Abstract
Background
A self‐reported questionnaire developed by the Centers for Disease Control and Prevention and American Academy of Periodontology (CDC/AAP) has demonstrated adequate reliability for evaluating periodontal status in national surveillance surveys—–which has been translated and validated in multiple languages–—but has not yet been tested in Thai. Therefore, this cross‐sectional study evaluated the validity of the CDC/AAP self‑report questionnaire for periodontitis in a Thai population.
Methods
The Thai version of CDC/AAP self‐reported questionnaire was developed. Full‐mouth periodontal examinations were performed, and periodontitis was diagnosed using CDC/AAP 2012 or European Federation of Periodontology (EFP)/AAP 2018 case definition. Association between questionnaire responses and a periodontitis diagnosis was assessed using multiple regression modeling. Several predictive models were constructed and their validity assessed using receiver operating characteristic curves.
Results
The study included 250 participants resided in Chiang Mai, Thailand, aged 20–82 years, with 83.6% and 84.4% diagnosed with periodontitis based on CDC/AAP 2012 and EFP/AAP 2018 case definitions, respectively. CDC/AAP questions revealed a satisfactory performance in predicting CDC/AAP‐defined severe periodontitis and EFP/AAP‐defined stage III/IV periodontitis. Additional questions regarding demographic data and periodontal risk factors improved the performance. Reduced model constructed using stepwise regression yielded sensitivity versus specificity of 57.8% versus 84.0% and 79.4% versus 81.4% for predicting CDC/AAP‐defined severe periodontitis and EFP/AAP‐defined stage III/IV periodontitis, respectively.
Conclusions
The questionnaire in Thai version demonstrated better performance in predicting advanced stages of periodontitis when combined with demographic variables and periodontal risk factors. Our findings highlight the potential utility of this tool in diverse populations.
Plain language summary
Despite being one of the most common diseases in humans, periodontal disease diagnosis is not easy at the individual and surveillance levels. Efforts have been made to assemble tools to ease the process, and questionnaires are an auspicious tool. This study aimed to validate the self‐reported questionnaire developed by the US Centers for Disease Control and Prevention in collaboration with the American Academy of Periodontology for predicting periodontal disease in the Thai population. The validity of the questionnaires was assessed by comparing the self‐reported responses to the data collected through a full‐mouth examination by a third‐year resident from the Periodontology Residency Training Program. In our study, questions related to signs of the disease showed promising validity as a predictive variable for periodontitis, especially its severe form, and the questionnaires performed better when used together with other questions, such as age and education level.
Keywords: periodontal disease, periodontitis, questionnaires, Thai, validity
1. INTRODUCTION
Periodontal disease is a chronic inflammatory disease of periodontium, with dental plaque or biofilm as the primary etiology. Periodontal diseases are categorized into gingivitis, in which inflammation is limited to gingiva, and periodontitis, where inflammation affects periodontal tissues. Additionally, periodontitis is a multifactorial disease influenced by genetics, host immune‐inflammatory response, and environmental and lifestyle factors. 1 Untreated periodontitis is a major cause of tooth loss and contributes to poor quality of life. 2
Globally, periodontitis is highly prevalent, ranging 25%–50% in different populations. 3 In Thailand, the Ninth National Oral Health Survey (NOHS) 4 reported that 32.6% of adults aged 35–44 years and 48.7% of those aged 60–74 years had periodontitis, with 9.2% and 18.7% of them had deep periodontal pockets (>6 mm), respectively. However, approximately 30% had received dental treatment, and the major reasons for visiting a dental professional were dental problems. Periodontal disease progression can be prolonged through proper oral health behaviors and early diagnosis. 5 However, its asymptomatic nature and low awareness lead to treatment postponement, resulting in more complicated treatment and poor prognosis. Therefore, it is important to enhance awareness of periodontal health and early diagnosis. 2 , 5
Periodontal disease diagnosis requires the collection of clinical and radiographic data, which is time‐consuming and requires dental professionals, instruments, and resources. To overcome these issues, self‐reported questionnaires for disease assessment have been developed and tested in various studies over the past decades. 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13
In 2003, the US Centers for Disease Control and Prevention (CDC), in collaboration with the American Academy of Periodontology (AAP), proposed acceptable levels of validity for public health surveillance of periodontitis, periodontitis classification, and a self‐report questionnaire for population‐based surveillance of periodontitis (see Table S1 in online Journal of Periodontology). 14 The questions underwent cognitive assessments and were validated in groups of the US population. Finally, an eight‐item self‐reported questionnaire in English and Spanish was developed and tested in the 2009–2010 National Health and Nutrition Examination Survey (NHANES). 8 Additionally, the questionnaire has been translated into several languages, including French, 15 Portuguese, 16 , 17 Dutch, 18 , 19 Japanese, 13 , 20 and Chinese, 21 and tested in diverse populations, as its validity and predictable capability vary across different groups. 22 The availability of validated tools in multiple languages enhances the feasibility of widespread surveillance and early detection efforts. These results offer a framework that may inform similar adaptations in other regions with varying epidemiological profiles of periodontal disease. The CDC/AAP classification was strategically developed for surveillance and population‐based research. This definition, which was updated in 2012, 23 has been widely used and accepted as a standard case definition in epidemiological studies. In 2018, the European Federation of Periodontology and AAP (EFP/AAP) introduced a new periodontal classification. 24 The EFP/AAP 2018 case definitions incorporate new knowledge, allowing the identification of clearer clinical entities. The two definitions show high agreement in diagnosing severe periodontitis. 25 However, discrepancies in the prevalence of periodontitis between the two classifications have been noted when using epidemiological data. 26 , 27
The CDC/AAP questionnaire has not been translated into Thai or validated in the Thai population. Therefore, this study aimed to assess the validity of the CDC/AAP self‐report questionnaire 14 for evaluating periodontal status in a Thai adult population, using two periodontal classifications derived from a full‐mouth periodontal examination as the reference standard.
2. MATERIALS AND METHODS
2.1. Study design and population
This cross‐sectional analytical study was conducted between March and July 2023, involving participants aged ≥20 years residing in Chiang Mai, Thailand. Participants were required to read, understand, and respond to questions in Thai and to agree to undergo a clinical periodontal examination. The following exclusion criteria were considered when enrolling participants into the study: fewer than 10 teeth, the presence of a disease or condition contraindicating or requiring antibiotics prior to clinical examination, bleeding disorders, use of medications that increase bleeding risk, and pregnancy or breastfeeding.
2.2. Sampling procedures and sample size
The Statulator, online sample size calculator, was used to determine the sample size for estimating a single proportion, 28 based on the prevalence of moderate and severe periodontitis reported in a previous Thai population study (81.5%). 29 The study required at least 237 participants with 5% absolute precision and a 95% confidence interval. A proportional stratified random sampling technique was used to ensure that the sample reflected the age distribution of the Chiang Mai city population. Participants were recruited through three Subdistrict Health Promotion Hospitals in Chiang Mai, Thailand.
2.3. Ethical considerations
The study protocol was approved by the Human Experimentation Committee of the Faculty of Dentistry, Chiang Mai University, Thailand. (Approval No. 50/2022; October 10, 2022). All participants signed a consent form before inclusion.
2.4. Development of Thai version of self‑report questionnaire
Eight self‐reported questions from CDC/AAP (original English version [EV]) served as the foundation. Translation and adaptation were performed as described in the previous study. 30
Stage 1 Forward Translation: EV was translated into Thai by two independent native Thai speakers: a certified translator (T1) and a dentist (T2).
Stage 2 Synthesis: Thai version (T1‐2) was created by comparing and combining the two translated versions.
Stage 3 Back Translation: An independent native English‐speaking certified translator back‐translated T1‐2 from Thai into English to create the E1 version.
Stage 4 Review: To ensure that the E1 version reflected the same content as the original EV version, we revised and constructed a final Thai version.
Stage 5 Pilot Testing: Thai version was pretested to assess the clarity and comprehension of the questions using test‐retest reliability methods (McNemar test).
