Highs and Lows: The Impact of Cannabis on Oral Health

Marijuana—also called cannabis—prepared from the dried flowering tops and leaves of the female plant of Cannabis sativa, is the most widely used illicit drug in the United States. It is estimated that 52.5 million individuals in the US used cannabis in 2021.¹ Further, while cannabis remains illegal on a federal level, emerging state legislative pathways have resulted in an increase in legalization of cannabis for medicinal and recreational use; currently more than 50% of Americans reside in a state that has removed the prohibition of adult use of cannabis.² In previous generations, the primary mode of cannabis use has been smoking, but current cannabis consumption trends include an uptick in vaping and use of other cannabis-containing products (edibles, beverages, oils, concentrates, and topical ointments).¹ Due to widespread prevalence of cannabis use, dental healthcare professionals are likely to encounter individuals who are regular users. In fact, a recent survey indicated that 56% of dentists reported limiting treatment on patients who were high.³ Additionally, 46% of surveyed dentists also reported a need to increase anesthesia when treating patients who were habitual cannabis users.³

The main psychoactive chemical of cannabis is delta-9-tetrahydrocannabinol (Δ9-THC).^4,5 Can-nabis interacts with endogenous cannabinoid receptors, CB1 and CB2. CB1 receptors are found in nerve fibers found in the cerebral cortex, limbic areas, basal ganglia, cerebellum, and thalamic areas, and activation results in the neurological and mental health effects of cannabis.^4,5 CB2 receptors are found in cells in the immune system, predominantly macrophages, and activation results in immunomodulatory effects of cannabis.^4,5 In addition to Δ9-THC, marijuana contains other cannabinoids, including cannabidiol or CBD.⁶ CBD is a nonpsychotropic cannabinoid derived from cannabis and may have therapeutic value, including analgesia, muscle relaxation, anti-inflammatory and anti-allergic effects, apetite stimulation, and antiemesis.⁶ The FDA approved the first drug comprised of an active ingredient derived from marijuana to treat rare, severe epilepsy in June 2018, and ongoing research is investigating the therapeutic uses of other cannabis-derived compounds.⁷ This article seeks to review the current evidence regarding cannabis use and oral health and the clinical implications of cannabis use for patients and dental healthcare professionals.

Epidemiology of Cannabis Use

Cannabis is the most commonly used federally illegal drug in the United States; 52.5 million people, or about 19% of Americans, used it at least once in 2021.^1,8 Reports of use have increased considerably in a pattern that aligns with nationwide legalization efforts. In the period from 2013 to 2023, individuals reporting use of marijuana rose from 7% to 17% and those reporting that they have tried marijuana at least once rose from 38% to 50%. This may represent a true increase in consumption or an increased willingness to report use due to decreased stigma around marijuana. While not all users can be classified as exhibiting disordered use, recent research estimates that approximately 3 in 10 people who use cannabis have cannabis use disorder.⁹ The risk of developing cannabis use disorder has been reported to be greater for individuals who begin to use it before age 18.¹⁰

Nine percent of U.S. adults would be classified as “regular cannabis users”—defined as at least 10 days of consumption per month.¹¹ Regular usage differs by education, household income, and age.¹¹ The highest rates of regular cannabis consumption are seen among those with a high school education or less (13%) and those living in households earning less than $24,000 per year (16%).¹¹ Such rates of regular cannabis use are more than three times the rates found among those with postgraduate degrees (5%) and those living in households earning $180,000 or more annually (5%).¹¹ Additionally, adults under 50 years of age are twice as likely as those aged 65 and older to be regular cannabis users.¹¹ There are not statistically significant differences in cannabis use between racial/ethnic groups, and males are slightly more likely to be regular cannabis users than females (11% versus 8%, respectively).¹¹ Geographic differences in regular use are also statistically significant.¹¹ The highest rates of use (11%) are found in the Middle Atlantic (New York, Pennsylvania, and New Jersey) and East North Central geographic areas (Wisconsin, Michigan, Illinois, Indiana, and Ohio).¹¹ The lowest usage rates (7%) are reported in the East South Central (Kentucky, Tennessee, Mississippi, and Alabama) and the West North Central (North Dakota, Minnesota, South Dakota, Nebraska, Iowa, Kansas, and Missouri) regions.¹¹ Interestingly, state-level legalization of cannabis was not significantly associated with percentage of regular cannabis users in the states nor with mean days per month of cannabis use.¹¹

