Academic Edi o s: Sil ano D agonie i
and Ja i P. Ahlbe g
Recei ed: 3 July 2025
Accep ed: 11 July 2025
Published: 15 July 2025
Ci a ion: Doblado, N.G.; Ba e a
Mo a, J.M.; Do ado, F.P.; Fe nández,
J.C.R.; O deix, G.B.; Escalona, E.E.
Rela ionship Be ween B uxism and
Obs uc i e Sleep Apnea: A
Sys ema ic Re iew o he Li e a u e. J.
Clin. Med. 2025,14, 5013. h ps://
doi.o g/10.3390/jcm14145013
Copy igh : © 2025 by he au ho s.
Licensee MDPI, Basel, Swi ze land.
This a icle is an open access a icle
dis ibu ed unde he e ms and
condi ions o he C ea i e Commons
A ibu ion (CC BY) license
(h ps://c ea i ecommons.o g/
licenses/by/4.0/).
Sys ema ic Re iew
Rela ionship Be ween B uxism and Obs uc i e Sleep Apnea:
A Sys ema ic Re iew o he Li e a u e
Na alia Ga cía Doblado 1, José Ma ía Ba e a Mo a 2,* , F ancisco Pas o Do ado 2,
Juan C. Rod íguez Fe nández 2, Guillem Balles e o O deix 3and Edua do Espina Escalona 2
1School o Den is y, Uni e si y o Se illa, 41009 Se illa, Spain; [email p o ec ed]
2O hodon ics Sec ion, Depa men o S oma ology, School o Den is y, Uni e si y o Se illa,
41009 Se illa, Spain; [email p o ec ed] (F.P.D.); [email p o ec ed] (J.C.R.F.); [email p o ec ed] (E.E.E.)
3
School o Den is y, Uni e si y In e na ional o Ca alunya, 08017 Ba celona, Spain; d gballes e [email p o ec ed]
*Co espondence: [email p o ec ed]
Abs ac
Backg ound and objec i es: The in e es in s udying he ela ionship be ween b uxism and
sleep apnea has inc eased o e he pas decade, gi en i s p e alence and i s implica ions o
bo h o al and o e all heal h. B uxism occu s in a signi ican po ion o he popula ion, wi h
an o e all incidence anging be ween 8 and 31%. Obs uc i e sleep apnea a ec s 4–6% o
middle-aged men and 2–4% o middle-aged women, and i is associa ed wi h diminished
quali y o li e, hype ension, inc eased ca dio ascula isks, a ic acciden s, and a highe
mo ali y a e. Al hough a possible associa ion has been sugges ed, he causal ela ionship
emains unclea . This e iew aimed o sys ema ically e alua e he a ailable e idence on he
associa ion be ween SB and OSA, ocusing on po en ial sha ed isk ac o s and unde lying
mechanisms. Me hods: An elec onic li e a u e sea ch was conduc ed in PubMed, Scopus,
Web o Science, and he Coch ane Lib a y o s udies published be ween 2020 and 2025.
Inclusion c i e ia encompassed obse a ional s udies and clinical ials in ol ing adul s
wi h SB and/o OSA. Risk o bias was assessed using ROBINS-I, and he ce ain y o
e idence was e alua ed using GRADE. The e iew p o ocol was no egis e ed. Resul s: A
o al o 11 s udies me he inclusion c i e ia. The p e alence o SB was consis en ly highe
in indi iduals wi h OSA compa ed o he gene al popula ion. Se e al s udies sugges a
po en ial link h ough au onomic a ousals and neu o ansmi e dys egula ion. Howe e ,
inconsis encies in diagnos ic c i e ia and mode a e me hodological quali y limi ed he
s eng h o he indings. Conclusions: The e is a no able p e alence o b uxism in pa ien s
wi h OSA, sugges ing possible sha ed pa hophysiological mechanisms; howe e , i is
necessa y o s anda dize diagnos ic c i e ia and conduc la ge , mo e s anda dized s udies
o cla i y he ela ionship. No unding was ecei ed, and he au ho s decla e no con lic s
o in e es .