Complete set of questionnaires comprised three parts: Part 1 demographic data and medical conditions, Part 2 included CDC/AAP 8‐item questionnaire in Thai, and Part 3 included behavioral factors, previous dental history, and signs and symptoms of periodontal disease.
2.5. Data collection procedures
After signing the consent form, the participants completed self‐administered questionnaires. At the same appointment, a full‐mouth periodontal examination was conducted by a dentist who was blinded to the questionnaire responses. A periodontal probe (PCP‐UNC 15)* was used to measure gingival recession and probing depth (PD) to the nearest millimeter at six sites per tooth, excluding third molars and retained roots. Clinical attachment loss (CAL) was calculated. The amount of supragingival plaque accumulation and the degree of gingival inflammation, assessed by the presence of bleeding on probing, were recorded as plaque index (PI) 31 and gingival index (GI). 32 The number of remaining teeth, presence of dentures, and oral hygiene behavior were also recorded.
Education level was divided into elementary, secondary, or at least a bachelor's degree. Income was classified as low or high based on the mean income of the Thai population in 2022, as reported by the Office of the National Economic and Social Development Council, which was approximately 586.71 USD (20,100 Baht) per month. 33 Body mass index was categorized as underweight, normal, and overweight. 34 GI scores were grouped into mild, moderate, and severe inflammation. PI scores were assigned as excellent, good, fair, and poor. 35
For the CDC/AAP questions, the answers were dichotomized as “yes” and “no,” or “good” and “poor,” according to Eke et al. 8 If the response rate for “Refused” and “Don't know” did not exceed 5%, both were excluded. Otherwise, they were grouped into “yes/poor” or “no/good” categories based on directions of the association toward periodontitis. 36
2.6. Periodontal disease case definition
From full‐mouth records, periodontitis diagnosis was determined using CDC/AAP 2012 23 and the EFP/AAP 2018 24 case definitions.
According to CDC/AAP 2012 23 case definition, severe periodontitis indicated those teeth with ≥2 interproximal sites with CAL ≥ 6 mm and ≥1 interproximal site with PD ≥ 5 mm; moderate periodontitis was those with ≥2 interproximal sites with CAL ≥ 4 mm, or ≥2 interproximal sites with PD ≥ 5 mm; and mild periodontitis was those with ≥2 interproximal sites with CAL ≥ 3 mm and ≥2 interproximal sites with PD ≥ 4 mm, or one site with PD ≥ 5 mm. Participants were assigned to the non‐periodontitis group if there was no evidence of periodontitis.
According to EFP/AAP 2018 24 case definition, periodontitis was diagnosed when interproximal CAL was detected in ≥2 non‐adjacent teeth, or CAL in the buccal or lingual ≥ 3 mm with PD > 3 mm in ≥2 teeth. The severity and complexity of disease management were classified into four stages 37 : stage I was defined as the greatest interproximal CAL of 1–2 mm with maximum PD ≤ 4 mm, stage II was the greatest interproximal CAL of 3–4 mm with PD ≤ 5 mm, and stages III and IV (severe) were defined as having the highest interproximal CAL ≥ 5 mm with PD ≥ 6 mm. Stages III and IV were further differentiated based on complexity factors.
2.7. Statistical analysis
Demographic data are presented as means and standard deviations, medians and ranges, or frequencies and percentages, depending on data distribution. Associations between questionnaire responses and CDC/AAP‐defined or EFP/AAP‐defined periodontitis diagnoses were analyzed using logistic regression models.
Five predictive models were developed (see Table S2 in online Journal of Periodontology):
Model 1 included only the eight CDC/AAP questions.
Model 2 included selected demographic variables and periodontal risk factors.
Model 3 included selected signs and symptoms.
Model 4 was a full model that included CDC/AAP questions and all selected variables from Models 2 and 3.
Model 5 was a reduced model constructed using stepwise regression, which included only relevant and statistically significant variables.
Variables for Models 2 and 3 were selected based on their significant associations (p < 0.05) with at least one periodontal disease case definition in univariable analysis.
Odds ratios are reported with 95% confidence intervals. The validity and reliability of the questionnaires, compared with the case definitions, were evaluated using receiver operating characteristic (ROC) curves, area under the ROC curves (AUCs), sensitivity, and specificity. A p‐value of < 0.05 was considered statistically significant. All analyses were performed using Stata version 14.0.†
3. RESULTS
3.1. Participant characteristics
This study included 250 participants: 80 males (32.0%) and 170 females (68.0%), with ages ranging from 20–82 years (mean, 45.8 ± 16.23 years). Most participants had at least a bachelor's degree (n = 120, 48.0%), and the average monthly income was 417.58 USD (14,305.87 Baht),‡ with the majority earning less than the national average (82%).
3.2. Periodontal status and oral health behaviors
Table 1 presents the demographics, oral health behaviors, and periodontal status of the participants according to each periodontal disease case definition.
TABLE 1.
Demographic data according to periodontal definition.
|
Total n (%) |
CDC/AAP 2012 | EFP/AAP 2018 | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
|
No n (%) |
Mild n (%) |
Moderate n (%) |
Severe n (%) |
Gingivitis n (%) |
Stage I/II n (%) |
Stage III n (%) |
Stage IV n (%) |
||||
| Variables | n = 250 | n = 41 | n = 33 | n = 99 | n = 77 | p * | n = 37 | n = 65 | n = 105 | n = 43 | p * |
| Sex | 0.470 | 0.223 | |||||||||
| Male | 80 (32.0) | 17 (41.5) | 11 (33.3) | 31 (31.3) | 21 (27.3) | 16 (43.2) | 18 (27.7) | 36 (34.3) | 10 (23.3) | ||
| Female | 170 (68.0) | 24 (58.5) | 22 (66.7) | 68 (68.7) | 56 (68.0) | 21 (56.8) | 47 (72.3) | 69 (65.7) | 33 (76.7) | ||
|
Age Mean (SD, range) 45.816 (16.23, 20–82) |