Methods of cannabis consumption are also changing. While smoking of inhalational cannabis continues to be the most common form of cannabis use, an increasing percentage of individuals who report using cannabis report intake via vaping and edible use. One study showed that between 2017 and 2019, the rate of vaping as the primary form of cannabis consumption increased by approximately 5%, from 9.9% to 14.9% of users.¹² Further, the popularity of edible forms of cannabis have increased considerably. National data suggest 30% of adults and 47% of 18- to 34-year-old marijuana users have consumed marijuana in edible form.^13,14 Rates of edible consumption were higher in states with legalized recreational marijuana compared with those with legalization for medical use only or no legalization.¹⁴ It is important for dental healthcare professionals to understand the epidemiologic trends in cannabis use so that they can address the needs of their patients who may consume marijuana in various forms.

Cannabis Pharmacology

The main psychoactive chemicals in cannabis products are delta-9-tetrahydrocannabinol (Δ9-THC) and cannabidiol (CBD). The pharmacologic effects of each of these compounds is quite distinct. For example, CBD does not produce acute intoxication and may have anti-inflammatory, anxiolytic, and antipsychotic indications. It has also been used to treat severe refractory epilepsy in children.¹⁵ Δ9-THC, on the other hand, produces the acute intoxication associated with the recreational use of cannabis and has been further shown to result in undesirable effects, such as paranoia, memory impairment, increased risk of psychotic illness, and cannabis dependency in some users.¹⁵ Signs of acute Δ9-THC intoxication are summarized in Table 1. It should be noted that recent investigations have also highlighted the potential analgesic effect of Δ9-THC.¹⁵ Both Δ9-THC and CBD exert their effects on the body by interactions with endogenous cannabinoid receptors, CB1 and CB2.^16,17 In the absence of the application of exogenous cannabis, these receptors modulate neuronal activity by altering secondary neurotransmitters and the ion transport system. CB1 and CB2 receptors are both polypeptide membrane proteins that inhibit adenylate cyclase and calcium channels while they simultaneously open potassium channels.^16,17 CB1 receptors are found primarily in the cerebral cortex, limbic areas, basal ganglia, cerebellum, and thalamic areas of the brain and when acted upon by cannabis reults in activation of receptors that regulate pleasure, memory, thoughts, concentration, sensory, time perception, and coordination of voluntary movements.^16,17 CB2 receptors are predominantly expressed in immune system cells, and their activation modulates cytokine release and cell migration. Cell types that express CB2 receptors include neutrophils, macrophages, B and T lymphocytes, monocytes, and mastoid cells.^16,17 In many cannabis products the ratio of Δ9-THC to CBD have been shown to impact the psychoactive and therapeutic potential of the cannabis product. It is thus interesting to note that the majority of both medical and recreational cannabis products (72% to 100%) in a recent market survey demonstrate the most intoxicating ratio category of THC to CBD (Δ 1:1 Δ9-THC:CBD).¹⁵ Further, cannabis products without CBD contained the highest percentage of Δ9-THC (>15%).¹⁵ This could reflect that consumers may be unaware of the potency of products that they are consuming.

The mode of consumption may also impact the onset and duration of symptoms. Consuming foods containing cannabis or cannabis-derived compounds, e.g., Δ9-THC, is associated with slower onset of psychoactive effects, which can be delayed by one to three hours compared to inhalational (smoking and/or vaping) methods of cannabis consumption.¹⁸ Researchers have noted that use of cannabis edibles can prolong the duration of psychoactive effects and may potentially heighten risk of inadvertent overconsumption.¹⁹ Additionally, in 2022, the FDA issued a consumer alert²⁰ that advised adults to keep cannabis edible products away from young children, due to concerns about poisoning from accidental ingestion. In fact, reported poisoning of children due to edible cannabis consumption increased 1,375% between 2017 and 2021.²¹

Cannabis and Oral Health

The use of cannabis, particularly marijuana smoking, has been associated with poor quality of oral health, but determination of direct causation is complicated by the number of associated factors with frequent users, including: concomitant use of tobacco, alcohol, and other drugs; poor oral hygiene practices; and infrequent visits to dentists.^22-25 It has been noted that gingival conditions, including leukoplakia, leukoedema, gingival enlargement, oral dysplasia, hyperkeratosis, and even oral neoplasms are more common in individuals who use cannabis, particularly those who consume marijuana by smoking.^18,25-27 Further, incidence and severity of periodontal diseases have been associated with cannabis smoking.^17,28-31

