Proprioceptive mechanisms in occlusion-stimulated masseter hypercontraction

Neurons in the trigeminal mesencephalic nucleus (Vme) have an axon that branches peripherally to innervate the orofacial region and projects centrally to the trigeminal motor nucleus (Vmo). They function as the primary neurons conveying proprioceptive messages. The present study aimed to demonstrate the presence of a periodontal–Vme–Vmo circuit and to provide evidence for its involvement in an experimental unilateral anterior crossbite (UAC) model, which can induce osteoarthritis in the temporomandibular joint. Cholera toxin B subunit (CTb) was injected into the inferior alveolar nerve of rats to help identify the central axon terminals of Vme neurons in the Vmo. The levels of vesicular glutamate transporter 1 (VGLUT1) expressed in the periodontal region, Vme, Vmo, and masseter, and the level of acetylcholinesterase (AChE) expressed in the masseter, were assessed in UAC rats and controls. In CTb-treated rats, many CTb-labeled cell bodies and endings were identified in the Vme and in the Vmo, respectively. In UAC rats, VGLUT1 was expressed at a statistically significantly higher level in the periodontal ligament, Vme, Vmo, and masseter than it was in control rats. The level of AChE protein was 1.97 times higher in UAC rat masseter compared with control rat masseter. These findings reveal a trigeminal mechanism underlying masseter hyperactivity induced by an altered occlusion.

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Wear characteristics and inhibition of enamel demineralization by resin-based coating materials

In this study, wear and inhibition of enamel demineralization by resin-based coating materials were investigated. Seven commercially available coating materials, with and without fillers, were used. A mechanical wear test was performed, and the specimens were then examined with a scanning electron microscope. Hardness and elastic modulus measurements for each material were obtained by nanoindentation testing. Thin layers of each material were applied on human enamel surfaces, which were subjected to alternating immersion in demineralizing and remineralizing solutions. The inhibition ability of enamel demineralization adjacent to the coating was estimated with depth-dependent mechanical properties using the nanoindentation test. The non-filled coating material showed significantly lower hardness, lower elastic modulus, and higher weight loss. There were no significant differences in weight loss among the six filled coating materials. After the alternating immersion protocol, the enamel specimens having application of coating materials with ion-releasing ability were harder than those in the other groups in some locations 1–11 μm from the enamel surface and within 300 μm from the edge of the coating materials. In conclusion, clinical use of the resin-based coating materials with ion-releasing ability may prevent demineralization of exposed enamel adjacent to the coating during treatment.

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Inferior alveolar neurovascular bundle repositioning: a retrospective analysis

Publication date: Available online 31 January 2017
Source:International Journal of Oral and Maxillofacial Surgery
Author(s): A. Sethi, S. Banerji, T. Kaus
In this study, patients with an insufficient height of bone for implant placement in the posterior mandible were treated by repositioning of the inferior alveolar neurovascular bundle (IANVB). These patients were divided into two groups: those in group A (n=69) did not require a bone graft and implants were placed at the time of nerve repositioning; those in group B (n=9) received bone grafts in conjunction with nerve repositioning and implants were placed upon maturation of the grafts. One hundred and twenty-one nerves were repositioned in 78 patients and 308 implants were placed. Three implants failed within the first 10 months after placement. With a certainty of 95%, an estimated overall mean survival rate better than 97.8% was observed after a mean observation period of 84.5 months. The recovery of sensation was monitored using standardized tests. The recovery of sensation varied from 24h to 6 months. Five patients reported some residual altered sensation. The technique of repositioning the IANVB provides an effective way of treating the atrophic posterior mandible with acceptable morbidity and a high implant survival rate; however the risk of dysesthesia must be acknowledged and patients properly informed.



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Baked milk tolerant patient: Is there any special feature?

