Surgical management of impacted primary teeth: report of two cases.

AIM: Impaction of deciduous teeth is an uncommon event. The purpose of this report is to describe two unusual eruption failures of a second primary molar and their treatment management. CASE REPORT: The diagnostic and therapeutic protocol of two cases selected at the Unit of Paediatric Dentistry, Department of Oral and Maxillofacial Science, "Sapienza" University of Rome, Italy, are presented. In both cases, the second deciduous molar was impacted, while no mechanical obstacle like odontomas or supernumerary teeth were present. CONCLUSION: The two case reports presented in this work are of scientific relevance, due to the rarity of this type of pathology.

Influence of alkoxy chain envelopes on the interfacial photoinduced processes in tetraarylporphyrin-sensitized solar cells.

The introduction of alkoxy chains in the molecular architecture of meso push-pull porphyrins is of paramount importance aiming at high performing dye-sensitized solar cells (DSSCs) based on these specific sensitizers. Recently, we have demonstrated that the same approach is fruitful even if it is applied to tetraarylporphyrins with an acceptor/anchoring substituent in the ß-pyrrolic position. In particular, among the ortho-ortho, the ortho-para and the ortho-functionalization of the aryl rings with an octyloxy chain, we identified the latter as the most performing in the series, showing a good balance between the dye loading and the reduction of π-π aggregation. Herein, focusing our attention on the mono-ortho-functionalized molecular structure, we have investigated the effect of the alkoxy chain length and nature on the reduction of dye-to-dye aggregation as well as on the enhancement of light harvesting capabilities, finding an almost linear relationship between the device photon conversion efficiency (PCE) and the alkoxy chain length both in the presence and in the absence of a co-disaggregating agent.

The relationship between upper airways and craniofacial morphology studied in 3D. A CBCT study.

OBJECTIVES: To assess whether morphology and dimension of the upper airway differ between patients characterized by various craniofacial morphology. SETTING AND SAMPLE POPULATION: Ninety young adult patients from the Postgraduate Clinic, Section of Orthodontics, Department of Dentistry, Health, Aarhus University, Denmark, with no obvious signs of respiratory diseases and no previous adeno-tonsillectomy procedures. Thirty patients were characterized as Class I (-0.5 < ANB < 4.5), 30 as Class II (ANB > 4.5), and 30 as Class III (ANB < -0.5). MATERIAL AND METHODS: Cone-beam computed tomography (CBCT) scans obtained in a supine position for all patients. Cephalometric landmarks were identified in 3D. Sagittal and transversal dimensions, cross sections, and partial and total volumes of the upper airway were correlated with the cephalometric measurements in all three planes of space. The cross-sectional minimal area of the upper airway was assessed as well. RESULTS: No statistical significant relationships between dimension and morphology of upper airways and skeletal malocclusion were found. CONCLUSION: Differences in craniofacial morphology as identified by the sagittal jaw relationship were not correlated with variation in upper airway volumes. A clinical significant relation was detected between minimal area and total upper airway volume.

Er:YAG laser for brackets bonding: a SEM study after debonding.

BACKGROUND: The introduction of Er:YAG laser in dentistry for ablation of hard tissues advocated an alternative method of enamel etching for orthodontics purpose. MATERIALS AND METHODS: 55 extracted human third molars were inserted in acrylic resin blocks and divided into five groups of 11 teeth. Group 1 was treated with 37% orthophosphoric acid for 30 seconds. Group 2 was treated with laser irradiation (Er:YAG Fidelius III, Fotona, Slovenia) at 80 mJ and 4 Hz. Group 3 underwent laser treatment (80 mJ, 4 Hz), followed by 37% orthophosphoric acid for 30 seconds. The teeth in Group 4 were treated with laser at 40 mJ and 10 Hz. The teeth in Group 5 were treated with laser (40 mJ, 10 Hz), followed by 37% orthophosphoric acid for 30 seconds. The adhesive remnant index was determined after debonding. RESULTS: Kruskas-Wallis test showed that location parameters (median and mean) are significantly different between Groups 2 and 4 when compared with control group; on the contrary no significant difference was detected between Groups 3 and 5 with the controls. CONCLUSION: The use of Er:YAG laser alone, as in Groups 2 and 4, showed no significant advantages over phosphoric acid in the bonding procedure for orthodontics brackets.

Marsupialization of radicular cyst in a 9-year-old child: report of a case and review of the literature.