Keywo ds: sleep b uxism; obs uc i e sleep apnea; isk ac o s; polysomnog aphy
1. In oduc ion
Sleep b uxism (SB) and obs uc i e sleep apnea (OSA) a e condi ions ha ha e a
subs an ial impac on bo h o al and gene al heal h. The mos widely accep ed de ini ion o
b uxism was o mula ed in 2013 a an in e na ional consensus [1], whe e i was desc ibed
as a “ epe i i e ac i i y o he mandibula muscles cha ac e ized by clenching o g inding
he ee h and/o b acing o h us ing he mandible.” I can occu while awake (awake
J. Clin. Med. 2025,14, 5013 h ps://doi.o g/10.3390/jcm14145013
J. Clin. Med. 2025,14, 5013 2 o 15
b uxism) o du ing sleep (sleep b uxism) [
2
]. Bo h ypes a e ega ded as di e en beha io s,
wi h dis inc de ini ions and mul i ac o ial o igins: biological (neu o ansmi e s, gene ics),
psychological (s ess, anxie y), and exogenous ( obacco, alcohol, d ugs).
Recen s udies es ima e he p e alence o SB o ange be ween 8% and 13% in he gen-
e al adul popula ion, hough sel - epo ed a es may each highe alues when subjec i e
me hods a e used [
1
–
7
]. Meanwhile, OSA a ec s app oxima ely 15% o 30% o men and
10% o 15% o women in middle age, depending on he diagnos ic c i e ia used and he
popula ion s udied [8].
Clinically, b uxism may be ha mless, a isk ac o , o e en a p o ec i e ac o , depend-
ing on he con ex . Fo example, i is hough ha i may p o ec he ai way in pa ien s wi h
OSA o s imula e sali a ion in he p esence o gas o-esophageal e lux; con e sely, i can
also gi e ise o muscula pain, oo h wea , headaches, and damage o o al s uc u es [
2
,
9
].
Du ing sleep, SB mani es s i sel h ough epe i i e hy hmic mas ica o y muscle
con ac ions (RMMA), which may be phasic, onic, o mixed [
3
,
9
–
11
]. Diagnosis is based
on pa ien in e iew, clinical examina ion, in a-o al de ices, elec omyog aphy (EMG), o
polysomnog aphy (PSG), he la e being he gold s anda d owing o i s abili y o eco d
mul iple physiological pa ame e s du ing sleep [12].
OSA is cha ac e ized by epea ed episodes o apnea and hypopnea ha a e caused
by collapse o he uppe ai way, leading o hypoxemia and hype capnia accompanied by
mic o-a ousals and al e a ions in sleep a chi ec u e [
13
,
14
]. OSA is diagnosed when he
apnea–hypopnea index (AHI) is
≥
15 e en s
·
h
−1
, o
≥
5 e en s
·
h
−1
i he e a e symp oms
such as excessi e day ime sleepiness o a igue [15].
The pa hogenesis o OSA is highly he e ogeneous and is in luenced by ana omical
ac o s, impai men o he pha yngeal dila o muscles, en ila o y con ol ins abili y, and a
low a ousal h eshold. Lung olume, luid edis ibu ion, and a ousal in ensi y also play a
ole [
15
–
22
]. The main isk ac o s include male sex, middle age, obesi y, alcohol, obacco,
and sleeping in he supine posi ion [13].
The ypical OSA cycle comp ises apnea–hypopnea, blood-gas al e a ions, mic o-
a ousal, and es o a ion o ai low, which agmen s sleep and causes day ime somnolence,
sno ing, a igue, headaches, and o he symp oms. In se e e cases, pa ien s may expe ience
oad- a ic acciden s and ca dio ascula , neu o-cogni i e, and me abolic consequences [
13
].
The e minology has e ol ed o e ime. A p esen he p e e ed e m is “obs uc i e
sleep apnea” (OSA), omi ing wo ds such as “synd ome” o “hypopnea” o be e e lec
he na u e o he diso de [14].
Despi e p io e o s o cla i y he link be ween sleep b uxism and obs uc i e sleep
apnea, cu en e idence emains inconclusi e. Fo ins ance, he scoping e iew by Paule o
e al. [
16
] ound no consis en associa ion in adul popula ions, la gely due o a iabili y
in s udy designs and diagnos ic app oaches. Likewise, he sys ema ic e iew and me a-
analysis conduc ed by Błaszczyk e al. [
17
] did no ind a s a is ically signi ican ela ionship
be ween he wo condi ions, no ing, howe e , ha he me hodological quali y o he
included s udies was gene ally low. These indings highligh he ongoing need o mo e
cu en and me hodologically obus in es iga ions.