Publication date: Available online 1 February 2017
Source:Allergologia et Immunopathologia
Author(s): C.P.G. Barbosa, A.P.M. Castro, G.H. Yonamine, A.K.F. Gushken, C.M.L. Beck, P.R.C. Macedo, M.B. Dorna, C.J.N. Santos, A.C. Pastorino, C.M.A. Jacob
BackgroundDetermining whether patients with cow's milk allergy (CMA) can tolerate foods produced with baked milk could provide a better quality of life, a better prognosis, and an option for desensitization.ObjectivesThe aim of this study was to identify which patients over four years of age with persistent CMA could tolerate baked milk, to compare the clinical and laboratory characteristics of reactive and non-reactive groups and to describe their clinical evolution.Materials and methodsA cross-sectional study was conducted (January/13 to November/14) that included all the patients followed at a food allergy center who met the inclusion criteria. The patients underwent an oral food challenge (OFC) with a muffin (2.8g of cow's milk protein). To exclude cow's milk (CM) tolerance, the patients were subsequently challenged with unheated CM.ResultsThirty patients met all the inclusion criteria. Fourteen patients (46.7%) were considered non-reactive to baked milk and reactive to unheated CM. When the groups that were reactive and non-reactive to baked milk were compared, no statistically significant differences in clinical features were found. The prick test for α-lactalbumin (p=0.01) and casein (p=0.004) and the serum specific IgE for casein (p=0.05) presented statistical differences. After one year, none of the patients who were reactive to baked milk were ingesting CM, while 28% of the tolerant patients were consuming fresh CM (p=0.037).ConclusionsBaked milk can be tolerated by patients with CMA, especially those with lower levels of casein and α-lactalbumin. This option can improve quality of life and accelerate tolerance.



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Tolerance development in food protein-induced allergic proctocolitis: Single centre experience

Publication date: Available online 1 February 2017
Source:Allergologia et Immunopathologia
Author(s): S.B. Erdem, H.T. Nacaroglu, S. Karaman, C.B. Erdur, C.U. Karkıner, D. Can
BackgroundFood protein-induced allergic proctocolitis (FPIAP) is characterised by inflammation of the distal colon in response to one or more food proteins. It is a benign condition of bloody stools in a well-appearing infant, with usual onset between one and four weeks of age.ObjectiveOur objective was to examine the clinical properties of patients with FPIAP, tolerance development time as well as the risk factors that affect tolerance development.MethodsThe clinical symptoms, offending factors, laboratory findings, methods used in the diagnosis and tolerance development for 77 patients followed in the Paediatric Allergy and Gastroenterology Clinics with the diagnosis of FPIAP during January 2010–January 2015 were examined in our retrospective cross-sectional study.ResultsThe starting age of the symptoms was 3.3±4.7 months (0–36). Milk was found as the offending substance for 78% of the patients, milk and egg for 13% and egg for 5%. Mean tolerance development time of the patients was 14.7±11.9 months (3–66 months). Tolerance developed before the age of one year in 40% of the patients. Tolerance developed between the age of 1–2 years in 27%, between the age of 2–3 years in 9% and after the age of 3 years in 5% of the patients.ConclusionsSmaller onset age and onset of symptoms during breastfeeding were found associated with early tolerance development. In the majority of the patients, FPIAP resolves before the age of one year, however in some of the patients this duration may be much longer.



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Single nucleotide polymorphisms of IL-2, but not IL-12 and IFN-γ, are associated with increased susceptibility to chronic spontaneous urticaria

Publication date: Available online 1 February 2017
Source:Allergologia et Immunopathologia
Author(s): M. Movahedi, M. Tavakol, F. Rahmani, A.A. Amirzargar, A.Z. Bidoki, K. Heidari, M. Gharagozlou, A. Aghamohammadi, M. Nabavi, S. Soltani, N. Rezaei
BackgroundA clear picture of interaction of Th1/Th2 cytokines in pathogenesis of chronic spontaneous urticaria (CSU), remains elusive. Impaired IFN-γ production and decreased levels of IL-2 have been reported. The aim of this study was to evaluate the association of Th1 cytokines; IL-2, IL-12 and IFN-γ polymorphisms with CSU.Methods90 patients with CSU and 140 age-sex matched subjects were included in this study. DNA samples were evaluated through PCR-SSP assay in order to detect single nucleotide polymorphisms of IL-12 (A/C −1188) or (rs3212227), IFN-γ (A/T UTR5644) or (rs2069717) and IL-2 (G/T −330 and G/T +166) or (rs2069762 and rs2069763).ResultsG allele at −330 at promoter region of IL-2 gene was overrepresented in CSU. Heterozygotes (GT) at this locus and heterozygotes at +166 of IL-2 gene (GT) were more prevalent in CSU group. Additionally, the haplotype GT for loci −330 and +166 of IL-2 gene was powerfully associated with CSU (OR (95%CI)=57.29 (8.43–112.7)).ConclusionsSNP at position −330 and +166 of IL-2 gene are differently expressed in CSU. The haplotype GT of IL-2 at −330 and +166 might confer vulnerability to a number of immunological disorders in Iranian region.



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Implante coclear en paciente con schwannoma intracoclear

Publication date: Available online 1 February 2017
Source:Acta Otorrinolaringológica Española
Author(s): Carlos de Paula Vernetta, Nabil Atrache Al Attrache, Laura Cavallé Garrido, Fernando Mas Estellés, Constantino Morera Pérez




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