<0.001 | <0.001 | |||||||||
| <35 | 80 (32.0) | 27 (65.9) | 19 (57.6) | 31 (31.3) | 3 (3.9) | 23 (62.2) | 39 (60.0) | 16 (15.2) | 2 (4.7) | ||
| 36–60 | 112 (44.8) | 13 (31.7) | 11 (33.3) | 48 (48.5) | 40 (51.9) | 13 (35.1) | 23 (35.4) | 56 (53.3) | 20 (46.5) | ||
| >61 | 58 (23.2) | 1 (2.4) | 3 (9.1) | 20 (20.2) | 34 (44.2) | 1 (2.7) | 3 (4.6) | 33 (31.4) | 21 (48.8) | ||
| Education level | <0.001 | <0.001 | |||||||||
| <Elementary | 53 (21.2) | 0 (0.0) | 3 (9.1) | 20 (20.2) | 30 (39.0) | 0 (0.0) | 5 (7.7) | 28 (26.7) | 20 (46.5) | ||
| Secondary | 77 (30.8) | 8 (19.5) | 7 (21.2) | 37 (37.4) | 25 (32.5) | 7 (18.9) | 18 (27.7) | 39 (37.1) | 13 (30.2) | ||
| >Bachelor | 120 (48.0) | 33 (80.5) | 23 (69.7) | 42 (42.4) | 22 (28.6) | 30 (81.1) | 42 (64.6) | 38 (36.2) | 10 (23.3) | ||
| Occupation | <0.001 | <0.001 | |||||||||
| Labor | 27 (10.8) | 0 (0.0) | 3 (9.1) | 15 (15.2) | 9 (11.7) | 0 (0.0) | 5 (7.7) | 16 (15.2) | 6 (14.0) | ||
| Private employee | 72 (28.8) | 7 (17.1) | 3 (9.1) | 36 (36.4) | 26 (33.8) | 6 (16.2) | 14 (21.5) | 40 (38.1) | 12 (27.9) | ||
| Governmental employee | 64 (25.6) | 21 (51.2) | 14 (42.4) | 18 (18.2) | 11 (14.3) | 19 (51.4) | 27 (41.5) | 14 (13.3) | 64 (25.6) | ||
| Unemployed | 87 (34.8) | 13 (39.4) | 13 (39.4) | 30 (30.3) | 31 (40.3) | 12 (32.4) | 19 (29.2) | 35 (33.3) | 87 (34.8) | ||
|
Income Mean 417.58 USD |
0.043 | 0.028 | |||||||||
| <586.71 USD | 205 (82.0) | 28 (68.3) | 25 (75.8) | 86 (86.9) | 66 (85.7) | 25 (67.6) | 52 (80.0) | 88 (83.8) | 40 (93.0) | ||
| >586.71 USD | 45 (18.0) | 13 (31.7) | 8 (24.2) | 13 (13.1) | 11 (14.3) | 12 (32.4) | 13 (20.0) | 17 (16.2) | 3 (7.0) | ||
| Diabetes | 0.296 | 0.497 | |||||||||
| Yes | 13 (5.2) | 0 (0.0) | 1 (3.0) | 6 (6.1) | 6 (7.8) | 0 (0.0) | 4 (6.2) | 6 (5.7) | 3 (7.0) | ||
| No | 237 (94.8) | 41 (100) | 32 (97.0) | 93 (93.9) | 71 (92.2) | 37 (100.0) | 61 (93.8) | 99 (94.3) | 40 (93.0) | ||
| Smoking | 0.187 | 0.331 | |||||||||
| Non‐smoker | 205 (82.0) | 34 (82.9) | 26 (78.8) | 86 (86.9) | 59 (76.6) | 31 (83.8) | 54 (83.1) | 85 (81.0) | 35 (81.4) | ||
| Former | 31 (12.4) | 4 (9.8) | 3 (9.1) | 10 (10.1) | 14 (18.2) | 4 (10.8) | 5 (7.7) | 17 (16.2) | 5 (11.6) | ||
| Current | 11 (4.4) | 2 (4.9) | 2 (6.1) | 3 (3.0) | 4 (5.2) | 2 (5.4) | 3 (4.6) | 3 (2.9) | 3 (7.0) | ||
| E‐cigarettes | 3 (1.2) | 1 (2.4) | 2 (6.1) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 3 (4.6) | 0 (0.0) | 0 (0.0) | ||
|
BMI Mean (SD, range) 24.95 (5.50, 13.13–66.41) |
0.020 | 0.176 | |||||||||
| <18.50 | 15 (6.0) | 3 (7.3) | 7 (21.2) | 3 (3.0) | 2 (2.6) | 3 (8.1) | 8 (12.3) | 4 (3.8) | 0 (0.0) | ||
| 18.50–22.90 | 81 (32.4) | 12 (29.3) | 12 (36.4) | 31 (31.3) | 26 (33.8) | 11 (28.7) | 20 (30.8) | 37 (35.2) | 13 (30.2) | ||
| >23 | 154 (61.6) | 26 (63.4) | 14 (42.4) | 65 (65.7) | 49 (63.6) | 23 (62.2) | 37 (56.9) | 64 (61.0) | 30 (69.8) | ||
| PD, mean (SD) | 2.72 (0.42) | 2.41 (0.17) | 2.45 (0.16) | 2.65 (0.22) | 3.10 (0.51) | <0.001 | 2.41 (0.18) | 2.52 (0.19) | 2.79 (0.35) | 3.13 (0.58) | <0.001 |
| CAL, mean (SD) | 2.87 (0.84) | 2.14 (0.23) | 2.25 (0.27) | 2.71 (0.29) | 3.74 (0.96) | <0.001 | 2.14 (0.24) | 2.31 (0.24) | 3.07 (0.64) | 3.85 (1.03) | <0.001 |
|
Remaining teeth mean (SD) |
25.56 (2.88) | 26.37 (1.87) | 26.58 (1.73) | 25.84 (2.34) | 24.34 (3.83) | 0.003 | 26.41 (1.85) | 26.57 (1.70) | 26.04 (2.00) | 22.14 (4.16) | <0.001 |
| GI, mean (SD) | 1.14 (0.44) | 0.82 (0.27) | 0.88 (0.40) | 1.16 (0.41) | 1.39 (0.39) | <0.001 | 0.80 (0.27) | 1.00 (0.42) | 1.22 (0.41) | 1.44 (0.38) | <0.001 |
| Mild gingivitis | 124 (49.6) | 37 (90.2) | 25 (75.8) | 43 (43.4) | 19 (24.7) | 34 (91.9) | 43 (66.2) | 37 (35.2) | 10 (23.3) | ||
| Moderate gingivitis | 125 (50.0) | 4 (9.8) | 8 (24.2) | 55 (55.6) | 58 (75.3) | 3 (8.1) | 21 (32.3) | 68 (64.8) | 33 (76.7) | ||
| Severe gingivitis | 1 (0.4) | 0 (0.0) | 0 (0.0) | 1 (1.0) | 0 (0.0) | 0 (0.0) | 1 (1.5) | 0 (0.0) | 0 (0.0) | ||
| PI, mean (SD) | 0.75 (0.33) | 0.55 (0.25) | 0.68 (0.31) | 0.80 (0.30) | 0.83 (0.36) | 0.002 | 0.54 (0.25) | 0.73 (0.30) | 0.78 (0.32) | 0.89 (0.38) | 0.001 |
| Good | 193 (77.2) | 39 (95.1) | 28 (84.8) | 74 (74.7) | 52 (67.5) | 35 (94.6) | 54 (83.1) | 78 (74.3) | 26 (60.5) | ||
| Fair, poor | 57 (22.8) | 2 (4.9) | 5 (15.2) | 25 (25.3) | 25 (32.5) | 2 (5.4) | 11 (16.9) | 27 (25.7) | 17 (39.5) | ||
| Dental frequency | 0.040 | 0.023 | |||||||||
| At least 1 per year | 106 (42.4) | 23 (56.1) | 17 (51.5) | 42 (42.4) | 24 (31.2) | 20 (54.1) | 35 (53.8) | 35 (33.3) | 16 (37.2) | ||
| Less than 1 per year | 144 (57.6) | 18 (43.9) | 16 (48.5) | 57 (57.6) | 53 (68.8) | 17 (45.9) | 30 (46.2) | 70 (66.7) | 27 (62.8) | ||
| Brushing frequency | 0.928 | 0.979 | |||||||||
| Sometimes, once per day | 9 (3.6) | 1 (2.4) | 2 (6.1) | 3 (3.0) | 3 (3.9) | 1 (2.7) | 2 (3.1) | 4 (3.8) | 2 (4.7) | ||
| Twice per day | 200 (80.0) | 33 (80.5) | 24 (72.7) | 81 (81.8) | 62 (80.5) | 30 (81.1) | 51 (78.5) | 83 (79.0) | 36 (83.7) | ||
| More than twice per day | 41 (16.4) | 7 (17.1) | 7 (21.2) | 15 (15.2) | 12 (15.6) | 6 (16.2) | 12 (18.5) | 5 (11.6) | 5 (11.6) | ||
Abbreviations: BMI, body mass index; CAL, clinical attachment loss; GI, gingival index; PD, probing depth; PI, plaque index; USD, United States dollar.
p < 0.05.
The mean number of remaining teeth was 25.56 ± 2.88 per person. Mean PD and CAL were 2.72 ± 0.42 mm and 2.87 ± 0.84 mm, respectively. The mean GI was 1.14 ± 0.44, and the mean PI was 0.75 ± 0.33, with most participants (77.2%) having a PI < 1.0. However, approximately 40% of participants visited the dentist at least once a year, with the remainder either never consulting or only seeking care when experiencing symptoms.
Based on CDC/AAP case definitions, 77 participants (30.8%) had severe periodontitis, 99 (39.6%) had moderate periodontitis, and 33 (13.2%) had mild periodontitis. According to the EFP/AAP case definition, 43 participants (17.2%) were diagnosed with stage IV periodontitis, 105 (42.0%) with stage III periodontitis, 65 (26%) with stage II periodontitis, and 37 (14.8%) with gingivitis.
