The Effects Of Regular Preventive Scaling On The Clinical Indexes And Subgingival Plaque Microbes Of Fixed Orthodontic Patients

ObjectiveTo observe the decent periodontal scaling period for patients with fixed appliance, we detected the dynamic content changes of Porphyromonas gingivalis (P.gingivalis) and Fusobacterium nucleatum (F.nucleatuni) in subgingival plaque by the method of Real-time quantitative PCR, and we also observed changes of clinical periodontal clinical indexes before and during fixed orthodontic appliance therapy.Methods45 malocclusion patients were divided into three groups. Group A accepted periodontal scaling monthly and oral hygiene intrusion. Group B accepted periodontal scaling trimonthly and oral hygiene intrusion. Group C accepted periodontal scaling every six months and oral hygiene intrusion. The right maxillary first molar (16), the left maxillary central incisor (21),the left mandibular first premolar or the second premolar (34\35) and the right mandibular central incisor (41) were the observed teeth. The plaque index (PLI), gingival index (GI) and probing depth (PD)of the index teeth were examined, and subgingival plaque were collected in the Pre-treatment and treatment of 1.3,6.9 months. DNA was extracted from the subgingival plaque, and Real-time quantitative PCR were used to detect the contents of P.gingivalis and F.nucleatum.Results1.Periodontal indexes:Comparison among groups, at the 3rd and 6th months in treatment, the plaque index significantly increased in group B and C compared with the ones in group A; At the 6th month in treatment, gingival index and probing depth in group C were significantly higher than the ones in group A; At the 9th moths in treatment, the gingival index at group C was significantly higher than the one in group A. Comparison within groups.in group A, plaque index and gingival index at the 1st month were significantly higher than the ones at pretreatment; In group B. plaque index and gingival index at the 1st,6th,9th months in treatment significantly increased compared with ones at pretreatment. Plaque index in the 9th month was also significantly higher than the one at pretreatment. In group C. plaque index plus gingival index at the 3rd and 9th months in treatment were significantly higher than the ones at pretreatment. Plaque index, gingival index and probing depth at the 6th month were all significantly higher than the ones at pretreatment.2.Microbiological indexes:Comparison among groups, at the 6th months in treatment the percentage of P.gingivalis and F. nucleatum in group C were significantly higher than the ones in group A. At the 9th month in treatment the percentage of P.gingivalis significantly increased in group C compared with the one in group A. Comparison within groups, no significant difference was found in group A and B. In group C, at the 6th month in treatment, the contents of P.gingivalis and F. nucleatum were significantly higher than the pretreatment level.Conclusions1. Periodontal scaling trimonthly and oral hygiene instructions have control the gingivitis of patients with fixed appliance to some extent, which is more economical and convenient than scaling monthly. So we can do periodontal scaling trimonthly for orthodontic patients.2. Fixed appliance cause the percentage of Porphyromonas gingivalis and F. nucleatum significantly increasing, which indicate that there is a risk of periodontal tissue destruction.