Abstracts of the Academy of Dental Materials Annual ... - IsiRed

e74 dental materials 26S (2010) e1–e84
useful to study different healing phases because the osseointegration
is not anymore influenced by this factor after this
duration. Finally, histological analysis/histomorphometric is
particularly suitable because it allows, by itself, to evaluate
different parameters characterizing the tissue-implant interface.
doi:10.1016/j.dental.2010.08.165
158
Mild-acidic HOCl solution as pretreatment for caries-affected
dentin: A morphological study
S. Kunawarote 1,2 , M. Nakajima 1 , S. Ichinose 1 , J. Tagami 1,2
1 Tokyo Medical and Dental University, Japan
2 Global Centre of Excellence Program, International Research Centre
for Molecular Sciences in Tooth and Bone Diseases, Japan
Objectives: To evaluate the pretreatment effects of NaOCl
and mild acidic hypochlorous acid (HOCl) solutions on normal
and caries-affected dentin surfaces covered with smear
layer by SEM and to investigate the interfaces between there
pretreated dentin surfaces and self-etch adhesive using TEM.
Materials and methods: Coronal dentin surface with
caries-affected surrounding normal dentin were prepared
from extracted human molars. Dentin surfaces with standardized
smear layer were treated with 6% NaOCl, 50 or
100 ppm HOCl (Comfosy ® ) solutions for 5 s and their morphological
alterations were observed with SEM. Other pretreated
dentin surfaces were bonded with self-etch adhesive: Clearfil
SE Bond, and then the interfaces of normal and caries-affected
dentin were investigated by TEM.
Results: SEM micrographs showed that smear layer on
normal dentin had a uniform texture with compact crust of
cutting debris, while caries-affected dentin was covered with
thicker and irregular smear layer with a fuzzy texture, in which
the fibril-like structures were observed. All of pretreatments
demonstrated unnoticeable alterations in smear layer-covered
normal dentin surfaces. On the other hand, the smear layers of
caries-affected dentin were thinned and partially dissolved to
various degrees. For TEM observation, all pretreatment solutions
had unnoticeable effect on morphological characteristics
of bonded normal dentin interface, except for fewer remnants
of smear layer. Bonded caries-affected dentin exhibited irregular
interface with the thicker and poorer hybrid layer, in
which a thick hybridized smear layer was evident with the
“fuzzy carpet” appearance along the top of hybrid layer. However,
pretreatment with 50 and 100 ppm Comfosy ® created a
thinner and uniform hybrid layer, in which the fuzzy carpet
appearance was absent.
Conclusions: The result of this study suggested that pretreatment
with mild acidic HOCl solutions on caries-affected
dentin appears to dissolve and remove the organic components
within the thick smear layer of caries-affected dentin,
which may improve the adhesive infiltration through the
smear layer of caries-affected dentin.
doi:10.1016/j.dental.2010.08.166
159
Chlorhexidine and fluoride: A reduction of Streptococcus
mutans in orthodontic patients with special needs
L. Laffranchi, I. Casula, F. Luparia, E. Marchesini, D.
Dalessandri, C. Paganelli
Dental School University of Brescia, Brescia, Italy
Objectives: To evaluate the relationship between S. mutans
and total streptococci in “special needs” patients treated in
the Department of Orthodontics-Dental Clinic-University of
Brescia subjected to a home treatment based on mouthwash
that lowered significantly the level of S. mutans.
Materials and Methods: 60 patients (aged 6–16 years),
23 M–37 F, 56 suffering from S. Down, 2 S. Williams, 1 S
Rubinstein–Taby, were divided into 3 groups. Each group
rinsed once a day for 4 weeks respectively with mouthwash:
Dentosan ® (chlorhexidine 0.12% no alcohol, Johnson & Johnson),
Oral-B ® Fluorinse (sodium fluoride 0.2%), saline 0.9%
NaCl. The bacterial load was assessed through microbiological
testing at T0, T1 (after 2 weeks) and T2 (after 4 weeks from T0)
with sampling saliva obtained before any dental treatment,
chewing a paraffin tablet for 60 s. We analyzed the data with
Anova test and t-test in order to statistically verify which of the
three procedures has given the best results, comparing Group
I: TO vs T1, T1 vs T2, T0 vs T2; Group II: TO vs T1, T1 vs T2, T0
vs T2; Group III: TO vs T1, T1 vs T2, T0 vs T2.
Results:
S. mutans T0–T1 T1–T2 T0–T2
Group 1 Reduced 36.2% Reduced 61.4% Reduced
75.4%
Group 2 Reduced 31.3% Reduced 32.6% Reduced
53.7%
Group 3 Increased 20% Increased 32.3% Increased
15.4%
S. Total T0–T1 T1–T2 T0–T2
Group 1 Reduced 14.5% Reduced 19.8% Reduced
31.4%
Group 2 Reduced 5.9% Reduced 8% Reduced
13.4%
Group 3 Increased 14.5% Increased 19.8% Increased
31.4%
The Anova and Bonferroni’s tests showed that the mean
concentration values of the S. Mutans in the 3 considered
groups were not statistically significant (p = 0.44878). The t-test
showed that in group 1 the results were statistically significant
with a p-value = 0.00113 for T0 vs. T1, p = 0.00003 for T1 vs T2,
p = 0.00011 for T0 vs T2. In group 2 the results were statistically
significant with a p-value = 0.00158 for T0 vs. T1, p = 0.01902 for
T1 vs T2, p = 0.00004 for T0 vs T2. In group 3 the results were
not statistically significant with a p-value = 0.49435 for T0 vs.
T1, p = 0.15434 for T1 vs T2 and p = 0.18050 for T0 vs T2.
Conclusions: Although our study needs to increase the
number of samples and involve other types of patients (not
just special needs), the results show that the significant reduc-