Inflammatory and degenerative effects of induced osteoarthritis/rheumatoid arthritis models on temporomandibular joint of rats.

OBJECTIVE: The present study compared three models of induction of osteoarthritis (OA) and rheumatoid arthritis (RA) in the temporomandibular joint (TMJ) of rats. DESIGN: The induction method was by injection of complete Freund's adjuvant (CFA) + type II bovine collagen (CII). Twenty-four adult male rats were divided into four groups (n = 6): G1: Sham, 50 µL of 0.9% sodium chloride at the base of the tail and in each TMJ; G2: OA, 50 µL CFA+CII in each TMJ; G3: RA+OA, 100 µL of CFA+CII at the base of the tail and 50 µL CFA+CII in each TMJ; G4: RA, 100 µL of CFA+CII at the base of the tail. All injections were repeated 5 days later. Twenty-three days after the first injection, the animals were sacrificed and the TMJs were submitted to histomorphometric analysis and measurement of cytokines. The Kruskal-Wallis and Dunn tests were used (alpha=0.05). RESULTS: The total thickness of the condylar cartilage increased in G2 in relation to the other groups, G3 and G4 reduced in relation to G1; and G2 and G4 reduced in relation to G2 and G3. The levels of IL-1ß, IL-6 and TNF-α increased in the three induction models compared to G1. The level of IL-10 increased in G2 compared to the other groups and reduced in G3 and G4 compared to G1. CONCLUSION: CFA+CII induced inflammation and degeneration compatible with RA (advanced chronic stage) when injected in the tail, and compatible with OA (acute stage or early disease) when injected only in the TMJ.

The effect of association of aspirin and omega 3 in rat temporomandibular joint with induced arthritis.

This study aimed to evaluate the effects of omega-3 (ω3) polyunsaturated fatty acids, in association with aspirin (AA), on the morphology of cytokine release in the temporomandibular joint (TMJ) of rats induced with rheumatoid arthritis (IR) by injecting 100 µL of complete Freund's adjuvant with bovine type II collagen at the tail base. Thirty-two adult male rats were divided into treatment groups: Sham, treated with 0.9% sodium chloride (NaCl) p.o.; IR-control, treated with 0.9% NaCl p.o.; IR-ω3 treated with ω3 PUFAS (85 mg/kg/day p.o.); and IR-ω3 + AA treated with ω3 (85 mg/kg/day p.o.) + AA (20 mg/kg/day i.p.). After maintained treatment for seven days, the animals were euthanized. Bilateral TMJs from each rat were removed and one was subjected to histological immunoassays and enzyme-linked immunosorbent assays to assess interleukin (IL)-1ß, tumor necrosis factor-α, and IL-10 levels. Data analysis was performed using the Kruskal-Wallis and Dunn tests. In the IR-ω3 and IR-ω3 + AA groups, the TMJ was greater than in the IR-control group (P < 0.0001). The addition of AA did not improve the effects of ω3 (P = 0.0698). Similarly, the addition of AA conferred no additional effects on the cytokine levels (P > 0.05); however, it increased the proteoglycan density, compared with ω3 alone. We found that ω3 exhibited anti-inflammatory activity in arthritic rats, and the addition of AA increased proteoglycan density, but did not affect cytokine expression.

Omega 3 polyunsaturated fatty acids: Potential anti-inflammatory effect in a model of ovariectomy and temporomandibular joint arthritis induction in rats.

OBJECTIVE: To evaluate the effect of polyunsaturated fatty acid-type omega 3 (ω3) on the temporomandibular joint (TMJ) of ovariectomized rats (OVX) with rheumatoid arthritis (RA). DESIGN: Rheumatoid arthritis was induced using complete Freund's adjuvant and type II bovine collagen injected at the base of the tail. Twenty-four adult female rats were treated by gavage and divided into four groups: G1: Sham, treated with 0.9% NaCl; G2: OVX, treated with 0.9% NaCl; G3: OVX+RA treated with 0.9% NaCl; G4: OVX+RA+ω3 treated with omega 3 (300 mg/kg/day). The induction of rheumatoid arthritis in groups G3 and G4 was performed 21 days after OVX, treatments were started 15 days after the induction of rheumatoid arthritis, maintained for 7 days, and killed. Bilateral TMJs were removed and assigned to morphometric analysis by micro-computed tomography and immunoassay to assess levels of cytokines IL-1ß, IL-6, TNF-α, and IL-10. RESULTS: Higher levels of inflammatory cytokines were found in the G2 and G3 (P < 0.05) and anti-inflammatory cytokines in the G1 and G4. TMJ analysis by micro-computed tomography showed a higher percentage of bone volume (median - interquartile deviation) in G1 (96.2-1.1) than in the G2 (91.5-2.0, P = 0.0374) and G3 (85.1-5.2, P = 0.0001) but showed no statistically significant differences with the G4 (93.1-1.7, P = 0.79). CONCLUSIONS: Omega 3 successfully reduced TMJ damage in rats caused by ovariectomy and induced rheumatoid arthritis, and is a promising alternative for bone repair and attenuation of inflammatory processes.

