Comparison Of Effects Of Removable Partial Dentures With Lingual Plate Or Sublingual Bar On Periodontal Index And Subgingival Plaque For Residual Teeth

Objectives:This study aimed to compare the effect of removable partial dentures with lingual plate or sublingual bar on periodontal health through the change of periodontal index and subgingival plaque for residual teeth.Materials and Methods:16patients who wanted to accept RPDs restoration were chosen randomly.8were treated with lingual plates and8with sublingual bars.Comparisons were made about the two groups’ index change regarding PLI, GI, PD and TM. Detections of the amount of culturable bacteria and detected microbial proportion around abutment teeth were compared after the insertion of RPDs between groups.Results:1. At the end of1month and3months, the PLI and GI index of lingual plate patients was statistically significant (p<0.05), while the PLI and GI index of sublingual bar patients was not statistically significant (p>0.05). The comparison of the PLI and GI index at the end of1month and3months between lingual plate patients and sublingual bar patients was statistically significant (p<0.05). The PLI and GI index of lingual plate patients decreased at the end of6months and recorded little difference with sublingual bar patients, while the TM index of lingual plate patients improved significantly compared with sublingual patients. The PD index of the two groups was not significantly affected by the insertion of RPDs.2. The amount of subgingival culturable bacteria of both lingual plate patients and sublingual bar patients increased significantly (p<0.05) at the end of3months and6months. Gram negative bacilli proportion increased with the increase of RPDs insertion time. Compared with sublingual bar patients, the amount of subgingival culturable bacteria carried by lingual plate patients was statistically significant (p<0.05) at the end of6months, and Gram negative bacilli proportion presented statistical significance (p<0.05) over all periods.Conclusions:1. As to both lingual plate patients and sublingual bar patients, their amount of subgingival plaque and proportion of Gram negative bacilli increased at all periods after the insertion of RPDs.2. Compared with sublingual bar patients, subgingival plaque was more likely to accumulate in the oral environment of lingual plate patients but remained stable after6months. RPDs with lingual plate design decreased tooth mobility index.