Cannabis and Dental Caries

The rates of dental caries, particularly smooth surface caries, have been shown to be increased in individuals who report cannabis use.^{18,22-25,32,33} There are potentially myriad reasons for these differences. Δ9-THC is an appetite stimulant and has been associated with increased carbohydrate consumption. In several studies individuals who use cannabis report decreased frequency of toothbrushing and less regular dental visits compared to those who did not use marijuana.³⁴ Consumption of Δ9-THC is also associated with an increased rate of transient xerostomia that has been shown to persist for approximately 16 hours after the use of cannabis.²⁵ Dry mouth symptoms were also noted in 69.6% of individuals after smoking cannabis compared with 18.6% of individuals after smoking tobacco.³⁵ Further, because socio-economic status and, therefore potentially, access to dental care has been linked to increased cannabis consumption, some studies have found that increases in caries rates in individuals who use cannabis are not statistically significant when confounders such as education level, age, and household income are considered.^36,37

Cannabis Use and the Periodontium

Cannabis smoking has long been associated with increased rates of periodontitis.^17,28-31 In a large longitudinal cohort study, periodontitis incidence at 32 years old among cannabis consumers was 19.3%.³⁸ Further, individuals who had the highest levels of cannabis consumption demonstrated a significantly higher rate of development of new cases of periodontitis (relative risk 1.61 [95% CI 1.16-2.24]).³⁸ It has been postulated that the deeper inhalation and prolonged contact with cannabis products and byproducts and the absorption times of these chemicals contribute to the etiology of periodontal disease. Many of the deleterious effects of cannabis on the periodontium have been associated with the combustion products produced during cannabis smoking rather than the active ingredients in cannabis themselves.³⁹ It should be noted that studying the effects of the combustion products can be challenging in a population cohort due to the confounding potential of concurrent tobacco consumption.⁴⁰ Because much of the negative impact of cannabis use has been associated with smoking and/or vaping byproducts, it is important for the dental healthcare professional to be aware not only of cannabis consumption frequency and amount, but also mode of consumption. Currently, smoking continues to be the predominant method of cannabis consumption, with individuals who consume cannabis three times more likely to smoke versus consume edibles.⁴¹ The main active ingredients in cannabis, cannabinoids, have been associated with the suppression of important biological pathways related to inflammation^42,43 and have also been proposed as therapeutic targets for adjunctive use with periodontal therapy.^16,44,45 In animal models, CBD application has been found to attenuate bone and attachment loss associated with ligature-induced periodontitis^44,46 and cannabidiol essential oils have been identified as having antimicrobial properties.^47-49 CBD has also been used in both animal and human models an adjuncts to improve outcomes of periodontal regeneration, including alveolar bone gain.^16,50,51 Further research is necessary to better elucidate the therapeutic properties of cannabis and their utility in periodontal therapy.

Clinical Implications of Cannabis Use in Dental Patients

It has been reported that approximately 3 in 4 dentists do not ask patients about a history of cannabis use.⁵² Inclusion of probative analysis of cannabis use as a part of medical and social history taking for dental patients is critically important, as such use can impact oral health, drug-drug interactions, and therapeutic outcomes for dental care. It is important for dental healthcare professionals to know if a patient uses cannabis, in what forms, and the dosages and frequency of use, as this will allow them to better assess increased risk for oral conditions and diseases. Further, cannabinoids have been identified as inhibitors of liver enzymes, including CYP2C19 and CYP3A4/5, which can impact other medications that patients are taking that impact dental care delivery, including warfarin and clobazam.⁵³ Cannabis has also been reported to have additional drug-drug interactions with antifungals, anti-inflammatory medications, antibiotics, analgesics, and sedative agents, impacting their clearance, potency, and duration of action.^53,54 Further, while case reports and anecdotal evidence have suggested that individuals who regularly use cannabis may require increased dosages of local anesthetic to achieve profound anesthesia for dental procedures,⁵⁵ definitive data are not available to substantiate these claims.⁵⁶

