Twins with hereditary sensory and autonomic neuropathy type IV with preserved periodontal sensation

Turkish twin brothers affected with hereditary sensory and autonomic neuropathy type IV (HSAN IV) are reported. Their clinical findings were generally typical for HSAN IV. Interestingly they both had preserved periodontal sensation. Mutation analysis of the NTRK1 gene showed a homozygous c.2001C>T substitution in exon 15 in both twins. This base substitution is predicted to change a polar, positively charged amino acid arginine to the highly active amino acid cystein at position 654 (p.Arg654Cys). The parents were heterozygous for the mutation. This mutation has been reported previously in one Japanese and one Arab patients. The preserved periodontal sensation has not previously been reported in patients affected with HSAN IV. This preserved sensation in our patients might have been through Ruffini endings, the periodontal mechanoreceptors which have been reported to be present in TrkA knockout mice. Here we report the first twins affected with HSAN IV and the observation that periodontal sensation is not affected by mutation in NTRK1.     

Color change of primary teeth following exposure to an experimentally synthesized liposomal nano-encapsulated ferrous sulfate drop versus the commercially available iron drops

ObjectivesThis study aimed to assess the color change of primary teeth following exposure to an experimentally synthesized liposomal nano-encapsulated ferrous sulfate drop compared with the commercially iron drops.Materials and methodsIn this in-vitro study, liposomal nano-encapsulated ferrous sulfate (lipo-nano-ferr) drop was first synthesized. Next, 110 extracted primary anterior teeth were randomized into two equal groups (sound and demineralized). Each group was randomly divided into 5 subgroups (n = 11) and exposed to Irofant, Feroglobin, Sideral, and lipo-nano-ferr drops for 540 cycles. One subgroup was remained in artificial saliva as the negative control. Tooth color was analyzed before and after the interventions visually, and the rate of iron adsorption was analyzed by atomic absorption spectrometry (AAS), and energy-dispersive X-ray spectroscopy/scanning electron microcopy (EDS/SEM). Data were analyzed using t-test, one-way ANOVA, and LSD test.ResultsIron adsorption was significantly higher by the demineralized specimens than the sound specimens in all subgroups (P < 0.001). A significant difference was noted in iron adsorption among the four subgroups in each of the sound and demineralized groups (P < 0.001). Iron adsorption in the lipo-nano-ferr subgroup was significantly lower than that in Irofant and Feroglobin groups (P < 0.001). The visual inspection results were similar to AAS results. EDS-SEM showed that the atomic percentage of iron in Sideral and lipo-nano-ferr groups was significantly lower than that in Irofant and Feroglobin groups (P < 0.001).ConclusionUse of nano-encapsulation technology in production of iron drops can significantly decrease the resultant tooth discoloration, causing a clinically negligible color change.     

Risk of bleeding after dentoalveolar surgery in patients taking anticoagulants

To avoid increasing the risk of thromboembolic events, it is recommended that treatment with anticoagulants should be continued during dentoalveolar operations. We have evaluated the incidence of bleeding after dentoalveolar operations in a prospective study of 206 patients, 103 who were, and 103 who were not, taking anticoagulants. Seventy-one were taking thrombocyte aggregation inhibitors and 32 vitamin K antagonists. Patients were treated according to guidelines developed at the Academic Centre for Dentistry Amsterdam (ACTA), The Netherlands. The operations studied included surgical extraction (when the surgeon had to incise the gingiva before extraction), non-surgical extraction, apicectomy, and placement of implants. Patients were given standard postoperative care and those taking vitamin K antagonists used tranexamic acid mouthwash postoperatively.     

佛山市敬老院老人牙缺失及义齿修复情况的调查分析

目的通过对佛山市敬老院老人义齿使用情况的调查,为指导敬老院老人做好缺失牙修复工作、促进口腔健康、促进全身健康、提高生命质量提供理论依据。方法自2015年7月~2016年12月期间,对佛山市辖区内6间敬老院共517例老年人采用问卷调查和口腔检查方式,了解其牙缺失及义齿修复状况。结果敬老院老人口腔卫生情况欠佳;517例受访对象共缺失牙齿7611颗,人均缺牙14.72颗,未修复缺牙占32.77%,前牙缺失率为50.53%,后牙缺失率为54.11%,前后牙缺失率无显著性差异(P0.05);前牙修复率为89.00%,后牙修复率为51.99%,前后牙修复率有显著性差异,后牙修复率明显比前牙低(P0.01)。义齿修复主要以可摘局部义齿为主,占52.95%;不良修复体占23.32%,未发现种植义齿和精密附着体义齿类型。结论敬老院老人缺牙率高,修复率低,修复质量不高。应关注敬老院老人这一特殊群体的缺牙问题,采取相关措施提高修复率,提高老年人生活质量,提升幸福感,促进社会和谐。     

Ionic liquid as antibacterial agent for an experimental orthodontic adhesive

ObjectiveThe aim of this study was to formulate and evaluate experimental orthodontic adhesives with different concentrations of 1-n-butyl-3-methylimidazoilium bis(trifluoromethanesulfonyl)imide (BMIM.NTf₂).MethodsThe experimental orthodontic adhesives were formulated with methacrylate monomers, photoinitiators and silica colloidal. The ionic liquid BMIM.NTf₂ was synthesized and characterized. BMIM.NTf₂ was added at 5 (G_5%), 10 (G_10%) and 15 (G_15%) wt.%. One group contained no BMIM.NTf₂ to function as control (G_Ctrl). The adhesives were evaluated for polymerization kinetics, degree of conversion (DC), Knoop hardness and softening in solvent, ultimate tensile strength (UTS), shear bond strength (SBS), thermogravimetric analysis (TGA), antibacterial activity and cytotoxicity.ResultsBMI.NTf₂ showed the characteristic chemical peaks. The polymerization kinetics were different among the groups. G_10% and G_15% showed higher DC (p < 0.05). G_5% and G_Ctrl had no differences for softening in solvent (p > 0.05). There were no differences for UTS (p > 0.05) and SBS (p > 0.05). TGA showed one different peak for G_15%. All groups with BMIM.NTf₂ showed antibacterial activity compared to G_Ctrl (p < 0.05) without cytotoxicity (p > 0.05).SignificanceTo reduce biofilm formation around brackets and to prevent demineralization at susceptible sites, materials have been developed with antibacterial properties. In this study, a new experimental orthodontic adhesive was formulated with an imidazolium ionic liquid (BMIM.NTf₂) as antibacterial agent. The incorporation of 5 wt.% of ionic liquid decreased biofilm formation without affecting the physico-chemical properties and cytotoxicity of an experimental orthodontic resin.