The following report describes the treatment of a 9-year-old child affected by a radicular cyst. The case was treated through the extraction of the impacted primary tooth followed by marsupialization. The residual cystic cavity was filled with a removable device in order to speed the healing process, facilitate the eruption of the permanent teeth and avoid orthodontic treatment. This technique is suitable as conservative treatment for patients affected by radicular cyst.

Heterogeneous catalytic degradation of phenolic substrates: catalysts activity.

This review article explored the catalytic degradation of phenol and some phenols derivates by means of advanced oxidation processes (AOPs). Among them, only the heterogeneous catalyzed processes based on catalytic wet peroxide oxidation, catalytic ozonation and catalytic wet oxidation were reviewed. Also selected recent examples about heterogeneous photocatalytic AOPs will be presented. In details, the present review contains: (i) data concerning catalytic wet peroxide oxidation of phenolic compounds over metal-exchanged zeolites, hydrotalcites, metal-exchanged clays and resins. (ii) Use of cobalt-based catalysts, hydrotalcite-like compounds, active carbons in the catalytic ozonation process. (iii) Activity of transition metal oxides, active carbons and supported noble metals catalysts in the catalytic wet oxidation of phenol and acetic acid. The most relevant results in terms of catalytic activity for each class of catalysts were reported.

Obstructive sleep apnea syndrome in the pediatric age: the role of the dentist.

OBJECTIVE: Sleep disordered breathing in children designates a wide spectrum of respiratory disorders characterized by partial or complete obstruction of the upper airways. It ranges from primary snoring, its mildest clinical manifestation, to obstructive sleep apnea syndrome (OSAS): complete obstruction of the upper airways with cessation of airflow. The aim of this paper is to highlight the roles of the pediatric dentist and the orthodontist in the therapeutic approach to pediatric OSAS as a "sentinel" who can detect early signs of the disease for immediate referral to the otolaryngologist and as an active participant in therapy. MATERIALS AND METHODS: A literature review has been performed on the following topics: pediatric OSAS, orthodontic clinical aspects of pediatric OSAS, orthodontic therapy of pediatric OSAS, mandibular advancement devices and functional orthodontic devices in OSAS treatment. RESULTS: The role of the dentist in pediatric OSAS is essential to correct orthodontic alterations that may favor the development of the condition. Orthodontic treatment aims at reducing the severity of OSAS by increasing the airspace and improving airflow through orthopedic expansion of the upper jaw and mandibular advancement. Rapid palatal expanders and mandibular advancement devices are successfully used in the treatment of OSAS. CONCLUSIONS: Scientific evidence of a strong association between craniofacial growth and OSAS; the pediatric dentist and the orthodontist participate as sentinels, observing and identifying conditions requiring referral to the otolaryngologist and playing a pivotal role in the orthodontic treatment phase.

gamma-ray spectrometry of soil samples from the Provincia dell'Aquila (Central Italy).

In the Abruzzo Region (Central Italy) there is a lack of measurements of gamma-ray activity in soils and waters. For this reason, we have planned to carry out a systematic measurement of soils in the area of the Provincia dell'Aquila, which covers about one-half of the entire region. In this paper we report the results obtained from 56 soil samples, collected in the northern part of the area of interest (about one-fourth of the total area under study). The results, in terms of content of uranium, thorium and potassium and the activity of caesium are reported, as well as the details on the experimental procedure. The results show a limited content of K and U, with no large variations from site to site, in agreement with the expectations based on the knowledge of the geo-lithological nature of the soil. The amount of Th is also quite limited, with a few exceptions where the Th content is up to five times the average value. Caesium, originated from the fall-out following the Chernobyl accident, is very irregularly distributed owing to the complicated orography of the land. Future plans are also shortly discussed.

A nonlinear optical active polymer film based on Pd(ii) dithione/dithiolate second-order NLO chromophores.

A film of [Pd(R2pipdt)(dmit)] (1), where R2pipdt = 1,4-didodecyl-piperazine-2,3-dithione (acceptor) and dmit = 2-thioxo-1,3-dithiole-4,5-dithiolate (donor) incorporated into a polymethylmethacrylate (PMMA) matrix, showing a good second-harmonic generation, has been prepared for the first time in the class of dithione-dithiolate 2nd order NLO-chromophores. Moreover full characterization of 1, including molecular second-order NLO properties in solution, is reported.

4D-π-1A type ß-substituted ZnII-porphyrins: ideal green sensitizers for building-integrated photovoltaics.

