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Aim: To investigate the effect of ageing on control mechanisms of pulpal microcirculation using wavelet analysis and to calculate linear and nonlinear parameters of blood flow oscillations, in a healthy general population., Methodology: Pulpal blood flow (PBF) oscillations were recorded on right maxillary central incisors using laser Doppler Flowmeter (PeriFlux PF 5001, Perimed, Jarfalla, Sweden) on a group of 10 young participants (20-25 years) and a group of 10 older adults (60-70 years). In total, 20 recordings were obtained for at least 20 min (one recording on one tooth per subject). Using wavelet spectral analysis, the amplitude and power were calculated as a linear and Hurst exponent as a nonlinear parameter of PBF oscillations. Differences between the two groups were assessed with the independent Student t-test., Results: Mean PBF levels were significantly lower (P = 0.024) in older adults than in young participants. Relative amplitudes and powers corresponding to the myogenic (P = 0.046, P < 0.001, respectively) and neurogenic activity (P = 0.04, P = 0.01, respectively) were significantly higher, whereas values corresponding to the endothelial function (P = 0.04, P = 0.01, respectively) were significantly lower in older adults than in young participants. Hurst exponents of the total spectrum, myogenic and endothelial component (P < 0.001, P = 0.02, P < 0.001, respectively) of PBF oscillations were significantly lower in older adults in comparison to young participants., Conclusions: At the level of pulpal microcirculation, ageing was associated with altered blood flow levels, the contribution of different control mechanisms to blood flow oscillations as well as the interaction of vascular smooth muscle and endothelium. Described changes of pulpal haemodynamics contribute to a better understanding of physiological behaviour and decreased adaptability of aged dental pulp to pathological stimuli., (© 2020 International Endodontic Journal. Published by John Wiley & Sons Ltd.)

Introduction: Age-related changes of dental pulp tissue and atherosclerosis of carotid arteries as its feeding arteries could influence the functionality of pulpal circulation. The objective of our study was to evaluate the effect of aging (physiological process) and carotid bifurcation atherosclerosis (pathologic process) on the pulpal microcirculatory system using multifractal analysis of the laser Doppler flowmetry signal., Methods: Three groups of 10 subjects were enrolled in the study: the young group (healthy subjects, 20-25 years), the middle-aged group (healthy subjects, 50-60 years), and the clinical group (subjects with carotid bifurcation atherosclerosis, 50-60 years). Pulpal blood flow (PBF) signals recorded by laser Doppler flowmetry were assessed by multifractal analysis that estimates Hölder exponents of the signal. PBF levels, the average mean values, and the range of Hölder exponents were obtained., Results: PBF levels were significantly higher in the young group compared with the middle-aged and clinical groups, and the difference between the middle-aged and clinical groups was not statistically significant. The range of the Hölder exponents was narrower in the middle-aged and clinical groups than in the young group and narrower in the clinical group than in the middle-aged group. The average mean value of Hölder exponents was significantly higher in the young group than in the middle-aged and clinical groups, whereas there was no significant difference between the middle-aged and clinical groups., Conclusions: Our study investigating the multifractality of the PBF signal showed that the aging process and carotid atherosclerosis could affect the complex structure of PBF oscillations and contribute to a better understanding of pulpal hemodynamics., (Copyright © 2020 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

Objective: Stability of blood alcohol concentration (BAC) in laboratory samples is of great importance when it is necessary to perform repeated analyses., Materials and Methods: We have analyzed the stability of BAC in 50 samples, which were taken from apprehended drivers, kept at -18ºC, without preserving agents. Quantitative analyses were performed using headspace sampling gas chromatography (HS-GC) with flame ionizing detection (FID). Samples were analyzed immediately after collection (C1), and after 60 (C60), 120 (C120) and 180 (C180) days. A group of 50 samples, which were kept closed for 180 days at -18ºC, was utilized as a control., Results: We found a significant decrease in BAC between C1 and C180 (= 0.224; SD= 0.144; t = 10.98; p<0.001), and between C1 and C60, C60 and C120, C120 and C180. There was a significant positive correlation (r=0.8) between starting concentration C1, and the value of BAC changes (ΔC). Linear regression analysis (R2=0.64) implies the degree of validity to the proposed model of ΔC change regarding initial BAC. There were significant changes in ΔC between the two groups., Conclusions: These data underline the significance of air chamber percent (CA%) and ethanol evaporation due to ventilation between liquid and gas phase as a mechanism of ethanol decay.