Regarding known risk factors for periodontitis, 5.2% of participants were diagnosed with diabetes mellitus (DM), and 5.6% reported being current smokers.
3.3. Self‐reported questionnaires
Reliability testing of the Thai version of the CDC/AAP questionnaire and its related answer choices revealed no significant differences in test‐retest reliability. (McNemar test; p = 0.05–1.00). These findings demonstrated that the questionnaires provided consistent results over time, indicating the understandability of the translated questions.
3.4. Responses to self‐reported questionnaires by periodontal disease case definitions
Table 2 shows the frequency of questionnaire responses categorized according to periodontal status. The response rate was 100%, with <1% responding “Refused.” For question 1, over half of the participants answered, “Don't Know,” whereas questions 2, 4, and 6 had approximately 5%–10% “Don't Know” responses. Interestingly, question 3 revealed that most participants (n = 227, 90.8%) had never undergone root planing procedures, but 68.3% (n = 155) had undergone at least one visit for scaling.
TABLE 2.
CDC Questionnaires response rate according to periodontal definition.
|
Question and response |
Total n (%) |
CDC/AAP 2012 | EFP/AAP 2018 | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
|
No n (%) |
Mild n (%) |
Moderate n (%) |
Severe n (%) |
Gingivitis n (%) |
Stage I/II n (%) |
Stage III n (%) |
Stage IV n (%) |
||||
| n = 250 | n = 41 | n = 33 | n = 99 | n = 77 | p * | n = 37 | n = 65 | n = 105 | n = 43 | p * | |
| Q1. Do you think you might have gum disease? | |||||||||||
| 0.020 | 0.040 | ||||||||||
| Yes | 59 (23.6) | 4 (9.8) | 7 (21.2) | 19 (19.2) | 29 (37.7) | 4 (10.8) | 14 (21.5) | 31 (29.5) | 10 (23.3) | ||
| No | 59 (23.6) | 9 (22.0) | 6 (18.2) | 26 (26.3) | 18 (23.4) | 9 (24.3) | 9 (13.8) | 28 (26.7) | 13 (30.2) | ||
| Don't know | 130 (52.0) | 28 (68.3) | 20 (60.6) | 53 (53.5) | 29 (37.7) | 24 (64.9) | 42 (64.6) | 45 (42.9) | 19 (44.2) | ||
| Refused | 2 (0.8) | 0 (0.0) | 0 (0.0) | 1 (1.0) | 1 (1.0) | 0 (0.0) | 0 (0.0) | 1 (1.0) | 1 (2.3) | ||
| Q2. Overall, how would you rate the health of your teeth and gums? | |||||||||||
| N/A | N/A | ||||||||||
| Excellent | 6 (2.4) | 0 (0.0) | 1 (3.0) | 2 (2.0) | 3 (3.9) | 0 (0.0) | 1 (1.5) | 4 (3.8) | 1 (2.3) | ||
| Very good | 14 (5.6) | 6 (14.6) | 1 (3.0) | 4 (4.0) | 3 (3.9) | 6 (16.2) | 3 (4.6) | 4 (3.8) | 1 (2.3) | ||
| Good | 52 (20.8) | 6 (16.6) | 10 (30.3) | 19 (19.2) | 17 (22.1) | 4 (10.8) | 15 (23.1) | 24 (22.9) | 9 (20.9) | ||
| Fair | 133 (53.2) | 28 (68.3) | 17 (51.5) | 53 (53.5) | 35 (45.5) | 26 (70.3) | 37 (56.9) | 51 (48.6) | 19 (44.2) | ||
| Poor | 30 (12.0) | 1 (2.4) | 3 (9.1) | 13 (13.1) | 13 (16.9) | 1 (2.7) | 6 (9.2) | 15 (14.3) | 8 (18.6) | ||
| Don't know | 13 (5.2) | 0 (0.0) | 1 (3.0) | 6 (6.1) | 6 (7.8) | 0 (0.0) | 3 (4.6) | 6 (5.7) | 4 (9.3) | ||
| Refused | 2 (0.8) | 0 (0.0) | 0 (0.0) | 2 (2.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 1 (1.0) | 1 (2.3) | ||
| Q3. Have you ever had treatment for gum disease, such as scaling and root planing, sometimes called ‘deep’ cleaning? | |||||||||||
| 0.538 | 0.314 | ||||||||||
| Yes | 21 (8.4) | 6 (14.6) | 3 (9.1) | 6 (6.1) | 6 (6.1) | 5 (13.5) | 6 (9.2) | 8 (7.6) | 2 (4.7) | ||
| No | 72 (28.8) | 8 (19.5) | 8 (24.2) | 31 (31.3) | 25 (32.5) | 8 (21.6) | 15 (23.1) | 38 (36.2) | 11 (25.6) | ||
| Don't know | 1 (0.4) | 0 (0.0) | 0 (0.0) | 1 (1.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 1 (1.0) | 0 (0.0) | ||
| Refused | 1 (0.4) | 1 (2.4) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 1 (2.7) | 0 (0.0) | 0 (0.0) | 0 (0.0) | ||
| Scaling only | 155 (62.0) | 26 (63.4) | 22 (66.7) | 61 (61.6) | 46 (59.7) | 23 (62.2) | 44 (67.7) | 58 (55.2) | 30 (69.8) | ||
| Q4. Have you ever had any teeth become loose on their own, without an injury? | |||||||||||
| <0.001 | <0.001 | ||||||||||
| Yes | 59 (23.6) | 5 (12.2) | 2 (6.1) | 16 (16.2) | 36 (46.8) | 5 (13.5) | 4 (6.2) | 30 (28.6) | 20 (46.5) | ||
| No | 162 (64.8) | 32 (78.0) | 27 (81.8) | 70 (70.7) | 33 (42.9) | 30 (81.1) | 53 (81.5) | 61 (58.1) | 18 (41.9) | ||
| Don't know | 27 (10.8) | 4 (9.8) | 4 (12.1) | 13 (13.1) | 6 (7.8) | 2 (5.4) | 8 (12.3) | 14 (13.3) | 3 (7.0) | ||
| Refused | 2 (0.8) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 2 (2.6) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 2 (4.7) | ||
| Q5. Have you ever been told by a dental professional that you lost bone around your teeth? | |||||||||||
| 0.458 | 0.557 | ||||||||||
| Yes | 17 (6.8) | 2 (4.9) | 0 (0.0) | 8 (8.1) | 7 (9.1) | 2 (5.4) | 2 (3.1) | 11 (10.5) | 2 (4.7) | ||
| No | 222 (88.8) | 38 (92.7) | 30 (90.9) | 88 (88.9) | 66 (85.7) | 34 (91.9) | 60 (92.3) | 90 (85.7) | 38 (88.4) | ||
| Don't know | 10 (4.0) | 1 (2.4) | 3 (9.1) | 3 (3.0) | 3 (3.9) | 1 (2.7) | 3 (4.6) | 4 (3.8) | 2 (4.7) | ||
| Refused | 1 (0.4) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 1 (1.3) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 1 (2.3) | ||
| Q6. During the past 3 months, have you noticed a tooth that doesn't look right? | |||||||||||
| 0.009 | 0.446 | ||||||||||
| Yes | 104 (41.6) | 12 (29.3) | 10 (30.3) | 37 (37.4) | 45 (58.4) | 12 (32.4) | 23 (35.4) | 46 (43.8) | 23 (53.5) | ||
| No | 111 (44.4) | 23 (56.1) | 15 (45.5) | 46 (46.5) | 27 (35.1) | 20 (54.1) | 30 (46.2) | 46 (43.8) | 15 (34.9) | ||
| Don't know | 35 (14.0) | 6 (14.6) | 8 (24.2) | 16 (16.2) | 5 (6.5) | 5 (13.5) | 12 (18.5) | 13 (12.4) | 5 (11.6) | ||
| Refused | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | ||
| Q7. In the last 7 days, how many times did you use dental floss or any other device to clean between your teeth? | |||||||||||
| 0.919 | 0.754 | ||||||||||
| Use | 155 (62.0) | 25 (61.0) | 22 (66.7) | 62 (62.6) | 46 (59.7) | 22 (59.5) | 44 (67.7) | 63 (60.0) | 26 (60.5) | ||
| Not use | 95 (38.0) | 16 (39.0) | 11 (33.3) | 37 (37.4) | 31 (40.3) | 15 (40.5) | 21 (32.3) | 42 (40.0) | 17 (39.5) | ||
| Q8. In the last 7 days, how many times did you use mouthwash or other dental rinse products that you use to treat dental disease or dental problems? | |||||||||||
| 0.053 | 0.087 | ||||||||||
| Use | 109 (43.6) | 11 (26.8) | 14 (42.4) | 43 (43.4) | 41 (53.2) | 11 (29.7) | 28 (43.1) | 45 (42.9) | 25 (58.1) | ||
| Not use | 141 (56.4) | 30 (73.2) | 19 (57.6) | 56 (56.6) | 36 (46.8) | 26 (70.3) | 37 (56.9) | 60 (57.1) | 18 (41.9) | ||
Abbreviation: N/A, not applicable.
