ORIGINAL�ARTICLE

ABSTRACT
Objective:	The	aim	of	this	study	was	to	test	the	association	between	recurrent	aphthous	ulcers	and	different	
forms	of	tobacco	habits.
Study	Design:	Hospital	based	cross-sectional	study.
Place	and	Duration	of	Study:	The	study	population	consisted	of	patients	attending	the	Out	Patient	Department	
of	Islamic	International	Dental	Hospital	Islamabad.	A	hospital	based	study	is	carried	out	for	2	successive	months	
(July-August)	2018.
Materials	and	Methods:	Study	was	conducted	on	500	patients	to	assess	the	presence	of	aphthous	ulcers.	
Questionnaire	based	data	was	collected	along	with	the	clinical	examination.	 	Questionnaire	included	both	
quantitative	and	qualitative	variables.	Quantitative	variables;	Age,	Frequency	of	addictive	habits,	Duration	of	
addiction,	Size	of	ulcer,	No.	of	lesions,	Duration	of	ulcer	and	Qualitative	variables;	All	types	of	Addictive	habits	
(smoking	and	smokeless	tobacco),	Medical	history,	Frequency	of	recurrence	of	ulcers,	Site	of	ulceration,	Type	of	
aphthous	ulcers.	Statistical	analysis	was	carried	out	using	SPSS	software	version	23	and	chi-squared	test	was	
applied.
Results:	Out	of	500	subjects,	33	(6.6%)	participants	presented	with	aphthous	ulcers.	78	subjects	had	addictive	
habits	of	smoking	tobacco.	Among	them,	Cigarette	Smokers	were	75	(15%),	Hookah	Smokers	were	2	(0.4%)	and	
1	was	a	Bidi	Smoker	(0.2%).	23	subjects	had	addictive	habits	of	using	smokeless	tobacco.	Among	which,	Paan	
Chewers	were	7	(1.4%),	Gutka	Chewers	were	3	(0.6%)	and	13	were	Naswar	Chewers	(2.6%).	
Conclusion:	Although	no	significant	association	has	been	found	between	aphthous	ulcers	and	smoking	habits	
but	ulcers	were	found	to	be	lower	in	patients	who	are	smokers	as	compared	to	the	non-smokers.

Key	Words:	Stomatitis, Aphthous Ulcer, Tobacco Smoking, Smokeless.

that	they	are	painful	and	recurrent	mucosal	lesions	
causing	 discomfort	 while	 eating,	 drinking	 and	
speaking.
There	 are	 three	 clinical	 variations	 of	 aphthous	
stomatitis;
· Minor	aphthous	ulceration
· Major	aphthous	ulceration
· Herpetiform	aphthous	ulceration	
Exact	etiology	of	RAS	is	unknown	but	the	condition	is	
associated	 with	 multiple	 factors	 including	
autoimmunity,	genetic	predispositions,	hematologic	
abnormalities	(anemia),	HIV,	hormonal	fluctuations,	
arthritis,	 stress/anxiety,	 nutritional	 deficiencies,	
trauma,	 drugs,	 food	 hypersensitivity,	 smoking	

1,	3,5,7
cessation	and	allergies.
RAS	 is	 associated	 with	 human	 leukocyte	 antigen	
(HLA)	and	immune-dysregulation.	Lymphocytes	are	
the	predominant	cells	in	pathogenesis	of	RAS	with	a	
variation	 in	 CD4:CD8	 ratio	 during	 pre-ulceration,	

4,5
ulceration,	 and	 healing	 stage.	 	 Tobacco	 reduces	
immunity	and	T	cell	response	to	various	antigens	so	
that	 the	 association	 appears	 to	 be	 biologically	

8
plausible.	 	

