By Nancy W. Burkhart, BSDH, EdD
The use of smokeless tobacco and its effect on the oral tissues is a primary issue in the United States, as well as throughout many other countries. It is known that the long-term use of certain types of smokeless tobacco does result in oral cancer. These include but are not limited to the betel quid with tobacco in India, khat in Yemen, gul powder in Bangladesh, Chimo in Venezuela, and, of interest to this report, the toombak in Sudan.
Betel quid use, for example, leads to submucous fibrosis and is known to result in oral cancer over time. These tissue changes increase with years of use, causing stricture of the oral tissues and progressively decreasing the quality of life for the patient. Patients with submucous fibrosis are also difficult to assess for oral cancer due to limited mouth opening.
A recent study by Babiker, et al. (2017) calls attention to the fact that awareness of the risk factors and identifying the early signs of oral cancer are crucial for dentists and dental hygienists to know. The mortality of the patient and burden on the health-care system may be reduced with early intervention.
We may see patients who come to the United States from areas such as Sudan who have a history of toombak use, and this may go unrecognized. Without the correct knowledge of the product - that is particularly unfamiliar to western health-care providers - the changes in tissues may be disregarded. Some individuals may present with precancerous lesions, early cancer, or late stage disease during a visit to a private dental practice or dental school. Babiker, et al. presents a case for increasing our knowledge of the ramifications of such products on the oral tissues and early identification of tissue changes that early cases may still be effectively treated with reduced morbidity (see Figure 1).
Oral cancer in Sudan, for example, is ranked as the sixth leading cancer among all cancers. The primary cause of its high incidence is due to the use of toombak. This product is made from the finely ground leaves of the Nicotiana rustica plant. It is further mixed with “atron” (sodium bicarbonate) and water in a 4:1 combination to make it alkaline and moist (see Figure 2). Increased alkalinity (11-11.8 ph.) causes fast nicotine absorption in the body and central nervous system.
This type of nicotine is highly addictive due to its easy absorption and causes blood concentration of tobacco to rapidly spike. Another disadvantage of toombak is the high presence of the TSNAs (tobacco specific nitrose amines), which are a potent class of carcinogens. These are found in some of the highest concentrations in the world within toombak, in comparison to other forms of tobacco worldwide.
In the local communities of Sudan, toombak is also called “saffa.” This is rolled up into a medium sized ball and usually placed in the anterior vestibule for two to three hours after which it is discarded and replaced (see Figures 3, 4). Toombak is a homemade product that is not quality regulated by the government of Sudan. Easy access and cheap sales of the product make it readily available for sale and personal use. Usage is widespread amongs all age groups (beginning as young as 10 years old) in both males and females. The product is placed in large containers that may be stored for an unlimited time and quite susceptible to other environmental contaminants. Raised temperatures lead to progressing fermentation, thus compounding its carcinogenic affect.
Toombak users are more susceptible to infections, inflammation of the oral tissues as well as premalignant lesions (dysplasia, keratinization, and hyperkeratosis). It is scientifically proven that toombak lesions display increased dyskeratosis, apoptosis is inhibited, and genetically the P53 tumour suppressor gene is downregulated. Thus, the development of lesions are much more likely to have an invasive nature with the ability to metastasize.
According to Ahmed (2013), four types of tobacco products are consumed. Loose leaf or chewing tobacco, snuff, plug tobacco, and twist or roll tobacco. Chewing tobacco and snuff are reported to be the most widely used. The most favored is toombak is placed in the cheek or lower lip area.
It is also known in Sudan that toombak is associated/implicated with cancers of the nasal cavity, esophagus, pancreas, kidney, and urinary bladder cancers. However, the use of the product is still widely continued, observable in oral cancer rates overall in Sudan. Its damage being seen in the United States amongst Sudanese users of toombak.
Because of cultural norms in Sudan, women do not admit to Toombak use; however, recent studies suggest increasing numbers of female users.
We continue to see many individuals from all corners of the world and increasing our own knowledge in the possibilities and intricacies of oral cancer assist us in our own repertoire of possibilities. It may be wise to include questions of toombak use in dental practices for Sudanese patients.
As always, keep asking good questions and always listen to your patients.
Author’s note: The author would like to thank Dr. Amel Sami for her contribution to this article. She is an oral medicine specialist in Sudan. RDH
1. Ahmed HG. (2013). Etiology of Oral Cancer in the Sudan. Journal of Oral & Maxillofacial Research, 4(2), e3. http://doi.org/10.5037/jomr.2013.4203.
2. Babiker TM, Osman KAA, Mohamed SA, Mohamed MA, Almahdi HM. Oral cancer awareness among dental patients in Omdurman, Sudan: a cross sectional study. BMC Oral Health:2017: 17:69.
NANCY W. BURKHART, BSDH, EdD, is an adjunct associate professor in the department of periodontics/stomatology, Baylor College of Dentistry and the Texas A & M Health Science Center, Dallas. Dr. Burkhart is founder and cohost of the International Oral Lichen Planus Support Group (dentistry.tamhsc.edu/olp/webcasts.html) and coauthor of General and Oral Pathology for the Dental Hygienist. She was awarded a 2016 American Academy of Oral Medicine Affiliate Fellowship (AAOMAF). She was a 2006 Crest/ADHA award winner. She is a 2012 Mentor of Distinction through Philips Oral Healthcare and PennWell Corp. She can be contacted at [email protected].