A total of 1,205 12-year-old students participated in this study, with a survey response rate of 88.5%. The reliability of oral health status assessments, as measured by kappa statistics, ranged from 0.84 to 0.93. The overall prevalence of dental caries was 44%, and the mean DMFT score was 1.14. The prevalence of oral diseases and dental caries scores were evaluated in different groups divided by whether PFS had been performed (Table 1).
Table 1
The relationship between PFS and tooth condition.
| PFS | Non-PFS | P |
N (%) | 252 (20.9%) | 953 (79.1%) | |
DMFT > 0 | 110 (43.7%) | 433 (45.4%) | 0.613 |
DMFT (‾x ± SD) | 1.004 ± 1.479 | 1.289 ± 2.053 | 0.013 |
DMFT > 0 (First permanent molar) | 95 (37.7%) | 366 (38.4%) | 0.837 |
DMFT (First permanent molar (‾x ± SD) | 0.623 ± 0.934 | 0.787 ± 1.185 | 0.020 |
Gum bleeding (%) | 135 (53.6%) | 405 (42.5%) | 0.002 |
Calculus (%) | 88 (34.9%) | 269 (28.2%) | 0.038 |
DMFT: decayed, missing, and filled teeth; PFS: pit and fissure sealing |
Table 1 shows that the overall caries (DMFT) rate of 12-year-old children with and without PFS was similar (P = 0.613). Moreover, the caries rate (DMFT) in the first permanent molars also did not differ significantly between the two groups (P = 0.837). Thus, PFS did not prevent the occurrence of caries per se. However, PFS effectively reduced the overall number of caries (P = 0.013) and number of caries of the first permanent molar (P = 0.020). Furthermore, the gingival bleeding rate (P < 0.002) and dental calculus presence rate (P = 0.038) were higher in the PFS group than in the Non-PFS group.
Table 2 shows the relationship between the PFS rate, oral health behavior, and sociodemographic characteristics. PFS was statistically significantly associated with 12-year-old children's residential areas, parents' education level, brushing frequency, use of dental floss, and oral examinations at a medical institution (all P < 0.01). Students from cities, with fathers and with mothers with higher education, who brushed their teeth twice or more times per day, who used dental floss (30.0%), and who visited medical institutions for oral examinations had higher rates of pit and fissure closures. PFS had no significant association with sex, being an only child, having parents who worked in other places, the brushing methods used, use of fluoride toothpaste, the frequency of eating sweets, dental pain, dental trauma, or having participated in oral health care courses (all P > 0.05).
Table 2
The relationships of pit and fissure sealing rate with oral health behavior and sociodemographic characteristics.
Variable | Total N (%) | Pit and fissure sealing N (%) | Chi-square value | P-value |
Sex | | | | |
Male | 608 (50.5%) | 126 (20.7%) | 0.027 | 0.871 |
Female | 597 (49.5%) | 126 (21.2%) | | |
Single-child family | | | | |
Yes | 389 (32.3%) | 87 (22.4%) | 0.697 | 0.404 |
No | 814 (67.7%) | 165 (20.3%) | | |
