collectors, but we all should be dot connectors. The current scientific research construct encourages dot collectors but discourages dot connectors out of fear of challenges to the status quo and public marginalization. The current scientific industry is the arbiter of what is and is not dots, what we can say about these dots, and what dots we are allowed to connect. Doctors are taught to see the protocol rather than to see the pattern. It is through this process that discoveries and innovations are slowed.
Connect the dots
Do root canals cause Cancer? No research published on PubMed or Europe PMC has proven or directly suggested this link, yet these two sites are the dominant research resources in Europe and the U.S. I encourage you to search them yourself.
The origin of this debate, if one can call it a debate as the narrative is one-sided, is from Dr. Weston A Price and his two-volume book, Dental Infections, Oral and Systemic, published in 1923. Dr. Price connected the dots between dental infections and systemic disease, cardiovascular disease, and Cancer in this work. The counter debate to Dr. Price’s theory and published work can be summarized as three fold:
• Lack of rigorous evidence
• Endodontic advancement
• Disproof of bacterial contamination
Infectious disease and cancer
The first is silly. This work was merely a publication of Dr. Weston A Price’s observations. He was collecting the dots, connecting them, and daring to publish them publicly for debate and discourse. He was altruistic and didn’t understand how the science industry works (ahem). The second point, endodontic advancement, is valid. But the third point is where I want to call your attention, and I want to pay particular attention to the connection to Cancer.
Infectious disease is clearly implicated in Cancer. This relationship is more than an association; it is absolute cause and effect.
Infections, including viruses, bacteria, parasites, and fungi, are all directly linked to Cancer. Viruses, such as Epstein-Barr virus (EBV), Human Papillomavirus (HPV), hepatitis B, C, and D (HBV, HCV, HDV), HIV, and Human T-lymphotropic virus-1 (HTLV-1), directly cause 15% of cancers. These viruses are called oncogenic viruses, viruses that cause the development of tumors. The collective link is so strong a 2018 defined the criteria for oncogenic viruses : 4
• Transmission between humans
• Causes chronic infection
• Co-opts cellular processes
• Undermines immune recognition
• Derails signaling pathways
• Supports propagation
Parasites, such as fluke parasites, are less common in the U.S., but their connection to Cancer is strong. Fluke parasites like Opisthorchis viverrini and Clonorchis sinensis can cause cholangiocarcinoma. In contrast, blood flukes like Schistosoma japonicum, mansoni, and haematobium can cause bladder, adenocarcinomas, squamous cell carcinomas, and colorectal Cancer. Plasmodium falciparum, a malaria-causing agent, is linked to Burkett’s lymphoma. Bacteria, such as Helicobacter pylori, can cause stomach ulcers and Cancer. The gut microbiome, influenced by diet, can favor health or disease.
Microbiome and cancer
The gut microbiome and its environment are critical to cancer development and treatment. A recent study found that diet can influence the toxicity potential of chemotherapy by up to 100 fold through alteration of the gut microbiome. The next time you ask your Oncologist about diet in Cancer, they shrug their shoulders, know that diet is the first treatment that dictates treatment toxicity and likely treatment response. A recent study highlights the link between the gut, inflammation, and Cancer. In the presence of a leaky gut, the gut microbiome increases LPS endotoxins, stimulating increases in TLR4 expression in colorectal Cancer. This LPS endotoxin-mediated systemic inflammation leads to increased growth signaling through the Akt/PI3k/mTOR pathway 5 , leading to liver metastasis, which is linked to a 90% cause of morbidity and mortality in Cancer. Lipopolysaccharide borne out of an altered gut microbiome and associated leaky gut is linked to insulin resistance 6, diabetes 7, and Alzheimer’s disease 8 .
Biofilm and cancer
Biofilms are multi-species communities of microorganisms enclosed within a self-constructed matrix of extracellular polymeric substances. They are a biological framework with different microorganisms that cooperate and synergize to ensure survival in harsh environments. Biofilms help seed microorganisms to colonize new locations, similar to how the gut microbiome seeds the tumor microbiome. They significantly contribute to over 80% of infections 9 10 and contribute to Cancer by triggering inflammation, mutagenesis, epigenetic alterations, modulating the host immune response, producing toxins, altering host metabolism, and contributing to multi drug resistance 11. Biofilms are involved in various cancer types, including colon, pancreatic, lung, gastric, gallbladder, breast, ovarian, bone, glioblastoma, and head and neck cancers 12 13 14 .
Can bacteria seed tumors?
Cancer origins and metastasis are linked to the gut microbiome, with bacterial seeding potentially influencing tumor genesis, aggressiveness, and progression. Pancreatic research correlates the seeding of the pancreatic tumor microbiome from the gut microbiome to pancreatic tumor genesis, aggressiveness, and progression. This concept challenges the notion of cancer genesis and metastasis to distant sites, focusing on bacterial seeding of tumors from the gut microbiome rather than tumor cells themselves.