Aphthous	ulcer	is	a	common	condition,	also	known	
as	“canker	sores”	or	“aphthous	stomatitis”.	The	term	
aphthae	is	derived	from	Greek	word	“Aphthi”	which	

1,2
means	 “to	 set	 on	 fire”	 or	 “to	 inflame”. 	 It	 is	
characterized	by	the	repeated	formation	of	benign	
and	non-contagious	ulceration	of	the	oral	mucous	

3
membrane. 	 The	 ulcers	 present	 as	 lesions	 having	
yellow	ulcerated	base	surrounded	by	erythematous	

4,5
halos	and	covered	by	fibrino-purulent	membrane. 	
6
Morbidity	 of	 Recurrent	 Aphthous	 Ulcer	 (RAS)	 is	
quite	high	affecting	quality	of	life	of	patients	in	a	way	

Incidence	of	Aphthous	Ulcers	in	All	Forms	of	Tobacco	Users,	Mixed	Habits
and	Non-Users
Rabia	Masood,	Hadia	Malik,	Laiba	Gul,	Zarmeena	Imtiaz,	Ume	Hani	Sajjad

Correspondence:
Dr. Rabia Masood
Assistant Professor
Department of Oral Pathology
Islamic International Dental College
Riphah International University, Islamabad
E-mail:	drrabiamasood@gmail.com

Department of Oral Pathology
Islamic International Dental College
Riphah International University, Islamabad

Funding Source: NIL; Conflict of Interest: NIL
Received: June 10, 2019; Revised: August 27, 2019
Accepted: October 31, 2019

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116



The	 management	 of	 patients	 with	 RAS	 comprises	
application	 of	 topical	 analgesics,	 corticosteroids,	
antibiotics	and	anti-inflammatory	agents	that	only	

1	3
provide	symptomatic	relief.
There	are	different	types	of	tobacco	being	used	in	
Pakistan	 which	 includes	 smoking tobacco	 i.e.	
cigarettes,	cigar,	pipe,	hookah,	shisha	and	bidi	and	
smokeless tobacco	include	paan,	gutka,	naswar,	oral	
snuff,	snuss	(moist	snuff),	khaini	(tobacco	and	lime)	
and	lozenges.
Although	 studies	 have	 failed	 to	 find	 the	 exact	
etiology	 of	 Recurrent	 Aphthous	 Stomatitis	 but	
tobacco	use	is	the	one	most	debatable	and	confused	
anticipated	 factor	 as	 tobacco	 usage	 is	 associated	
with	various	oral	pathologies	such	as	Oral	squamous	
cell	 carcinoma,	 periodontitis,	 gingivitis,	 tobacco	
pouch	 keratosis,	 oral	 sub	 mucous	 fibrosis	 and	
nicotine	 stomatitis	 etc.,	 so	 tobacco	 usage	 should	
logically	lead	to	occurrence	of	Recurrent	Aphthous	
Stomatitis.	However,	in	contrast	to	this	a	number	of	
studies	 have	 shown	 negative	 correlation	 between	
RAS	 and	 tobacco	 usage	 and	 positive	 therapeutic	

3
effects	of	smoking.	 	Tobacco	usage	causes	thickening	
(keratinization)	 of	 oral	 mucosa	 which	 renders	 the	

4	 5
mucosa	less	susceptible	to	ulceration.	 	 	Smokers	
quitting	 with	 nicotine	 chewing	 gums	 have	 less	
chances	 to	 develop	 ulcers	 than	 those	 without	

9
nicotine	replacement	therapy.	
Previous	 studies	 have	 suggested	 negative	
association	 between	 tobacco	 usage	 and	 RAU	 but	
most	of	those	studies	assessed	relationship	between	
RAS	and	tobacco	by	using	methods	that	were	based	
on	interviews,	questionnaire,	or	on	self-reporting	of	

3	,10	,11
smoking	status. 	
However,	the	studies	that	were	previously	carried	
out	did	not	evaluate	occurrence	of	aphthous	ulcers	in	
different	forms	of	tobacco	users,	mixed	habits	and	
non-users.	In	our	study	we	wanted	to	evaluate	the	
strength	 of	 association	 between	 occurrence	 of	
aphthous	ulcer	and	tobacco	usage	and	incidence	of	
aphthous	 ulcer	 among	 different	 types	 of	 tobacco	
users	in	our	population	and	comparing	them	with	
non-users	because	no	such	study	has	been	done	in	
our	community.
The	 objective	 of	 this	 study	 was	 to	 assess	 the	
association	between	recurrent	aphthous	ulcers	and	
different	forms	of	tobacco	habits.	
Materials	and	Methods
Hospital	based	cross-sectional	study	design	was	used	
to	assess	the	incidence	of	aphthous	ulcers	in	tobacco	