Effects of acute intoxication and their interferences with delivery of dental care are also important for dental healthcare professionals to recognize. It has been recently reported that more than half of dentists surveyed reported patients arriving to appointments high on marijuana or other drugs.³ Δ9-THC has been shown to be associated with sinus tachycardia, atrial fibrillation, and hypertension, among other cardiovascular complications.⁵⁷ Further, there is evidence to suggest that increased frequency of marijuana use increases the risk of cardiac arrhythmias and myocardial infarction (MI) in regular users.^58-60 The incidence of cardiovascular complications has been estimated to be between 0.5% and 2% in individuals who were acutely intoxicated with cannabis products.^61,62 Current recommendations include assessment of cannabis use prior to the delivery of dental care and avoiding elective dental care in patients for 24 hours after cannabis intoxication to reduce the risk of adverse events.⁶³ Table 1 summarizes the recommendations for dental healthcare providers when cannabis use and/or acute intoxication is suspected in the dental office.

Therapeutic Use of Cannabis for Oral Conditions

Preliminary data suggest that the endocannabinoid system and the impacts of cannabinoids on periodontal tissues suggest that there may be therapeutic uses, including immunomodulatory and antimicrobial properties that could potentially serve as adjuncts to therapies for periodontal healing and tissue regeneration.¹⁶ In animal models cannabidiol has been shown to attenuate periodontal inflammation when applied topically.⁴⁴ Further, intravenous administration of cannabidiol has been shown to mitigate bone loss in a ligature-induced periodontal inflammatory model.⁶⁴ Future research focusing on the therapeutic impacts of cannabinoid compounds for individuals with dental diseases and/or those who are undergoing dental therapies is needed.

The Dental Professional and Cannabis

Despite the number of states that have legalized cannabis use for either medical or recreational reasons, the use of marijuana continues to be federally illegal. Use of marijuana or Δ9-THC-containing products by a licensed dental healthcare professional continues to be problematic. All dental boards, including those in states with legal, recreational marijuana use, strictly prohibit dental healthcare professionals from treating patients while impaired. Further, employers have a right in all states to establish drug-free workplace policies, and most have such policies in place for safety-sensitive healthcare workplaces. Dental boards offer diversion programs for dentists, registered dental assistants, and dental hygienists whose marijuana or other drug use turns into a substance abuse problem. The ADA has created a Dentist Well-Being Programs Handbook for dentists dealing personal impairment.⁶⁵ Further, the ADA recommends that dental offices adopt a drug-free workplace policy to help manage office safety and provide more tools for managing office staff drug-related issues and provides a sample drug-free workplace policy for offices to use as a template.⁶⁶

Summary

With the growing use of cannabis and cannabis derivatives nationwide, dental professionals may treat higher numbers of patients with a history of cannabis use and those who may report side effects of cannabis use, including effects on the oral cavity. A thorough understanding of the impacts of cannabis on oral and overall health as well as continued assessment of current state law changes related to cannabis consumption are critical to allow the dental healthcare team to provide safe and effective treatment to all patients.

References

1. Centers for Disease Control and Prevention. Marijuana and Public Health. Available at: https://www.cdc.gov/marijuana/index.htm#:~:text=Marijuana%E2%80%94which%20can%20also%20be,people%20using%20it%20in%202019.  Accessed September 15, 2024.

2. Carnevale Associates. Status of State Cannabis Legalization: November 2023. Available at: https://www.carnevaleassociates.com/our-work/status-of-state-cannabis-legislation-november-2023.html  Accessed September 15, 2024.

3. American Dental Association Press Release. “Half of Dentists Say Patients Are High at Dental Appointments. Marijuana Use May Affect Oral Health and Treatment.” Available at: https://www.ada.org/en/about/press-releases/half-of-dentists-say-patients-are-high-at-dental-appointments  Accessed September 15, 2024.

4. Quaranta A, D’Isidoro O, Piattelli A, Hui WL, Perrotti V. Illegal drugs and periodontal conditions. Periodontol 2000 2022; 90: 62-87.

5. Iversen L. Cannabis and the brain. Brain 2003; 19(3): 293-300.

6. Grotenhermen F. Pharmacology of cannabinoids. Neuro Endocrinol Lett 2004; 25: 14-23.

7. US Food and Drug Administration. FDA Regulation of Cannabis and Cannabis-Derived Products, Including Cannabidiol (CBD). Available at: https://www.fda.gov/news-events/public-health-focus/fda-regulation-cannabis-and-cannabis-derived-products-including-cannabidiol-cbd#:~:text=The%20FDA%20has%20approved%20Epidiolex,years%20of%20age%20and%20older.  Accessed September 15, 2024.