Residential area | | | | |
Urban | 555 (46.1%) | 138 (24.9%) | 9.716 | 0.002 |
Rural | 650 (53.9%) | 114 (17.5%) | | |
Paternal educational level Junior college degree or below | 896 (87.4%) | 170 (19.0%) | 26.190 | < 0.001 |
Bachelor degree or above | 129 (12.6%) | 50 (38.8%) | | |
Maternal education level Junior college degree or below | 889 (88.1%) | 167 (18.8%) | 35.106 | < 0.001 |
Bachelor degree or above | 120 (11.9%) | 51 (42.5%) | | |
Parents work in other places At least one parent works in another places | 339 (28.1%) | 69 (20.4%) | 0.089 | 0.765 |
Neither parent works in other places | 866 (71.9%) | 183 (21.2%) | | |
Tooth-brushing duration | | | | |
Brushing for 3 minutes or more Brushing for less than 3 minutes | 314 (26.1%) 891 (73.9%) | 57 (18.2%) 195 (21.9%) | 1.956 | 0.162 |
Tooth-brushing method | | | | |
Correct brushing methods: Circle method, Modified bass brushing technique Incorrect brushing: horizontal brushing | 321 (26.6%) 884 (73.4%) | 61 (19.0%) 191 (21.6%) | 0.965 | 0.326 |
Tooth-brushing frequency ≥ Twice per day | 642 (53.3%) | 154 (22.9%) | 7.854 | 0.005 |
≤ Once per day | 563 (46.7%) | 91 (18.2%) | | |
Use dental floss | | | | |
Yes | 353 (29.3%) | 106 (30.0%) | 24.878 | < 0.001 |
No | 850 (70.7%) | 146 (17.2%) | | |
Use fluoride toothpaste Yes | 223 (18.5%) | 57 (25.6%) | 3.518 | 0.061 |
No | 980 (81.5%) | 195 (19.9%) | | |
Frequency of eating desserts and candies | | | | |
At least once a day Less than once a day | 286 (23.8%) 918 (76.2%) | 61 (21.3%) 191 (20.8%) | 0.036 | 0.850 |
Frequency of consuming sweetened drinks | | | | |
At least once a day | 118 (9.8%) | 27 (22.9%) | 0.301 | 0.583 |
Less than once a day | 1086 (90.2%) | 225 (20.7%) | | |
Frequency of consuming sweetened milk and yogurt At least once a day | 224 (18.6%) | 51 (22.8%) | 0.562 | 0.454 |
Less than once a day | 980 (81.4%) | 201 (20.5%) | | |
Toothache experience Yes | 598 (49.7%) | 121 (20.2%) | 0.348 | 0.555 |
No | 606 (50.3%) | 131 (21.6%) | | |
Tooth injury | | | | |
Yes | 196 (16.3%) | 37 (18.9%) | 0.636 | 0.425 |
No | 1004 (83.7%) | 214 (21.4%) | | |
Oral examination in a medical institution Yes | 809 (67.4%) | 199 (24.6%) | 20.515 | < 0.001 |
Never | 392 (32.6%) | 52 (13.3%) | | |
Had taken courses on oral health care in the past year Yes No | 281 (59.7%) 190 (40.3%) | 77 (27.4%) 53 (27.9%) | 0.014 | 0.907 |
Table 3 shows the relationship between the PFS rate and oral health knowledge, attitude, and self-assessment of oral condition through a questionnaire survey. Correct answers to questions on the effectivity of brushing in preventing gingival inflammation (P = 0.014), whether PFS can protect teeth (P < 0.001), and whether oral disease may affect general health (P < 0.001) were associated with a higher rate of PFS.
Table 3
Relationship between pit and fissure sealing rate and oral health knowledge, attitude, and self-assessment of oral condition.