Two novel green ß-substituted ZnII-porphyrins, G1 and G2, based on a 4D-π-1A type substitution pattern have been synthesized. Their enhanced push-pull character, by reduction of H-L energy gaps, promotes broadening and red-shifting of absorption bands. The effective synthetic pathway and the remarkable spectroscopic properties make G2 ideal for BIPV application.

Craniofacial morphology and airflow in children with primary snoring.

OBJECTIVE: Sleep-disordered breathing (SDB) is among the most common diseases and includes a group of pathological conditions that form a severity continuum from primary snoring (PS) to obstructive sleep apnea (OSA). SDB presents a multifactorial etiology and in children, it is often linked to adenotonsillar hypertrophy, which may lead to an alteration of the breathing pattern. Therefore, several studies hinted at the existence of a correlation between SDB and the alteration of craniofacial growth. However, these studies concentrated on the most severe forms of SDB and little evidence still exists for the mildest form of SDB, namely PS. This preliminary study investigates the association between nasal airflow, measured through rhinomanometry, and cephalometric parameters in a sample of young children with PS. PATIENTS AND METHODS: A sample of 30 children with habitual snoring aged between 5 and 8 years was selected by a SDB validated questionnaire at the Pediatric Allergology and Immunology Center of "Sapienza" University of Rome, Italy. To assess the degree of nasal obstruction, all children underwent anterior active rhinomanometry while nocturnal pulse oximetry and polysomnography were used to characterize the SDB. Cephalometric analysis was used to evaluate relevant orthodontic parameters associated to the sagittal and vertical craniofacial development and to the position of the hyoid bone. RESULTS: We found a statistically significant association between the Frankfurt mandibular angle (FMA), which measures the total facial vertical divergence, and the severity of the airflow's obstruction (p = 0.014). CONCLUSIONS: The present study supports the association between the level of nasal obstruction in children with PS and the alteration of cephalometric parameters associated with the vertical craniofacial growth, thus placing the evaluation of craniofacial parameters in the growth period in a privileged position to determine an early diagnosis of a possible insurgence of sleep disorders.

St John's wort: Prozac from the plant kingdom.

Conventional antidepressants are associated with a range of adverse drug reactions. The herb Hypericum perforatum (St John's wort) might offer another approach to the treatment of depression. Biochemical and animal studies suggest that the phloroglucinol derivative hyperforin is the main active ingredient of St John's wort, and inhibits the synaptosomal uptake of 5-HT, noradrenaline, dopamine, glutamate and GABA. St John's wort has been shown to alleviate symptoms of mild to moderate depression, and seems to offer significant advantages over conventional antidepressants because it is associated with fewer adverse reactions. However, important herb--drug interactions have been described. In view of its efficacy and safety records, St John's wort should be considered for the first-line treatment of mild to moderate depression.

Gender assessment through three-dimensional analysis of maxillary sinuses by means of cone beam computed tomography.

OBJECTIVE: The availability of a low dose radiation technology such as Cone Beam Computed Tomography (CBCT) in dental practice has increased the number of scans available for forensic purposes. Moreover, specific software allows for three-dimensional (3D) characterization of the maxillary sinuses. This study was performed to determine whether sinus maxillary volumes can be useful to identify gender after validating the use of the Dolphin software as a tool for volumetric estimation of maxillary sinus volumes. PATIENTS AND METHODS: The validation was performed by four different operators measuring the volume of six phantoms, where the real volume was already known. The maxillary sinus volumes of 52 patients (26 males and 26 females) mean age 24.3 were calculated and compared between genders and sagittal skeletal class subdivision. The measurements for patients and phantoms were based on CBCT scans (ILUMA™) processed by Dolphin 3D software. RESULTS: No statistical difference was observed between the real volume and the volume measurements performed by the operators. No statistical difference was found in patient's maxillary sinus volumes between gender. CONCLUSIONS: Based on our results, it is not possible to support the use of maxillary sinuses to discern sexual difference in corpse identification.

Ascending neural pathways in the isolated guinea-pig ileum: effect of muscarinic M1, M2 and M3 cholinergic antagonists.

