Iontophoresis use for increasing drug penetration into root canals and dentinal tubules: A proof-of-concept study.

INTRODUCTION: The success of endodontic treatment depends on the significant disinfection of the root canal system, its irregularities, and dentinal tubules. However, achieving complete disinfection remains challenging, with frequent failures and occurrence of secondary infections. Here, we propose using iontophoresis to increase the penetration and distribution of disinfecting agents into root canals, using methylene blue for proof-of-concept. METHODS: The marker was applied in bovine root canals, and the radial distribution of the dye in the dentinal tubules was evaluated by optical microscopy. Iontophoresis was applied at 0.5 and 1.5 mA for 5 and 15 min. RESULTS: A significant statistical difference (p < 0.05) was observed in the marker penetration between passive and iontophoretic applications. Both current density and application time had an important effect on methylene blue distribution, with a greater efficacy delivery to the apical region achieved after 1.5 mA for 5 min or 0.5 mA for 15 min, showing longer application time can compensate for lower application current. CONCLUSION: Iontophoresis increases the penetration and distribution of methylene blue into bovine root canals and dentinal tubules, including its innermost portions. CLINICAL SIGNIFICANCE: Iontophoresis has shown to be a promising technique for root canal and dentinal tubule disinfection.

Novel technologies to improve the treatment of endodontic microbial infections: Inputs from a drug delivery perspective.

Endodontic microbial infections are still a challenge for an effective treatment for being biofilm-mediated and very refractory to conventional therapies. Biomechanical preparation and chemical irrigants cannot fully eradicate biofilms due to the anatomic structure of the root canal system. Instruments employed in biomechanical preparation and irrigants solution cannot reach the narrow and deepest portion of root canals, especially the apical thirds. In addition, aside from the dentin surface, biofilms can also infiltrate dentine tubules and periapical tissues, compromising treatment success. Therefore, different technologies have been investigated to achieve a more effective outcome in the control of endodontic infections. However, these technologies continue to face great difficulties in reaching the apical region and eradicating biofilms to avoid the recurrence of infection. Here, we present an overview of the fundamentals of endodontics infections and review technologies currently available for root canal treatment. We discuss them from a drug delivery perspective, highlighting each technology's strength to envision the best use of these technologies.

Phagocytic activity of monocytes and neutrophils in patients with periodontitis, whether or not associated to type 2 diabetes.

Phagocytic functions by neutrophils/ monocytes and biochemical parameters were assessed in peripheral blood of patients with periodontitis, whether or not associated to type 2 diabetes, or patients with type 2 diabetes, or systemically healthy people. Fifty-eight participants were divided into four groups: Control - systemically and periodontally healthy patients (C, n=16), Periodontitis (P, n=14), Type 2 Diabetes (DM, n=11) and Periodontitis associated with type 2 diabetes (DMP, n=17). Blood samples were used to analyze phagocytic activity and the production of superoxide anion using optical microscopy. Significantly lower phagocytic activity of neutrophils was observed in non-opsonized samples (p = 0.008, Kruskal- Wallis) of the periodontitis group and in opsonized samples (p = 0.029, Kruskal-Wallis) of the periodontitis associated with type 2 diabetes group when these groups were compared to the healthy individuals when a 20:1 yeast: phagocyte stimulus was used. Periodontitis patients, whether associated (p = 0.0007, sensitized; Kruskal-Wallis, 20:1) or not with diabetes (p = 0.018 and 0.0007, in the proportions 5:1 and 20:1 yeast: monocyte respectively in sensitized samples; Kruskal-Wallis) also showed lower phagocytic function of monocytes compared to the control group. There was no significant difference in the production of superoxide anion among the evaluated groups. Severe clinical attachment loss was associated with lower levels of HDL in periodontitis patients and a higher percentage of A1C in diabetes with periodontitis patients (p<0.05; Pearson and Spearman correlations, respectively). Patients with both associated diseases had higher levels of triglycerides and CRP (p<0.001, Kruskal-Wallis) compared to patients with diabetes only. The results of the present study suggest that periodontitis negatively interferes with the innate immune response and may represent a major risk of systemic complications such as cardiovascular disease in diabetic patients or even in healthy individuals.