p < 0.05.
The correlation between responses and periodontal disease case definitions is presented in Table 3. Question 4 was highly associated with CDC/AAP‐defined moderate/severe periodontitis and severe periodontitis, and EFP/AAP‐defined stages III and IV periodontitis (p ≤ 0.001). Questions 1, 6, and 8 were significantly associated with CDC/AAP‐defined moderate/severe and severe periodontitis.
TABLE 3.
The univariate association (crude odds ratio, 95%CI) between individual questions from the CDC/AAP questionnaire with periodontal disease.
| CDC/AAP 2012 | EFP/AAP 2018 | ||
|---|---|---|---|
| Variables | Moderate and severe periodontitis | Severe periodontitis | Stage III and IV |
| CDC questions | |||
| Q1) Do you think you might have gum disease? (have gum disease) | |||
| Yes (1) | 2.18 (1.06‐4.49)* | 2.92 (1.59‐5.36)* | 1.82 (0.98‐3.40) |
| No (0) | 1.00 | 1.00 | 1.00 |
| Don't know (0) | |||
| Refused | |||
| Q2) Overall, how would you rate the health of your teeth and gums? | |||
| Excellent (0) | 1.00 | 1.00 | 1.00 |
| Very good (0) | |||
| Good (0) | |||
| Fair (1) | 1.26 (0.70‐2.27) | 0.94 (0.52‐1.70) | 0.95 (0.54‐1.66) |
| Poor (1) | |||
| Don't know (1) | |||
| Refused | |||
| Q3) Have you ever had treatment for gum disease, such as scaling and root planing, sometimes called ‘‘deep’’ cleaning? | |||
| Yes (1) | 0.52 (0.21‐1.30) | 0.88 (0.33‐2.36) | 0.60 (0.24‐1.46) |
| No & Scaling only (0) | 1.00 | 1.00 | 1.00 |
| Don't know | |||
| Refused | |||
| Q4) Have you ever had any teeth become loose on their own, without an injury? | |||
| Yes (1) | 4.08 (1.76‐9.48)* | 6.02 (3.20‐11.31)* | 5.38 (2.50‐11.56)* |
| No (0) | 1.00 | 1.00 | 1.00 |
| Don't know (0) | |||
| Refused | |||
| Q5) Have you ever been told by a dental professional that you lost bone around your teeth? | |||
| Yes (1) | 3.31 (0.74‐14.88) | 1.65 (0.60‐4.53) | 2.39 (0.75‐7.55) |
| No (0) | 1.00 | 1.00 | 1.00 |
| Don't know | |||
| Refused | |||
| Q6) During the past 3 months, have you noticed a tooth that doesn't look right? | |||
| Yes (1) | 2.06 (1.15‐3.68)* | 2.72 (1.57‐4.72)* | 1.67 (0.99‐2.81) |
| No (0) | 1.00 | 1.00 | 1.00 |
| Don't know (0) | |||
| Refused | |||
| Q7) In the last 7 days, how many times did you use dental floss or any other device to clean between your teeth? | |||
| Use (0) | 1.00 | 1.00 | 1.00 |
| Not use (1) | 1.10 (0.62‐1.92) | 1.15 (0.66‐1.99) | 1.22 (0.72‐2.05) |
| Q8) In the last 7 days, how many times did you use mouthwash or other dental rinse product that you use to treat dental disease or dental problems? | |||
| Use (1) | 1.79 (1.02‐3.15)* | 1.76 (1.02‐3.02)* | 1.45 (0.87‐2.42) |
| Not use (0) | 1.00 | 1.00 | 1.00 |
p < 0.05.
Other variables that showed an association with all periodontal disease case definitions tested were age, education level, occupation, PI, notice of spacing, pain, and dental visits frequency (Table 4).
TABLE 4.
The univariate association (crude odds ratio, 95% CI) between other demographics questions with periodontal disease.
| CDC/AAP 2012 | EFP/AAP 2018 | ||
|---|---|---|---|
| Variables | Moderate and severe periodontitis | Severe periodontitis | Stages III and IV |
| Sex | |||
| Male (1) | 00.69 (0.39–1.22) | 0.72 (0.40–1.31) | 0.90 (0.53–1.55) |
| Female (0) | 1.00 | 1.00 | 1.00 |
| Age | |||
| <35 (0) | 1.00 | 1.00 | 1.00 |
| 36–60 (1) | 4.96 (2.64–9.34) * | 14.26 (4.22–48.13) * | 7.27 (3.77–14.04) * |
| >60 (2) | 18.26 (6.03–55.32) * | 36.36 (10.25–128.99) * | 46.50 (14.82–145.86) * |
| Education level | |||
| ≤Elementary (1) | 14.58 (4.31–49.35) * | 5.81 (2.85–11.86) * | 14.40 (5.35–38.79) * |
| Secondary (2) | 3.62 (1.85–4.06) * | 2.14 (1.10–4.16) * | 3.12 (1.71–5.69) * |
| Bachelor (0) | 1.00 | 1.00 | 1.00 |
| Occupation | |||
| Labor (1) | 9.66 (2.64–35.33) * | 2.41 (0.86–6.75) | 11.24 (3.69–34.24) * |
| Private employee (2) | 7.48 (3.26–17.15) * | 2.72 (1.21–6.11) * | 6.64 (3.14–14.07) * |
| Governmental employee (0) | 1.00 | 1.00 | 1.00 |
| Unemployed (3) | 2.83 (1.44–5.55) * | 2.67 (1.22–5.8) * | 4.62 (2.29–9.29) * |
| Income | |||
| <586.71 USD (1) | 2.51 (1.29–4.87) * | 1.47 (0.70–3.08) | 2.08 (1.08–3.99) * |
| >586.71 USD (0) | 1.00 | 1.00 | 1.00 |
| Diabetes | |||
| Yes (1) | 5.34 (0.68–41.85) | 2.00 (0.65–6.17) | 1.59 (0.48–5.30) |
| No (0) | 1.00 | 1.00 | 1.00 |
| Smoking status | |||
| Non (0) | 1.00 | 1.00 | 1.00 |
| Smoker (1) | 0.92 (0.46–1.84) | 1.65 (0.85–3.22) | 1.17 (0.60–2.27) |
| BMI | |||
| <18.50 (1) | 0.21 (0.07–0.68) * | 0.33 (0.07–1.55) | 0.23 (0.07–0.77) * |
| 18.50–22.90 (0) | 1.00 | 1.00 | 1.00 |
| >23 (2) | 1.20 (0.66–2.18) | 0.99 (0.55–1.76) | 0.97 (0.56–1.69) |
| PI | |||
| Good (0) | 1.00 | 1.00 | 1.00 |
| Fair/Poor (1) | 3.80 (1.63–8.84) * | 2.12 (1.15–3.91) * | 2.90 (1.47–5.72) * |
| Inflammation | |||
| Yes (1) | 2.76 (1.32–5.78) * | 1.71 (0.94–3.10) | 2.04 (1.10–3.78) * |
| No (0) | 1.00 | 1.00 | 1.00 |
| Spacing | |||
| Yes (1) | 2.18 (1.16–4.09) * | 2.63 (1.50–4.61) * | 1.78 (1.02–3.10) * |
| No (0) | 1.00 | 1.00 | 1.00 |
| Pain | |||
| Yes (1) | 2.42 (1.18–4.96) * | 2.45 (1.35–4.44) * | 2.28 (1.22–4.26) * |
| No (0) | 1.00 | 1.00 | 1.00 |
| Dentist frequency visits | |||
| Less than 1 per year (1) | 1.96 (1.13–3.40) * | 1.99 (1.13–3.51) * | 2.23 (1.33–3.73) * |
| At least 1 per year (0) | 1.00 | 1.00 | 1.00 |
Abbreviations: BMI, body mass index; PI, plaque index; USD, United States dollar.
