Abstract: PURPOSE: Comparative analysis of MORSE, formic acid and Plank-Rychlo decalcification solution for the treatment of combined tooth-mandibular-periodontal tissues to explore their application value. METHODS: Specimens including normal teeth, jaws and periodontal tissues discarded from Department of Oral Pathology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine were collected and randomly divided into 3 groups to analyse the differences in decalcification time, staining effect and nucleic acid integrity of 3 different decalcification solutions. SPSS 23.0 software package was used for statistical analysis. RESULTS: The mean decalcification time was 4.5, 3.5 and 3.6 days in the MORSE, formic acid and Plank-Rychlo group, respectively. H-E staining scores were in descending order in the MORSE, formic acid and Plank-Rychlo group. Immunohistochemical staining showed that AE1/AE3, p63 and Ki67 scores in MORSE group were better than those in the formic acid group and the Plank-Rychlo group, and Vimentin staining indices showed no significant difference between the 3 groups. In the fluorescence in situ hybridisation results, normal fluorescence signals were detected in 15 cases in MORSE group, 1 case in formic acid group and 4 cases in Plank-Rychlo group. The mean DNA concentration was 1.987, 1.963 and 1.115 ng/μL in MORSE, formic acid and Plank-Rychlo group, respectively; and the mean RNA concentration was 13.03, 11.08 and 1.66 ng/μL, respectively. There was no significant difference in DNA concentration and RNA concentration between MORSE and formic acid group(P>0.05), and both DNA and RNA concentrations were higher in the 2 groups than those in Plank-Rychlo group(P<0.001). CONCLUSIONS: MORSE decalcification solution has comprehensive advantages in the treatment of combined tooth-mandibular-periodontal tissues and is of value in the clinical, teaching and research aspects of pathology.

Key words: Combined tooth-mandibular-periodontal tissues, Decalcifying solution, Staining effect, Nucleic acid integrity