As funções fagocíticas de neutrófilos/monócitos e parâmetros bioquímicos foram avaliados no sangue periférico de pacientes com periodontite com ou sem diabetes do tipo 2, ou em pacientes com diabetes tipo 2, ou em pessoas saudáveis sistemicamente. 58 participantes foram divididos em quatro grupos: Controle - pacientes sistemicamente e periodontalmente saudáveis (C, n = 16), Periodontite (P, n = 14), Diabetes Tipo 2 (DM, n = 11) e Periodontite associada a diabetes tipo 2 (DMP, n = 17). Amostras de sangue foram usadas para analisar a atividade fagocítica e a produção de ânion superóxido por microscopia óptica. Observou-se menor atividade fagocítica dos neutrófilos em amostras não opsonizadas (p = 0,008, Kruskal-Wallis) do grupo periodontite e em amostras opsonizadas (p = 0,029, Kruskal-Wallis) do grupo periodontite associada ao diabetes tipo 2 quando esses grupos foram comparados aos indivíduos saudáveis sob um estímulo de levedura:monócito de 20:1. Pacientes com periodontite associada (p = 0,0007, sensibilizados; Kruskal-Wallis, 20: 1) ou não com diabetes (p = 0,018 e 0,0007, nas proporções 5: 1 e 20: 1 de levedura: monócito, respectivamente, em amostras sensibilizadas; Kruskal- Wallis) também demonstraram menor função fagocítica dos monócitos em comparação com o grupo controle. Não houve diferença significativa na produção de ânion superóxido entre os grupos avaliados. A perda de inserção clínica grave foi associada a níveis mais baixos de HDL na periodontite e maior percentual de A1C nos pacientes com periodontite associada ao diabetes (p<0,05; correlações de Person e Spearman, respectivamente). Os pacientes com ambas as doenças associadas apresentaram níveis mais altos de triglicerídeos e PCR (p<0,001, Kruskal- Wallis) em comparação aos pacientes com somente diabetes. Os resultados do presente estudo sugerem que a periodontite interfere negativamente na resposta imune inata e pode representar um risco maior para complicações sistêmicas, como a doença cardiovascular, em pacientes com diabetes ou mesmo em indivíduos saudáveis.

Quantification of lipid bodies in monocytes from patients with periodontitis.

OBJECTIVES: For the first time in the history of periodontics, the production of lipid bodies by monocytes was assessed from blood of patients with periodontitis in comparison to systemically healthy individuals. The purpose of this study was to compare the lipid body frequency within monocytes between healthy patients and those with periodontal disease. MATERIALS AND METHODS: A total of 30 participants (11 males and 19 females), were divided between orally healthy control subjects (C, n = 16) and periodontitis subjects (P, n = 14), in a cross-sectional study. Both groups were systemically healthy. The following clinical periodontal parameters were assessed: probing depth, clinical attachment level, visible plaque index and gingival bleeding on probing index. Blood samples were collected to obtain monocytes containing lipid bodies, which were analyzed by light microscopy. RESULTS: The periodontitis group demonstrated a higher corpuscular index than the control group (nonopsonized p = .0296 or opsonized p = .0459; Mann-Whitney). The frequency of monocyte cells containing lipid bodies (basal p = .0147, opsonized p = .0084 or nonopsonized, p = .026; Mann-Whitney) was also higher compared to those observed in healthy individuals. CONCLUSIONS: The data suggest that periodontitis may contribute to a higher production of lipid bodies. It was also hypothesized that a major production of lipid bodies by monocytes in severe periodontitis, compared to orally healthy subjects, could interfere with the innate immune response or represents a higher reservoir of cholesterol esters within macrophages and a major risk to systemic implications, such as atherosclerosis.

