Clinical study of the microbial profile, LPS and LTA in teeth with pulp vitality associated with periodontal disease

Author(s)

Lidiane Mendes Louzada

• Document type: Master's Dissertation
• Press: Piracicaba, SP.
• Institution: Universidade Estadual de Campinas (UNICAMP). Faculdade de Odontologia de Piracicaba
• Defense date: 2019-02-21

Examining board members

Brenda Paula Figueiredo de Almeida Gomes; Luciano Tavares Angelo Cintra; Caio Cezar Randi Ferraz

• Advisor: Brenda Paula Figueiredo de Almeida Gomes

Abstract

Long-term periodontal disease can cause pulpal changes. The aim of this clinical study is to investigate the microbiota and to quantify the levels of endotoxins (LPS) and lipoteichoic acid (LTA) in root canals (RC) and periodontal pockets (PP) of teeth submitted to endodontic therapy with chronic periodontal disease with secondary endodontic involvement that did not respond to the periodontal therapy, before and after the chemo-mechanical preparation (CMP) and after the use of an intracanal medication (ICM) for 30 days. Ten teeth with periodontal disease and positive response to the pulp sensitivity test that were under periodontal treatment for at least 6 months were selected. Samples from PP and RC were collected by using sterile/apirogenic paper points. The microbiota of PP and RC was characterized using molecular methods ¿ Nested PCR and Checkerboard DNA-DNA hybridization. Quantification of LPS and LTA in both sites were performed using LAL Pyrogent 500 and ELISA, respectively. Bacterial DNA was detected in all PP and RC samples (10/10). By Nested PCR, of the 17 bacteria investigated, all were present in the PP and 11 in the RC. A high prevalence of E. faecalis and F. nucleatum was observed in PP and RC at all stages of endodontic treatment. By CB, 39 species were detected at some time of the endodontic treatment in the PP and 25 species in the RC. In PP, 12 bacteria had a load between 105 and 106 cells and F. nucleatum had a load of approximately 106 cells. In the RC, only 2 species showed microbial load between 105 and 106. Of the 14 bacteria common to both microbial identification methods. Nested PCR presented higher sensitivity than CB (p <0.05). Levels of LPS were detected in PP and RC. After CMP, there was a reduction of 31.59% in LPS levels in PP (p <0.05) and after ICM in 73.38% (p <0.05). In the RC, after CMP, a bacterial reduction of 80% (p <0.05) and after ICM of 90% was observed (p <0.05). LTA was detected in PP and RC. After CMP, there was a reduction of 34.49% (p <0.05) and after ICM of 28.45% ICM (p> 0.05) in PP. In RC, after CMP, there was a reduction of 11.55% (p <0.05) and after MIC of 47.93% (p <0.05). It was concluded that the microbiota of PP and RC of teeth with vital pulp associated with periodontal disease is polymicrobial, with presence of Gram-negatives, Gram-positives, facultative and strict anaerobic bacteria. CMP and ICM promoted reduction of the infectious content of PP and RC. The methods used were effective for characterizing the microbiota of PP and RC. CMP and ICM were effective in reducing LPS levels in PP and RC. ICM was effective in significantly reducing LTA levels in PP and RC (AU)

• FAPESP's process: 17/18838-1 - Characterization of the microbiological and endotoxic profile of patients with chronic periodontitis and secondary endodontic involvement submitted to the endodontic therapy
• Grantee: Lidiane Mendes Louzada
• Support Opportunities: Scholarships in Brazil - Master