The aim o he p esen s udy was o e alua e he a ailable scien i ic e idence on
he ela ionship be ween sleep b uxism (SB) and obs uc i e sleep apnea (OSA) h ough a
sys ema ic li e a u e e iew. Th ee speci ic objec i es we e se : (1) o analyze he pa hophys-
iological mechanisms ha could explain he ela ionship be ween SB and OSA, assessing
whe he he e is a causal link o me e coexis ence; (2) o examine he ole o isk ac o s in
he de elopmen o b uxism in pa ien s wi h OSA; and (3) o assess he me hodological
quali y o he s udies included.
J. Clin. Med. 2025,14, 5013 3 o 15
Las ly, based on he analysis o he selec ed pape s, a conclusion will be d awn ha
syn hesizes he mos ele an indings.
2. Ma e ials and Me hods
2.1. P o ocol and Regis a ion
This sys ema ic e iew adhe es o he c i e ia laid down in he PRISMA 2020 (P e e ed
Repo ing I ems o Sys ema ic Re iews and Me a-Analyses) s a emen .
The e iew p o ocol was no submi ed o a public egis y owing o ime limi a ions.
2.2. P.I.C.O. Ques ion
The co ne s one o he e iew was he o mula ion o a speci ic, s uc u ed clinical
ques ion using he key concep s ha would guide and acili a e he sea ch o , and e ie al
o , he mos no able and pe inen in o ma ion equi ed o ca y ou his sys ema ic e iew
(Table 1).
Table 1. P.I.C.O. ques ion.
P
(Pa ien )
I
(In e en ion)
C
(Compa ison)
O
(Ou come)
“Sleep B uxism” AND
“Sleep Apnea Synd omes”
“Obse a ion ela ionship”
“Con ol G oups” “Risk ac o s”
2.3. Inclusion and Exclusion C i e ia
To enable an app op ia e selec ion o a icles e ie ed in he a ious sea ches, he
ollowing inclusion and exclusion c i e ia we e es ablished.
2.3.1. Inclusion C i e ia
This e iew included o iginal esea ch a icles ha me he ollowing condi ions: (A)
s udies conduc ed in human popula ions, including p ospec i e o e ospec i e designs,
andomized clinical ials, obse a ional s udies, and case–con ol s udies; (B) only a icles
published be ween 2020 and 2025 we e included o ensu e he ele ance o he da a and
manage he high olume o publica ions a ailable on he opic, hus a oiding excessi e he -
e ogenei y in s udy design and diagnos ic c i e ia; (C) s udies in ol ing pa ien s diagnosed
wi h b uxism, obs uc i e sleep apnea, o bo h; (D) publica ions explici ly add essing he
ela ionship be ween b uxism and sleep apnea; and (E) s udies p o iding ele an da a o
indings ha con ibu e o he objec i es o his e iew.
2.3.2. Exclusion C i e ia
We excluded s udies based on he ollowing c i e ia: (A) esea ch conduc ed in non-
human models o pedia ic popula ions; (B) publica ion ypes such as le e s, au ho
esponses, edi o ials, case epo s, case se ies, pilo s udies, me a-analyses, and o he
sys ema ic e iews; (C) duplica e a icles iden i ied ac oss da abases o a oid edundan
da a; (D) s udies wi h poo ly desc ibed me hodologies o insu icien de ail o e alua ion;
and (E) a icles whose con en was no di ec ly ela ed o he ocus o his sys ema ic e iew.
No language es ic ions we e imposed.
2.4. In o ma ion Sou ces and Sea ch S a egy
To iden i y he s udies included in ou wo k, se e al bibliog aphical sea ches we e
pe o med in he main scien i ic da abases: PubMed, Scopus, he Coch ane Lib a y, and
Web o Science.
J. Clin. Med. 2025,14, 5013 4 o 15
The ollowing sea ch s a egies we e designed, using con olled ocabula y e ms
aligned wi h he opic o he e iew and combined s a egically wi h Boolean ope a o s:
The e ms “B uxism” OR “Sleep B uxism” we e combined wi h “Risk Fac o s” OR
“Occlusal isk ac o s” o iden i y s udies ocusing on possible con ibu ing elemen s.
A b oade sea ch linked “B uxism” OR “Sleep B uxism” wi h “Sleep Apnea Syn-
d omes” OR “Obs uc i e Sleep Apnea” and “Risk Fac o s” OR “Occlusal isk ac o s”, o
explo e sha ed o o e lapping isk p o iles.