p < 0.05.
3.5. Predictive abilities of the questionnaires
CDC/AAP self‐reported questions (Model 1) showed satisfactory performance in predicting CDC/AAP‐defined moderate/severe periodontitis and severe periodontitis and EFP/AAP‐defined stage III/IV periodontitis, with AUCs of 0.70, 0.74, and 0.69, respectively. Performance improved when selected demographic variables and periodontal risk factors were added (Model 2), with AUCs of 0.84, 0.86, and 0.88, respectively (Table 5). However, adding sign‐ and symptom‐related questions (Model 3) did not significantly improve the predictive ability (p > 0.05). Model 4 or the full model, which included all questions, did not significantly improve performance compared with Model 2 (p > 0.05).
TABLE 5.
Multivariable logistic regression analysis (95% CI).
| CDC/AAP 2012 | EFP/AAP 2018 | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Moderate and severe periodontitis | Severe periodontitis | Stages III and IV | |||||||||||||
| Model 1 | Model 2 | Model 3 | Model 4 | Model 5 | Model 1 | Model 2 | Model 3 | Model 4 | Model 5 | Model 1 | Model 2 | Model 3 | Model 4 | Model 5 | |
| CDC/AAP questions | |||||||||||||||
| Q1 | 1.73 (0.74–4.07) | 1.56 (0.60–4.02) | 1.55 (0.60–3.98) | 1.32 (0.47–3.72) | 2.46 * (1.18–5.15) | 2.32 (1.00–5.38) | 2.86 * (1.28–6.43) | 2.52 * (1.01–6.28) | 1.51 (0.71–3.18) | 1.45 (0.58–3.63) | 1.51 (0.66–3.47) | 1.26 (0.47–3.36) | |||
| Q2 | 0.88 (0.46–1.69) | 1.03 (0.47–2.28) | 0.76 (0.38–1.50) | 0.90 (0.39–2.04) | 0.48 * (0.23–0.97) | 0.58 (0.25–1.33) | 0.42 * (0.20–0.87) | 0.55 (0.23–1.29) | 1.59 (0.85–2.97) | 0.66 (0.29–1.51) | 0.53 (0.27–1.02) | 0.55 (0.23–1.32) | |||
| Q3 | 0.25 * (0.08–0.78) | 0.19 * (0.05–0.75) | 0.20 * (0.06–0.70) | 0.14 * (0.03–0.62) | 0.27 * (0.09–0.85) | 0.45 (0.13–1.56) | 0.46 (0.11–1.82) | 0.48 (0.13–1.78) | 0.39 (0.09–1.71) | 2.98 (0.98–9.10) | 0.16 * (0.04–0.67) | 0.27 * (0.08–0.94) | 0.10 * (0.02–0.51) | 0.15 * (0.04–0.53) | |
| Q4 | 2.85 * (1.11–7.30) | 1.79 (0.60–5.37) | 2.90 * (1.10–7.61) | 1.89 (0.61–5.84) | 4.32 * (2.06–9.07) | 3.01 * (1.26–7.21) | 4.10 * (1.87–9.01) | 2.79 * (1.12–6.96) | 3.72 * (1.80–7.67) | 5.28 * (2.24–12.44) | 4.37 * (1.52–12.56) | 5.61 * (2.30–13.68) | 5.07 * (1.66–15.46) | 3.53 * (1.43–8.75) | |
| Q5 | 4.28 (0.75–24.25) | 2.30 (0.38–13.89) | 6.43 * (1.08–38.43) | 2.90 (0.45–18.70) | 1.77 (0.50–6.29) | 1.41 (0.37–5.36) | 2.02 (0.53–7.78) | 1.23 (0.29–5.25) | 3.19 (0.81–12.41) | 2.34 (0.52–10.63) | 4.92 * (1.18–20.46) | 3.36 (0.68–16.55) | |||
| Q6 | 1.40 (0.69–2.84) | 0.94 (0.39–2.22) | 1.16 (0.54–2.46) | 0.78 (0.32–1.94) | 1.48 (0.72–3.02) | 1.23 (0.54–2.84) | 1.24 (0.58–2.66) | 1.08 (0.45–2.59) | 0.98 (0.51–1.88) | 0.52 (0.22–1.26) | 0.85 (0.42–1.71) | 0.41 (0.16–1.07) | |||
| Q7 | 1.29 (0.68–2.41) | 1.44 (0.68–3.03) | 1.22 (0.63–2.37) | 1.49 (0.68–3.28) | 1.49 (0.78–2.85) | 1.61 (0.76–3.41) | 1.44 (0.72–2.87) | 1.63 (0.74–3.56) | 1.41 (0.79–2.55) | 1.46 (0.69–3.10) | 1.30 (0.69–2.44) | 1.44 (0.65–3.17) | |||
| Q8 | 1.92 * (1.02–3.61) | 1.90 (0.91–3.97) | 1.95 * (1.01–3.79) | 1.85 (0.86–3.95) | 2.19 * (1.09–4.40) | 1.55 (0.83–2.89) | 1.39 (0.69–2.82) | 1.44 (0.75–2.77) | 1.29 (0.62–2.67) | 1.38 (0.78–2.46) | 1.25 (0.61–2.58) | 1.33 (0.73–2.45) | 1.13 (0.54–2.37) | ||
| Demographic variables | |||||||||||||||
| Age (1) | 4.43 * (1.81–10.81) | 4.44 * (1.77–11.12) | 8.37 * (3.88–18.05) | 14.68 * (2.90–74.42) | 13.48 * (2.66–68.30) | 11.90 * (2.64–53.78) | 6.94 * (2.81–17.15) | 6.52 * (2.58–16.47) | 4.64 * (2.16–9.99) | ||||||
| Age (2) | 16.30 * (4.07–65.19) | 13.99 * (3.39–57.83) | 28.32 * (8.11–98.93) | 31.60 * (5.70–175.05) | 32.71 * (5.89–181.72) | 26.19 * (5.46–125.69) | 63.01 * (13.99–283.75) | 56.65 * (12.12–264.88) | 29.57 * (8.14–107.39) | ||||||
| Sex | 0.70 (0.31–1.55) | 0.67 (0.29–1.54) | 0.36 (0.12–1.06) | 0.40 (0.13–1.21) | 1.01 (0.44–2.34) | 0.96 (0.40–2.28) | |||||||||
| Education (1) | 3.15 (0.74–13.32) | 3.82 (0.86–16.99) | 1.86 (0.60–5.74) | 1.91 (0.60–6.09) | 2.52 * (1.08–5.90) | 3.67 * (1.05–12.86) | 4.28 * (1.16–15.87) | 5.95 * (1.91–18.54) | |||||||
| Education (2) | 2.17 (0.91–5.19) | 2.20 (0.90–5.36) | 1.06 (0.39–2.90) | 1.11 (0.40–3.10) | 1.13 (0.51–2.52) | 1.61 (0.68–3.83) | 1.51 (0.62–3.68) | 2.01 (0.96–4.24) | |||||||
| Income | 2.44 (0.95–6.21) | 1.98 (0.75–5.19) | 4.52 * (1.92–10.67) | 1.35 (0.44–4.14) | 1.24 (0.40–3.83) | 2.49 (0.93–6.65) | 1.99 (0.73–5.43) | ||||||||
| Diabetes | 4.12 (0.36–47.05) | 3.59 (0.33–39.05) | 1.24 (0.30–5.07) | 1.13 (0.26–4.99) | 0.38 (0.07–2.06) | 0.34 (0.06–2.00) | |||||||||
| Smoking | 0.80 (0.30–2.16) | 0.83 (0.30–2.29) | 3.34 * (1.03–10.84) | 3.76 * (1.11–12.76) | 0.88 (0.31–2.51) | 0.96 (0.33–2.80) | |||||||||
| Signs and symptoms | |||||||||||||||
| Inflammatory | 1.53 (0.54–2.46) | 2.14 (0.63–7.31) | 0.47 (0.18–1.21) | 0.53 (0.18–1.57) | 0.97 (0.39–2.42) | 1.60 (0.50–5.12) | |||||||||
| Spacing | 1.61 (0.76–3.41) | 1.66 (0.70–3.93) | 1.83 (0.88–3.81) | 1.89 (0.81–4.39) | 1.35 (0.67–2.69) | 1.57 (0.66–3.70) | |||||||||
| Pain | 1.58 (0.62–4.04) | 1.07 (0.34–3.39) | 2.48 * (1.02–6.01) | 2.49 (0.95–6.55) | 2.14 (0.91–5.07) | 1.90 (0.66–5.49) | |||||||||
| Dentist frequency visits | 2.15 * (1.14–4.06) | 1.18 (0.57–2.45) | 1.98 (0.99–3.95) | 1.07 (0.47–2.45) | 2.64 * (1.43‐4.85) | 1.60 (0.75–3.39) | |||||||||
| Diagnostic parameters | |||||||||||||||
| Sensitivity | 98.79 | 84.85 | 92.07 | 88.41 | 88.41 | 43.66 | 60.56 | 43.66 | 57.75 | 57.75 | 73.72 | 83.21 | 78.68 | 83.82 | 79.41 |
| Specificity | 8.70 | 60.87 | 27.54 | 62.32 | 53.62 | 89.57 | 87.73 | 91.98 | 87.04 | 83.95 | 50.52 | 77.32 | 53.61 | 79.38 | 81.44 |
| PPV | 72.12 | 83.83 | 75.12 | 84.80 | 81.92 | 64.58 | 68.25 | 70.45 | 66.13 | 61.19 | 67.79 | 83.82 | 70.39 | 85.07 | 85.71 |
| NPV | 75.00 | 62.69 | 59.38 | 69.35 | 66.07 | 78.49 | 83.63 | 78.84 | 82.46 | 81.93 | 57.65 | 76.53 | 64.20 | 77.78 | 73.83 |