Root canals and bacterial overgrowth
One of the three primary counters to Dr. Price’s theory of root canals and systemic disease, Cancer, is through bacterial overgrowth and infection. Not only is this counterpoint statement out of date, but it is also misinformation. Surprise you? The arbiters of misinformation only come from the originators of the centralized narrative. Still, here, science proves this statement to be out of date and, as a result, misinformation. Yet, the previous statements highlighted at the beginning of the article use the misinformation as disinformation—to deliberately mislead.
The prior point collections of infectious disease and Cancer, microbiome, and Cancer, biofilm and Cancer, and bacterial tumor seeding connect the dots that build a clear connection between bacteria overgrowth and infection in root canals and Cancer. They don’t create a direct cause and effect, but a substantial degree of suspicion. Suppose bacteria from the gut cause Cancer and contribute to cancer progression and metastasis in tumors. In that case, the same or similar action mechanism is likely to be proven elsewhere. But, of course, the gut microbiome has been shown to contribute to carcinogenesis, progression, and metastasis.
Is there evidence of bacterial overgrowth or infection in root canals? If there is evidence to support the existence of bacteria in root canals, then the prior information on the microbiomes is likely to be true. Again, there are no double-blinded randomized placebo-controlled trials here, and there most likely never will be, but we can collect the dots and then connect the dots.
In steps a 2023 article published in the Journal of Clinical Medicine, Root Canal Infection and Its Impact on the Oral Cavity Microenvironment in the Context of Immune System Disorders in Selected Diseases: A Narrative Review 15. This article connects the dots between bacteria in root canals, immune system disruption locally in the oral cavity, chronic inflammation, immune disruption transferred systemically, and the potential development and progression of systemic autoimmune disease, rheumatoid arthritis, systemic lupus erythematosus, and Sjogren’s. They even extrapolate the contribution to chronic kidney disease, Chron’s, and Ulcerative colitis. How hard of a leap is it to take the next step in Cancer?
The original dissenting point of no bacteria or infection in root canals is clearly out of date. Look to the brain to disprove this concept. It has long been felt that the brain is a sterile microenvironment protected by the blood-brain barrier. In steps new discovery, new ideas, and the propagation of science. Could the brain microbiome be fueling Cancer’s metastasis to the brain? A new series of articles on the brain microbiome suggests this point 16 17 18 19 20 21. It is enough to now realize that the human brain is not sterile, but, in fact, it is full of microbes. The more significant implication is that they play a role in neurodegenerative diseases such as Alzheimer’s disease. If they play a role in one disease, microbes can play a role in other diseases like Cancer.
The mechanism of the microbiome’s contribution to Cancer and metastasis to the brain is associated with a breakdown of the blood brain barrier (BBB). It’s hypothesized that microbial components, metabolites, or dysbiosis (an imbalance of microbial populations) could affect the blood-brain barrier, potentially promoting an environment where metastatic cells can cross and colonize. This example resembles the gut epithelial lining disruption and “leaky gut.” The authors of The role of microbiota in metastatic brain tumors provide the closing point 22 ,
“…the enrichment of distinct bacterial and viral taxa within the gut and oral microbiota in brain metastasis patients. Depletion of the gut microbiota in mice decreased tumor growth in the brain…mechanisms to involve alterations in the circulating cytokine profiles and an increase in anti-tumor T cell activity.”
The precedence is clearly present if bacterial overgrowth has been shown to contribute to the carcinogenic process through disruption of the immune system and chronic inflammation, if bacteria outright cause Cancer, and if bacterial seeding from the gut promotes the initiation, progression, and metastasis of pancreatic Cancer, or if the biofilm contributes to the same carcinogenic and progression process.
Conclusion
Is there direct evidence that root canals cause Cancer? Is there a cause and effect? Don’t wait for this mea culpa, as it will never come. There likely will never be a double-blinded, randomized, placebo-controlled trial on the topic of root canals and Cancer. As of now, we are left to collect the dots related to the topic and then connect those dots. Where this is smoke, you can bet there is fire.
If you found the link between root canals and cancer eye-opening, wait until you hear this. Could a biopsy actually spread cancer? While biopsies are considered the gold standard for diagnosis, some research suggests they may release cancer cells into the bloodstream, leading to further complications. If dental infections can play a role in cancer, what about invasive medical procedures?
👉 Read More: Does a Biopsy Cause Cancer to Spread?
Sources
1 Guardian News and Media. (2019, February 28). Netflix pulls controversial documentary that claims root canals cause cancer. The Guardian. https://www.theguardian.com/media/2019/feb/27/netflix-root-cause-pulled-root-canals-cancer
2 R/netflix on reddit: Pseudoscience show “Root cause” masquerades as a documentary. (2019). https://www.reddit.com/r/netflix/comments/ak4d77/pseudoscience_show_root_cause_masquerades_as_a/
3 Sponsored by Mitchell Josephs, D. D. S. (2019, February 8). Story from sponsor-story: Ignore netflix movie; Root Canals are totally safe. The Palm Beach Post.
https://www.palmbeachpost.com/story/sponsor-story/2019/02/10/ignore-netflix-movie-root-canals are-totally-safe/6048351007/
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