To cap u e s udies add essing coexis ing condi ions, he e ms “B uxism” OR “Sleep
B uxism” we e pai ed wi h “Obs uc i e Sleep Apnea” and “Como bidi y.”
Addi ionally, sea ches combined “B uxism” OR “Sleep B uxism” wi h he e m “Co-
mo bidi y” o de ec b oade associa ions.
Finally, we used he combina ion “B uxism” OR “Sleep B uxism” wi h “Obs uc i e
Sleep Apnea” and “Rela ionship” o iden i y s udies di ec ly analyzing he in e ac ion
be ween he wo condi ions.
All e ie ed esul s we e expo ed o Zo e o o managemen , and duplica es we e
sys ema ically emo ed p io o sc eening.
The ull me hodological de ails can be ound in Supplemen a y Table S1, included in
he Supplemen a y Ma e ial File.
2.5. S udy Selec ion and Da a Ex ac ion P ocess
The ini ial sc eening o i les and abs ac s was pe o med independen ly by wo
e iewe s, who applied he p ede ined inclusion and exclusion c i e ia. Disag eemen s
du ing his phase we e discussed un il a consensus was eached. Subsequen ly, he ull ex s
o po en ially eligible a icles we e assessed independen ly by he same e iewe s o con i m
hei ele ance. Any disc epancies we e esol ed h ough join e iew and consensus.
2.6. Da a Cha ing and Le el o E idence
Fo each s udy included in his sys ema ic e iew, he ollowing da a we e collec ed:
i le and au ho , jou nal and yea o publica ion, s udy design and le el o e idence,
pu pose o he esea ch, ma e ials and me hods used, as well as sample size, mean age, and
main conclusions.
To de e mine he le el o e idence o he analyzed a icles, we used he classi ica ion
es ablished by he Ox o d Cen e o E idence-Based Medicine (OCEBM). The GRADE
sys em was also used o assess he ce ain y o he e idence.
2.7. Risk o Bias in Indi idual S udies
To assess he quali y o he in o ma ion con ained in he s udies, we employed he
ROBINS-I (Risk o Bias in Non-Randomized S udies o In e en ions) ool, designed o
e alua e he isk o bias in obse a ional s udies (see Supplemen a y Table S2 o de ailed
assessmen .).
2.8. Risk o Bias Ac oss he Included S udies—Ce ain y o E idence Assessmen
The GRADE (G ading o Recommenda ions, Assessmen , De elopmen , and E alua-
ions) ool was applied o assess he associa ed ce ain y o e idence.
3. Resul s
3.1. S udy Selec ion
Figu e 1shows he PRISMA low diag am, which clea ly, s uc u ally, and concisely
depic s he s udy-selec ion p ocess.
J. Clin. Med. 2025,14, 5013 5 o 15
Figu e 1. Final low diag am.
The ini ial sea ch o se e al da abases yielded 704 esul s, which we e expo ed o
Zo e o e e ence manage ( e sion 7.0.15, 64-bi ). A e emo ing 287 duplica e eco ds,
417 a icles emained. O hese, 337 we e excluded a e i le sc eening and 47 a e e-
iewing he abs ac , as hey did no mee he inclusion–exclusion c i e ia o p o ided
in o ma ion ha was no ele an o he e iew. A his s age, 35 ull- ex a icles emained
o eligibili y assessmen .
J. Clin. Med. 2025,14, 5013 6 o 15
Finally, 5 a icles we e excluded owing o lack o access, 7 because o ques ionable
me hodology, 2 because o sample cha ac e is ics and 9 o no con aining signi ican
in o ma ion, esul ing in a o al o 11 a icles included in he e iew. Only one e iewe
conduc ed he s udy selec ion p ocess.
3.2. S udy Cha ac e is ics
O he ele en a icles included, one [
23
] was a p ospec i e clinical ial and en we e
obse a ional s udies [
24
–
33
]. O hese la e s udies, i e a e
c oss-sec ional [26–28,30,31]
,
h ee a e case–con ol [
25
,
32
,
33
], and wo a e coho s udies [
24
,
29
]. All a e w i en
in English.