8. Substance Abuse and Mental Health Services Administration. Key substance use and mental health indicators in the United States: Results from the 2021 National Survey on Drug Use and Health (HHS Publication No. PEP22-07-01-005, NSDUH Series H-57). Center for Behavioral Health Statistics and Quality, Substance Abuse and Mental Health Services Administration. 2022. https://www.samhsa.gov/data/report/2021-nsduh-annual-national-report. Accessed on September 15, 2024.

9. Hasin DS, Saha TD, Kerridge BT, et al. Prevalence of marijuana use disorders in the United States between 2001-2002 and 2012-2013. JAMA Psychiatry. 2015; 72(12): 1235-1242.

10. Winters KC, Lee C-YS. Likelihood of developing an alcohol and cannabis use disorder during youth: Association with recent use and age. Drug Alcohol Depend. 2008; 92(1-3): 239-247.

11. Gallup News. Cannabis Use Greatest Among Lower-Income and Less Educated. Available at: https://news.gallup.com/poll/642851/cannabis-greatest-among-lower-income-less-educated.aspx#:~:text=Adults%20younger%20than%2050%2C%20for,White%2C%20Black%20and%20Hispanic%20adults.  Accessed September 15, 2024.

12. Centers for Disease Control and Prevention. BRFSS Prevalence and Trends Data. Available at: https://www.cdc.gov/brfss/brfssprevalence/index.html  Accessed September 15, 2024.

13. Schauer GL, King BA, Bunnell RE, Promoff G, McAfee TA, 2016. Toking, vaping, and eating for health or fun: Marijuana use patterns in adults, U.S. Am J Prev Med. 2014; 50(1): 1–8.

14. Steigerwald S, Wong PO, Cohen BE, Ishida JH, Vali M, Madden E, Keyhani S, Smoking, vaping, and use of edibles and other forms of marijuana among U.S. adults. Ann Intern Med. 2018; 169(12): 890–892.

15. Pennypacker SD, Cunnane K, Cash MC, Romero-Sandoval EA. Potency and Therapeutic THC and CBD Ratios: US Cannabis Markets Overshoot. Frontiers in Pharmacology 2022; 13: 921493.

16. Rendón YC, Garzón HS, Bueno-Silva B, Arce RM. Cannabinoids in Periodontology: Where Are We Now? Antibiotics 2023; 12: 1687.

17. Quaranta A, D’Isidoro O, Piattelli A, Hui WL, Perrotti V. Illegal Drugs and Periodontal Conditions. Periodontol 2000 2022; 90: 62-87.

18. Joshi S, Ashley M. Cannabis: A joint problem for patients and the dental profession. Br Dent J 2016;220(11):597-601.

19. Peralt A, Ke P, Castaneto MS. Impact of cannabis-infused edibles on public safety and regulation. J Forensic Sci 2022;67(6):2387-93.

20. U.S. Food and Drug Administration. FDA warns consumers about the accidental ingestion by children of food products containing THC. 2022. "https://www.fda.gov/food/alerts-advisories-safety-information/fda-warns-consumers-about-accidental-ingestion-children-food-products-containing-thc". Accessed September 15, 2024.

21. Tweet MS, Nemanisch A, Wahl M. Pediatric Edible Cannabis Exposures and Actue Toxicity: 2017-2021. Pediatrics 2023; 151(2). e2022057761.

22. Schulz-Katterbach M, Imfeld T, Imfeld C. Cannabis and caries--does regular cannabis use increase the risk of caries in cigarette smokers? Schweizer Monatsschrift fur Zahnmedizin = Revue mensuelle suisse d'odonto-stomatologie 2009;119(6):576-83.

23. Rawal SY, Tatakis DN, Tipton D. Periodontal and oral manifestations of marijuana use. Journal of the Tennessee Dental Association 2012;92(2):26.

24. Versteeg PA, Slot DE, van der Velden U, van der Weijden GA. Effect of cannabis usage on the oral environment: a review. Int J Dent Hyg 2008;6(4):315-20.

25. Cho CM, Hirsch R, Johnstone S. General and oral health implications of cannabis use. Aust Dent J 2005;50(2):70-4.

26. Maloney WJ, Raymond GF. Common substances and medications of abuse. In: O'Neil M, editor. The ADA Practical Guide to Substance Abuse Disorders and Safe Prescribing. Hoboken, NJ: John Wiley & Sons, Inc.; 2015.

