动物造模,药效评价,猪牙髓炎模型 z-bio 2024-07-08 403

　　1. Experimental method: Five Chinese experimental miniature pigs weighing 14-26kg were used, with three males and two females. Select the first permanent molars of the upper and lower jaw, and create a pulpitis model with bilateral mandibular lateral incisors. Small pigs were anesthetized by intramuscular injection of compound thiamethoxazole at a rate of 0.1 ml/kg, and the oral area and mouth were thoroughly cleaned. Disinfect experimental teeth and periodontal tissue with 2% iodine tincture, use a high-speed turbine drill with a complete cooling device to prepare holes on the surface of the experimental molars, and prepare V-type holes for the mandibular incisors. Carefully puncture the pulp, with a diameter of 2-3mm, and rinse repeatedly with physiological saline to fully stop bleeding. The control group was covered with calcium hydroxide paste, with zinc oxide clove oil paste as the base, and filled with zinc phosphate cement. The experimental group was directly covered with zinc oxide clove oil paste and filled with zinc phosphate cement. Strict aseptic operation during surgery. Animals were euthanized at 2 weeks, 4 weeks, and 3 months postoperatively, and experimental and control teeth, numbered, and fixed with 10% formalin, were quickly removed. Observation of histopathology: Microwave decalcification of a mixture of hydrochloric acid, formic acid, and sodium chloride, gradient alcohol dehydration, conventional paraffin embedding for continuous sectioning, with a thickness of 5 μ m. HE staining and observation under a light microscope.

　　2. Experimental results: After 2 weeks of calcium hydroxide pulp capping surgery in the control group, a thin layer of pulp necrosis was observed below the pulp perforation, with proliferation of fibroblasts and occasional formation of calcified masses. Square shaped odontogenic cells were found around the pulp, and inflammatory cells infiltrated significantly. There was also a small amount of vascular proliferation and congestion in the tissue. After one month of pulp capping surgery, restorative dentin clusters can be seen forming in the teeth, with a dense structure and tubular dentin. There are columnar odontogenic cells around them, but no complete dentin bridge formation. The pulp below the restorative dentin is congested with a small amount of inflammatory cells. After 3 months of pulp capping surgery, a complete reparative dentin bridge can be seen, with irregular shape and tubular dentin, tightly combined with the primary dentin, and normal pulp.

　　Two weeks after the pulp capping surgery with zinc oxide clove oil paste in the experimental group, there was significant infiltration of inflammatory cells below the perforation, vascular dilation, partial pulp necrosis, and no reparative dentin formation. One month after surgery, a small amount of irregular calcified masses can be seen in the pulp cavity, surrounded by odontogenic cells, and no complete dentin bridge formation. Three months after surgery, reparative dentin formed with irregular morphology and surrounded by odontogenic cells, but the perforations were not completely closed.