Tianjin University research team develops new technology for efficient teeth whitening and sterilization

Medical Network, August 13 News reporter learned from Tianjin University on the 12th that the team of Professor Zhang Lei of the School of Chemical Engineering of the school and the team of Professor Zhang Xu of Tianjin Medical University Stomatological Hospital have recently proposed a new type of photodynamic dental treatment strategy
.
This research was supported by the National Natural Science Foundation of China, and the results have been published in the international authoritative journal "Advanced Functional Materials"
.

 

Tooth discoloration and the diseases it causes are the most common dental health problems
.
Ingestion of cigarettes, colored foods and beverages can cause tooth contamination and discoloration
.
Contaminated teeth provide nutrition for the growth of bacteria.
A large number of bacteria accumulate and proliferate on the teeth to form a biofilm, which in turn leads to dental plaque, enamel demineralization, dental caries and periodontitis
.
Once this kind of biofilm is formed, it is very difficult to remove, and it is difficult for the body's immune cells and foreign antibiotics to break through it to kill internal bacteria
.

 

At present, the main methods of tooth whitening are physical whitening, such as polishing and patching
.
However, physical therapy requires professional dentists to operate and can cause irreversible mechanical damage to tooth enamel
.
Compared with physical whitening, "chemical bleaching" based on the production of active oxygen is a whitening method that is less harmful to teeth
.
Photodynamic therapy is a new type of chemical bleaching technology with high precision.
Its principle is: the photosensitizer is excited by light in the presence of molecular oxygen to produce active oxygen
.
During the treatment process, the position and time of the light source, photosensitizer can be precisely adjusted to achieve "on-demand production" of active oxygen to avoid damage to normal tissues
.

 

Protoporphyrin is the most common photosensitizer in photodynamic therapy, but protoporphyrin is hardly soluble in water, which severely limits its ability to generate active oxygen and hinders its practical application in the body
.
The team of Professor Zhang Lei of Tianjin University designed a zwitterion -modified hydrophilic porphyrin
.
Due to the high hydrophilicity of the zwitterionic group, the water solubility of the modified protoporphyrin is significantly enhanced
.
Experimental results show that due to its reasonable electron donor and acceptor structure and avoiding molecular aggregation, the use of this hydrophilic photosensitizer for photodynamic therapy can increase the active oxygen yield by 8 times
.
The teeth stained by coffee, tea, grape juice, and blueberry juice have achieved non-destructive whitening, and 95% of the biofilm of Streptococcus mutans on the crown of the tooth has been effectively removed
.

 

　　According to Professor Zhang Lei, "This new photodynamic dental treatment strategy has the dual effects of non-destructive tooth whitening and eradicating biofilm
.
We hope to whiten teeth and prevent and treat biofilm-induced plaque, enamel demineralization, Tooth decay, periodontitis and other diseases provide more convenient, safe and effective methods
.
" (End)

　　Medical Network, August 13 News reporter learned from Tianjin University on the 12th that the team of Professor Zhang Lei of the School of Chemical Engineering of the school and the team of Professor Zhang Xu of Tianjin Medical University Stomatological Hospital have recently proposed a new type of photodynamic dental treatment strategy
.
This research was supported by the National Natural Science Foundation of China, and the results have been published in the international authoritative journal "Advanced Functional Materials"
.

 

　　Tooth discoloration and the diseases it causes are the most common dental health problems
.
Ingestion of cigarettes, colored foods and beverages can cause tooth contamination and discoloration
.
Contaminated teeth provide nutrition for the growth of bacteria.
A large number of bacteria accumulate and proliferate on the teeth to form a biofilm, which in turn leads to dental plaque, enamel demineralization, dental caries and periodontitis
.
Once this kind of biofilm is formed, it is very difficult to remove, and it is difficult for the body's immune cells and foreign antibiotics to break through it to kill internal bacteria
.

 

　　At present, the main methods of tooth whitening are physical whitening, such as polishing and patching
.
However, physical therapy requires professional dentists to operate and can cause irreversible mechanical damage to tooth enamel
.
Compared with physical whitening, "chemical bleaching" based on the production of active oxygen is a whitening method that is less harmful to teeth
.
Photodynamic therapy is a new type of chemical bleaching technology with high precision.
Its principle is: the photosensitizer is excited by light in the presence of molecular oxygen to produce active oxygen
.
During the treatment process, the position and time of the light source, photosensitizer can be precisely adjusted to achieve "on-demand production" of active oxygen to avoid damage to normal tissues
.

 

　　Protoporphyrin is the most common photosensitizer in photodynamic therapy, but protoporphyrin is hardly soluble in water, which severely limits its ability to generate active oxygen and hinders its practical application in the body
.
The team of Professor Zhang Lei of Tianjin University designed a zwitterion -modified hydrophilic porphyrin
.
Due to the high hydrophilicity of the zwitterionic group, the water solubility of the modified protoporphyrin is significantly enhanced
.
Experimental results show that due to its reasonable electron donor and acceptor structure and avoiding molecular aggregation, the use of this hydrophilic photosensitizer for photodynamic therapy can increase the active oxygen yield by 8 times
.
The teeth stained by coffee, tea, grape juice, and blueberry juice have achieved non-destructive whitening, and 95% of the biofilm of Streptococcus mutans on the crown of the tooth has been effectively removed
.

 

　　According to Professor Zhang Lei, "This new photodynamic dental treatment strategy has the dual effects of non-destructive tooth whitening and eradicating biofilm
.
We hope to whiten teeth and prevent and treat biofilm-induced plaque, enamel demineralization, Tooth decay, periodontitis and other diseases provide more convenient, safe and effective methods
.
" (End)