The Journal
It was reported that the patients with Robin’s
syndrome also demonstrated the sequence of
pharyngeal airway maintainence and of head
11
and neck posture.
The relationship between airway adequacy and
type of malocclusion was studied by Watson in
1968. The incidence of clinically observable
mouth breathing was found to be greater in
subjects with greater nasal resistance 21 .
The functional matrix theory in facial growth
(Moss in 1969), states that cell growth changes
in the size, shape and spatial position and
indeed the very maintenance in being, of all
skeletal units are always secondary to
temporary primary changes in their functional
matrices. Moss calls the pharynx as one of the
primary functional spaces. According to him, it
is the volumetric growth of pharyngeal, oral or
nasal spaces which is the primary
morphogenetic event in facial skull growth 22 .
Some authors like Savoie and Simard
emphasized the importance of the pharyngeal
airway. They described how the tongue would
be held in an altered posture to maintain airway
adequacy if there was even a slight amount of
respiratory embarrassment. This forward or
downward posture of the tongue could lead to
Class III malocclusions 23 .
(at least one standard deviation off), there
would be a 98% chance that the patient was a
mouth breather due to adenoids.
Here a complete or partial adenoidectomy
would seem to be the only solution."
Profitt 26 in 1978 wrote that if there is difficulty in
breathing, the physiological adaptations which
facilitate mouth breathing include a forward
position of the head on the neck and a lowered
position of the mandible with a low and forward
tongue posture.
The development of an anterior open bite can
be brought in cases with respiratory obstruction
(Schulhof;1978). This respiratory obstruction
can also lead to mouth breathing which is the
cause of many orthodontic problems like Class
II malocclusions, buccal cross bite and vertical
growth problems 27 .
18
Quick (1978) used questionnaires to assess
respiratory mode and the frequency of
associated nasal problems. His cephalometric
study of 113 subjects (high versus low
mandibular plane angles) led him to conclude
that, although others have attributed
morphologic features to respiratory behavior, in
reality, breathing mode is a function of
"abnormalities" in skeletodental structures.
28
A study by Aronson in 1974 was done to
demonstrate the changes in craniofacial
morphology due to obstruction of the upper
airway because of enlarged adenoids. It was
then proposed that the lowered position of the
tongue played a significant role in
pathogenesis 24 .
25
Scohulhof (1978) claimed that the use of a
computer-aided cephalometric analysis
provides a definitive method for assessing
airway impairment due to adenoids. He stated
flatly, "If all four measures indicate that the
adenoid is too large for the airway
41
According to Quinn (1978), the ostensible ill
effects of mouth breathing are prognathisms,
facial asymmetries, anterior and posterior open
bites, temperomandibular joint problems, root
resorption, gingival decalcification, rampant
caries, gingival recession, alveolar bone loss,
and periodontal disease.
A
study (Vig,Sarver;1981) examining the
relationship between facial morphology and
respiration, concluded that the respiratory
patterns between lip-incompetent, long faced
and normal persons, when compared in groups
29
are not significantly different .
Vol. 14 No. 2
May-August 2018