Effectiveness of Acupuncture in Dental Surgery: A Randomized, Crossover, Controlled Trial.

OBJECTIVES: The objective of this crossover clinical study was to evaluate the effectiveness of Energy Regulation with Acupuncture in clinical occurrences in impacted lower third molar surgeries. METHODS: The sample consisted of 22 patients with two impacted third molars, in symmetrical position; divided into two groups: Test Group (TG) with Real Energy Regulation Group and Sham Group (SG) with Acupuncture without Energy Regulation function. The extraction was performed 30 days apart. Energy flow (Ryodoraku Method) and energy regulation performed before extraction were measured. Heart Rate (HR) and Blood Pressure (BP) were evaluated before and after energy regulation and after surgery, residual edema was measured by facial measurements (angle of the mandible to tragus (A-T); angle of the mandible to labial commissure (A-LC); angle of the mandible to the wing of the nose (A-WN); angle of the mandible to the corner of the eye (A-CE); angle of the mandible to the chin (A-C); and mouth opening by the interincisal distance, before and after seven days of surgery. To quantify intraoperative bleeding (ml), blood was aspirated along with the saline solution using a portable vacuum pump adaptor. The amount of saline solution used was subtracted from the final amount of aspirated fluid. RESULTS: Mean of bleeding was lower in TG (p = 0.0392). There were significant differences between groups in facial distances: A-LC (p = 0.010), A-WN (p = 0.030) and A-C (p = 0.008). CONCLUSION: Energy regulation with real acupuncture was effective in reducing postoperative residual edema and intraoperative bleeding.

Age and sex estimation based on pulp cavity volume using cone beam computed tomography: development and validation of formulas in a Brazilian sample.

OBJECTIVES: To develop and validate formulas for age and sex estimation based on the pulp cavity volume of teeth using cone beam CT. METHODS: The sample was composed of 116 cone beam CT scans from Brazilian individuals of both sexes, ranging in age from 13 to 70 years. A total of 232 teeth (upper central incisors and canines) were evaluated. Two calibrated examiners determined pulp cavity volumes using the ITK-SNAP software. Pearson's correlation test was used to assess the correlation between chronological age and pulp volume. Linear and logistic regression models were developed for age and sex estimation, respectively, and were validated in another sample of 72 teeth. RESULTS: Pearson's correlation coefficients between age and pulp volume were negative and significant (p < 0.0001) for both teeth (r = -0.8782 for central incisors and r = -0.8738 for canines). The age estimation formulas showed good determination coefficients (adjusted R² = 0.7614 to 0.8367). For sex estimation, when the age was known, the coefficients were also good (adjusted R² = 0.649 to 0.812). However, when the age was unknown, the coefficients of the sex estimation formulas were low (adjusted R² = 0.047 to 0.393). Validation showed high accuracy of age estimation in individuals older than 35 years, as well as high accuracy of sex estimation when the age was known. CONCLUSIONS: Our formulas provided excellent results and can be applied to the Brazilian population. The best results were observed for age estimation in females and for sex estimation when the age was known.

Evaluation of soft tissues simulant materials in cone beam computed tomography.

OBJECTIVES: To evaluate different materials in simulating soft tissues and to analyze the influence of these materials on the mean (MPIV) and standard deviation of pixel intensity values comparing them to a gold-standard in CBCT images. METHODS: Images of three piglet heads with their soft tissues intact (gold-standard) and different simulant materials were acquired: ice, modelling wax, and ballistic gelatin, with the same thickness of the original soft tissues. The pixel intensities were measured in dental, bone and soft tissues regions, in the mandible and maxilla, for all the groups. Analysis of variance, Dunnet's, Pearson's and linear regression tests were performed. RESULTS: The simulators did not significantly change the MPIV of teeth in comparison with the gold-standard (p = 0.1017). Only ice (p = 0.0156) affected the MPIV of bone. Wax (p = 0.001) and ice (p = 0.0076), but not ballistic gelatin (p = 0.5814), altered the MPIV of soft tissue regions. When assessing the influence of the location (mandible or maxilla) among the simulants, the differences were significant only for the soft tissue regions. Standard deviation was not influenced by simulants (p > 0.05), but ballistic gelatin presented the lower variability. CONCLUSIONS: The ballistic gelatin was the best soft tissue simulant since it had the lowest influence on the pixel intensity values for all regions.