Eigh o he s udies analyze he ela ionship be ween b uxism and sleep
apnea [26–33],
and some o hem e en explo e hese condi ions oge he wi h alcohol consump ion,
an idep essan he apy, o insomnia synd ome. Two o he s compa e he e ec o ea men
wi h MAD [
23
] and PAP [
24
] pa ien s wi h b uxism and apnea, and he emaining a icle
assesses sleep-a chi ec u e condi ions in pa ien s wi h b uxism [25].
Table 2summa izes he ele an in o ma ion om each o he included s udies, de ail-
ing he i le, au ho s, jou nal and yea o publica ion, s udy ype, le el o e idence, objec i e,
ma e ials and me hods used, sample size, and mean age, as well as he main conclusions.
Table 2. Summa y o he selec ed s udies.
Ti le/Au ho Jou nal/Yea S udy Type Le el o
E idence Objec i e
Ma e ials and Me hods
Conclusions
The e ec s o
mandibula
ad ancemen appliance
he apy on jaw-closing
muscle ac i i y du ing
sleep in pa ien s wi h
obs uc i e sleep apnea:
a 3–6 mon hs ollow-up
(Aa ab e al.) [23]
Jou nal o
Clinical Sleep
Medicine,
(2020)
Randomized
con olled
ial 1b
To in es iga e he
e ec s o MAD
he apy on
jaw-closing muscle
ac i i y (JCMA)
ela ed o
espi a o y a ousals
in OSA.
18 pa ien s (5 women,
13 men) wi h OSA; wo
PSG eco dings (wi h
and wi hou MAD).
Mean age
49.4 ±9.8 yea s.
MAD he apy
signi ican ly
educed
mandibula muscle
ac i i y associa ed
wi h espi a o y
a ousals in pa ien s
wi h OSA.
P e alence and
p edic o s o sleep
b uxism in pa ien s
wi h obs uc i e sleep
apnea and he e ec o
posi i e ai way
p essu e ea men
(Dadphan e al.) [24]
Sleep and
B ea hing
(2024) Coho S udy 3b
To de e mine he
p e alence and isk
ac o s o SB in
pa ien s wi h OSA
and o compa e SB
episodes be o e and
du ing posi i e
ai way p essu e
(PAP) he apy.
Re ospec i e e iew o
100 OSA pa ien s
(73 men, 27 women)
who unde wen
spli -nigh PSG and
op imal PAP.
SB g oup: 49 pa ien s
(33 men and 16 women)
Non-SB g oup:
51 pa ien s (40 men and
11 women)
Mean age:
50.8 ±16.7 yea s
Abou 49% o
pa ien s had SB,
mos ly associa ed
wi h OSA; op imal
PAP signi ican ly
educed SB
episodes.
Sleep a chi ec u e and
ac o s associa ed wi h
sleep b uxism diagnosis
sco ed by
polysomnog aphy
eco dings: A
case-con ol s udy
(Holanda e al.) [25]
A chi es o
O al Biology,
(2020)
Case–con ol
S udy 3b
To assess he
associa ion be ween
sleep a chi ec u e,
clinical condi ions
and SB diagnosis
using PSG
eco dings.
PSG eco ds o
58 b uxe s and
58 con ols om a
p i a e clinic.
Cases: 33 women,
25 men; mean age
42.2 ±15.5 yea s.
Con ols: 33 women,
25 men; mean age
42.6 ±14.8 yea s
SB diagnosis was
signi ican ly
associa ed wi h
BMI, alcohol
consump ion, and
changes in sleep
pa ame e s (WASO,
N1, N3, e c.).
J. Clin. Med. 2025,14, 5013 7 o 15
Table 2. Con .
Ti le/Au ho Jou nal/Yea S udy Type Le el o
E idence Objec i e
Ma e ials and Me hods
Conclusions
“Sleep b uxism is highly
p e alen in adul s wi h
obs uc i e sleep apnea:
a la ge-scale
polysomnog aphic
s udy”
(Li e al.) [26]
Jou nal o
Clinical Sleep
Medicine
(2023)
C oss-
sec ional
s udy 3b
To de e mine he
p e alence and isk
ac o s o SB in
adul s wi h OSA
and o analyze he
ela ionship
be ween SB,
a ousals and
espi a o y e en s.
O e nigh ull PSG in
914 adul s (305 women,
609 men) wi h OSA.
SB g oup: 454 pa ien s
(126 women and
328 men)
Non-SB g oup:
460 pa ien s
(179 women and
281 men)
Mean age: 53
±
17 yea s
49.7 % o adul s
wi h OSA had SB.
