Conventional drilling versus ultrasound and laser osteotomy in mandibular third molar surgery: A comparative study.

BACKGROUND: There are few research works with in-depth studies and direct simultaneous comparisons of the effects on tissue reactions and patients' recovery following in vivo conventional drilling, ultrasound- and laser-assisted osteotomy in humans. OBJECTIVE: The current study aims to compare bone cutting duration, pain, swelling, and trismus in patients following surgical mandible third molar extraction by bone removal using three different osteotomes-a conventional rotary device, an ultrasonic unit, and an Er:YAG laser. METHODS: A prospective, randomized three-group comparative clinical trial was performed. As an experimental setting for the study, аn open mandible third molar surgery was chosen because osteotomy is included in its protocol. Patients were divided into three groups according to the used device for bone removal. Bone cutting time intraoperatively, facial swelling, trismus, and pain on the first, second, and third postoperative days were assessed. The statistical analyses were performed using the SPSS v. 17.0-Kolmogorov-Smirnov test, one-way ANOVA, Student's t-test, Mann-Whitney test, and χ2  test. Statistical results were considered significant at p < 0.05 (confidence interval of difference, 95% CI). RESULTS: Eighty patients (34 males and 46 females with an average age of 25.18 years) were included in the study. The average time for bone removal by the conventional low-speed device (4.95 min), by the ultrasonic unit (5.13 min), and by the Er:YAG laser (9.00 min) differed significantly (p = 0.001). The mean postoperative facial swelling showed a marked difference between the groups (p < 0.05), in favor of the laser and piezo groups. The osteotome proved to influence pain intensity not only immediately after surgery (p = 0.002), but also during the followed-up period (p = 0.001), again in favor of the two above-mentioned groups. No association was found between trismus and the osteotome used by the followed-up patients (p > 0.05). CONCLUSION: Bone-cutting mechanism and the biological influence of the laser beam and ultrasound on living tissues proved to be favorable factors for patients' pain levels and tissue swelling postoperatively independent of the longer osteotomy duration compared to conventional drilling.

The Endogenous Cannabinoid and the Nitricoxidergic Systems in the Modulation of Stress Responses.

The effects on stress-induced analgesia (SIA) from endogenous cannabinoid system (ECS) and nitric oxide (NO) interaction after 1 h of restraint stress were evaluated in male Wistar rats. The animals were subjected to 1 h of restraint and then injected with different combinations of cannabinoid receptor type 1 agonist anandamide (AEA) or antagonist AM251 along with an NO donor, NO precursor, or inhibitor of NO synthase. Nociception was evaluated using paw pressure (PP) or hot plate (HP) tests. AEA was administered immediately after the end of restraint-SIA (r-SIA). Administration of NO precursor reversed the pronociceptive effect of the CB1 agonist on r-SIA. Both the CB1 antagonist and the NOS inhibitor neutralized the pro-analgesic effect of L-arginine (L-arg). Administration of an NO donor, instead, increased r-SIA. Our experiments confirmed that the endogenous cannabinoid and the NO-ergic systems interact in the modulation of r-SIA. This interaction probably implies NO as a second messenger of the ECS.

Effect of Quercetin and Fingolimod, Alone or in Combination, on the Sphingolipid Metabolism in HepG2 Cells.