Effects of lidocaine and the inclusion complex with 2-hydroxypropyl-ß-cyclodextrin on cell viability and proliferation of oral squamous cell carcinoma.

OBJECTIVES: Squamous cell carcinoma (SCC) is a malignant disease that affects the oral cavity. Lidocaine has shown antiproliferative and cytotoxic activity on several cell types. The rapid dispersion is a limitation issue; however, the complexation in cyclodextrin improved pharmacological features and modified the drug release. This study investigated the effects of lidocaine (lido) complexed with 2-hydroxypropyl-ß-cyclodextrin (HP-ß-CD-lido) on cell viability and proliferation of human tongue squamous cell carcinoma SCC9 and SCC25. METHODS: The complex formation was confirmed by differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). Cells SCC9 and SCC25 were exposed to lido and HP-ß-CD-lido (40-4000 µm), and the effects on cell viability (MTT) and antiproliferative activity (SRB) were tested. KEY FINDINGS: Differential scanning calorimetry and SEM results demonstrated the occurrence of host-guest interaction. Lido and HP-ß-CD-lido (4000 µm) significantly reduced the viability of SCC9 cells to 83% and 63%, respectively. The viability of SCC25 treated with lido, and HP-ß-CD-lido (4000 µm) was 71% and 44%, respectively. Lido (4000 µm) reduced the proliferation of SCC9 and SCC25 to 39.5% and 23.7%, respectively. HP-ß-CD-lido (4000 µm) was cytotoxic for both cell lines. CONCLUSIONS: HP-ß-CD was able to potentiate the in vitro cytotoxic effects of lidocaine on human squamous cell carcinoma.

Periodontal Status in Morbidly Obese Patients With and Without Obstructive Sleep Apnea Syndrome Risk: A Cross-Sectional Study.

BACKGROUND: This cross-sectional study aims to investigate the correlation between obstructive sleep apnea syndrome (OSAS) risk with periodontal disease and anthropometric measures in Class III obese patients. METHODS: Anthropometric measurements were taken from 108 patients of both sexes, aged 30 to 60 years. The Berlin questionnaire (Bq) and the Epworth sleepiness scale (ESS) were applied to determine the risk for OSAS. Full-mouth periodontal status was determined by probing depth, clinical attachment level, gingival bleeding index, and the presence of calculus. Unpaired Student t, χ(2), Fisher exact, and Mann-Whitney U tests were applied to analyze the differences between high and low risk for OSAS groups. RESULTS: Overall, 81.5% of the patients showed high risk for OSAS, 46.3% had excessive daytime sleepiness, 41.5% were positive for both the Bq and ESS, and 97.2% had periodontal disease (periodontitis = 85.2% and gingivitis = 60.2%). Patients with periodontal disease showed high risk for OSAS (82.9%) and ESS (45.7%). However, there was no influence of periodontal disease on OSAS risk. Periodontitis was not associated with the ESS (odds ratio [OR] = 1.84, 95% confidence interval [CI] = 0.54 to 6.26) or Bq (OR = 0.87, 95% CI = 0.10 to 7.84), nor was gingivitis associated with the ESS (OR = 1.25, 95% CI = 0.48 to 3.25) or Bq (OR = 0.23, 95% CI = 0.03 to 1.84). Waist circumference (P = 0.03), neck circumference (NC, P <0.001), and the percentage of predicted NC (PPNC, P <0.001) were significantly larger in the patients at high risk for OSAS than in those at low risk for OSAS. Daytime sleepiness was also associated with NC (P = 0.02) and PPNC (P = 0.02). CONCLUSION: There was no association between periodontal disease and OSAS risk in Class III obese patients, but OSAS risk was associated with both NC and PPNC.

Assessment of Volume and Height of the Coronoid Process in Patients With Different Facial Types and Skeletal Classes: A Cone-Beam Computed Tomography Study.

