Karina Cogo

Use of Phytotherapy in Dentistry

Over the past decade, interest in drugs derived from medicinal plants has markedly increased. This study was aimed at a literature review focusing on studies investigating herbal drugs and other natural products, as well as their therapeutic application, side effects and possible drug interactions. Few studies were found to support their rational use in dentistry. Since there is an increasing use of phytotherapeutic agents in dentistry, further studies are needed to evaluate their safety and effectiveness for clinical use. Copyright

Liposome-encapsulated ropivacaine for topical anesthesia of human oral mucosa.

BACKGROUND:The elimination of pain caused by needle insertion for local anesthesia would be a significant advance in dentistry. METHODS:In this blinded cross-over study we evaluated the efficacy of liposome-encapsulated ropivacaine for topical anesthesia. Thirty healthy volunteers received 60 mg topical anesthetics: Liposome-encapsulated 1% ropivacaine, 1% plain ropivacaine, 2.5% lidocaine and 2.5% prilocaine mixture (EMLA), and 20% benzocaine gel, in the buccal fold of the upper-right canine for 2 min in different sessions. After insertion of 30-G needles, pain was rated on a visual analog scale (VAS). A pinprick test was used to measure the duration of topical anesthesia. The pulpar response was assessed by an electric pulp tester. RESULTS:VAS median and interquartile range (in cm) were 0.8 (0.4–1.5), 1.6 (0.8–2.6), 1.1 (0.3–2.7), 2.2 (0.9–2.9) for liposome-encapsulated ropivacaine, ropivacaine, EMLA, and benzocaine groups, respectively. The liposome-encapsulated ropivacaine group showed lower VAS mean values when compared with the benzocaine group (P = 0.0205). The median values and interquartile range for the duration of soft tissue anesthesia were 11 (7–14), 6.5 (4–11), 14 (11–16), and 7 (6–9) min for liposome-encapsulated ropivacaine, ropivacaine, EMLA, and benzocaine groups, respectively. EMLA and liposome-encapsulated ropivacaine were just as efficient for reducing pain, and showed longer soft tissue anesthesia when compared to the other local anesthetics (P = 0.0001). CONCLUSION:Liposomal-encapsulated 1% ropivacaine gel was equivalent to EMLA® for reducing pain during needle insertion and for the duration of soft tissue anesthesia. None of the topical anesthetics was effective for inducing pulpal anesthesia.

The effects of nicotine and cotinine on Porphyromonas gingivalis colonisation of epithelial cells.

Smoking is a risk factor for development of periodontitis. Porphyromonas gingivalis is an important colonizer of the subgingival crevice and is a major pathogenic agent in the initiation and progression of severe forms of periodontal disease. However, the effect of major cigarettes derivatives on P. gingivalis is poorly understood. The purpose of this study was to determine the influence of nicotine and cotinine on bacterial colonisation to epithelial cells. KB cells monolayers and P. gingivalis ATCC 33277 were exposed to 0.1, 10 and 100 microg/mL of nicotine and cotinine concentrations. The epithelial cells were incubated for 24 h while P. gingivalis was exposed to these substances until reach early logarithmic phase. After the incubation period, P. gingivalis ability to colonize KB cells was assayed. The number of cell-associated/invasive bacteria was assessed by counting the colony-forming units. 100 microg/mL cotinine significantly increased P. gingivalis association and invasion of epithelial cells, when the bacteria was exposed to this substance (p<0.05; ANOVA-Tukey test). No other condition or drug altered the bacteria colonisation ability (p>0.05). These data indicated that cotinine may interfere with P. gingivalis ability to associate and invade the epithelial cells. Further studies are needed to investigate whether oral cells might be more susceptible to be colonized by P. gingivalis in smokers.

Validation of the anti-bacteremic efficacy of an essential oil rinse in a Brazilian population: a cross-over study.

