Periodontal disease status and treatment need among a Kurdish population in Sulaimani/ Iraq as assessed by CPITN index.

Background This study identifies the prevalence and severity of periodontal diseases in a given population of Sulaimani using the Community Periodontal Index of Treatment Needs (CPITN) and attempts to find the relation of CPITN with age, sex, location, visit to dentist, tooth brushing, use of mouth wash and interdental aids, systemic disease, smoking status and missing teeth. Methods Subjects attending Periodontics clinics at College of Dentistry, University of Sulaimani were examined. Periodontal examinations were performed using CPITN, plaque index (PI) and bleeding index (BI). Other data including location, visit to dentist, tooth brushing, use of mouth wash and interdental aids, presence of systemic diseases, smoking status and missing teeth were also collected. The data were subjected to logistic regression to find a relation between periodontal status (CPITN ≥ 3 or not as dependent variable) and other variables. Results Among the 1354 subjects (mean age 30.8 ± 12.9 years) examined, 43.6% were male and the majority of these (80.9%) were from urban areas. The mean PI and BI were 0.64±24 and 0.39±0.28, respectively. Calculus was the most prevalent highest score amongst examined subjects (62.2%), followed by shallow pocket (22.2%) and bleeding (9%). Among the sextants, lower central sextants were found to have the highest percentage of calculus (73.1%), followed by lower left (49.7%) and lower right (48.7%). The highest percentages of shallow and deep pockets were found at upper left (14%, 2.5%, respectively) and upper right (11.4%, 3.2%, respectively) sextants. Logistic regression analysis showed that age, sex, frequency of brushing and smoking significantly correlated with CPITN scores.

3 impact on periodontal condition.

Background
Periodontal diseases are a group of diseases that affect supporting structures of the teeth and are considered as a main cause of tooth loss in adults worldwide. Although they share similar aetiologies, different natural courses, prognoses and responses to conventional therapy have been reported (1). The Community Periodontal Index of Treatment Needs (CPITN) is supported by both the World Dental Federation (FDI) and World Health Organization (WHO) as epidemiological screening criteria to determine periodontal treatment needs in a population. The CPITN has been used widely to plan for health services; furthermore, the data retrieved from it provide a base to determine the needs of the overall population in terms of the requirements for specific types of treatment and the clinical personnel involved in periodontal care (2). Tooth cleanliness, as measured by plaque and calculus accumulation, plays an essential role in periodontal health (6). In adults with periodontal disease, oral health-related quality of life can be moderately improved through basic periodontal treatments (7) including routine non-surgical therapies and removal of dental biofilms and biofilmretentive calculus by mechanical means (i.e., scaling and root surface debridement) (8).
Since the 1940s, there has been great general interest among epidemiologists in development of a suitable index system for quantification of the prevalence and severity of periodontal diseases in individuals as well as in population groups in all parts of the world (9). The CPITN was jointly developed by the WHO and FDI (10) and since then it has been used worldwide to study periodontal disease in populations at community level, as well as the related treatment needs. It is claimed to be a simple, rapid, inexpensive, easily applied index which requires minimum equipment and has an international uniformity (11). However, baseline data on periodontal knowledge, prevalence and severity of The data were obtained through a data collection sheet that recorded the following: age (age group <20, 20-29, 30-39, 40-49, 50-59 and ≥60), sex, location (urban and rural), visit to dentist (No, regular and irregular), tooth brushing (no brushing or how many times per day), use of interdental hygiene (yes or no) and type (dental floss, interdental brush, single tufted brush), systemic disease (such as diabetes, hypertension), smoking status (yes or no) and if yes: how many cigarettes per day and missing teeth. Periodontal condition was assessed by CPITN index, bleeding index (BI) and plaque index (PI) of all teeth using WHO probe (12) (Figure 1). The CPITN is a practical index for population-based surveys. It is used as an indicator of periodontal status in a specific community or population (13). The CPITN measures the following conditions: no treatment needs (score 0), bleeding gingiva on gentle probing (score 1), presence of supra or subgingival calculus or other plaque retentive factors (score 2), 4 to 5mm PPD (score 3), and ≥ 6 mm PPD (score 4) (14). The dentition was divided into sextants and the highest scores in terms of the worst periodontal condition around each tooth in that sextant were recorded.

Statistical analysis
Advice was taken from an expert statistician. Continuous data (age, missing teeth, PI and BI) were subjected first to the Shapiro-Wilk test for normal distribution and thereafter to appropriate parametric or nonparametric tests. A single overall CPITN score, calculated as the maximum score found over each sextant, was assigned to each sextant and the highest score in all sextants was assigned to each subject. Periodontal condition was then presented as percentage per given population. The highest CPITN score per subject was used an outcome dependent variable dichotomized using accepted thresholds (15) of low (CPITN < 3) and high (CPITN ≥ 3) for multiple logistic regression modeling. The association between periodontal condition and other confounders such as age, sex, location, visit to dentist, tooth brushing, use of interdental hygiene, systemic disease and smoking status and missing teeth was determined by logistic regression using the highest CPITN score per subject. Statistical significance was defined as p ≤ 0.05. All calculations were performed using the SPSS software package (version 21; SPSS Inc., Chicago, IL, USA).

Results
During the study 1354 subjects (43.6% male and 56.4% female) with mean age of 30.812.9 years were examined. The median of missing teeth in the examined population is 4 teeth (inter quartile range 2-8 teeth) with mean PI of 0.6424 and mean BI of 0.390.28 ( Figure 2). The majority of subjects were from urban areas (80.9%) and visited the dentist irregularly (81.3%) ( Table 1). Just above half of the examined subjects brushed their teeth once a day and 67.1% did not use interdental aids, while mouth wash was used by only 8.3% (Table 1). Systemic diseases such as hypertension and diabetes were detected in only 5.7% and 4.2% of the examined population, respectively, and 79.2% were nonsmokers (Table 1).
Logistic regression was used to determine the relations between the examined variables population level. Further studies with larger sample size and full mouth examination are recommended. Furthermore, in Sulaimani, this study shows that periodontal condition and oral hygiene standards need improvement. Therefore, to prevent and control periodontal disease, a comprehensive intervention program is recommended at regional level.   Figure 1 Periodontal examination by WHO probe Figure 2 Mean plaque index and bleeding index of examined subjects.

Figure 3
Periodontal condition of whole mouth using CPITN index.

Figure 4
Periodontal condition in each sextant using CPITN index.