PURPOSE: To determine the height and volume of the mandibular coronoid process (CP) by cone-beam computed tomography (CBCT) and to identify the presence of any correlations of these measurements with age, gender, facial type, and skeletal class. MATERIALS AND METHODS: The sample consisted of 132 patients from a departmental routine patient base. After CBCT, CP height was determined using OnDemand 3D software (CyberMed, Seoul, Republic of Korea), and CP volume was obtained using ITK-SNAP 3.0 software (Cognitica, Philadelphia, PA). Measurements were subjected to analysis of covariance against facial type, skeletal class, gender, and age, with a significance level of 5%. RESULTS: CP height and volume were similar regardless of age, facial type, and skeletal class. However, the 2 measurements were statistically different regarding gender, with larger values for men than for women. CONCLUSIONS: These observations suggest that gender is the only factor influencing the height and volume of the CP.

The influence of altered occlusion on pro-inflammatory cytokine levels in the TMJ synovial tissues of rats.

OBJECTIVE: The aim of this study was to evaluate whether altered occlusion affects both the condylar cartilage thickness and the cytokine levels of the TMJs of rats. DESIGN: Thirty adult-male rats (n=30) were randomly assigned to three experimental conditions: a control group that underwent sham operations with unaltered occlusion; an FPDM group that underwent functional posterior displacement of the mandible that was induced by an incisor guiding appliance; and an iOVD group in which the increased occlusal vertical dimension was induced in the molars. The rats were subjected to the FPDM or iOVD model for 14 days and then killed. Both the right and left TMJs were removed and randomly assigned to examination with staining or immunoassay techniques. Toluidine blue staining was used to measure the thicknesses of the four layers of the articular cartilage (i.e., the fibrous, proliferating, mature, and hypertrophic layers). ELISA assays were used to assess the concentrations of the pro-inflammatory cytokines IL-1α, IL-1ß, IL-6, and tumour necrosis factor (TNF-α). The measurements of the articular cartilage layers and cytokine concentrations were analyzed with ANOVA and Tukey's tests and Kruskal-Wallis and Dunn tests, respectively (α=5%). RESULTS: The thickness of articular cartilage in the FPDM group (0.3±0.03mm) was significantly greater than those of the control (0.2±0.01mm) and iOVD (0.25±0.03mm) groups. No significant difference was observed between the control and iOVD groups. The four articular cartilage layers were thicker in the FPDM group than in the control and iOVD groups, and the latter two groups did not differ one from each other. Both the FPDM and iOVD groups exhibited higher cytokine levels than did the control (p<0.05) group. Compared to the FPDM group, the iOVD group exhibited significantly higher levels of IL-1ß and TNF-α. CONCLUSION: Both models induced inflammation in the TMJ and caused significant structural changes in the TMJ and surrounding tissues.

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.

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

OBJECTIVES: 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. METHODS: In this randomized cross-over study with a 1-week washout period, 13 volunteers randomly received one (a single oral dose of 750 mg Mtz (Flagyl®--tablet) and 2) 3 g of 15% Mtz benzoate gel (applied by using a dental tray). The HPLC with ultraviolet detection was used to quantify plasma and saliva concentrations of Mtz. The pharmacokinetic parameters (PPs) areas under the curves from 0 to 48 h (AUC0-48) and from 0 to infinity (AUC0-∞), the maximum plasma concentration (C(max)), the time to C(max), volume of distribution and renal clearance were determined for Mtz tablet. KEY FINDINGS: Considering the Mtz tablet, plasma showed higher Mtz concentration from 6 to 24 h after drug administration and the highest values concerning AUC0-48 h and AUC0-∞ than those obtained in saliva (P < 0.05). No significant differences were observed between plasma and saliva concentrations for Mtz gel. CONCLUSIONS: The study showed that some PPs were higher in plasma (P < 0.05) than in saliva concerning Mtz tablet. Gel formulation had similar Mtz bioavailability in plasma and saliva resulting in systemic absorption.

Micro and nanosystems for delivering local anesthetics.

INTRODUCTION: One of the most common strategies for pain control during and after surgical procedures is the use of local anesthetics. Prolonged analgesia can be safely achieved with drug delivery systems suitably chosen for each local anesthetic agent. AREAS COVERED: This review considers drug delivery formulations of local anesthetics designed to prolong the anesthetic effect and decrease toxicity. The topics comprise the main drug delivery carrier systems (liposomes, biopolymers, and cyclodextrins) for infiltrative administration of local anesthetics. A chronological review of the literature is presented, including details of formulations as well as the advantages and pitfalls of each carrier system. The review also highlights pharmacokinetic data on such formulations, and gives an overview of the clinical studies published so far concerning pain control in medicine and dentistry. EXPERT OPINION: The design of novel drug delivery systems for local anesthetics must focus on how to achieve higher uploads of the anesthetic into the carrier, and how to sustain its release. This comprehensive review should be useful to provide the reader with the current state-of-art regarding drug delivery formulations for local anesthetics and their possible clinical applications.