Phagocytic activity of monocytes and neutrophils in patients with periodontitis, whether or not associated to type 2 diabetes / Atividade fagocítica de monócitos e neutrófilos em pacientes com periodontite, associada ou não ao diabetes tipo 2

ABSTRACT Phagocytic functions by neutrophils/ monocytes and biochemical parameters were assessed in peripheral blood of patients with periodontitis, whether or not associated to type 2 diabetes, or patients with type 2 diabetes, or systemically healthy people. Fifty-eight participants were divided into four groups: Control - systemically and periodontally healthy patients (C, n=16), Periodontitis (P, n=14), Type 2 Diabetes (DM, n=11) and Periodontitis associated with type 2 diabetes (DMP, n=17). Blood samples were used to analyze phagocytic activity and the production of superoxide anion using optical microscopy. Significantly lower phagocytic activity of neutrophils was observed in non-opsonized samples (p = 0.008, Kruskal- Wallis) of the periodontitis group and in opsonized samples (p = 0.029, Kruskal-Wallis) of the periodontitis associated with type 2 diabetes group when these groups were compared to the healthy individuals when a 20:1 yeast: phagocyte stimulus was used. Periodontitis patients, whether associated (p = 0.0007, sensitized; Kruskal-Wallis, 20:1) or not with diabetes (p = 0.018 and 0.0007, in the proportions 5:1 and 20:1 yeast: monocyte respectively in sensitized samples; Kruskal-Wallis) also showed lower phagocytic function of monocytes compared to the control group. There was no significant difference in the production of superoxide anion among the evaluated groups. Severe clinical attachment loss was associated with lower levels of HDL in periodontitis patients and a higher percentage of A1C in diabetes with periodontitis patients (p<0.05; Pearson and Spearman correlations, respectively). Patients with both associated diseases had higher levels of triglycerides and CRP (p<0.001, Kruskal-Wallis) compared to patients with diabetes only. The results of the present study suggest that periodontitis negatively interferes with the innate immune response and may represent a major risk of systemic complications such as cardiovascular disease in diabetic patients or even in healthy individuals.

RESUMO As funções fagocíticas de neutrófilos/monócitos e parâmetros bioquímicos foram avaliados no sangue periférico de pacientes com periodontite com ou sem diabetes do tipo 2, ou em pacientes com diabetes tipo 2, ou em pessoas saudáveis sistemicamente. 58 participantes foram divididos em quatro grupos: Controle - pacientes sistemicamente e periodontalmente saudáveis (C, n = 16), Periodontite (P, n = 14), Diabetes Tipo 2 (DM, n = 11) e Periodontite associada a diabetes tipo 2 (DMP, n = 17). Amostras de sangue foram usadas para analisar a atividade fagocítica e a produção de ânion superóxido por microscopia óptica. Observou-se menor atividade fagocítica dos neutrófilos em amostras não opsonizadas (p = 0,008, Kruskal-Wallis) do grupo periodontite e em amostras opsonizadas (p = 0,029, Kruskal-Wallis) do grupo periodontite associada ao diabetes tipo 2 quando esses grupos foram comparados aos indivíduos saudáveis sob um estímulo de levedura:monócito de 20:1. Pacientes com periodontite associada (p = 0,0007, sensibilizados; Kruskal-Wallis, 20: 1) ou não com diabetes (p = 0,018 e 0,0007, nas proporções 5: 1 e 20: 1 de levedura: monócito, respectivamente, em amostras sensibilizadas; Kruskal- Wallis) também demonstraram menor função fagocítica dos monócitos em comparação com o grupo controle. Não houve diferença significativa na produção de ânion superóxido entre os grupos avaliados. A perda de inserção clínica grave foi associada a níveis mais baixos de HDL na periodontite e maior percentual de A1C nos pacientes com periodontite associada ao diabetes (p<0,05; correlações de Person e Spearman, respectivamente). Os pacientes com ambas as doenças associadas apresentaram níveis mais altos de triglicerídeos e PCR (p<0,001, Kruskal- Wallis) em comparação aos pacientes com somente diabetes. Os resultados do presente estudo sugerem que a periodontite interfere negativamente na resposta imune inata e pode representar um risco maior para complicações sistêmicas, como a doença cardiovascular, em pacientes com diabetes ou mesmo em indivíduos saudáveis.