No.	Abbr.	Description of Abbreviation
1	KN	anterior nasal spike
2	BZ	lower mandibular margin (a point in the projection of a line parallel to the X axis passing through the anterior nasal spike)
3	S11	incisal margin of tooth 11
4	S21	incisal margin of tooth 21
5	S12	incisal margin of tooth 22
6	S22	incisal margin of tooth 22
7	S31	incisal margin of tooth 31
8	S41	incisal margin of tooth 41
9	S32	incisal margin of tooth 32
10	S42	incisal margin of tooth 42
11	C13	top of cusp of canine 13
12	C23	top of cusp of canine 23
13	C33	top of cusp of canine 33
14	C43	top of cusp of canine 43
15	C14	top of buccal cusp of tooth 14
16	C15	top of buccal cusp of tooth 15
17	C24	top of buccal cusp of tooth 24
18	C25	top of buccal cusp of tooth 25
19	C34	top of buccal cusp of tooth 34
20	C35	top of buccal cusp of tooth 35
21	C44	top of buccal cusp of tooth 44
22	C45	top of buccal cusp of tooth 45
23	AV	the ratio between the distance |KN-BZ| and U (the width of the interdental handle-mouth of the X-ray camera)
24	CQ	the ratio between S11-W11 and AV distance
25	CS	the ratio between S12-W12 and AV distance
26	CU	the ratio between S21-W21 and AV distance
27	CW	the ratio between S22-W22 and AV distance
28	CY	the ratio between S31-W31 and AV distance
29	DA	the ratio between S41-W41 and AV distance
30	DC	the ratio between S32-W32 and AV distance
31	DE	the ratio between S42-W42 and AV distance
32	DG	the ratio between S14-W14 and AV distance
33	DK	the ratio between S24-W24 and AV distance
34	DS	the ratio between S34-W34 and AV distance
35	DO	the ratio between S44-W44 and AV distance
36	DW	the ratio between S13-W13 and AV distance
37	DY	the ratio between S23-W23 and AV distance
38	EC	the ratio between S33-W33 and AV distance
39	EA	the ratio between S43-W43 and AV distance
40	DI	the ratio between S15-W15 and AV distance
41	DM	the ratio between S25-W25 and AV distance
42	DU	the ratio between S35-W35 and AV distance
43	DQ	the ratio between S45-W45 and AV distance
44	MLP	multilayer perceptron
45	RBF	radial basis function
46	RMSE	root mean square error