Inhibition of matrix metalloproteinase-9 activity by doxycycline ameliorates RANK ligand-induced osteoclast differentiation in vitro and in vivo.

Tetracycline antibiotics, including doxycycli\e (DOX), have been used to treat bone resorptive diseases, partially because of their activity to suppress osteoclastogenesis induced by receptor activator of nuclear factor kappa B ligand (RANKL). However, their precise inhibitory mechanism remains unclear. Therefore, the present study examined the effect of Dox on osteoclastogenesis signaling induced by RANKL, both in vitro and in vivo. Although Dox inhibited RANKL-induced osteoclastogenesis and down-modulated the mRNA expression of functional osteoclast markers, including tartrate-resistant acid phosphatase (TRAP) and cathepsin K, Dox neither affected RANKL-induced MAPKs phosphorylation nor NFATc1 gene expression in RAW264.7 murine monocytic cells. Gelatin zymography and Western blot analyses showed that Dox down-regulated the enzyme activity of RANKL-induced MMP-9, but without affecting its protein expression. Furthermore, MMP-9 enzyme inhibitor also attenuated both RANKL-induced osteoclastogenesis and up-regulation of TRAP and cathepsin K mRNA expression, indicating that MMP-9 enzyme action is engaged in the promotion of RANKL-induced osteoclastogenesis. Finally, Dox treatment abrogated RANKL-induced osteoclastogenesis and TRAP activity in mouse calvaria along with the suppression of MMP9 enzyme activity, again without affecting the expression of MMP9 protein. These findings suggested that Dox inhibits RANKL-induced osteoclastogenesis by its inhibitory effect on MMP-9 enzyme activity independent of the MAPK-NFATc1 signaling cascade.

Efficacy of liposome-encapsulated mepivacaine for infiltrative anesthesia in volunteers.

This blinded crossover study evaluated the efficacy and pain sensitivity evoked by a previously reported liposome-encapsulated mepivacaine formulation (Araujo et al., 2004). Thirty healthy volunteers received an intraoral injection (1.8 mL), at four different sessions, of the following formulations: 2% mepivacaine with 1:100,000 epinephrine (MVC(2%EPI)), 3% mepivacaine (MVC(3%)), and 2 and 3% liposome-encapsulated mepivacaine (MVC(2%LUV) and MVC(3%LUV)). Latency period and duration of anesthesia were assessed by an electrical pulp tester and injection discomfort by a visual analog scale (VAS). Data were analyzed with Tukey-Kramer and Friedman tests (P < 0.05). No significant difference was found regarding latency period (in minutes) among the formulations (P > 0.05). The duration of anesthesia after the injection of MVC(3%LUV) was higher than the one obtained after the infiltration of MVC(2%LUV) and of MVC(3%) (P < 0.05). However, the duration of anesthesia obtained with MVC(3%) did not differ from the one obtained with MVC(2%LUV) (P > 0.05). MVC(3%LUV) showed lower VAS median values than MVC(2%EPI) (P < 0.05), and there were no significant differences among the others formulations. Liposome-encapsulated 3% mepivacaine showed longer duration of anesthesia, in comparison to the commercial formulation of MVC(3%). MVC(2%LUV) was able to produce a similar duration of anesthesia as the 3% commercial formulation, despite the 50% decrease in the anesthetic concentration. Thus, the encapsulation of mepivacaine increased the duration of anesthesia and reduced the injection discomfort caused by vasoconstrictor-associated formulations in healthy volunteers.

Liposome-encapsulated ropivacaine for intraoral topical anesthesia.