27. Alexander-Savino CV, Mirowski GW, Culton DA. Mucocutaneous Manifestations of Recreational Drug Use. Am J Clin Dermatology 2024; 25(2):281-297.

28. Darling MR. Cannabis abuse and oral health care: review and suggestions for management. SADJ 2003; 58(5): 189-190.

29. Chisini LA, Cademartori MG, Francia A, et al. Is the use of cannabis associated with periodontitis? A systematic review and meta-analysis. J Periodontal Res 2019;54(4):311-17.

30. Mayol M, Andrade E, Rivoir SP, Rossy LAB, Rosing CK. Periodontal status in cannabis smokers. A systematic review. J Int Acad Periodontol 2021;23(2):150-66.

31. Keboa MT, Enriquez N, Martel M, Nicolau B, Macdonald ME. Oral health implications of cannabis smoking: a rapid evidence review. J Can Dent Assoc 2020;86:k2.

32. Yazdanian M, Armoon B, Noroozi A, et al. Dental caries and periodontal disease among people who use drugs: a systematic review and meta-analysis. BMC Oral Health 2020;20(1):44.

33. Bellocchio L, Inchingolo AD, Inchingolo AM, et al. Cannabinoids drugs and oral health—from recreational side-effects to medicinal purposes: a systematic review. International Journal of Molecular Sciences 2021;22(15):8329.

34. Schulz-Katterbach MS . Cannabis and caries does regular cannabis use increase the risk of caries in cigarette smokers? Zurick Open Repos Arch 2009; 119: 576–583.

35. Darling M R, Arendorf T M . Effects of cannabis smoking on oral soft tissues. Community Dent Oral Epidemiol 1993; 21: 78–81.

36. Helmi M, Aldawood A, Al-Otaibi M, Alnassar E, Al Subaie A, Aldosari M. Oral health status among recreational cannabis (marijuana and hashish) users in the USA: A NHANES-based cross-sectional study. Saudi Dental Journal 2024; 36(4): 596-602.

37. Samman M, Scott T, Sohn W. The Effect of Marijuana-Smoking on Dental Caries Experience. International Dental Journal 2024; 74(4): 862-867.

38. Thomson WM, Poulton R, Broadbent JM, et al. Cannabis smoking and periodontal disease among young adults. J Am Med Assoc 2008; 229(5): 525-531.

39. Lopez R, Baelum V. Cannabis use and destructive periodontal diseases among adolescents. J Clin Periodontol 2009; 36(3): 185-189.

40. Johnson GK, Slach NA. Impact of tobacco use on periodontal status. J Dent Educ 2001; 65(4): 313-321.

41. Drive Research. What Percentage of Americans Consume Edibles? Available at: https://www.driveresearch.com/percentage-americans-consume-edibles/  Accessed September 15, 2024

42. Melamede R. Harm-reduction—the cannabis paradox. Harm Reduct J 2005; 2: 17.

43. Melamed R. Cannabis and tobacco smoke are not equally carcinogenic. Harm Reduct J 2005; 2: 21.

44. Chen H, Liu Y, Yu S, Li C, Gao B, Zhou X. Cannabidiol attenuates periodontal inflammation through inhibiting TLR4/NF-pathway. J Periodont Res 2023; 58: 697-707.

45. David C, Elizalde-Hernández A, Barboza AS, Cardosa GC, Santos MBF, Moraes RR. Cannabidiol in Dentistry: A Scoping Review. Dent J 2022; 10: 193.

46. Gu Z, Singh S, Niyogi RG, Lamont GJ, Wang H, Lamont RJ, Scott DA. Marijuana-Derived Cannabinoids Trigger a CB2/PI3K Axis of Suppression of the Innate Response to Oral Pathogens. Front Immunol 2019; 10: 2288.

47. Wasim K, Haq I, Ashraf M. Antimicrobial studies of the leaf of Cannabis sativa L. Pak. J Pharm Sci 1995; 8: 29-38.

48. Nissen L, Zatta A, Stefanini I, Grandi S, Sgorbati B, Biavati B, Monti A. Characterization and antimicrobial activity of essential oils of industrial hemp varieties (Cannabis sativa L.) Fitoerapia 2010; 81: 413-419.