users,	non-users	and	those	with	mixed	habits.
The	study	population	consisted	of	patients	attending	
the	Out	Patient	Department	of	Islamic	International	
Dental	Hospital	Islamabad.	A	hospital	based	study	
was	 carried	 out	 for	 2	 successive	 months	 (July-
August)	2018.	Study	was	conducted	on	500	patients	
who	visited	OPD	of	dental	hospital	for	seeking	dental	
treatment.	 All	 subjects	 were	 interviewed	 and	 a	
structured	questionnaire	was	developed	to	record	
their	details.	The	questionnaire	contained	four	main	
sections	 (addictive	 habits/tobacco	 usage	 history,	
aphthous	 ulcer	 related	 medical	 history,	 ulcer	
characteristics	 and	 demographics).	 The	 Addictive 
habits section	had	two	domains;	Smoking	tobacco	
domain	 comprised	 of	 six	 tobacco	 usage	 habits	
(smoking	cigarettes,	cigar,	hookah,	pipe,	shisha,	bidi)	
and	Smokeless	tobacco	domain	also	had	six	habits	
(paan,	ghutka,	naswar,	snuff,	lozenges,	other	habits).	
Medical history	associated	with	the	occurrence	of	
aphthous	 ulcers	 included	 Anemia,	 HIV,	 Hormonal	
fluctuations,	 GI	 disorders,	 Arthritis,	 Stress/anxiety,	
Allergies	 and	 genetic	 predisposition.	 Ulcer 
characteristics	 comprised	 size	 of	 ulcer,	 number	 of	
lesions,	site	of	ulceration,	frequency	of	recurrence	
and	duration	of	ulcers.
Informed	Consent	was	taken	from	all	the	participants	
before	conducting	the	study.	The	participants	were	
asked	whether	they	had	oral	ulcers	(aphthous	ulcers)	
present	in	their	mouth	after	describing	aphthosis	to	
them	 as	 recurrent	 painful	 ulcers.	 Additional	
information	about	ulcers	like	duration,	location,	size,	
recurrence,	and	no.	of	ulcers	was	noted.	Moreover,	
risk	factors	that	might	be	related	to	condition	were	
inquired	 (stress,	 hormonal	 factors,	 GD	 disorders,	
allergies).
Participants	 were	 classified	 into	 3	 groups	 and	 the	
selection	criteria	for	the	groups	are	given	below:
Control	Group:
Inclusion criteria	 included	 male	 and	 female	 of	 15	
years	and	above,	subjecting	without	any	ulcers	and	
without	any	addictive	habits.							
Exclusion criteria included patients	under	15	years,	
subjecting	with	ulcers	and	with	addictive	habits
Smokers	group:
	Inclusion	criteria included	male	and	female	patients	
of	 15	 years	 and	 above,	 subjecting	 with	 smoking	
habits	(Cigarette,	cigar,	pipe,	hookah,	shisha,	bidi)	
and	with/without	ulcers.
Exclusion criteria included patients	 under	 15	 year	

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subjecting	without	any	smoking	habits.
Non-smokers	group:
Inclusion criteria	included	male	and	female	patients	
of	 15	 years	 and	 above,	 Subjecting	 without	 any	
smoking	 habits,	 with	 smokeless	 tobacco	 habits	
(paan,	 gutka,	 naswar,	 snuff,	 lozenges)	 and	
with/without	ulcers.
Exclusion	 criteria	 included patients	 less	 than	 15	
years, subjecting	with	smoking	habits and	without	
any	smokeless	tobacco	habits.
To	 assess	 the	 presence	 of	 aphthous	 ulcers,	 oral	
mucosal	 examination	 and	 questionnaire	 were	
completed	 for	 500	 patients	 reporting	 to	 the	 OPD	
over	a	2-month	interval	by	four	examiners.	History	of	
addictive	habits	was	taken	and	tobacco	usage	was	
measured	 on	 the	 basis	 of	 type	 of	 tobacco	 used,	
frequency	of	consumption	per	day	and	the	duration	
for	which	the	individual	maintained	this	frequency.	
To	avoid	confounding,	patients	with	known	history	of	
systemic	diseases	and	other	conditions	that	might	
influence	 occurrence	 of	 aphthous	 ulcer	 were	 also	
recorded.	 And	 finally	 on	 the	 basis	 of	 ulcer	
characteristics,	 aphthous	 ulcerations	 were	
categorized	 into	 minor,	 major	 and	 herpetiform	
ulcers.
Both	quantitative	and	qualitative	variables	were	part	
of	this	study.	
Quantitative	variables;	age,	frequency	of	addictive	
habits,	 duration	 of	 addiction,	 size	 of	 ulcer,	 no.	 of	
lesions,	and	duration	of	ulcer.
Qualitative	 variables;	 All	 types	 of	 Addictive	 habits	
(smoking	and	smokeless	tobacco),	Medical	history,	
Frequency	of	recurrence	of	ulcers,	Site	of	ulceration	
and	types	of	aphthous	ulcers.	
Statistical	 analysis	 was	 carried	 out	 using	 SPSS	
software	version	23.	Frequency	and	percentages	of	
different	variables	were	calculated	using	SPSS	and	
formulated	in	tables	1,	2,	and	3.