Male sex, lowe
BMI, and a highe
pe cen age o N1
sleep we e
associa ed wi h a
g ea e SB isk.
“Sleep b uxism and i s
associa ions wi h
insomnia and OSA in
he gene al popula ion
o Sao Paulo”
(Maluly e al.) [27]
Sleep
Medicine
(2020)
C oss-
sec ional
s udy 3b
To e alua e he
associa ion be ween
SB, insomnia, and
OSA in he gene al
popula ion.
Da a om he
EPISONO s udy
(n= 1042; 575 men,
467 women) based on
ques ionnai es and PSG.
G oup A “Possible SB”:
127 pa ien s (47 men
and 80 women)
ou o 1042
G oup B “De ini e SB”:
56 pa ien s (22 men and
34 women) ou o 620
Mean age: Be ween
20–80 yea s
Insomnia is likely
associa ed wi h SB,
especially in
middle-aged
women, whe eas
he ela ionship
wi h OSA a ies by
age and sex.
“Associa ion be ween
sleep b uxism, use o
an idep essan s, and
obs uc i e sleep apnea
synd ome: A
c oss-sec ional s udy”
(Massahud e al.) [28]
Jou nal O al
Rehabili a-
ion (2022)
C oss-
sec ional
s udy 3b
To in es iga e he
associa ion be ween
SB, an idep essan
use and obs uc i e
sleep
apnea–hypopnea
synd ome
(OSAHS).
240 pa ien s (118 men,
122 women) unde wen
ull PSG and clinical
da a collec ion on
an idep essan use.
SB g oup: 103 pa ien s
(62 men and 41 women)
Non-SB g oup:
137 pa ien s (60 men
and 77 women)
Mean age:
51.75 ±15.77 yea s
The ela ionship
be ween
an idep essan use
and SB was
inconclusi e. SB
was mainly
associa ed wi h
se e e OSAHS.
“Obs uc i e sleep
apnea: a ollow-up
p og am in i s ela ion
o empo omandibula
join diso de , sleep
b uxism and o o acial
pain”
(Ning e al.) [29]
BMC O al
Heal h
(2023) Coho s udy 3b
To e alua e he
ela ionship
be ween OSA,
TMD, SB, and
o o acial pain o e
ime.
Follow-up o 71 OSA
pa ien s (45 men,
26 women) assessed a
h ee ime-poin s wi h
PSG, clinical exams, and
CBCT.
Mean age:
36 ±3.5 yea s
Mode a e- o-se e e
OSA wo sens
o o acial pain and
den al wea , a ec s
TMJ
olume/su ace
a ea, and can
change condyla
posi ion; p ope
OSA he apy may
alle ia e hese
e ec s.
“Rela ionships be ween
espi a o y and
o omo o e en s di e
be ween mo o
pheno ypes in pa ien s
wi h obs uc i e sleep
apnea”
(Oku a e al.) [30]
F on ie s in
Neu ology
(2023)
C oss-
sec ional
s udy 3b
To in es iga e he
ela ionship
be ween SB and
OSA in ela ion o
sleep a chi ec u e.
PSG o 36 OSA pa ien s;
compa ison o sleep,
espi a o y and
o omo o a iables
be ween hose wi h and
wi hou SB.
OSA g oup: 26 pa ien s
(20 men and 6 women).
Mean age:
49.7 ±14.1 yea s.
OSA+SB g oup:
10 pa ien s (9 men and
1 woman). Mean age:
49.3 ±15.2 yea s.
OSA pa ien s wi h
SB show a unique
pheno ype wi h a
highe REM
pe cen age, lowe
REM AHI, and
g ea e RMMA
linked o
espi a o y e en s.
J. Clin. Med. 2025,14, 5013 8 o 15
Table 2. Con .
Ti le/Au ho Jou nal/Yea S udy Type Le el o
E idence Objec i e
Ma e ials and Me hods
Conclusions
Is he e an associa ion
be ween sleep b uxism
and obs uc i e sleep
apnea? A case-con ol
polysomnog aphic
in es iga ion.
(Cid-Ve dejo e al.) [33]
Sleep
Medicine
(2024)
Case–con ol
s udy 3b
To es ima e he
associa ion be ween
sleep b uxism (SB)
and obs uc i e
sleep apnea (OSA)
based on he
se e i y o he
la e .