49. van Klingeren B, ten Ham M. Antibacterial activity of Δ9-trathydrocannabinol and cannabidiol. Antonie Van Leeuwenhoek 1976; 42: 9-12.

50. Napimoga MH, Benatti BB, Lima FO, Alves PM, Campos AC, Pena-Dos-Santos DR, Severina FP, Cunha FQ, Guimarães FS. Cannabidiol decreases bone resorption by inhibiting RANK/RANKL expression and pro-inflammatory cytokines dring experimental periodontitis in rats. Int Immunopharmacol 2009; 9: 216-222.

51. Hu Z, Qin Z, Xie J, Qu Y, Yin L. Cannabidiol and its application in the treatment of oral diseases: therapeutic potentials, routes of administration and prospects. Biomed Pharmacother 2024; 176: 116271.

52. Chaffee BW, Urata J, Couch ET, Silverstein S. Dental Professionals' Engagement in Tobacco, Electronic Cigarette, and Cannabis Patient Counseling. JDR Clin Trans Res.2019; 2380084419861384.

53. Antoniou T, Bodkin J, Ho JMW. Drug interactions with cannabinoids. CMAJ 2020; March 2; 192: E206.

54. Mittleman M, Lewis R, Maclure M, Sherwood J, Muller J. Triggering myocardial infarction by marijuana. Circulation 2001; 103(23): 2805-2809.

55. Kimbrough HM., Jr Local anesthetic and the addictive patient. Tex Dent J 1975;93:7–9.

56. Moran MC, Heaton LJ, Leroux BG, Flake NM. Local Anesthetic Efficacy in Marijuana Users and Nonusers: A Pilot Study. Anesth Prog. 2022 Dec 1;69(4):15-21.

57. Pasha AK, Clements CY, Reynolds CA, Lopez MK, Lugo CA, Gonzalez Y, Shirazi FM, Abidov A. Cardiovascular Effects of Medical Marijuana: A Systematic Review. Am J Medicine 2021; 134(2): 182-193.

58. Hart CL, van Gorp W, Haney M, Foltin RW, Fischman MW. Effects of acute smoked marijuana on complex cognitive performance. Neuropsychopharmacology. 2001; 25: 757–765.

59. Fant RV, Heishman SJ, Bunker EB, Pickworth WB. Acute and residual effects of marijuana in humans. Pharmacol Biochem Behav. 1998; 60: 777–784.

60. Subramaniam VN, Menezes AR, DeSchutter A, Lavie CJ. The Cardiovascular Effects of Marijuana: Are the Potential Adverse Effects Worth the High? Mo Med. 2019; 116(2):146-153.

61. Gresnight F, van den Brink LC, Hunault C, Franssen E, de Lange D, Riezebos R. Incidence of cardiovascular symptoms and adverse events following self-reported acute cannabis intoxication at the emergency department: a retrospective study. Emergency Medicine Journal 2023; 40: 357-358.

62. Jeffers AM, Glantz S, Beyers AL, Keyhani S. Association of Cannabis Use with Cardiovascular Outcomes Among US Adults. J Am Heart Assoc 2024; 13(5): https://doi.org/10.1161/JAHA.123.030178

63. ADA Oral Health Topics: Cannabis: Oral Health Effects. Available at: https://www.ada.org/resources/ada-library/oral-health-topics/cannabis-oral-health-effects#:~:text=Due%20to%20concerns%20such%20as,patient98%20or%20postponing%20non%2D  Accessed September 15, 2024.

64. Silveira JW, Issy AC, Castania VA, Salmon CEG, Nogueira-Barbosa MH, Guimarães FS, et al. (2014) Protective Effects of Cannabidiol on Lesion-Induced Intervertebral Disc Degeneration. PLoS ONE 9(12): e113161.

65. American Dental Association Council on Dental Practice: Dentist Well-Being Programs Handbook. Available at: chrome-extension://efaidnbmnnnibpcajpcglclefindmkaj/https://dentistwellbeing.com/pdf/topics_wellbeing_handbook.pdf. Accessed September 15, 2024.

66. American Dental Association Council on Dental Practice: Drug-Free Workplace Policies. Available at: chrome-extension://efaidnbmnnnibpcajpcglclefindmkaj/https://toplawyer.law/wp-content/uploads/2021/10/ADA-Sample-Drug-Free-Workplace-Policy.pdf. Accessed September 15, 2024.