Results
All	 500	 subjects	 were	 asked	 about	 their	 medical	
histories.	 Out	 of	 500,	 only	 5	 subjects	 (1%)	 were	
anemic.	 10	 subjects	 (2%)	 had	 hormonal	 disorders	
related	 with	 puberty,	 menstrual	 cycle	 and	
pregnancy,	 83	 subjects	 (16.6%)	 had	 GI	 disorders	
related	to	acidity,	7	subjects	(1.4%)	had	arthritis,	74	
subjects	 (14.8)	 experienced	 stress	 related	
ulcerations	during	exams	or	social	issues.	61	subjects	
(12.2%)	 were	 allergic	 to	 dust,	 pollen	 and	

medications,	 and	 5	 subjects	 (1%)	 presented	 with	
family	history	of	recurrent	ulcers.	

Table	I:	Self-Reported	Medical	History	of	Pa�ents

Out	of	500	subjects,	78	subjects	had	addictive	habits	
of	 smoking	 tobacco.	 Among	 those	 78,	 Cigarette 
Smokers	 were	 75	 (15%),	 Hookah Smokers	 were	 2	
(0.4%)	and	1	was	a	 Bidi Smoker	(0.2%).	(Graph	1).	
From	500	subjects,	23	subjects	had	addictive	habits	
of	using	smokeless	tobacco.	And	of	those	23,	Paan 
Chewers	were	7	(1.4%),	Gutka Chewers	were	3	(0.6%)	
and	 13	 were	 Naswar Chewers	 (2.6%).	 (Graph	 2).	
From	a	group	of	101	subjects	that	presented	with	
addictive	 habits	 of	 either	 smoking	 or	 smokeless	
tobacco	46	were	addicted	for	more	than	a	period	of	7	
years.	Table-II	illustrates	distribution	of	duration	of	
addiction	among	addicts:
Table	II:	Dura�on	of	Tobacco	Addic�on

33	 (6.6%)	 participants	 presented	 with	 aphthous	
ulcers.	Pertaining	to	the	ulcer	characteristics	given	in	
Table	III,	2	patients	presented	with	Major	Aphthous	
Ulceration	 and	 31	 patients	 presented	 with	 Minor	
Aphthous	 Ulcerations.	 None	 of	 the	 patients	
presented	with	Herpetiform	Aphthous	Ulcerations	
during	the	period	of	sample	collection.	And	out	of	
these	 33	 subjects	 who	 presented	 with	 aphthous	
ulcers,	5	were	cigarette	smokers	while	remaining	28	
had	no	history	of	any	addictive	habits	(smoking	or	
smokeless	tobacco).
Presence	 of	 aphthous	 ulcers	 was	 correlated	 with	
self-reported	 medical	 conditions;	 5	 out	 of	 33	
subjects	 (15.1%)	 were	 allergic,	 9	 (27.2%)	 had	 GI	
disorders,	3	(9%)	had	hormonal	disorders,	12	(36.4%)	
had	 stress-related	 ulcers,	 4	 (12.1%)	 had	 genetic	
association	 and	 6	 (18.2%)	 subjects	 presented	
without	any	significant	medical	history.	Occurrence	
of	RAU	is	affected	by	a	number	of	other	variables,	
with	no	statistically	significant	influence	of	tobacco	
usage.