37 pa ien s (24 men and
13 women) wi h and
wi hou OSA unde wen
ull-nigh PSG.
Case g oup: 37 pa ien s
(16 wi hou OSA and
21 wi hou SB)
Con ol g oup:
37 pa ien s (21 wi h
OSA and 16 wi h SB)
Mean age:
49.63 ±11.59 yea s
In pa ien s wi h
subclinical and
mild OSA, SB migh
play a ce ain
p o ec i e ole.
“Incidence o Sleep
B uxism in Di e en
Pheno ypes o
Obs uc i e Sleep
Apnea”
(Sma dz e al.) [31]
Jou nal o
Clinical
Medicine
(2022)
C oss-
sec ional
s udy 3b
To assess he
incidence o SB in
di e en OSA
pheno ypes.
Video PSG o
179 pa ien s:
94 posi ion-dependen ,
85 REM- ela ed.
Posi ion- ela ed OSA
g oup: 34 women and
60 men. Mean age:
52.19 ±13.39 yea s
REM- ela ed OSA
g oup: 28 women and
57 men. Mean age:
51.95 ±13.39 yea s
Posi ion-dependen
OSA seems
associa ed wi h a
highe incidence o
SB and se e e SB,
bu he ela ionship
is no independen .
“Gene ic basis o sleep
b uxism and sleep
apnea— esponse o a
medical puzzle”
(Wieckiewicz e al.) [32]
Scien i ic
Repo s
(2020)
Case–con ol
s udy 3b
To e alua e he
associa ion o
speci ic
single-nucleo ide
polymo phisms
(SNPs) in se o onin-
and
dopamine-pa hway
genes wi h SB and
OSA and o explo e
hei ela ionship.
PCR-based gene ic
analysis o 100 pa ien s
(wi h SB and/o OSA)
and 125 con ols es ing
SNPs s2770304 and
s6313 (HTR2A),
s4680 (COMT)
and s686 (DRD1).
Case g oup: 69 men and
31 women. Mean age:
35.2 ±11.41 yea s
Con ol g oup: 62 men
and 63 women. Mean
age: 29.98 ±9.23 yea s
Possible gene ic
con ibu ion o he
se o onin ecep o
gene HTR2A o SB
e iology; DRD1
s686 may
po en ially
in luence SB isk.
Abb e ia ions: W: woman; M: man; BMI: body mass index; MAD: mandibula ad ancemen de ice; PAP: posi i e
ai way p essu e; AHI: apnea–hypopnea index; SB: sleep b uxism; OSA: obs uc i e sleep apnea; OSAHS: obs uc-
i e sleep apnea-hypopnea-synd ome; JCMA: jaw-closing muscle ac i i y; RMMA: hy hmic mas ica o y muscle
ac i i y; SNP: single-nucleo ide polymo phisms; PSG: polysomnog aphy; WASO: wake ime a e sleep onse .
3.3. Risk o Bias in he A icles and Le el o E idence
The di e en domains used o e alua e bias o each o he s udies a e p esen ed in
Supplemen a y Table S2 o a de ailed assessmen . We applied he ROBINS-I assessmen
scale. All ou a icles ha e a “mode a e” isk o bias.
Among he obse a ional s udies, he mos common sou ce o bias is ou come mea-
su emen , ei he because a single in es iga o is esponsible o he e alua ions o because
i is no speci ied. We also ound pa icipan selec ion bias, whe e speci ic clinical samples
o small samples a e chosen, as well as measu emen bias due o he lack o s anda diza ion
in de ining and quan i ying phenomena such as mas ica o y ac i i y ( hy hmic mas ica o y
muscle ac i i y [RMMA] o jaw closing muscle ac i i y [JCMA]) and sleep apnea.
The Ox o d Cen e o E idence Based Medicine (OCEBM) classi ica ion is a ool ha
allows us o g ade he le el o e idence acco ding o each clinical se ing. This sys ema ic
e iew ca ies a “mode a e le el o e idence” ega ding he associa ion be ween sleep
b uxism and obs uc i e sleep apnea.
This e iew did no include a speci ic assessmen o epo ing bias, such as po en ial
publica ion bias o selec i e ou come epo ing. Gi en he absence o a me a-analy ical
J. Clin. Med. 2025,14, 5013 9 o 15
syn hesis and he lack o egis e ed p o ocols in he included s udies, s anda d app oaches
like unnel plo analysis we e no applicable. We ecognize his as a me hodological
limi a ion ha could in luence he comple eness o he e idence.
