Effect of amorphous calcium phosphate nanoparticles and polypeptides on microleakage at the edge of Class Ⅴ cavity backfill

ZHOU Ru-li; GUO Hong-tao; ZHU Wan-chun; BAO Shu-yin

doi:10.19538/j.kq.2025.02.007

Abstract：Objective To study the effect of amorphous calcium phosphate nanoparticles(NACP)and synthetic polypep-tides(NH2-CQDSETRTFYDSHAKRHHGYKRKFHEKHHSHRGY-COOH,CYP)on microleakage at the edge of Class Ⅴ cavity backfill in isolated teeth.Methods A total of 80 impacted molars extracted from patients treated in the Stoma-tology Department of the Affiliated Hospital of North Sichuan Medical College from April to June 2024 were collected,and Class Ⅴ cavities were prepared in the neck of the cheek and tongue side of the isolated teeth.All the isolated teeth were divided into total acid etching group and self-etching group with 40 teeth in each group(80 Class Ⅴ cavities)by random number table method.Then,according to the bonding and filling treatment method,they were divided into control subgroup(coated with general adhesive only),NACP subgroup(with mixed coating of general adhesive and 30％NACP by mass fraction),CYP subgroup(coated with general ad-hesive after 1％CYP treated cavity by mass fraction),and NACP+CYP subgroup(with mixed coating of general ad-hesive and 30％NACP by mass fraction after 1％CYP treated cavity by mass fraction).There were 10 isolated teeth in each subgroup(20 Class Ⅴ cavities).The isolated teeth were immersed in 2％methylene blue solution for 24 h after cyclic aging treatment,and the microleakage degree of occlu-sal wall and gingival wall of each group was observed and evaluated.Results The microleakage scores of internal gingi-val wall in all subgroups were higher than those of occlusal wall,and the differences were statistically significant(all P＜0.05).There were statistically significant differences in microleakage scores of occlusal wall and gingival wall between to-tal acid etching group and self-etching group(all P＜0.05).The microleakage scores of the occlusal wall and gingival wall of the NACP+CYP subgroups in the total and self-etching groups were lower than those in the control subgroup.The occlusal wall microleakage scores of NACP subgroup and CYP subgroup in total acid etching group were lower than those of control subgroup,and the gingival wall microleakage scores of NACP+CYP subgroup were lower than those of NACP subgroup,with statistical difference(all P＜0.05).There were no significant differences in wall or gingival microleakage scores between each pair of groups with the same name between total and self-etching groups(P＞0.05).Conclusion Both NACP and CYP can reduce the degree of microleakage at the edge of Class Ⅴ cavity backfill to a certain extent,and the effect of combined application of both is better.