Variables | Total N (%) | Pit and fissure sealing N (%) | Chi-square Value | P-value |
Oral health knowledge | | | | |
1. Gum bleeding is normal when brushing teeth | | | | |
Correct answer | 733 (60.9%) | 161 (22.0%) | 1.211 | 0.271 |
Wrong answer | 471 (39.1%) | 91 (19.3%) | | |
2. Bacteria can cause gingivitis | | | | |
Correct answer | 998 (82.9%) | 219 (21.9%) | 3.621 | 0.057 |
Wrong answer | 206 (17.1%) | 33 (16.0%) | | |
3. Tooth brushing is not effective in preventing gingival inflammation | | | | |
Correct answer | 1020 (84.7%) | 226 (22.2%) | 6.068 | 0.014* |
Wrong answer | 184 (15.3%) | 26 (14.1%) | | |
4. Bacteria can cause dental caries | | | | |
Correct answer | 804 (66.8%) | 180 (22.4%) | 3.108 | 0.078 |
Wrong answer | 400 (33.2%) | 72 (18.0%) | | |
5. Eating sugar can cause dental caries | | | | |
Correct answer | 918 (76.2%) | 192 (20.9%) | 0.001 | 0.981 |
Wrong answer | 286 (23.8%) | 60 (21.0%) | | |
6. Fluoride does not protect teeth | | | | |
Correct answer | 694 (57.6%) | 157(22.6%) | 2.835 | 0.092 |
Wrong answer | 510 (42.4%) | 95(18.6%) | | |
7. Pit and fissure sealing can protect teeth | | | | |
Correct answer | 514 (42.7%) | 144 (28.0%) | 27.207 | < 0.001 |
Wrong answer | 690 (57.3%) | 108 (15.7%) | | |
8.Oral disease may affect general health | | | | |
Correct answer | 876 (72.8%) | 206 (23.5%) | 12.991 | < 0.001 |
Wrong answer | 328(27.2%) | 46(14%) | | |
Oral health attitudes | | | | |
1. Oral health is important to your life | | | | |
Correct answer | 1184 (98.4%) | 249 (21.0%) | 0.310 | 0.578 |
Wrong answer | 19 (1.6%) | 3 (15.8%) | | |
2. Regular oral examination is very important | | | | |
Correct answer | 1091 (90.7%) | 233 (21.4%) | 1.183 | 0.277 |
Wrong answer | 112 (9.3%) | 19 (17.0%) | | |
3. Tooth quality is innate and has nothing to do with taking measures to prevent caries | | | | |
Correct answer | 1123 (93.3%) | 237 (21.1%) | 0.250 | 0.617 |
Wrong answer | 80 (6.7%) | 15 (18.8%) | | |
4. Prevention of dental disease depends on oneself first Correct answer | 1155 (96.1%) | 242 (21.0%) | 0.003 | 0.957 |
Wrong answer | 47 (3.9%) | 10 (21.3%) | | |
Self-oral evaluation | | | | |
Very good/Good | 378 (31.4%) | 88 (23.3%) | 0.563 | 0.453 |
Average | 635 (52.7%) | 135 (21.3%) | 5.021 | 0.025 |
Poor/Very poor | 191 (15.9%) | 29 (15.2%) | | |
Table 4 shows the results of the logistic regression analysis regarding factors influencing PFS. We identified six factors with an OR > 1 (factors promoting PFS): residence in urban areas, use of dental floss, understanding that PFS can protect teeth, and oral examination at medical institutions. Factors with OR < 1 (factors related to lack of PFS) were not understanding that gingival bleeding when brushing teeth is not normal, and a lower maternal educational level (junior college degree or below).
Table 4
Logistic regression analysis of the risk factors related to pit and fissure sealing.
| B | SE | Wald statistic | P | OR | 95% CI |
Lower | Upper |
Urban vs Rural (Urban) | 0.332 | 0.162 | 4.202 | 0.040 | 1.394 | 1.015 | 1.916 |
Is gingival bleeding normal? (No) | -0453 | 0.162 | 7.866 | 0.005 | 0.636 | 0.463 | 0.872 |
Educational level of mother (Junior college degree or below) | -0.899 | 0.214 | 17.653 | < 0.001 | 0.407 | 0.268 | 0.619 |
Is floss used? (Yes) | 0.551 | 0.168 | 10.716 | 0.001 | 1.735 | 1.248 | 2.414 |
Does pit and fissure sealing protect teeth? (Yes) | 0452 | 0.163 | 7.694 | 0.006 | 1.572 | 1.142 | 2.164 |
Oral examination in a medical institution? (Yes) | 0.410 | 0.194 | 4.464 | 0.035 | 1.507 | 1.030 | 2.204 |
Nagelkerke R2 = 0.110; -2 Log-likelihood = 974.226 |
B, regression coefficient; P, significance level; OR, odds ratio; CI, confidence interval.