Table 3: Effect of interaction of tooth surface and cariogenic bacteria on the changes of ICDAS score (Model 2 and 3).

S. mutans LB
Coefficient
(95% CI)
P-value Coefficient
(95% CI)
P-value
Mandibular Maxilla
Intercept 0.013 (0.005 - 0.021) 0.002 0.054 (0.044 - 0.065) <0.001
Mandibular S. mutans - Reference LB - Reference
S. mutans + 0.095 (0.079 - 0.112) <0.001 LB + 0.081 (0.060 - 0.101) <0.001
Maxilla S. mutans - 0.022 (0.006 - 0.038) 0.006 LB - 0.015 (-0.001 - 0.031) 0.071
S. mutans + 0.122 (0.103 - 0.141) <0.001 LB + 0.120 (0.093 - 0.147) <0.001
Tooth Type
Intercept 0.027 (0.014 - 0.039) <0.001 0.043 (0.034 - 0.053) <0.001
Anterior S. mutans - Reference LB - Reference
S. mutans + 0.055 (0.038-0.073) <0.001 0.060 (0.042 - 0.077) <0.001
Premolar S. mutans - -0.011 (-0.028 - 0.007) 0.237 LB - -0.004 (-0.019 - 0.012) 0.645
S. mutans + 0.061 (0.038 - 0.083) <0.001 LB + 0.091 (0.059 - 0.124) <0.001
Molar S. mutans - -0.002 (-0.020 - 0.017) 0.876 LB - 0.069 (0.047 - 0.091) <0.001
S. mutans + 0.194 (0.162 - 0.225) <0.001 LB + 0.216 (0.177 - 0.255) <0.001
Tooth Surface
Intercept <0.001 (-0.001 - 0.002) 0.767 0.019 (0.010 - 0.028) <0.001
Lingual S. mutans - Reference LB - Reference
S. mutans + 0.054 (0.039 - 0.069) <0.001 LB + 0.056 (0.033 - 0.078) <0.001
Buccal S. mutans - 0.060 (0.035 - 0.085) <0.001 LB - 0.071 (0.050 - 0.092) <0.001
S. mutans + 0.204 (0.175 - 0.233) <0.001 LB + 0.271 (0.225 - 0.317) <0.001
Approximal S. mutans - 0.005 (0.000 - 0.010) 0.069 LB - <0.001 (-0.011 - 0.011) 0.950
S. mutans + 0.050 (0.040 - 0.060) <0.001 LB + 0.048 (0.030 - 0.066) <0.001
Occlusal S. mutans - 0.054 (0.020 - 0.088) 0.002 LB - 0.222 (0.176 - 0.269) <0.001
S. mutans + 0.418 (0.358 - 0.478) <0.001 LB + 0.460 (0.373 - 0.548) <0.001

Models were specified in S1 File. When S. mutans or LB was positive in stimulated saliva, maxillary tooth was at risk when mandibular tooth set as a reference, molar tooth was at risk when anterior tooth set as a reference, and occlusal surfaces were at risk when lingual surfaces set as reference.
The coefficient of maxillary tooth, molar tooth and occlusal surface was higher than other classifications in both S. mutans and LD. The effects of both S. mutans and LB on the ICDAS score of these tooth properties were stronger than other classifications. S. mutans and LB also significantly affected the ICDAS score of all other classifications.