3.4. Risk o Bias Ac oss he Included S udies—Ce ain y o E idence Assessmen
The GRADE (G ading o Recommenda ions, Assessmen , De elopmen and E alua-
ion) me hodology was applied o assess he ce ain y o he e idence o he main indings.
The ce ain y o he e idence was classi ied as low o he associa ion be ween b uxism and
obs uc i e sleep apnea (OSA), due o he inconsis ency o esul s ac oss s udies and he
a iabili y in diagnos ic c i e ia. As no me a-analyses we e pe o med in his e iew, we did
no apply o mal s a is ical me hods o de ec po en ial bias due o missing esul s o each
syn hesis. Ne e heless, we acknowledge ha some esul s may be unde epo ed due o
publica ion bias o selec i e epo ing, pa icula ly in s udies wi hou p o ocol egis a ion
o p especi ied ou comes.
4. Discussion
4.1. Me hod
The selec ed a icles show he e ogenei y in me hodology and diagnos ic c i e ia. In
gene al, all he s udies use o e nigh polysomnog aphy (mos equen ly o a single nigh ,
excep Aa ab e al. [
23
] which eco ds wo nigh s) as he “gold s anda d” o diagnosing bo h
apnea and b uxism. Se e al employ addi ional ools such as audio and ideo eco dings
(Sma dz e al., Dadphan e al., Oku a e al., Holanda e al., Cid-Ve dejo, and Wieckiewicz
e al. [
24
,
25
,
30
–
33
]) and sel - epo ques ionnai es in Maluly e al. [
27
], Holanda e al. [
25
],
Cid-Ve dejo e al. [
33
] (Epwo h Sleepiness Scale, Pi sbu gh Sleep Quali y Index, Insomnia
Se e i y Index, e c.) and Ning e al. [
29
] (which also used CBCT, in a-o al images, clinical
examina ion, and isual analogue scales o subjec i e pain assessmen ), and e en eal- ime
PCR ampli ica ion wi h mel ing-cu e analysis in Wieckiewicz e al. [32].
A he sample le el, Maluly e al. [
27
] (EPISONO, n= 1042), s ands ou ; in addi ion
o ha ing a la ge sample, he s udy is based on a gene al-popula ion coho , whe eas he
o he s analyze speci ic clinical samples.
A h eshold o “
≥
2 episodes/hou ” o “
≥
2 RMMA/hou ” is usually used o classi y
he “p esence o SB”. Some a icles (Dadphan e al., Li e al., Cid-Ve dejo e al., Sma dz
e al., Wieckiewicz e al. [
24
,
26
,
31
–
33
]) also se a h eshold o “
≥
4 episodes/hou ” o classi y
se e e b uxism. O he s dis inguish “possible” b uxism (sel - epo ed only) om “de ini e”
b uxism (con i med by PSG) (Maluly e al. [27]).
The s udies included in his e iew exhibi conside able he e ogenei y in hei diag-
nos ic app oaches o bo h OSA and SB. While mos au ho s adhe e o he diagnos ic c i e ia
es ablished by he Ame ican Academy o Sleep Medicine (AASM) o OSA—speci ically, an
apnea–hypopnea index (AHI)
≥
5 wi h symp oms o
≥
15 ega dless o symp oms— he e
is no able a iabili y in how SB is de ined and quan i ied. Some s udies ely solely on
polysomnog aphy (PSG), he gold s anda d, while o he s include sel - epo ques ion-
nai es o combine EMG wi h audio- ideo eco dings. This inconsis ency complica es he
compa ison o esul s and weakens he s eng h o he o e all e idence.
Al hough ea lie e iews ha e examined he possible link be ween sleep b uxism
and obs uc i e sleep apnea, hei conclusions emain limi ed by me hodological conce ns.
The scoping e iew by Paule o e al. [
16
] highligh ed he lack o s anda dized diagnos ic
c i e ia and he b oad a iabili y in s udy designs as key ba ie s o eaching i m con-
clusions. Simila ly, Błaszczyk e al. [
17
], in a ecen me a-analysis, ound no signi ican
associa ion be ween he wo condi ions bu acknowledged ha he o e all quali y o he
a ailable s udies was low and he diagnos ic app oaches inconsis en . These limi a ions