Objectives: The pulpal anesthetic and cardiovascular parameters obtained by 2 % lidocaine with epinephrine (LE; 1:80,000) or clonidine (LC; 15 mcg/ml) were studied in diabetes mellitus (DM) type 2 and healthy volunteers (72), after maxillary infiltration anesthesia., Materials and Methods: Onset and duration of pulpal anesthesia were measured by electric pulp tester; vasoconstrictive effect of used local anesthetic mixtures by laser Doppler flowmetry (LDF) through pulpal blood flow (PBF); systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate (HR) were registered by electrocardiogram monitoring., Results: Onset of pulpal anesthesia was shorter for LC than for LE in healthy, while it was not different in diabetic participants; duration of pulpal anesthesia was significantly longer in type 2 diabetic participants, regardless of used anesthetic mixture. Significant reduction of PBF with LE was observed during 45 min in healthy and 60 min in diabetic participants, while with LC such reduction was observed during 45 min in both groups. LE caused a significant increase of SBP in the 5th and 15th minutes in diabetic versus healthy participants, while LC decreased SBP from the 10th to 60th minutes in healthy versus diabetic participants., Conclusions: DM type 2 influences duration of maxillary infiltration anesthesia obtained with LE and LC, and systolic blood pressure during LE anesthesia., Clinical Relevance: The obtained results provide elements for future protocols concerning intraoral local anesthesia in DM type 2 patients.

Objectives: The main purpose of this prospective, double-blind, randomized study was to evaluate anaesthetic parameters, postoperative analgesia and vasoactive properties of levobupivacaine and bupivacaine for lower third molar surgery., Material and Methods: Sixty patients (ASA I) were scheduled for lower third molar surgery under inferior alveolar nerve block, lingual nerve block and buccal nerve block (mandibular nerve blocks) obtained with 3 ml of 0.5 % levobupivacaine and 3 ml of 0.5 % bupivacaine. Success rate, onset and duration of three nerve bocks were evaluated by electrical pulp testing, pinprick testing and signs of soft tissue anaesthesia (patient-reported numbness). Intensity of intraoperative anaesthesia and postoperative analgesia were measured with visual analogue scale (VAS) and numeric rating scale (NRS). The time of first postoperative pain reported and analgesic consumption were also recorded. The laser Doppler flowmetry was used for the measurement of the first premolar pulpal blood flow., Results: There were no differences between levobupivacaine and bupivacaine regarding the success rate, onset and duration of mandibular nerve blocks as well as intensity of postoperative analgesia and analgesic consumption. Intensity of intraoperative anaesthesia and duration of postoperative analgesia were significantly higher in the levobupivacaine than in the bupivacaine group. Both anaesthetics showed similar biphasic vasoactive effect., Conclusions: Levobupivacaine 0.5 % achieved superiority over bupivacaine 0.5 % in the intensity of intraoperative anaesthesia and duration of postoperative analgesia for lower third molar surgery under the mandibular nerve blocks., Clinical Relevance: It seems that the plain levobupivacaine (0.5 %) could be an effective alternative to plain bupivacaine (0.5 %) in those dental procedures which require profound bone and soft tissue anaesthesia.

Objectives: The main purpose of this study was to evaluate the dose-dependent anesthetic efficacy of the intraseptal anesthesia (ISA) and periodontal ligament anesthesia (PLA) obtained with different volumes of 4 % articaine and 1:100,000 epinephrine (Ar + Ep) in human mandibular premolars, using a computer-controlled local anesthetic delivery system (CCLADS). The safety profile of Ar + Ep was also studied by investigating the stability of cardiovascular parameters., Material and Methods: One hundred and eighty randomly selected healthy volunteers (ASA I) entered the single-blinded study to receive 16 mg + 4 μg, 24 mg + 6 μg, and 32 mg + 8 μg of Ar + Ep, obtained with different volumes (0.4, 0.6, and 0.8 ml, respectively), for the ISA and PLA. Success rate, onset, and duration of profound pulpal anesthesia were evaluated by the electrical pulp tester, while the width of the anesthetic field and duration of soft tissue anesthesia were recorded using the pinprick testing. A monitor was used for the measurement of cardiovascular parameters., Results: A dose-dependent duration of pulpal and soft tissue anesthesia was obtained only by the ISA. Success rate, duration of both pulpal and soft tissue anesthesia, and its width were significantly better in the ISA compared with the PLA. No significant cardiovascular changes were seen in both groups., Conclusions: It can be suggested that 0.6 and 0.8 ml of 4 % Ar + 1:100,000 Ep, delivered by CCLADS, offer high success rate and effective clinical parameters of ISA as a primary anesthesia., Clinical Relevance: It seems that dental procedures requiring profound pulpal, bone, and soft tissue anesthesia could be effectively and safely obtained by mentioned anesthetic protocol.