| AUC | 0.697 | 0.843 | 0.744 | 0.860 | 0.822 | 0.737 | 0.859 | 0.761 | 0.866 | 0.825 | 0.693 | 0.877 | 0.752 | 0.888 | 0.859 |
Abbreviations: AUC, area under the receiver operating characteristic curves; NPV, negative predictive value; PPV, positive predictive value.
p < 0.05.
The final reduced model (Model 5) for predicting moderate/severe periodontitis, which included questions 3 and 8, along with age and income, had an AUC of 0.82, sensitivity of 88.4%, and specificity of 53.6%. The reduced model for predicting severe periodontitis, which included questions 4, age, and education level, had an AUC of 0.82, sensitivity of 57.8%, and specificity of 84.0% (Figure 1A,B). The reduced model achieved a level of predictive accuracy comparable with that of the full model (Model 4) (p > 0.05).
FIGURE 1.
Receiver operating characteristics (ROC) curves: (A) ROC curve of model 5 for predicting moderate and severe periodontitis (CDC/AAP 2012) 23 ; (B) ROC curve of model 5 for predicting severe periodontitis (CDC/AAP 2012) 23 ; (C) ROC curve of model 5 for predicting stage III and IV periodontitis (EFP/AAP 2018). 24
To predict “stages III and IV periodontitis,” Model 5 which included questions 3 and 4, together with age and education level, had an AUC 0.86 with a sensitivity 79.4% and specificity 81.4% (Figure 1C). This reduced model achieved a predictive accuracy level comparable with that of the full model (Model 4).
Remarkably, our investigation yielded high specificity but low sensitivity in predicting severe periodontitis and high sensitivity but low specificity in predicting moderate‐to‐severe periodontitis based on the CDC/AAP case definition. In predicting stages III and IV periodontitis using the EFP/AAP case definition, our analysis demonstrated a noteworthy high sensitivity and specificity.
In distinguishing between moderate/periodontitis and no/mild periodontitis, question 3 “Have you ever had treatment for gum disease?” showed significant associations in every model. Question 4 “Have you ever had any teeth become loose on their own?” was the best predictor for severe periodontitis in all models.
4. DISCUSSION
CDC/AAP 2012 and EFP/AAP 2018 case definitions report periodontitis prevalence as 85.2% (n = 213) and 83.6% (n = 209), respectively. According to CDC/AAP definition, 30.8% (n = 77) had severe periodontitis. This was consistent with a prior study in the population of the Electricity Generating Authority of Thailand (EGAT) (n = 5690, age 25–77 years), which found a prevalence of severe periodontitis at 29.6%. 29 However, our results were higher than those reported by the Thai NOHS, 4 which showed a prevalence of severe periodontitis (equivalent to the Community Periodontal Index; CPI = 4 38 ) at 9.2% in the 35–44 year age group and 18.7% in the 60–74 year age group. This difference may be owing to the use of the CPI index, which could result in underestimation. 39 According to the EFP/AAP 2018 classification, 59.2% (n = 148) of participants were categorized as stages III and IV. Although one study suggested that the EFP/AAP 2018 criteria might be less accurate in adults with a high prevalence of periodontitis, 26 other studies demonstrated high agreement between the two classifications when applied in different populations, including those with high prevalence. 25 , 38 Given the varying strengths and sensitivities of these criteria, careful consideration should be given when selecting definitions for use in population‐based studies.
As age has been shown to be associated with disease severity, a proportional stratified sampling method was used to distribute participants by age and decrease the probability of recruiting a disease‐prone population. Furthermore, with a wide age range, we could verify the validity of our questionnaires across different age groups. Regarding reliability, the translated version had a p‐value of 0.06–1.00 on McNemar test, indicating no significant differences in the questionnaire responses between the two time points. However, over half of the participants responded “Don't know” to the question about self‐awareness of the disease. Interestingly, a study in Hong Kong 21 also found a noticeably higher percentage of “Don't know” responses to the same question. This may be partly owing to cultural differences. Even though the question seemed basic, it required an understanding of the concept of “gum disease” or “periodontal disease” to be able to identify themselves as having the disease. 40 This was also reflected in a study in Spain 41 that recruited participants who had their first visit to a dental hospital and some from the general population and found a high percentage of false positive cases (60.8%) on this question.
Routine dental visits correlated with better periodontal health. 42 However, our participants mostly visited the dentist less than once per year and tended to seek treatment only when they experienced symptoms. This was consistent with the ninth NOHS 4 finding that only approximately 30% of Thai individuals seek dental treatment annually. The unnoticeable early stage of periodontitis may prevent patients from seeking treatment. Additionally, a recent study demonstrated that the sensitivity of questions may depend on a patient's history of access to dental health care. 43 A population that lacks routine dental visits could directly affect the performance of questions about previous dental history, especially question 5. Accordingly, this may explain why question 5 was excluded from our final reduced model, despite being included in the original NHANES model. 8 Likewise, another study in Japan, 20 which included workers who had frequent dental checkups, found that questions 1 and 5 performed better and were included in their final model.