This cross-over study was conducted to assess the germ-killing efficacy of an essential oil mouthrinse (EOM) by determining the blood levels of microorganisms associated with induced bacteremia and investigating the prevalence of this event in Brazilians with mild-to-moderate gingivitis. Thirty four (31.19%) subjects positive for bacteremia induced by chewing a ration of apple were enrolled out of 109 screened subjects (50 males and 59 females). A difference of at least 10 colony forming units between the pre- and post-insult blood samples was defined as a positive result. For the following two weeks patients underwent a toothbrush plus fluoride dentifrice normalization period, and were then scheduled for the Phase I protocol as follows. At baseline I, subjects were instructed to chew a new apple ration, had new blood samples taken before and after this oral stimulus, and were randomly assigned to an experimental essential oil (n = 17) or placebo (P) mouthrinse (n = 17) treatment for 2 weeks. These procedures were repeated at the end of Phase I and then followed by a two-week wash-out period (tooth brushing with fluoride dentifrice). Bacteremia was again induced at baseline and at the end of Phase II, when subjects were crossed-over to the other EOM or placebo groups. Bacterial count differences between baseline and 2-week post-treatment (EOM versus P) in the blood samples collected were assessed by analysis of covariance. Mean aerobic counts decreased by 45.8%, whereas mean anaerobic counts decreased by 63.3% after EOM treatment. After the P treatment, aerobic bacteria increased by 28.4% and anaerobic bacteria decreased by 18.5%. This study validated this novel methodology and showed that the germ-killing action of EOM significantly reduced bacteremia.

Concentrations of metronidazole in human plasma and saliva after tablet or gel administration

The aim of this study was to determine the pharmacokinetic profile of metronidazole (Mtz) tablet and to compare Mtz gel and tablet concentrations in both blood plasma and saliva.

Psychological stress has no association with salivary levels of β-defensin 2 and β-defensin 3

BACKGROUND Recent studies suggest that stress can predispose an individual to the development of periodontal disease, but the exact biological mechanism is unknown. Considering that psychological stress can down-regulate the production of β-defensins (antimicrobial peptides produced in the oral cavity), the aim of the present study was to evaluate the association between stress and salivary levels of β-defensin 2 (HBD-2) and β-defensin 3 (HBD-3). METHODS For this purpose, seventy five volunteers, classified as periodontally healthy, were submitted to a psychological evaluation using a validated questionnaire (Questionnaire of Lipp-ISS). Following analysis of the questionnaires, the subjects were divided in two groups (Group A: Absence of stress and Group B: Presence of stress). Unstimulated saliva samples were collected and the concentration of total protein was determined using the BCA method, and the concentrations of HBD-2 and HBD-3 were determined by ELISA. RESULTS The levels of total protein did not show a statistically significant difference between the groups. Analyses of HBD-2 and HBD-3 concentrations indicate that the stress condition was not associated with the levels of either peptide in saliva (P=0.3664 for HBD-2 and P=0.3608 for HBD-3). CONCLUSION In periodontally healthy subjects, HBD-2 and HBD-3 levels are not influenced by stress.

Effect of articaine on mental nerve anterior portion: Histological analysis in rats

OBJECTIVES The aim of this study was to evaluate the possible toxic effects of articaine and lidocaine on mental nerve, due to the increasing number of paresthesia cases after nerve blocks. MATERIALS AND METHODS The drugs were injected in the anterior portion of mental nerve of 24 rats, divided into three groups: G1--4% articaine with 1:100,000 epinephrine; G2--2% lidocaine with 1:100,000 epinephrine and G3--plain 1:100,000 epinephrine solution. These solutions were injected in the right side of the rats mandible and the left side was used as control (0.9% saline solution). Previously to the injections, the animals were anesthetized with thiopental and, 24 h after the injections, their jaws were removed and submitted to routine histological techniques. A histopathological analysis was performed by optical microscopy. RESULTS An inflammatory infiltration was found around mental nerve, classified as intense for G3, moderate for G1 and light for both G2 and control groups. No injuries were found in nervous structure, despite the inflammatory reaction observed around it. CONCLUSION The results suggest that articaine is not toxic to the nervous structure and further studies are necessary to explain the possible relation between articaine injection and paresthesia.