Combinations of anti-cancer drugs can overcome resistance to therapy and provide new more effective treatments. In this work we have analyzed the effect of the polyphenol quercetin and the anti-cancer sphingosine analog fingolimod on the sphingolipid metabolism in HepG2 cells, since sphingolipids are recognized as mediators of cell proliferation and apoptosis in cancer cells. Treatment of hepatocellular carcinoma HepG2 cells with quercetin and fingolimod, alone or in combination, induced different degrees of sphingomyelin (SM) reduction and a corresponding activation of neutral sphingomyelinase (nSMase). Western blot analysis showed that only treatments containing quercetin induced up-regulation of nSMase expression. The same treatment caused elevation of ceramide (CER) levels, whereas the observed alterations in sphingosine (SPH) content were not statistically significant. The two tested drugs induced a reduction of the pro-proliferative sphingolipid, sphingosine 1 phosphate (S1P), in the following order: quercetin, fingolimod, quercetin + fingolimod. The activity of the enzyme responsible for CER hydrolysis, alkaline ceramidase (ALCER) was down-regulated only in the incubations involving quercetin and fingolimod did not affect this activity. The enzyme, maintaining the balance between apoptosis and proliferation, sphingosine kinase 1 (SK1), was down-regulated by incubations in the following order: quercetin, fingolimod, quercetin + fingolimod. Western blot analysis showed down-regulation in SK1 expression upon quercetin but not upon fingolimod treatment. Studies on the effect of quercetin and fingolimod on the two proteins associated with apoptotic events, AKT and Bcl-2, showed that only quercetin, alone or in combination, down-regulated the activity of the two proteins. The reported observations provide information which can be useful in the search of novel anti-tumor approaches, aiming at optimization of the therapeutic effect and maximal preservation of healthy tissues.

Radioprotective effect of Rapana thomasiana hemocyanin in gamma induced acute radiation syndrome.

The radioprotective effect of Rapana thomasiana hemocyanin (RtH) against radiation-induced injuries (stomach ulcers, survival time and endogenous haemopoiesis) and post-radiation recovery was investigated in male albino mice (C3H strain). Radiation course was in a dose of 7.5 Gy (LD 100/30 - dose that kills 100% of the mice at 30 days) from 137Cs with a dose of 2.05 Gy/min. Radiation injuries were manifested by inducing а hematopoietic form of acute radiation syndrome. RtH was administered intraperitoneally in a single dose of 50, 100, 150 and 200 mg/kg body weight (b. w.) once a day for five consecutive days before irradiation. The results obtained showed that radiation exposure led to (1) 100% mortality rate, (2) ulceration in the stomach mucosa and (3) decrease formation of spleen colonies as a marker of endogenous haemopoiesis. Administration of RtH at a dose of 200 mg/kg provided better protection against radiation-induced stomach ulceration, mitigated the lethal effects of radiation exposure and recovered endogenous haemopoiesis versus irradiated but not supplemented mice. It could be expected that RtH will find a use in mitigating radiation induced injury and enhanced radiorecovery.

Tissue changes and tissue reactivity following osteotomy by a conventional rotary device, an ultrasonic unit, and an Er: YAG laser - A comparative study in humans.

INTRODUCTION: Innovative technologies from other fields of science are constantly being introduced in medicine. Research works on animals strongly confirm the belief in better results following ultrasound and laser surgery. The main conclusions are based on observations from different animal species, whose biological characteristics differ from those of humans. This requires scientific experiments to be performed and confirmed in humans. MATERIAL & METHODS: Human mandible specimens harvested in vivo by a conventional low-speed rotary device, an ultrasonic unit, or an Er: YAG laser were studied and analyzed to compare their effects on bone morphology and tissue response following surgery. RESULTS: The cutting surface of eighty biopsies was studied, as well the facial edema, pain levels, and jaw dysfunction were followed up in the same eighty patients from whom the slices were obtained. In the piezosurgery and drill groups, the borders exhibited irregular edges full of bone fragments and debris. Thermal alterations within the superficial surface in all bone samples were generally minimal. In all specimens, intact osteocytes were detectable away from the area of direct action of the bone-cutting device. It was established, that the reactive facial edema, pain levels, and jaw disfunction were with milder values following in vivo osteotomy by an ultrasonic unit and Er: YAG laser compared to the conventional drilling. Moreover, the recovery of the patients in these two groups was more pronounced. The observed tissue changes proved to affect the follow-up tissue reactions in the postoperative period (p ≤ 0.05). DISCUSSION: Based on the established effects on human bone by its in vivo cutting, it can be concluded that laser and ultrasonic bone surgery was a superior alternative osteotomy method in humans to conventional drilling.

Cannabinoid and Serotonergic Systems: Unraveling the Pathogenetic Mechanisms of Stress-Induced Analgesia.

