Linkage of nitric oxide with chronic periodontitis,

1. ISP Regd. No. - 87

2.  Chronic periodontitis is defined as an
inflammatory infectious disease
resulting in clinical attachment loss,
pocket formation, gingival
inflammation and alveolar bone loss.
 It is a multifactorial disease caused
by dental plaque microorganisms
 Smoking is a known risk factor for
many diseases and evidence suggests it
negatively impacts periodontal health

3. Smoking is a single modifiable environmental risk factor
responsible for excess prevalence of periodontal
disease

4. Increased
pocket
depth
Increased
attachment
loss
Decreased
bleeding
Increased
prevalence
of
inflammator
y cytokines
Increased
anaerobic
bacterial
count

5. Cytokines and other bacterial products stimulate the expression
of iNOS which further participates in inflammatory reaction
and causes tissue damage
NO Free
radical
Synthesized
through NOS
iNOS
eNOS
nNOS

6.  In vivo, NO combines with Oxygen and produces Nitrite and Nitrate,
which can be used to measure the level of NO
 Hence it was decided to evaluate the level of NO in saliva of smoker and
non smoker patients with chronic Periodonitis with those of normal
individuals

7.  The aim of this study was to assess the changes in clinical
parameters namely Plaque Index, Gingival Index, Clinical
attachment level, Probing pocket depth, Recession depth,
Bleeding on probing % and salivary Nitric Oxide levels in
both smoker and non smoker patients with chronic
periodontitis

8. GROUP 1
N=20
periodontally
healthy
individuals
GROUP2
N= 20 non
smokers with
chronic
periodontitis
GROUP3
N= 20
smokers
with chronic
periodontitis
Individuals for the
study were categorised
as follows
 Materials and Method

9.  Inclusion criteria for Chronic Periodontitis
patients
•Patients aged above 18 years
•Non-smokers having chronic generalised periodontitis (group II )
Smokers having chronic generalised periodontitis (group III)
•Patients with moderate to severe clinical attachment loss in ≥ 30 percent of the sites.
•Presence of ≥10 teeth per dental arch.
•In case of group III, patients smoking >10 cigarettes per day for the last 5 years
•Patients with probing pocket depth ≥ 5mm

10.  Exclusion criteria
•Patients having any systemic disease.
•Patients having history of previous
periodontal therapy
•Patients who have received any previous
antioxidant or anti-microbial therapy.
•Alcoholics
•Females

11. DATA COLLECTION
Patients deemed fit for inclusion in the study were further
evaluated according to the clinical parameters namely:
1) Plaque Index
2) Gingival Index
3) Probing Pocket depth
4) Clinical Attachment Level
5) Recession depth
6) Bleeding on Probing %
The Nitric Oxide levels were assessed after taking a saliva sample of the patient by
asking the patient to spit into a sterile container

12.  -MEDICAL HISTORY: High blood pressure, Diabetes
mellitus
SOCIAL HABITS
 Alcohol / other drug intake
 -HISTORY of TRAUMA/ILLNESS: For patients taking
antibiotics/other pharmaceutical treatment
 -DENTAL HISTORY: In order to ascertain whether
patient has undergone or is undergoing any dental
treatment in the past 6 months

13.  Unstimulated saliva samples were collected from subjects of Group I, II
and III at baseline and four weeks post-treatment from the patients, about
two ours after breakfast.
 Patients were instructed to void the mouth of saliva prior to collection, by
rinsing the mouth thoroughly with deionised water to wash out any debris
or exfoliated cells.

14.  The following indices were utilised in order to evaluate the
oral hygiene of the patients:
 Plaque Index (Silness and Loe et al, 1964)
 Gingival Index (Loe and Silness et al, 1963)

15. Clinical Armamentarium

21.  After 1 month follow up all the clinical and biochemical parameters
were re evaluated using the aforementioned methods and
subsequently the following Statistical tests were applied:
 1) Normality test
 2) Analysis of Variance test (ANOVA)
 3) t Test – Paired and Unpaired
 The analysis was performed with a statistical software package for
social sciences version 17.0 (SPSS, Version 17.0 ,Inc, Chicago).
 The results were considered statistically highly significant when the
P value was <0.001 and statistically significant when the P value
was <0.05.