In this study, we tested the predictivity of three classifications: moderate/severe periodontitis (CDC/AAP), severe periodontitis (CDC/AAP), and stage III/IV periodontitis (EFP/AAP). In the univariate analysis, question 4 had the best predictive value among the eight questions. This question performed well in predicting severe periodontitis and was included in other regression models. 16 , 20 , 41 , 44 This agrees with a previous meta‐analysis that found that the question about tooth mobility had the highest validity in predicting severe periodontitis. 45
As noticeable symptoms of periodontitis, such as loose teeth, are expected in later stages, questions regarding signs and symptoms may be more suitable predictors than questions regarding self‐awareness of the disease. Nonetheless, increasing understanding and self‐awareness encourages individuals to seek treatment promptly. An Austrian study suggested that adding periodontal disease screening to a national survey helped raise awareness nationwide among the population, medical and dental personnel, and policymakers. 46
Demographic and signs and symptom‐related variables─age, education level, PI, spacing, pain, and dental visit frequency─showed good performance in predicting all case definitions tested.
In multivariable model analysis, questions valid for predicting “moderate/severe periodontitis” and “severe periodontitis” (CDC/AAP) were questions 1, 4, and 8. For predicting “stages III and IV periodontitis” (EFP/AAP), the only valid question was question 4. Interestingly, the only valid question for predicting all case definitions was the question indicating the symptoms of the disease, whereas questions related to treatment or information from the dentist were less predictable. Compared with previous studies, questions on dental flossing and mouth rinse performed diversely, likely owing to heterogeneity in population characteristics and behaviors.
AUCs of Model 1 comprising only the CDC/AAP self‐reported questionnaire, were above 0.69 (0.69–0.74), which is a satisfactory predictive ability. When additional questions regarding demographic data and periodontal risk factors were included (Model 2), the models performed better, with higher AUCs (0.86–0.88). All reduced models (Model 5) had useful levels of predictive ability (AUCs > 0.82, 0.82–0.86). 47 These results are consistent with prior studies showing better predictability when combined with other risk‐related factors; 8 , 21 a single measure is insufficient to predict the disease. A study using NHANES 2009–2010 data also found that a model that combined sociodemographic variables and CDC/AAP self‐reported questionnaire showed the best performance. 8
A Brazilian study (n = 585) in a population with a high prevalence of severe periodontitis (using EFP/AAP and CDC/AAP case definitions) also supports the NHANES 2009–2010 findings. 16 The final reduced model included four questions from the CDC/AAP self‐reported questionnaire: self‐perception of gum disease, teeth/gum health, loose teeth, and tooth loss history (Q1, Q2, Q4, Q5), as well as age, education level, number of teeth lost, and smoking status. Interestingly, this study found a higher prevalence of smoking (14.7%). In contrast, participants with DM were small. Therefore, patients with DM were excluded from the final model.
A study in Hong Kong with 68.6% periodontitis prevalence involving 7.8% current smokers and 4.9% DM also reported improved performance when demographic and lifestyle factors were included in the model. 21 The model predicting stage III/IV periodontitis indicated excellent accuracy (AUC = 0.953) and can be used as a feasible tool for detecting periodontitis. Factors contributing to this model's predictivity were age and smoking. Another study conducted on 949 Japanese individuals reported a periodontitis prevalence of 42.9% (6.2% severe periodontitis), with a higher percentage of current smokers (13.9%) and those with DM (6.8%). 20 Interestingly, smoking and DM were not included in the final model for predicting severe periodontitis. Variables included in the final model were age, sex, and overweight. However, smoking status was included in the final models for predicting moderate/severe periodontitis and total periodontitis, whereas DM was included only in the model predicting moderate/severe periodontitis. The level of cigarette consumption and the odds of having periodontitis revealed a dose‐dependent relationship. 48 Since smoking data collected in the above studies were not analyzed by actual consumption, they might not reflect the risk of the disease accurately.
To predict severe periodontitis, Model 5 yielded an AUC of 0.82, which was comparable with other studies. The original models from the NHANES study had an AUC of 0.83 when tested in an American population, 8 0.82 in a Dutch population (Dutch‐translated version), 18 and 0.87 in a Japanese population (Japanese‐translated version). 20
Our study has several strengths. First, to evaluate the validity of the self‐reported measures, the sample size was estimated based on the prevalence of severe periodontitis in a previous study. 29 Using the proportional stratified sampling method, we enrolled participants representing diverse age groups. Second, periodontal status and diagnosis were based on a full‐mouth examination performed by trained periodontists, which is considered the gold standard. 8 With partial‐mouth protocols, the prevalence could be underestimated and considered to have a lower level of validity for surveillance and research. 49 , 50 Third, diagnostic accuracy was tested against two case definitions. The CDC/AAP definition was constructed for epidemiological studies or surveillance surveys, whereas the new definition (EFP/AAP 2018) may be easier for practitioners to adapt and use.
However, our study has certain limitations. Since participant recruitment was based on age, only a small sample of patients had DM (5.2%) or were current smokers (5.6%), which are known periodontal risk factors. Owing to our recruitment from selected subdistrict health‐promoting hospitals in Chiang Mai, other demographic variables that could contribute to the disease, such as occupation and education level, may not have been equally distributed.
5. CONCLUSIONS
Our results indicated that the translated Thai version of the CDC/AAP self‐reported questionnaire, together with the risk‐related questionnaire, could predict severe periodontal disease in the Thai population with acceptable reliability.
5.1. Clinical relevance
Beyond research purposes and surveillance studies, with further validation, self‐reported questionnaires could be used in clinical settings to predict and screen for periodontal disease. Furthermore, if combined with a scoring system, the questionnaire results would be easier to interpret. This would allow not only dental personnel but also medical personnel or patients to use the tool for earlier disease identification.
AUTHOR CONTRIBUTIONS
All authors agree with the content of the manuscript. Chutinun Chaiwut contributed to the conception and design; the acquisition, analyses, and interpretation of data; drafting the manuscript and revising critically for important intellectual content and for final approval of the version to be published. Chidchanok Ruengorn contributed to the conception and design; the analyses and interpretation of data; revising critically for important intellectual content and for final approval of the version to be published. Panwadee Bandhaya contributed to the conception and design; supported study management and coordination; the analyses and interpretation of data; revising critically for important intellectual content and for final approval of the version to be published.
CONFLICT OF INTEREST STATEMENT
The authors declare no conflicts of interest.
Supporting information
Supporting Information
Supporting Information
ACKNOWLEDGMENTS
This study was supported by the Research grant for postgraduate students from the Royal College of Dental Surgeons of Thailand and the Faculty of Dentistry, Chiang Mai University. The authors wish to thank the staff of the Oral Diagnostic Clinic, Faculty of Dentistry, Chiang Mai University and Chiang Mai Provincial Public Health Office, together with Subdistrict Health Promotion Hospital at Ban Pa Khoi Nuea, Ban Tha Luk and Ban Chet Yot for their assistance in the preparation and data collecting process of this study. Additionally, the authors are grateful to Dr. Chanyanuch Wechwithayakhlung and Dr. Sasinant Kanchana‐at, post‐graduate students of Periodontology Residency Training Program, Faculty of Dentistry, Chiang Mai University for data gathering assistance.
Chaiwut C, Ruengorn C, Bandhaya P. Validity of a self‐reported questionnaire for periodontal status in a Thai population. J Periodontol. 2025;96:1413–1431. 10.1002/JPER.24-0707
Footnotes
Hu‐Friedy, Chicago, IL, USA.
Stata Corporation LP, College Station, TX, USA.
1USD = 34.259THB (July 31, 2023).
DATA AVAILABILITY STATEMENT
The data that support the findings of this study are available from the corresponding author upon reasonable request.
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Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Supplementary Materials
Supporting Information
Supporting Information
Data Availability Statement
The data that support the findings of this study are available from the corresponding author upon reasonable request.