The perception of "stress" triggers many physiological and behavioral responses, collectively called the stress response. Such a complex process allows for coping with stress and also triggers severe pathology. Because of the multidirectional effect of stress on the body, multiple systems participate in its pathogenesis, with the endogenous cannabinoid and the serotoninergic ones among them. These two systems also take part in the pain perception decrease, known as stress-induced analgesia (SIA), which can then be taken as an indirect indicator of the stress response. The aim of our study was to study the changes in cold SIA (c-SIA) resulting from the exogenous activation of cannabinoid receptor type 1 (CB1) and 5-hydroxytryptamine (5-HT, serotonin) receptor type 1A (5-HT1A). Various combinations of agonists and/or antagonists of CB1 and 5-HT1A, before or after 1 h of cold exposure, were applied, since we presumed that the exogenous activation of the receptors before the cold exposure would influence the pathogenesis of the stress response, while their activation after the stressful trigger would influence the later development. Our results show that the serotonergic system "maintained" c-SIA in the pre-stress treatment, while the cannabinoids' modulative effect was more prominent in the post-stress treatment. Here, we show the interactions of the two systems in the stress response. The interpretation and understanding of the mechanisms of interaction between CB1 and 5-HT1A may provide information for the prevention and control of adverse stress effects, as well as suggest interesting directions for the development of targeted interventions for the control of specific body responses.

Antiviral Activity of Rosa damascena Mill. and Rosa alba L. Essential Oils against the Multiplication of Herpes Simplex Virus Type 1 Strains Sensitive and Resistant to Acyclovir.

BACKGROUND: The specific chemotherapeutics against herpes simplex virus type 1 (HSV) are nucleoside analogues such as acyclovir (ACV), but the most important problem is the formation of resistant mutants. The search for new therapeutic alternatives leads us to the purpose of investigating the effects of Rosa damascena Mill. and Rosa alba L. essential oils on the viral reproduction of susceptible (Victoria) and acyclovir-resistant (R-100) strains of HSV-1 replication in vitro, individually and in combination with acyclovir. METHODS: Cytopathic effect inhibition test was used for assessment of antiviral activity of the oils, and the three-dimensional model of Prichard and Shipman was applied to evaluate the combined effect of oils with ACV on HSV-1 replication. RESULTS: Both oils do not affect the replication of viral strains; they are able to influence only viral adsorption and extracellular virions and protect healthy cells from subsequent infection. In combination with lower doses of acyclovir, both oils demonstrate a significant synergistic effect on the replication of HSV-1, which is more contagious than the Victoria strain. CONCLUSIONS: The nonspecific mechanism of the reduction in viral reproduction caused by rose oils and the synergistic effect of their co-administration with the lower doses of specific inhibitor ACV makes them suitable therapeutics for overcoming viral resistance to HSV-1 infections.

Oseltamivir and S-Adenosyl-L-Methionine Combination as Effective Therapeutic Strategy for Suppression of Oxidative Damage in Lung Caused by Influenza Virus Infection in Mice.

BACKGROUND AND OBJECTIVES: The pathogenesis of influenza infection is associated with two general processes in the body: (a) lung damage based on virus replication; (b) overproduction of free radicals, antioxidant deficiency, and development of oxidative stress. To attack these aspects of flu pathogenesis, we explored the combined effect of the antiviral agent oseltamivir, and s-adenosyl-l-methionine (SAM) as a precursor of the endogenous antioxidant glutathione, in mice infected with influenza virus. METHODS: After inoculation of albino mice with 10 MLD50 of influenza virus A/Aichi/2/68 (H3N2), oseltamivir was applied twice a day, for five days post-infection in doses of 1.25 and 2.5 mg/kg. SAM was administered once a day for 10 days, starting 5 days before infection in doses of 50, 100 and 150 mg/kg. RESULTS: Monotherapy with SAM did not influence the markers of oxidative stress in the lung. Combination of SAM 50 mg/kg and oseltamivir 2.5 mg/kg affected best the virological parameters - viral titer, protection index, and mean survival time, as well as the biochemical markers of oxidative stress. INTERPRETATION AND CONCLUSIONS: Combining of SAM and oseltamivir in a dose of 1/4 of optimal therapeutic could be considered as a perspective therapy of influenza viral infection.