29.  In light of the above results the discussion about various parameters is as
follows:
 No significant difference was found in the clinical parameters of Age,
Plaque Index Recession depth and Probing Pocket Depth at baseline
between smoker and non smoker groups although the difference was
significant when compared to the normal/control group
 The parameters namely Gingival Index , Nitric Oxide levels, Clinical
attachment level and Bleeding on Probing % varied significantly at
baseline

30. After evaluation of the clinical and biochemical parameters at baseline the
patients were called up for re evaluation after a period of 1month/ 4 weeks
The following points were noted at re-evaluation:
The Plaque Index and Gingival Index was decreased in both smokers and non
smokers and the differences between the two groups were statistically
significant, which was in conformity with the studies done by Preber and
Bergstrom et al and Ji- Yeon Shim et al
The Probing Pocket Depth reduction and Gain in clinical attachment was
seen in both smokers and non smokers but in non smokers was to a far
greater extent than smokers and the result was in conformity Grossi SG,
DeCaro T et al and Haffajee AD et al
No significant variations were seen in Recession depth either before or
after SRP in both the groups

31.  Probing Pocket Depth reduction and Gain in clinical
attachment level was not as significant in smokers as non
smokers because :
 1) Nicotine decreases fibroblast attachment at root surface
thus decreasing rate of wound healing
 2) Decreases collagen production
 3) Increases collagenase production (Cuff MJ, Mcquade
MJ et al, Gamal AY et al)

32.  Nitric Oxide levels also showed reduction in both smoker and non smoker
groups after SRP. The result was in conformity with a study conducted by
Poorsattar Bejeh- Mir et al
 Other studies on Nitric Oxide conducted by other workers such as
Menaka B et al, Mani Sundar N et al, Wadhawa D et al also evaluated
the role of Nitric Oxide as an inflammatory biomarker and compared its
levels in smoker and non smoker patients and found a significant difference
at baseline levels
 The levels of Nitric Oxide showed increase in periodontitis patients
which was attributed to the fact that there increased levels of iNOS
expressing cells during the inflammation of the periodontal tissues
(Reher VG et al)
 Nitrite is converted non enzymatically to NO at low pH but the rate of
this conversion becomes low at normal pH (6.2-7) and can explain for
the low salivary NO values in Periodontally healthy individuals (Mani
Sundar et al)

33.  Bleeding on probing % was decreased significantly in case of non
smokers due to disruption of plaque bio film and subsequent decrease in
inflammation while smokers showed significantly increased tendency for
bleeding as the effect of nicotine and tar waned and their effect on
periodontal tissues also decreased. This result was in conformity with
studies conducted by Preber and Bergstrom et al, Ji-Yeon Shim et al
 The increased tendency for the soft tissues to bleed in non smoker
patients may be due the fact that there is an inhibitory effect of NO on
platelet aggregation along with adhesion inhibition (Mani Sundar et al)

34.  1) Small sample size
 2) Other influencing factors such as stress and dietary factors
that cannot be controlled and may influence NO levels
 3) Periodontally healthy patients were assumed to have
maintained their original oral hygiene levels after 1 month as
even a slight change would have produced distorted readings

35.  The findings clearly suggest that NO levels are increased in
patients with periodontitis compared to healthy controls
 The role of NO in inflammation represents one of the most
studied yet controversial subject
 However the precise role of NO in tissue damage in
periodontal disease remains unclear
 Further studies must be undertaken to know the multiple
signaling pathways that are involved in production of NO that
may help in designing new therapeutic strategies