1 month old - 1 year old
2 months old - 3 years old
3 months old - 5 years old
6 months old - 9 years old
9 months old - 13 years old
1 year old —— 17 years old
1 and a half years old - 20 years old
2 years old - 24 years old (the mind has become stable at this time)
3 years old —— 28 years old
4 years old —— 32 years old
5 years old —— 36 years old
6 years old - 40 years old (beginning to enter middle age, body functions begin to degrade, making it unsuitable for reproduction)
7 years old —— 44 years old
8 years old - 48 years old
9 years old - 52 years old
10 years old - 56 years old
11 years old - 60 years old
12 years old - 64 years old
13 years old - 68 years old
14 years old - 72 years old
15 years old - 76 years old
16 years old - 80 years old
17 years old - 84 years old
18 years old - 88 years old
19 years old - 94 years old
20 years old - 96 years old
Age and dental condition
19-28 days milk incisors grow in
21-28 days 3rd milk premolar erupts
21-35 days, primary canine teeth grow in
Day 21-42: The 4th primary premolars erupt
28-42 days 2nd milk premolar erupts
2 months old, all deciduous teeth are in full length
3-4 months old: Replace the 1st and 2nd incisors and the permanent incisors grow in
4-5 months old: Replace the 1st deciduous premolar, and the permanent premolar will grow in
4-6 months old: canine teeth are replaced and permanent teeth grow out
4-7 months old: Replace the 2nd rear molar and grow permanent teeth
5-6 months old: Replace the 3rd incisor and grow permanent teeth
5-7 months old: 2nd, 3rd, and 4th permanent premolars grow in line
6-9 months old, the 3rd mandibular permanent rear molars are in full length
9-10 months old, all replacements complete
1 year old, permanent teeth are long, white and bright, with pointed incisors
1 and a half years old, the tip of the first mandibular incisor is worn
2 and a half years old, the tip of the second mandibular incisor is worn
3 and a half years old, the tip of the first maxillary incisor is worn
4 and a half years old, the tip of the 2nd maxillary incisor is worn
5 years old, the tip of the 3rd mandibular incisor begins to wear, and the 1st and 2nd incisors wear in a rectangular shape
6 years old, the tip of the third mandibular incisor begins to wear, the canine teeth are blunt, and the mandibular incisors are worn
8 years old, the first mandibular incisor begins to wear, and the grinding surface tilts forward
10 years old, the grinding surfaces of the 2nd mandibular and 1st maxillary incisors are oval
11-15 years old, incisors are lost and the teeth are incomplete
16-20 years old, canine tooth loss