Cytoarchitectonic study of the trigeminal ganglion in humans.

The trigeminal ganglion (TG), a cluster of pseudounipolar neurons, is located in the trigeminal impression of the temporal pyramid. It is covered by a sheath of the dura mater and arachnoid and is near the rear end of the cavernous sinus. The peripheral processes of the pseudounipolar cells are involved in the formation of the first and second branch and the sensory part of the third branch of the fifth cranial nerve, and the central ones form the sensory root of the nerve, which penetrates at the level of the middle cerebellar peduncle, aside from the pons, and terminate in the sensory nuclei of the trigeminal complex. We found that the primary sensory neurons involved in sensory innervation of the orofacial complex are a diverse group. Although they possess the general structure of pseudounipolar neurons, there are significant differences among them, seen in varying intensities of staining. Based on our investigations we classified the neurons into 7 groups, i.e. large, subdivided into light and dark, medium, also light and dark, and small light and dark, and, moreover, neurons with an irregular shape of their perikarya. Further research by applying various immunohistochemical methods will clarify whether differences in the morphological patterns of the neurons are associated with differences in the neurochemical composition of various neuronal types.

Abnormal attachments between a plantar aponeurosis and calcaneus.

BACKGROUND AND AIMS: The plantar aponeurosis or fascia is a thick fascial seal located on the lower surface of the sole. It consists of three parts central, lateral, and medial. The central portion is the thickest. It is narrow behind and wider in front. The central portion has two strong vertical intermuscular septa which are directed upward into the foot. The lateral and medial portions are thinner. The medial portion is thinnest. The lateral portion is thin in front and thick behind. The main function of the plantar fascia is to support the longitudinal arch of the foot. In May 2013 during a routine dissection in the section hall of the Department of Anatomy and Histology in Medical University - Sofia, Bulgaria we came across a very interesting variation of the plantar aponeurosis. MATERIALS AND METHODS: For the present morphological study tissues from a human corpse material were used. This unusual anatomical variation was photographed using a Nikon Coolpix 995 camera with a 3.34 Megapixels. RESULTS: We found some fibrous strands which started from the proximal portion of the plantar aponeurosis on the left foot. The fibrous strands resembled the tentacles of an octopus and started from the proximal portion of the aponeurosis. Two of fibrous strands were directed laterally to adipose tissue and one was directed medially and backward. The first lateral fibrous strand was divided into several fascicles. We found very few data in literature about the varieties of the plantar fascia. CONCLUSION: It is very important to consider the occurrence of above mentioned variations in the plantar aponeurosis when surgical procedures are performed on the sole.

A rare variation of the digastric muscle.

The digastric muscle is composed by two muscle bellies: an anterior and a posterior, joined by an intermediate tendon. This muscle is situated in the anterior region of the neck. The region between the hyoid bone and the mandible is divided by an anterior belly into two triangles: the submandibular situated laterally and the submental triangle which is located medially. We found that the anatomical variations described in the literature relate mainly to the anterior belly and consist of differences in shape and attachment of the muscle. During routine dissection in February 2013 in the section hall of the Department of Anatomy and Histology in Medical University - Sofia we came across a very interesting variation of the digastric muscle. The digastric muscles that presented anatomical variations were photographed using a Sony Cyber-shot DSC-T1 camera, with a Carl Zeiss Vario-Tessar lens. We found out bilateral variation of the digastric muscle in one cadaver. The anterior bellies were very thin and insert to the hyoid bone. Two anterior bellies connect each other and thus they formed a loop. The anatomical variations observed of our study related only to the anterior belly, as previously described by other authors. It is very important to consider the occurrence of the above mentioned variations in the digastric muscle when surgical procedures are performed on the anterior region of the neck.