The effect of muscarinic cholinoceptor antagonists was investigated on the ascending neural pathways activated by electrical stimulation in the guinea-pig ileum. For comparison, prejunctional and postjunctional effects of muscarinic cholinoceptor antagonists were also studied on circular smooth muscle. A two-compartment (oral and anal compartments) bath was used to study the ascending neural pathways. These were activated by electrical field stimulation in the anal compartment and the resulting contraction of the intestinal circular muscle in the oral compartment was recorded isotonically. Pirenzepine (10-300 nM), a muscarinic M1 cholinoceptor antagonist, reduced the ascending neural contractions in a concentration-dependent fashion when applied either to the oral or anal compartments (11-52% and 13-55% inhibition, respectively, P < 0.05). Pirenzepine inhibited (31+/-7%, P < 0.05) the acetylcholine (100 nM)-induced contractions at a higher non-selective concentration (300 nM), while its effect on the electrically-induced contractions was biphasic (10 and 30nM: 8-15% increase, P<0.05; 100 and 300 nM: 16-28% inhibition, P<0.05). The muscarinic M2 cholinoceptor antagonist methoctramine (3-100 nM) did not modify the contractions produced by 100 nM acetylcholine, electrically-induced contractions and the ascending neural contractions (when applied to either compartment). Parafluorohexahydrosiladifenidol (3-100 nM), a muscarinic M3 cholinoceptor antagonist, inhibited the contractions produced by 100 nM acetylcholine (19-81% and 15-69%), electrically-induced contractions (11-71% and 12-72%) and the ascending neural contractions (13-76% and 866%) when applied to the oral compartment, but it was without effect when applied to the anal compartment. These studies suggest that in the enteric ascending neural pathway, muscarinic M1 receptors are involved in neuroneuronal transmission, muscle contraction is mediated by muscarinic M3 cholinergic receptors, whereas muscarinic M2 receptors do not seem to participate.

Effect of cholera toxin on the production of eicosanoids by rat jejunum.

1 Cholera toxin injected i.v. into rats stimulated the production of prostaglandin E2 (PGE2), leukotriene B4 (LTB4) and LTC4 by segments of jejunum, but it had no effect when added to the tissue in vitro. 2 Pretreatment of the animals with the compound BW 755C reduced the increased production of PGE2, LTB4 and LTC4 by i.v. cholera toxin. Pretreatment with indomethacin reduced the production of PGE2. 3 These findings are consistent with the hypothesis that arachidonate metabolites are involved in the diarrhoea induced by cholera toxin.

Effect of vanilloid drugs on gastrointestinal transit in mice.

1. We have studied the effect of capsaicin, piperine and anandamide, drugs which activate vanilloid receptors and capsazepine, a vanilloid receptor antagonist, on upper gastrointestinal motility in mice. 2. Piperine (0.5 - 20 mg kg(-1) i.p.) and anandamide (0.5 - 20 mg kg(-1) i.p.), dose-dependently delayed gastrointestinal motility, while capsaicin (up to 3 mg kg(-1) i.p.) was without effect. Capsazepine (15 mg kg(-1) i.p.) neither per se affected gastrointestinal motility nor did it counteract the inhibitory effect of both piperine (10 mg kg(-1)) and anandamide (10 mg kg(-1)). 3. A per se non effective dose of SR141716A (0.3 mg kg(-1) i.p.), a cannabinoid CB(1) receptor antagonist, counteracted the inhibitory effect of anandamide (10 mg kg(-1)) but not of piperine (10 mg kg(-1)). By contrast, the inhibitory effect of piperine (10 mg kg(-1)) but not of anandamide (10 mg kg(-1)) was strongly attenuated in capsaicin (75 mg kg(-1) in total, s.c.)-treated mice. 4. Pretreatment of mice with N(G)-nitro-L-arginine methyl ester (25 mg kg(-1) i.p.), yohimbine (1 mg kg(-1), i.p.), naloxone (2 mg kg(-1) i.p.), or hexamethonium (1 mg kg(-1) i.p.) did not modify the inhibitory effect of both piperine (10 mg kg(-1)) and anandamide (10 mg kg(-1)). 5. The present study indicates that the vanilloid ligands anandamide and piperine, but not capsaicin, can reduce upper gastrointestinal motility. The effect of piperine involves capsaicin-sensitive neurones, but not vanilloid receptors, while the effect of anandamide involves cannabinoid CB(1), but not vanilloid receptors.

Endocannabinoids and the gut.

In the digestive tract, there is evidence for the presence of high amounts of endocannabinoids (anandamide and 2-arachidonylglycerol) and of mechanisms for endocannabinoid metabolism and possibly endocannabinoid uptake. Pharmacological studies have shown that anandamide inhibits excitatory transmission and peristalsis in the isolated guinea-pig ileum and reduces intestinal motility in the mouse in vivo; all these effects are mediated by CB(1) receptors, which are located on enteric nerves. Conversely, the selective CB(1) receptor antagonist SR141716A increased intestinal motility and this effect is likely due to the displacement of endocannabinoids rather than to its inverse agonist properties. Interestingly, inhibitory effects of anandamide via non-CB(1) receptors and stimulatory effects via vanilloid receptors have also been proposed.