Introduction: The skin microcirculation is significantly affected by serum estrogen levels. The objective of this study was to investigate the effects of estrogen serum level changes associated with the menstrual cycle and postmenopause on dental pulp blood flow (PBF) as well as its dynamics., Methods: Young women at the menstrual phase (low serum estrogen levels) and in the mid-cycle phase of the menstrual cycle (high serum estrogen levels) and postmenopausal women were enrolled in the study. PBF and its oscillations were measured by laser Doppler flowmetry and analyzed by using wavelet transform. Serum levels of estradiol-17β were measured by immunoassay., Results: PBFs of young women in the menstrual phase and postmenopausal women were mutually similar and significantly lower than those of young women in the mid-cycle period. With respect to the mid-cycle phase, relative amplitude and power were significantly increased in the interval 0.0095-0.02 Hz and decreased in the intervals 0.02-0.06 and 0.06-0.2 Hz in the menstrual phase. A significant decrease in 0.0095-0.02 Hz and increase in 0.02-0.06, 0.06-0.2, 0.2-0.6, and 0.6-1.6 Hz intervals were observed in postmenopause., Conclusions: The study has shown that the menstrual phase of the menstrual cycle and postmenopause have similar PBF decrease, but PBF oscillations are differently affected in the mid-cycle phase., (Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

The main purpose of this study was to assess the clinical efficacy and haemodynamic effects of ropivacaine for infiltration anaesthesia in patients undergoing surgical removal of upper third molars. The safety profile of ropivacaine was also studied by investigating the maximal venous plasma concentration of ropivacaine and the reactivity to ropivacaine of isolated human infraorbital arteries. Ropivacaine in concentrations of 0.5, 0.75 and 1% achieved dose-dependent parameters of maxillary infiltration aneasthesia, clinically relevant in concentrations 0.75 and 1%. Postoperative needs for analgesics were observed in 67-100% of patients. Haemodynamic parameters were stable during surgery with significant changes occuring 10 min after surgery. After maxillary infiltration of 2.0 ml 1% ropivacaine, the maximum venous plasma concentration (Cmax) was 82+/-15 microg/l. On isolated human infraorbital artery, ropivacaine (10(-4)M) induced endothelium-independent contraction. This study suggests that 0.75 and 1% ropivacaine offers adequate and safe intraoperative analgesia but not successful postoperative pain control for the surgical removal of upper third molars., (Copyright 2009 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

The aim of the study was to evaluate the long-term effects of antidepressive therapy on chronic pain and related disability, and masseter silent period in psychiatric depressive patients with temporomandibular disorders (TMD). The study included hospitalized psychiatric depressive patients on antidepressive therapy protocol (tetracyclic antidepressant-maprotiline and anxiolytic-diazepam) (n=30) and non-psychiatric patients seeking prosthodontic treatment (control group, n=38). TMD were diagnosed by Research Diagnostic Criteria for temporomandibular disorders proposed by Dworkin and LeResche. The surface electromyography was recorded from left and right masseter muscles and masseter inhibitory reflex (masseter silent period) was recorded after mechanical stimulation. The incidence of TMD appearance was very similar, of approximately 40% in both group of patients. The results of the study also indicated a higher prevalence of joint related TMD, a lower prevalence of muscular subtype of TMD and a lower grade of chronic pain and related disability in the psychiatric group of patients on antidepressive therapy in comparison with findings in the control group. In the patients on antidepressive therapy with TMD masseter silent period was not prolonged , while in the control group of patients with TMD the prolongation of the silent period was observed. The study provided evidence that long-term, combined therapy (maprotiline and diazepam) in psychiatric depressive patients significantly modulated signs and symptoms of TMD in comparison with the control group.

