Learn About Panda Teeth

The pandas teeth are arranged in two rows, upper and lower dental arches, and are categorized into incisors, canines, premolars, and molars based on their morphology and function. Incisors are not well-developed, canines are short and conical, and there is no gap between canines and premolars. The molars of giant pandas lack the sharp features typical of carnivorous animals. The fourth premolar and molars have enlarged crowns and broad chewing surfaces. The nodules on the panda tooth surface are sharp, with short crowns and complex structures, representing an adaptation to the physiological function of cutting and crushing bamboo, their main diet.

The growth and development of panda teeth are related to the level of nutrition in captivity, with individual variations in growth speed and sequence.

(1) Development of Panda Deciduous Teeth:
1. Initially, at 75-90 days old, the first panda tooth to emerge is usually the lower canine, with a few cases of the lower premolar emerging first.
2. Around 84 days old, the lower incisors start growing, with most growing by around 100 days. Between 75-90 days, 2-10 panda teeth may emerge, with considerable variation in dental patterns.
3. At 90-100 days old, 5-14 panda teeth may emerge, with significant variations in dental patterns.
4. Between 100-120 days old, 8-22 panda teeth may emerge, mostly ranging from 13 to 16 panda teeth; dental patterns still exhibit significant variations.
5. From 120-130 days old, 15-24 panda teeth may emerge, with most having a dental pattern of 2130/1130 or 1130/1130.
6. Between 130-140 days old, 20-24 panda teeth may emerge, with a dental pattern mostly being 2130/2130 or 2130/1130.
7. By 150 days old, they usually have all 24 teeth, with a dental pattern of 2130/2130. The dental pattern of deciduous teeth remains unchanged.

(2) Development of panda Permanent Teeth:
1. Generally, at 7 months old, pandas start shedding deciduous teeth, with the first pair of upper premolars emerging, occasionally also the lower incisors.
2. At 8-9 months old, the first pair of upper and lower molars emerges, with a dental pattern of 1010/1010 or 1010/1000.
3. At 10 months old, the second pair of upper and lower molars emerges, with a dental pattern of 2010/2010 or 2010/2000.
4. Between 11-13 months old, the third pair of upper and lower molars emerges. At 12-13 months old, the first permanent molars start growing, with a dental pattern of 3041/3031 or 3041/3041.
5. At 14 months old, all molars have grown, and some pandas begin growing canines, reaching a total of 36-38 teeth. The dental pattern is generally 3042/3033 or 3042/3043.
6. Between 14-15 months old, canines start growing, and by 18 months old, they are mostly complete. Some pandas have delayed canine growth, resulting in a total of 40-42 teeth. The dental pattern is generally 3142/3133 or 3142/3143.

In the field of scientific research:

In February 2019, a research team from the Materials Fatigue and Fracture Laboratory at the Institute of Metal Research, Chinese Academy of Sciences, made the groundbreaking discovery that panda teeth have the ability to self-repair. According to Dr. Liu Zengqian from the laboratory, the minerals in panda teeth are arranged vertically and closely, forming a "strong forest" of enamel, similar to the structure of trees. Organic matter fills the tiny gaps between these "mineral trees." The deformation and damage to enamel, as well as its automatic recovery at the microscopic level, are achieved through these small gaps. The natural organic matter undergoes swelling under hydrated conditions, leading to phenomena such as increased flexibility of polymer chains and a lowered glass transition temperature, enabling the self-repair of enamel. The moisture in panda saliva significantly enhances this self-repair effect. This study not only provides evidence for the early adaptation capabilities of giant pandas but also offers new insights for the development of innovative biomimetic materials. It has also contributed to advancements in research on biomimetic composite denture materials for human teeth matching and high-strength, high-conductivity contact materials.