Histamine H(3)-receptor antagonism improves memory retention and reverses the cognitive deficit induced by scopolamine in a two-trial place recognition task.

Several reports have indicated that, under different experimental conditions, the administration of histamine H(3)-receptor antagonists exerts procognitive effects by activating central histaminergic transmission. In the present study the action of thioperamide, a H(3)-receptor blocker, is investigated on consolidation and recall mechanisms of the rat place recognition memory. The animals have been tested on a two-trial delayed comparison paradigm in a Y-maze. Thioperamide enhances the memory retention when administered intraperitoneally (i.p.) post-acquisition (0.7 and 5.0 mg/kg are ineffective, whereas the dose of 2.0 mg/kg improves memory) but does not affect the rat performance when injected 45 min prior to the testing trial. The post-acquisition effect of thioperamide is time-dependent since the administration of the drug 30 min after the end of the training trial has no effect on memory. In addition, thioperamide reverses the amnesia induced by the post-acquisition treatment with 0.02 mg/kg i.p. of scopolamine (SCOP). The procognitive effect of thioperamide is not modified by the contemporary administration of pyrilamine, an histamine H(1)-receptor antagonist. On the contrary, the blockade of H(2)-receptors by zolantidine 10 mg/kg reverses both the effect of thioperamide alone and the drug action on the scopolamine-induced memory deficit. The results indicate that the neuronal histamine released in consequence of the post-acquisition thioperamide treatment improves place recognition memory through the activation of postsynaptic H(2)-receptors.

NG-nitro-L-arginine methyl ester modulates intestinal secretion and motility produced by carbachol.

The effects of the nitric oxide (NO) synthesis inhibitor, NG-nitro-L-arginine methyl ester, on carbachol-induced diarrhoea, fluid accumulation and motility changes were studied. Pretreatment of mice with NG-nitro-L-arginine methyl ester (1-25 mg/kg i.p.) and NG-nitro-L-arginine (2.5-50 mg/kg i.p.) but not NG-nitro-D-arginine methyl ester (25 mg/kg i.p.) prevented in a dose-related manner the carbachol (0.5 mg/kg i.p.)-induced diarrhoea in mice. L-Arginine (150-1500 mg/kg i.p.) administered to mice pretreated with NG-nitro-L-arginine methyl ester counteracted the antidiarrhoeal activity of NG-nitro-L-arginine methyl ester in a dose-related manner. Pretreatment of rats with NG-nitro-L-arginine methyl ester (2.5-25 mg/kg i.p.) decreased the intestinal fluid accumulation induced by carbachol in rats. NG-Nitro-D-arginine methyl ester was without effect. Intraperitoneal pretreatment of rats with NG-nitro-L-arginine methyl ester (2.5-25 mg/kg) reduced the increase in small intestinal transit induced by carbachol. NG-nitro-L-arginine methyl ester had no effect. These results provide evidence that nitric oxide may play a role in diarrhoea, intraluminal fluid accumulation and motility changes induced by carbachol.

Nitric oxide involvement in sodium choleate-induced fluid secretion and diarrhoea in rats.

Bile salt-induced diarrhoea, net water and electrolyte secretion, gastrointestinal transit and nitric oxide (NO) synthase activity were studied in rats. NG-Nitro-L-arginine methyl ester (2.5-25 mg/kg i.p.), an inhibitor of NO synthase, and dexamethasone (0.03-0.3 mg/kg i.p.), an inhibitor of the inducible isoform of NO synthase, antagonized the diarrhoeal response. The NO precursor, L-arginine and isosorbide-5-mononitrate (an NO donor), reversed the inhibitory effect of NG-nitro-L-arginine methyl ester. The bile salt-stimulated fluid secretion, transit through the gut and NO synthase all were inhibited by NG-nitro-L-arginine methyl ester (but not NG-nitro-D-arginine methyl ester). NO synthase activity also was inhibited by dexamethasone. The results are consistent with bile salt induction of epithelial cell injury and concomitant synthesis of NO, mainly through activation of the inducible form of the enzyme. We believe that in this study NO is a mediator of intestinal secretion and motility changes that enhance transit of luminal contents through the gut, resulting in diarrhoea.