OBJECTIVES: This study evaluated the efficacy of liposome-encapsulated 2% ropivacaine in topical anesthesia and its influence on pulpal response. STUDY DESIGN: Forty volunteers received the following topical formulations in the buccal fold of the maxillary lateral incisors region (bilaterally): liposome-encapsulated 2% ropivacaine gel (RL2); 20% benzocaine gel (B20); liposomal placebo gel (LP); and placebo gel (P). Formulations were kept in place for 30 minutes, during which time the teeth were electric pulp tested every 10 minutes. After this procedure, a dental needle was inserted until periosteum contact in the same site of topical application and pain was rated by a visual analog scale. Duration of soft tissue anesthesia was assessed by pinprick test. RESULTS: RL2 and B20 showed lower pain response to needle insertion and longer soft tissue anesthesia then P and LP (P = .0003 and P < .0001, respectively); however, RL2 was not different from B20 (P > .05) regarding those parameters. None of the formulations was able to induce pulpal anesthesia. CONCLUSION: RL2 was as effective as B20 in reducing pain during needle insertion and inducing soft tissue anesthesia; however, neither one was able to induce pulpal anesthesia after a 30-min application.

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.

Liposomal encapsulation improves the duration of soft tissue anesthesia but does not induce pulpal anesthesia.

STUDY OBJECTIVE: To compare the topical and the pulpal anesthesia efficacy of liposomal and plain benzocaine formulations. DESIGN: Double-blinded, randomized crossover study. SETTING: University ambulatory dental center. PATIENTS: 30 ASA physical status I volunteers. INTERVENTIONS: Volunteers received, in three different sessions, topical application of liposome-encapsulated 10% benzocaine (LB10), 10% benzocaine gel (B10), and 20% benzocaine gel (B20) in the right maxillary canine mucobuccal fold. MEASUREMENTS: Pain associated with the needle insertion was rated by visual analog scale (VAS) and the duration of topical anesthesia was recorded. Pulpal anesthesia was evaluated using an electric pulp tester. MAIN RESULTS: VAS values (median, 1st - 3rd quartiles) were 17 cm (11 - 25), 14 cm (3 - 22), and 21 cm (9 - 21) for B10, LB10, and B20, respectively. No differences were noted among the groups (Friedman test; P = 0.58). Soft tissue anesthesia was also not different. The LB10 [10 (8 - 12) min] showed longer soft tissue anesthesia (Friedman test; P < 0.01) than the other agents [B10 = 8 (5 - 10) min, and B20 = 7 (6 - 9) min]. None of the topical benzocaine formulations tested induced pulpal anesthesia. CONCLUSIONS: The encapsulation of benzocaine into liposome increased the duration of soft tissue anesthesia. However, it did not induce pulpal anesthesia.

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.

O objetivo deste estudo foi avaliar a formação do biofilme de Streptococcus mutans crescido em resina restauradora envelhecida e não-envelhecida, submetidas à radiação terapêutica. Sessenta e quatro discos do material restaurador Filtek Supreme foram divididos em 2 grupos: grupo envelhecido (AG) e grupo não-envelhecido (NAG) e cada grupo foi dividido em 4 sub-grupos: não-irradiado e irradiado com 10Gy, 35Gy e 70Gy. O biofilme de S. mutans UA159 foi produzido na superfície de ambos os discos AG e NAG. As unidades formadoras de colônia/mL (UFC/mL) foram avaliadas por ANOVA e teste de Tukey (α=0,05). O grupo AG demonstrou menores quantidades de UFC/mL que o grupo NAG antes da radiação e após a radiação de 10Gy (p<0,05). Os sub-grupos AG irradiados com 35 e 70Gy demonstraram aumento na quantidade de biofilme quando comparado aos não irradiados e irradiados com 10Gy (p<0,05). A exposição à radiação ionizante nas doses terapêuticas promoveu mudanças na aderência bacteriana no material restaurador.

The effect of combined bleaching techniques on oral microbiota.

AIMS: To evaluate the antimicrobial activity of 10% and 37% carbamide peroxide during dental bleaching in three different modes. MATERIALS AND METHODS: This five-week double-blind randomized controlled trial included 32 volunteers assigned to four groups (n = 8). Each group received bleaching agents or placebo as an in-office and at-home treatment. The dental bleaching techniques were: In-office bleaching (37% carbamide peroxide: CP37); at-home bleaching (10% carbamide peroxide: CP10) and the association of both (CP37 and CP10). Saliva samples were collected right before (baseline), right after, 12 hours after, and seven days after the treatment. Counts of total microorganisms, Streptococci, and Mutans streptococci were carried out. Friedman test (alpha = 0.05) was used to compare the microorganism counts. RESULTS: The number of the all oral microorganisms remained stable during all experiment. CONCLUSIONS: No bleaching agent (CP37, CP10 or the combination of both) was able to reduce the oral microorganisms tested.