protrusive position, to dislocate forward the
tongue via the genioglossus muscles and to
change the position of hyoid bone, thus
expanding the upper airways (Franson et al.
2002 ). It has been found that the application of
MAA only to stimulate the genioglossus muscles
without mandibular advancement has no influ-
ence on the number of obstructive respiratory
events during sleep (Metha et al. 2001). Upon
establishing an optimal mandibular position with
the appliance to reach the therapeutic goal, a
control polysomnographic examination should
be performed to assess the device efficacy,
since in some patients MAA may inadvertently
increase the number of apneic events (Ferguson
et al. 1997 ). Nevertheless, numerous findings
confirm the overall effectiveness of mandibular
advancement devices for OSA treatment. The
results of magnetic resonance imaging and endo-
scopic examinations provide evidence that MAA
application expands the volume of upper airways
(Gao et al. 1999 ).
Hoffstein ( 2007 ) has divided the adverse
effects of mandibular advancement appliances
into three groups: mild-transient, moderate-to-
severe, and continuous. Excess salivation, dry
mouth, allergic reactions to the applied materials,
and pain in temporomandibular joints are the
adverse effects observed most frequently. The
available literature reports that cephalometric
findings and model analyses reveal changes in
the overjet and overbite, maloclusion, changes in
the upper incisor angle to cranial base (1/NS) and
the angle between Sella-Nasion-Supramentale
point after MAA application (Fritsch et al.
2001 ). In a study carried out to assess the
effects of the Herbst mandibular advancement
appliances employed for two years, Battagel
and Kotecha ( 2005 ) have observed changes in
the position of incisors, insignificantly dimin-
ished overjet, and the overbite correlation with
the splint vertical dimension. These changes
were related neither to the degree of mandibular
advancement nor the period of device use.
Fransson et al. ( 2003 ) have reported similar
findings. Investigating the effect of MAA on the
stomatognathic system, Rinqvist et al. ( 2003 )
have used splints that do not cover the anterior
region of the dental arch, with the mandibular
advancement not exceeding 50 %. The authors
did not notice dental abnormalities in the form of
changed overjet, overbite, or inclination angle of
upper and lower incisors. Marklund et al. ( 2004 )
have rarely observed adverse effects with the use
of devices produced of soft material. On the other
hand, Bondemark and Lindman ( 2000 ) have
found that devices made of hard material better
prevent upper airway occlusion, giving a full
support to dental arches. Martinez-Gomis
et al. ( 2010 ) have shown that the majority of
dental changes occur during the first two years
of using mandibular advancement appliances.8 ConclusionsThe available research demonstrates that treat-
ment of obstructive sleep apnea with mandibular
advancement appliances is well grounded. The
use of such appliances is an effective therapeutic
alternative in carefully selected clinical forms of
OSA and may give an edge over the standard
CPAP treatment. Mandibular advancement
appliances seem a particularly attractive thera-
peutic alternative in mild-to-moderate OSA and
in CPAP intolerant patients. These appliances
also have a distinct reducing effect on the over-
whelming feeling of daily sleepiness. It should be
borne in mind that OSA is a disease of many
faces, due to, among others, different severity
of disease at onset, and differences in morphol-
ogy and duration of treatment. The response to
treatment may thus be highly and unpredictably
variable.Conflicts of Interest The authors declare no conflicts of
interest in relation to this article.ReferencesAarab G, Lobbezzo F, Hamburger HL, Naeije M (2011)
Oral appliance therapy versus nasal continuous posi-
tive airway pressure in obstructive sleep apnea; a
randomized, placebo-controlled trial. Respiration
81:411–419Mandibular Advancement Appliance for Obstructive Sleep Apnea Treatment 69