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Incidence	of	RAU	in	tobacco	users	and	non-users	was	
statistically	 analyzed	 by	 using	 Chi-squared	 test.	
Cigarette	 smoking	 was	 considered	 to	 represent	
tobacco	usage	as	significant	number	of	tobacco	users	
were	cigarette	smokers	as	compared	with	negligible	
amount	 of	 other	 tobacco	 variables.	 Cigarette	
smoking	was	compared	with	presence	of	RAU	and	
type	of	ulcers	if	present.	Statistical	analysis	of	our	
study	showed	no	significant	association	between	the	
presence	of	aphthous	ulcers	and	cigarette	smoking	
(p	value	=	0.98)	and	between	cigarette	smoking	and	
type	of	aphthous	ulcers	(p	value	=	0.72)	as	shown	in	
the	Table	IV	and	Table	V.	

genetic	factors,	hormonal	factors,	stress,	infections,	
GI	disorders	etc.	No	randomized	control	trial	have	
shown	any	treatment,	that	could	help	in	preventing	

4
or	curing	RAU. 	
RELATIONSHIP	 BETWEEN	 TOBACCO	 HABITS	 AND	
RAU:	An	inverse	relationship	is	observed	between	
RAU	 frequency	 and	 smoking	 habits	 according	 to	

3,5,9
previous	 studies	 held. 	 The	 observations	
previously	 made	 by	 Tony	 Axell	 and	 Vingent	
Henricsson	 also	 presents	 that	 there	 is	 a	 negative	
association	 between	 tobacco	 habits	 and	 RAU.	 	
According	 to	 them,	 surface	 structures	 like	
leukoedema	and	keratin	prevent	the	penetration	of	

9
antigenic	 substances	 into	 the	 oral	 epithelium. 	
Shapiro	et	al.	found	that	there	is	a	negative	relation	
between	 RAU	 and	 smoking.	 They	 pointed	 that	
genetic,	 familial,	 psychological	 and	 environmental	
factors	 are	 important	 considerations	 in	 the	
formation	 of	 recurrent	 aphthous	 ulceration.	 They	
suggest	 that	 meaningful	 data	 can	 be	 obtained	 by	
multidisciplinary	longitudinal	studies.	According	to	
Banoczy	and	Sallay	there	is	a	negative	association	
between	 keratinization	 of	 oral	 mucosa	 and	

12
aphthae. 	 The	 findings	 of	 the	 case	 control	 study	
given	by	PA	Atkin,	X	Xu,	and	MH	Thornhill	indicate	
that	patients	with	RAU	have	low	levels	of	smoking	
than	 in	 matched	 controls,	 and	 they	 support	 that	
there	is	a	negative	correlation	between	minor	RAU	

4
and	smoking. 	The	negative	correlation	of	smokeless	
tobacco		with	recurrent	aphthous	stomatitis	is	also	

3
given	in	a	study	by	Grady	et	al.	 The	case	control	study	
given	 by	 Shamaz	 Mohamed	 and	 Chandrashekar	
Janakiram	found	the	statistical	association	between	
the	 RAU	 and	 usage	 of	 tobacco	 smoking.	 The	
association	 that	 exists	 between	 smoking	 and	
aphthous	mouth	ulcers	is	negative.	The	non-	tobacco	
users	tend	to	have	55%	more	chance	of	occurrence	

1
of	RAU	than	tobacco	users. 	
However,	 study	 carried	 out	 by	 Slebioda	 Z	 and	
Dorocka,	showed	there	is	no	significant	association	
found	 between	 smoking	 tobacco	 habits	 and	

13
occurrence	of	Recurrent	Aphthous	ulcers.
Protective	Effect	of	Smoking
Epidemiological	studies	suggest	a	protective	effect	of	
smoking.	These	studies	show	that	mouth	ulcers	are	

4,14,15
more	common	in	nonsmokers	than	in	smokers. 	
The	 reason	 that	 might	 be	 associated	 with	 this	
protective	effect	of	tobacco	use	could	be	increased	

3
keratinization	of	oral	mucous	membrane	 	or	some	
substances	 present	 in	 cigarette	 smoke	 absorbed	