Oral streptococci growth on aging and non-aging esthetic restorations after radiotherapy

The aim of this study was to examine Streptococcus mutans biofilm growth on both aged and non-aged restorative dental resins, which were submitted to therapeutic irradiation. Sixty-four disks of an esthetic restorative material (Filtek Supreme) were divided into 2 groups: aged group (AG) and a non-aged group (NAG). Each group was subdivided into 4 subgroups: non-irradiated and irradiated with 10Gy, 35Gy, and 70Gy. The biofilms were produced by Streptococcus mutans UA159 growing on both AG and NAG surfaces. The colony-forming units per mL (CFU/mL) were evaluated by the ANOVA and the Tukey LSD tests (α=0.05). AG presented smaller amounts of CFU/mL than the NAG before irradiation and after 10Gy of irradiation (p<0.05). AG irradiated with 35 and 70Gy showed increased amount of bacterial biofilm when compared to non-irradiated and 10Gy-irradiated disks (p<0.05). The exposure to ionizing radiation at therapeutic doses promoted changes in bacterial adherence of aged dental restorative material.

Bioequivalence study of two commercial amoxicillin suspension formulations in healthy human volunteers.

PURPOSE To compare the pharmacokinetic profiles and to evaluate the bioequivalence of two commercial amoxicillin suspension formulations (500 mg/5 mL AMOXIL®, reference formulation and AMOXI-PED®, test formulation) in healthy Brazilian volunteers. METHODS Under fasting condition, 25 volunteers (13 males and 12 females) were included in this randomized, open-label, two-period crossover (1-week washout interval) bioequivalence study. Blood samples were collected at pre-dose (0 hour) and 0.5, 1, 1.33, 1.66, 2, 2.5, 3, 4, 6, 8, and 12 hours after drug ingestion. Pharmacokinetic parameters (Cmax, tmax, t1/2, AUC0-tlast, and AUC0-∞) were calculated from plasma concentrations for both formulations in each subject. RESULTS Arithmetic mean values of the pharmacokinetic parameters were: Cmax = 12.004 (± 2.824) μg×mL-1; tmax = 1.118 (± 0.396) h; t1/2 = 1.226 (± 0.179) h; AUC0-tlast = 29.297 (± 6.007) μg×h×mL-1; and AUC0-∞ = 29.299 (± 6.007) μg×h×mL-1 for reference formulation and Cmax = 11.456 (± 2.825) μg×mL-1; tmax = 1.331 (± 0.509) h; t1/2 = 1.141 (± 0.133) h; AUC0-tlast = 28.672 (± 5.778) μg×h×mL-1; and AUC0-∞ = 28.693 (± 5.796) μg×h×mL-1 for test formulation. The confidence intervals (90% CI) for reference and test formulations were, respectively, 90.74 - 100.46% for Cmax and 93.62 - 103.61% for AUC0-t. CONCLUSION Based on the results, both formulations of amoxicillin evaluated in this study were considered bioequivalent according to FDA and ANVISA/Brazil criteria.

Avaliação da formação de biofilme de Streptococcus oralis em discos de titânio com micro e nanotopografia: estudo in vitro

Resumo O objetivo deste estudo foi comparar a formação inicial do biofilme em superfícies de titânio lisa comparando com superfícies com micro e nanotopografia. Discos de titânio foram produzidos e submetidos a variados métodos para a obtenção de superfícies: usinada, micro e nanotopografiae submetidos a formação de biofilme de Streptococcus oralis, um colonizador inicial do biofilme bucal. Todas as superfícies apresentaram resultados semelhantes em relação à adesão do biofilme bacteriano de S. oralis. Houve baixa produção de polissacarídeos de matriz extracelular em todos os grupos. As imagens do MEV mostraram uma adesão inicial de S. oralis, corroborando os resultados de quantificação bacteriana. O presente estudo demonstrou que as superfícies micro e nanotopografia não alteram a adesão da S. oralis em relação à superfície lisa nos discos de titânio.