Out of 255 participants a total of 252 students were analysed in the present study. 139 (55.2%) of participants were male and 113 (44.8%) were female. 133 (52.8%) of them aged 13–14 and 119 (47.2%) were 15–16 years old. The highest percentage for the distribution of severity of malocclusion was observed for grade 3 (25.8%). Which indicates moderate need for treatment. 23.4% had grade 4 malocclusion, 22.2% of participants had grade 2, 18.7% and 9.9% had grade 1 and 5 respectively. There was no statistically significant difference in malocclusion severity between male and female participants and age groups (
p > 0.05). Mean scores, standard deviation and observed range of the OHIP-14 and its seven domains are shown in Table
1. The mean score and standard deviation for OHIP-14 was 8.64 (7.32) for boys and 11.05 (9.41) for girls. There was statistically significant difference in mean score of OHIP-14 between male and female (
p = 0.023). The difference was not significant among age group (
p > 0.05) Table
2. In group comparison using One Way ANOVA followed by Bonferroni Pos Hoc test no statistically significant difference was observed in OHIP-14 score of students with different severity of malocclusion assessed by IOTN DHC (Table
3). While in group comparison of OHIP-14 domains psychological discomfort and psychological disability domains were the affected domains. In correlation analysis a weak positive relationship was observed between OHIP-14 and IOTN DHC (r = 0.186;
p < 0.01). To evaluate the factors that affect OHIP-14 score multiple linear regression analysis was performed as in Table
4. The effect of age was not significant on overall OHIP-14 score (B = − 2.069,
p > 0.05) (Table
5). OHIP-14 was significantly and positively associated with sex. Females had higher impact scores than males with B = 2.413 and
p < 0.05. This association becomes stronger in multivariate model (B = 2.673; 95% CI 0.639–4.707;
p < 0.05). It also explains about 2.1% variability among sex (r square = 0.021). There was a significant association between IOTN DHC and OHIP-14 (B = 1.235
p < 0.05) as well significant association was also obtained in multivariate analysis (B = 1.28; 95% CI 0.47–2.09;
p < 0.05). According to regression model a grade increase in the IOTN DHC, will cause 1.28-fold (B = 1.28; 95% CI 0.478–2.09;
p < 0.01) increase in overall OHIP-14 score, it also explains about 3.2% of variability (r = 0.032) among grades of IOTN DHC. In other words, the severity of malocclusion is associated with higher impact on OHRQoL.
Table 1
Mean, standard deviation and range observed in Oral Health Impact Profile-14 (OHIP-14)
Functional limitation | 0.7 ± 1.1 | 0–5 |
Physical pain | 1.5 ± 1.2 | 0–7 |
Psychological discomfort | 2.2 ± 1.7 | 0–8 |
Physical disability | 1.4 ± 1.6 | 0–8 |
Psychological disability | 1.6 ± 1.7 | 0–8 |
Social disability | 0.8 ± 1.3 | 0–6 |
Handicap | 1.1 ± 1.5 | 0–8 |
OHIP-total | 33.6 ± 3.4 | 0–45 |
Table 2
Comparison of OHIP-14 score between sexes and age groups
Sex | | | | |
Male | 8.64 (7.32) | − 2.41 (− 4.48, − 0.33) | − 2.28 (250) | 0.023* |
Female | 11.05 (3.39) | | | |
Age (year) | | | | |
13–14 | 10.69 (8.45) | 2.06 (− 0.05, 4.14) | 1.96 (250) | 0.051 |
15–16 | 8.63 (8.22) | | | |
Table 3
Mean score and SD of OHIP-14 domains according to severity of malocclusion
Grade 1 (no need for treatment) | 0.4 ± 0.8 | 1.2 ± 1.2 | 1.6 ± 1.4 | 0.9 ± 1.0 | 0.9 ± 1.0 | 0.7 ± 1.0 | 0.8 ± 1.1 | 6.8 ± 5.4 |
Grade 2 (mild treatment need) | 0.9 ± 1.2 | 1.5 ± 1.1 | 2.0 ± 1.5 | 1.5 ± 1.6 | 1.5 ± 1.5 | 0.8 ± 1.2 | 0.8 ± 1.1 | 9.3 ± 7.4 |
Grade 3 (moderate treatment need) | 0.8 ± 1.2 | 1.4 ± 1.4 | 2.2 ± 1.8 | 1.5 ± 1.7 | 1.8 ± 1.8 | 0.8 ± 1.5 | 1.1 ± 1.6 | 10.5 ± 10.3 |
Grade 4 (severe treatment need) | 0.5 ± 0.8 | 1.7 ± 1.2 | 2.6 ± 2.0* | 1.5 ± 1.6 | 2.0 ± 1.9* | 0.9 ± 1.3 | 1.4 ± 1.8 | 11.0 ± 8.5 |
Grade 5 (extreme treatment need) | 1.2 ± 1.4 | 1.5 ± 1.0 | 2.8 ± 1.5* | 2.0 ± 1.8 | 2.1 ± 1.7 | 0.9 ± 1.4 | 0.9 ± 1.4 | 12.2 ± 9.1 |
Table 4
Multivariate linear regression model showing association of sex and IOTN-DHC with OHIP-14
OHIP-14 | Sex (female) | 2.67 | 2.58 | 0.639–4.70 | 0.010 |
| IOTN-DHC | 1.28 | 3.13 | 0.47–2.09 | < 0.001 |
Table 5
Simple linear regression model showing association of age, sex and IOTN-DHC with OHIP-14 score
Age (15–16 years) | 0.015 | − 2.069 | − 1.965 | − 4.143 to 0.05 | 0.05 |
Sex (female) | 0.021 | 2.413 | 2.288 | 0.336–4.489 | 0.02 |
IOTN-DHC | 0.034 | 1.235 | 2.975 | 0.418–2.053 | 0.03 |