Table	III:		Ulcer	Characteris�cs

Table	IV:	Rela�onship	of	Cigare�e	Smoking	with	
Aphthous	Ulcer

TABLE	V:	Incidence	of	Aphthous	Ulcer	among	Smokers

and	Non-Smokers

Discussion
Aphthous	ulcers	are	recurrent	and	painful	condition	

3
of	oral	mucosa,	etiology	of	which	is	still	unknown. 	
There	are	certain	risk	factors	that	are	associated	with	
occurrence	 of	 RAU	 including	 immune	 reaction,	

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Le

Re

Ul

Le

Ch

I



causing	decrease	in	frequency	of	RAU.	Case	studies	
suggest	that	the	nicotine	chewing	gums	are	helpful	

16
for	the	nonsmokers	who	have	mouth	ulcers. 	Most	
of	the	population,	on	cessation	of	smoking	appear	to	
develop	RAU	for	the	first	time	or	any	previous	RAU	

4,17
that	existed,	has	exacerbated. 	This	might	possibly	
be	due	to	increased	keratinization	of	oral	mucosa,	

17,18
antibacterial	effect	of	tobacco	smoke 	or	smoking	
cessation	have	effects	on	immune	system	like	stress	

17
generated	due	to	withdrawal. 	
Comparison	with	Literature:	Most	of	these	previous	
studies	 assessed	 relationship	 between	 RAU	 and	
tobacco	 by	 using	 methods	 that	 were	 based	 on	
interviews,	 questionnaires,	 or	 on	 self-reporting	 of	

3,10,11
smoking	status.
Our	 study	 also	 used	 the	 same	 method	 as	 special	
questionnaire	 was	 designed	 according	 to	 which	
significantly	smaller	population	of	RAU	patients	were	
smokers	(15%)	as	compared	to	control	group	who	
were	 nonsmokers	 (84.4%)	 in	 a	 sample	 of	 500	
patients.	Most	of	the	incidences	of	RAU	were	found	
among	sample	population	who	were	non	tobacco	
users.	 Some	 daily	 tobacco	 habits	 were	 found	 in	
patients	among	which	smoking	was	most	common	
habit	especially	cigarette	smoking	while	some	in	rest	
of	 the	 sample	 were	 addicted	 to	 other	 forms	 of	
tobacco	(smoking	and	smokeless)	and	no	ulcers	were	

1	3	5	15
found	among	them.	In	contrast	to	other	studies	 	
our	study	showed	no	significant	association	between	
presence	 of	 ulcers	 and	 cigarette	 smoking	 and	 no	
association	between	cigarette	smoking	and	type	of	
ulcers.	
Limitations	and	Future	Recommendations
The	factors	that	might	have	affected	our	results	could	
be	 that	 these	 lesion	 are	 not	 fixed	 long	 standing	
lesions,	that	can	 be	evaluated	at	any	time	by	the	
physician	 ,	 but	 are	 short	 lived	 that	 may	 not	 be	

15
present	 at	 the	 time	 of	 examination 	 statistical	
evaluation	of	RAU	might	have	been	affected	by	this	
fact.	In	addition,	the	methods	of	assessing	smoking	
status	could	be	inaccurate	as	smokers	may	hide	their	
smoking	 status	 or	 underestimate	 their	 level	 of	
smoking.	Our	study	was	unable	to	show	incidence	of	
aphthous	ulcers	between	different	genders	and	the	
medical	conditions	that	might	affect	the	occurrence	
of	aphthous	ulcers	in	our	community,	so	in	future	we	
would	suggest	that	further	studies	be	carried	out	on	
these	aspects.
Conclusion
Incidence	of	RAU	in	tobacco	users	and	non-users	has	

been	 assessed	 and	 statistically	 analyzed	 showing	
that	occurrence	of	ulcers	is	lower	in	patients	who	are	
smokers	as	compared	to	non-smokers.	However,	no	
significant	association	has	been	found	between	ulcer	
occurrence	 and	 smoking	 habits.	 These	 findings	
substantiate	with	the	previous	similar	studies	and	
can	serve	as	a	base	for	further	research	in	future.

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2.	 Edgar	 NR,	 Saleh	 D,	 Miller	 RA.	 Recurrent	 Aphthous	
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3.	 Grady	D,	Ernster	VL,	Stillman	L,	et	al.	Smokeless	tobacco	use	
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