Clinical Trial Details
— Status: Completed
Administrative data
| NCT number |
NCT05484765 |
| Other study ID # |
ESGHDEOECP |
| Secondary ID |
|
| Status |
Completed |
| Phase |
|
| First received |
|
| Last updated |
|
| Start date |
November 1, 2018 |
| Est. completion date |
July 20, 2019 |
Study information
| Verified date |
September 2023 |
| Source |
Istanbul Medipol University Hospital |
| Contact |
n/a |
| Is FDA regulated |
No |
| Health authority |
|
| Study type |
Observational [Patient Registry]
|
Clinical Trial Summary
Smoking negatively affects the prognosis of periodontal disease by impairing tissue healing.
While micronucleus is the most popular parameter for demonstrating DNA damage, inflammatory
cell and vascular densities are the most evaluated parameters for determining histopathologic
changes in the periodontium. This cross-sectional study aimed to evaluate the effects of
heavy cigarette smoking and generalized periodontitis on local genotoxic damage to exfoliated
oral epithelial cells as well as histopathologic damage to the periodontium. The
investigators hypothesized that the genotoxic and histopathologic damage would be increased
in smokers with generalized periodontitis.
Description:
Study design and Setting This was a single-center, investigator-blinded, cross-sectional
study. Work was conducted at the Department of Periodontology in Istanbul, Turkey, between
November 2018 and July 2019. The study procedure was conducted according to the guidelines of
the Declaration of Helsinki and approved by the Ethics Committee of the university (Protocol
code: 10840098-604.01.01-E.47596&10840098-604.01.01-E.4759; date of approval: 30 October
2018). Data from six non-smoking participants with healthy periodontium from our previous
studies were used in this study as well. After the study was verbally explained to eligible
subjects, those willing to participate signed a written, informed consent form. Personal,
identifiable information about the subjects was kept confidential. The study was reviewed
following the Strengthening the Reporting of Observational Studies in Epidemiology
guidelines.
Participants Eighty systemically healthy subjects, both male and female, were enrolled in the
study. Participants were recruited from patients who came to our department for periodontal
examinations between November 2018 and July 2019. Diagnoses of clinically healthy
periodontium and generalized periodontitis stages III-IV/grades B-C were performed according
to the 2017 World Workshop on the Classification of Periodontal and Peri-implant Diseases and
Conditions. Subjects were separated into four groups: smokers with generalized periodontitis
(SGP; n = 20), non-smokers with generalized periodontitis (NGP; n = 20), smokers with
clinically healthy periodontium (SHP; n = 20), and non-smokers with clinically healthy
periodontium (NHP; n = 20). The following criteria needed to be met to be considered a
periodontitis subject: the presence of generalized periodontitis, the presence of at least 20
teeth, the presence of a molar with an indication of gingivectomy, crown lengthening or
extraction with a probing depth ≥ 5mm, clinical attachment loss ≥ 5 mm, and the presence of
at least ten teeth with a probing depth ≥ 5 mm. The following criteria indicated a clinically
healthy periodontium: a healthy and intact periodontium, no probing depth and bleeding on
probing.
Clinical procedure All subjects answered a questionnaire that assessed age, gender, and
educational level. A clinical evaluation of periodontal disease was conducted according to
international standards. The CPPs, including plaque index, probing depth, bleeding on
probing, and clinical attachment loss, were recorded from six sites per tooth from each
subject using a periodontal probe by the same researcher. The sample collection and
histopathologic evaluation procedures were performed as in our previous report. Briefly,
smear samples were collected from the attached gingival mucosa of the upper premolar-molar
area and the buccal mucosa of the matching cheek using two separate sterile cytobrushes.
Samples were fixed on glass slides. Biopsy samples were taken from the vestibular area of the
maxillary molars during tooth extraction or crown lengthening using a surgical blade and
fixed in 10% formalin until analysis. During microscopic inspection, each subject rinsed
their mouth before samples were obtained to reduce the possibility of artifacts through
chromatin remainders.
Laboratory procedure To evaluate the exfoliated oral epithelial cells containing micronuclei
counts (the primary outcome), the Feulgen reaction was performed on all smear samples. Cells
were placed in a fixative for nuclear staining and analysis using Schiff's reagent.
Micronuclei in the buccal and gingival smear samples were analyzed by observing them in oil
immersion at 1000× magnification. One thousand cells were checked, and the count of
micronuclei present was assessed. The occurrence of nuclear morphological changes, such as
the presence of two nuclei within a cell, nuclei that appeared cinched with a Feulgen
negative band, shrunken nuclei, condensed chromatin, nuclear disintegration involving the
loss of nuclear integrity, and nuclear dissolution was estimated. A zigzag strategy was used
to calculate the cells.
Histopathologic damage (the secondary outcome) was evaluated by focusing on inflammatory cell
and vascular densities. Damage was assessed using a modified semi-quantitative
histopathologic assessment method using a scale ranging from 0 to 3 (0: none, 1: mild, 2:
moderate, and 3: intense). Tissue samples were fixed in paraffin wax, serially sectioned at a
4 µm thickness, stained with hematoxylin-eosin, and examined at 400× magnification. All smear
and tissue samples were assayed concurrently and in the same laboratory by the same blinded
investigator.
Bias The evaluation of each participant's systemic health status, dental history, and smoking
habits was based on self-reported information regardless of official medical records. One
researcher collected the data and samples from the participants while another researcher
undertook the laboratory investigations. To avoid bias, five sample areas were randomly
selected during the histologic examinations.
Study size The sample size was determined using G*Power version 3.1.9.4, assuming an alpha
significance level of 0.05, a beta value of 0.1, and 90% power. As there were four study
groups and a need for 20 participants per group, eighty subjects were included in the study.
Statistical methods The Number Cruncher Statistical System 2007 software program was used for
all statistical analyses. Descriptive statistics (mean, standard deviation, median) were used
to evaluate the data. The one-way analysis of variance test was used to compare the means of
three or more normally distributed parameters. The Bonferroni test was used to determine the
significant differences in pairwise comparisons between the groups. The Pearson chi-square
test was used to compare qualitative data. Significance was evaluated at the p<0.01 and
p<0.05 levels.