The local anaesthetic and haemodynamic parameters achieved by lidocaine with clonidine or epinephrine, administered for maxillary infiltration anaesthesia, were studied in 40 patients (American Society of Anesthesiologists, physical status 1) who underwent upper third molar surgery. All patients received 2 ml of 2% lidocaine with clonidine (15 microg/ml; n=20) or epinephrine (12.5 microg/ml; n=20) in a randomized, double-blind fashion. Vascular effects were evaluated on the isolated human infraorbital arteries. The parameters of maxillary infiltration anaesthsia produced by a combination of lidocaine+clonidine were similar to those obtained with lidocaine+epinephrine. In both groups, haemodynamic parameters exhibited similar variations, with the exception of a significant reduction in heart rate and systolic blood pressure in the lidocaine+clonidine group and significant increase in heart rate in the lidocaine+epinephrine group, 10 min after surgery. Clonidine (10(-7), 10(-6) and 10(-5)M) produced an endothelium-independent vasocontractile effect on the isolated human infraorbital arteries. The results of this study indicate for the first time in dental anaesthesia that the lidocaine+clonidine combination could be a useful and safe alternative to lidocaine+epinephrine for intraoral infiltration anaesthesia.

The admixture of clonidine or epinephrine to lidocaine for inferior alveolar nerve block was studied with regard to onset, duration, intensity of anaesthesia, postoperative analgesia, systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), heart rate (HR), ST segment depression > or =1 mm and cardiac arrhythmias. Forty healthy patients (ASA I) received 2 ml 2% lidocaine with clonidine (15 microg/ml; n = 20) or epinephrine (12.5 microg/ml; n = 20) in a double-blind fashion for lower third molar surgery. Duration and intensity were not different between groups, while onset was significantly different by subjective evaluation. The need for postoperative pain medication was significantly lower in the clonidine group. There was a significant decrease in SBP and MAP in both groups 35 min after administration of anaesthesia compared with basal values, while DBP was significantly lower only in the clonidine group. There was no significant difference in SBP, DBP and MAP between groups. HR was significantly increased in the epinephrine group 5 min after administration of anaesthesia and during surgery compared with the clonidine group and with basal values. The presented data suggest that clonidine could be a useful and safe alternative to epinephrine for intraoral block anaesthesia.

The effects of captopril and bradykinin on chorda tympani-induced salivation were studied in the submandibular gland of anesthetized cat. Captopril and bradykinin, but not des-Arg9-bradykinin, increased salivation evoked by electrical stimulation of chorda tympani. These potentiated effects of captopril and bradykinin were suppressed by Hoe-140, a kinin B2 receptor antagonist, or by concomitant addition of N(G)-nitro arginine methyl ester (L-NAME), a nitric oxide synthase inhibitor, and aspirin, a cyclooxygenase inhibitor. It appears that captopril potentiates chorda tympani-induced salivation through endogenously accumulated bradykinin, which acts on kinin B2 receptors, mediating production of nitric oxide and cyclooxygenase products.

A series of periphyton, sediment, and water samples has been collected from the Kolubara River and its tributaries at selected locations, characterized by heavy industrialization, and analysed for stable isotopes by X-ray-fluorescence spectrometry. The results of measurements for stable metals revealed that the anthropogenic contribution essentially overwhelms the natural system of the catchment. Thus, concentrations of heavy metals near points of industrial discharge were significantly higher than background concentrations. The existing primary and secondary waste water-treatment plants associated with heavy industry of the area must therefore be revived, and control should be instituted at the sources of pollution. The bioaccumulation factors (BF), and sediment distribution coefficients (K(D)), and concentration ratios (CR) for sixteen stable isotopes were calculated. It is shown that the concentration ratios of periphyton over sediment for Mn, Zn, As, Sb, I, Ba, and Pb exceeded unity. Furthermore, the recorded partition coefficients were indicative of the distribution and mobility of the stable metals in the Kolubara River environment.

Epinephrine and norepinephrine, but not isoproterenol, stimulated the consumption of oxygen in rat parotid gland slices in a dose dependent manner. Their actions were abolished by phentolamine but propranolol had no effect. The response to epinephrine was selectively blocked by yohimbine, whereas the response to norepinephrine was inhibited by prazosin. Nifedipine abolished the action of epinephrine but had no effect on norepinephrine. The findings suggest that epinephrine enhanced oxygen consumption in the parotid gland slices by the activation of the calcium dependent alpha-2-adrenoreceptors while the response to norepinephrine was mediated by the alpha-1-receptors.