except for the fact that patients o

except for the fact that patients of the control group
received sham-laser.
The ®rst session was performed at the ®rst day of RT,
and the following sessions occurred three times a week on
alternate days, always before each session of RT, until the
end of the treatment. Just to emphasize, all patients
received concomitant chemotherapy during RT.
Oral Mucositis Evaluation
OM was evaluated weekly by the same trained dentist,
blinded to the randomization. The operator who performed
the laser irradiation did not participate in the OM
evaluation.
The severity of OM was rated according to the National
Cancer Institute (NCI) and the World Health Organization
(WHO) grading of mucositis scales. These classi®cations
are widely used both in routine clinical practice and in
clinical trials involving OM. During the oral examination,
OM severity was rated as follows:
1. NCI scale: Score 0Ðoral mucosa presenting no visible
alteration; Score 1Ðpresence of erythema; Score 2Ð
ulcers up to 1.5cm in diameter and noncontiguous;
Score 3Ðulcers larger than 1.5cm in diameter and
contiguous; and Score 4Ðulcers showing necrosis and
bleeding.
2. WHO scale: Score 0Ðno signs or symptoms; Score 1Ð
oral soreness and erythema; Score 2Ðoral erythema
and ulcers, both solid and liquid diets tolerated; Score
3Ðoral ulcers, liquid diet only; Score 4Ðoral alimentation
impossible.
Saliva Collection
Saliva samples were obtained at one point before
chemoradiotherapy and at three points during the
treatment (7th, 21st, and 35th sessions of RT) according
to the spitting method proposed by Navazesh [24]. Patients
could not eat or drink an hour before saliva collection
procedure. They washed the mouth with pure water and
swallowed whole saliva before collection.
For unstimulated saliva collection, patients were instructed
to slightly tilt their head down and then they
should expectorate the saliva, which was produced over a