Effect Following Periodontal Treatment With Er:YAG Laser

Chronic periodontitis is a high incidence of chronic infectious diseases, which is one of the main causes of tooth loss. As plaque is the initiating factor of periodontal diseases, the primary role of the periodontal therapy is to remove and control the plaque effectively. Current conventional periodontal treatments mainly use ultrasonic and hand instrument to do scaling and root planing, which have been shown to achieve good clinical outcomes. However these treatments are time-consuming and may cause root hypersensitivity, the variation of root anatomy can affect the treatment effeciency.Er:YAG laser, a kind of solid pulse laser, can effectively remove the diseased periodontal tissue with little smear layer, and is reported to have a better effect of sterilization and bacteriostasis with little thermal damage at the sametime. Er:YAG laser is considered to be the most promising laser for periodontal treatment. In recent years, the effectiveness of Er:YAG laser has been proofed in the treatment of chronic periodontitis which includes removing periodontal pathogen, diseased cementum and controlling periodontal inflammation. However, different results are reported on the comparsion of Er:YAG laser and traditional periodontal treatment methods.So it still needs further research on the efficacy of Er:YAG laser in the treatment of chronic periodontitis.Periodontal pathogens can be detected in gingival crevicular fluid frequently and it is related to clinical indices. Sampling from gingival crevicular fluid is simple and noninvasive and easily repeated. Periodontal pathogens in gingival sulcus fluid can reflect the efficacy of periodontal therapy by Er:YAG laser.The study aims to compare clinical indices of chronic periodontitis before and after treatment by Er:YAG laser alone or the traditional methods(ultrasonic scaling + manual root planing). And then using technique of PCR to test the changes of periodontal pathogens. The study may provides evidence-based and theoretical basis for laser treatment of periodontitis and provides practical experience for the further promotion of the laser in the treatment of periodontitis, meanwhile provides the basis for periodontal treatment effect.Experiment 1: Comparison Clinical Index of the Chronic Periodontitis before and after Treatment by Er: YAG Laser and Conventional TherapyObjectiveTo compare the clinical effects following periodontal treatment with Er:YAG laser or with traditional therapy for patients with chronic periodontitis.MethodsIn present study, 27 patients with chronic periodontitis were randomly treated in a split-mouth design with Er:YAG laser(160m J/pulse, 10HZ)(test group) or a traditional therapy(SRP)(control group).The following clinical parameters were recorded before treatment(baseline) and after treatment at 6 weeks, 3 months, 6 months postoperatively, including probing depth(PD), bleeding index(BI), attachment loss( AL). The changes inter-group and intra-group are analyzed.ResultsPD, BI and AL values were reduced significantly at 6weeks, 3 months and 6 months after treatment in both groups. And no significant difference was found from 6 weeks to 6 months postoperatively. The sites with6mm≥PD≥4mmat baseline treated with Er:YAG laser demonstrated PD decrease to(3.79±0.57)mm and(3.60±0.56)mm at 6 weeks and 3months postoperatively; the sites with 6mm≥PD≥4mm treated with SRP demonstrated PD decrease to(3.54±0.48) mm and to( 3.39±0.50) mm at the corresponding time point. The result demonstrates advantage of SRP with P=0.036 and P=0.039 respectively. The effect of SRP is significantly better when BI was compared inter-group at 6 weeks and 6months postoperatively( P=0.007, P=0.015, P=0.000). The effect of SRP is better in changing AL at 3months and 6months postoperatively(P<0.05).No difference for all clinical parameters except BI were found at sites with PD≥7mm at 6weeks, 3months and 6months postoperatively.ConclusionEr: YAG laser can improve clinical index of periodontitis effectively. Its effect is similar to SRP at sites with PD≥7mm. But the effect of SRP is better at sites with 6mm≥PD≥4mm. Er:YAG laser could be an effective way for the treatment of severe periodontitis.Experiment 2:Periodontopathogen levels following the use of an Er:YAG laser in the treatment of chronic periodontitisObjectiveTo detect the prevalence of 6 kinds of periodontal pathogens in gingival crevicular fluids from patiences with chronic periodontitis before and after treatment, and to evaluate the s terilization and antimicrobial effect of Er:YAG laser.MethodsIn present study 22 patients with chronic periodontitis were randomly treated in a split-mouth design with Er:YAG laser(160m J/pulse,10HZ)(test group) or traditional therapy(SRP)(control group). PCR based on 16 Sr RNA was used to detect Pg, Tf, Td, Pi, Fn, Pn before treatment(baseline) and after treatment at 6 weeks, 3 months, 6 months.ResultsIn the Er:YAG laser group, the prevalent rates of Pg(71.87%), Tf(40.63%)reduced at 3 months and 6 months postoperatively Pg(31.25%,43.75%),Tf(9.38%,12.5%). Td(68.75%) reduced to 50%, 50%, 40.63% at 6 weeks, 3 mont hs and 6 months postoperatively. Pi(31.25%)reduced to 6.25%,12.5% at 6 weeks and 3 months postoperatively, but it increased to 18.75% at 6 months. In the SRP group, the prevalent rates of Pg(29.03%,19.35%,19.35%), Tf(9.68%,6.45%, 16.13%), Td(41.94%, 41.94%, 22.58%) 6weeks, 3 months and 6 mont hs postoperatively were significantly lower than those at baseline Pg(64.51%),Tf(51.61%), Td(80.65%). Pi(38.71%)reduced to 6.45%, 12.90% at the end of 3 months and 6 months postoperatively.Pn, Fn showed no significant difference inter-group and intra-group.ConclusionEr:YAG laser can improve clinical index of periodontitis effectively. Its effect is similar to SRP at the sites with PD≥7mm. Er:YAG laser could be an effective way for the treatment of severe periodontitis.Both of the two therapies can reduce Pg, Tf, Td, Pi in gingival crevicular fluids. However the effect of SRP is earlier than Er:YAG laser and can sustain to 6 months after treatment.