SummaryBackground:Using lingual enamel surfaces for bracket placement not only has esthetic advantages, but may also be suitable in terms of reducing frequencies of enamel decalcifications.Objective:To test the null-hypothesis that there is no significant difference in enamel decalcification or cavitation incidence adjacent to and beneath bracket bases between two lingual multi-bracket (MB) appliances that are different in terms of design, material composition, and manufacturing technology (group A: WIN, DW-LingualSystems; group B: Incognito, 3M-Unitek), taking into account patient- and treatment-related variables on white spot lesion (WSL) formation.Methods:Standardized, digital, top-view photographs of 630 consecutive subjects (16214 teeth; n Incognito = 237/6076 teeth; n WIN = 393/10138 teeth; mean age: 17.47±7.8; m/f 43.2/56.8%) with completed lingual MB treatment of the upper and lower permanent teeth 1–7 were screened for decalcification or cavitation adjacent to and beneath the bracket bases before and after treatment, scored from 0 to 7. Non-parametric ANOVA was used for main effects ‘appliance type’, ‘gender’, ‘treatment complexity’, ‘grouped age’ (≤16/>16 years), and ‘treatment duration’ as covariable, at an α-level of 5%.Results:About 2.57% [5.94%] of all teeth in group A [B] developed decalcifications. Subject-related incidence was 9.59% [16.17%] for upper incisors in group A [B], and 12.98% [25.74%] for all teeth 16–46. There were significant effects by gender, age, and treatment duration.Conclusion:The null-hypothesis was rejected: sub-bracket lesions were significantly less frequent in group A, while frequencies of WSL adjacent to brackets were not significantly affected by appliance type. In view of the overall low incidences of lingual post-orthodontic white-spot lesions, the use of lingual appliances is advocated as a valid strategy for a reduction of enamel decalcifications during orthodontic treatment.

No abstract

IntroductionThe occurrence of side-effects of fixed orthodontic therapy, such as white-spot lesions and root resorption, are known to be significantly more frequent with increasing duration of treatment. Multi-bracket treatment should be as short as possible, in order to minimize the risks of collateral damage to teeth. The aim of this non-randomized clinical trial was to compare treatment duration with each of two types of customized lingual orthodontic appliances (Incognito, 3 M-Unitek; WIN, DW LingualSystems), taking into account treatment complexity. The null-hypothesis was that there would be no significant difference in active orthodontic treatment duration between them.MethodsOf 402 potentially eligible participants, a population sample of n = 376 subjects (nIncognito = 220; nWIN = 156; m/f 172/204; mean age ± SD 17.3 ± 7.7Y) treated in one orthodontic center (Bad Essen, Germany) with completely customized lingual appliances in upper and lower permanent dental arches was recruited with the inclusion criterion of initiated and completed lingual multi-bracket treatment within the assessment period of April 1st 2010 – Nov 30, 2013, and the exclusion criterion of less than 24 bracketed teeth. We used four-factorial ANOVA to assess the impact of the following factors: initial degree of severity of malocclusion (mild to moderate, S1; severe, S2), appliance type (Incognito; WIN), sex, and age group (<=16; >16 Y) on the duration of lingual multi-bracket treatment.ResultsOverall, mean treatment duration was 21.7 (SD 7.2) months, which was significantly shorter for WIN for both sub-groups of treatment complexity (S1: 17.96 mo; S2: 20.49 mo) compared to Incognito (S1: 22.7 mo; S2: 29.79 mo). ANOVA revealed a significant influence of the main effects ‘appliance type’, and ‘severity’, independent of each other. Therefore, the null-hypothesis was rejected.ConclusionIn terms of treatment duration, the WIN appliance performed significantly better than the Incognito appliance. Consequently, subjects treated with the WIN appliance are expected to be exposed to lower risks of the typical side-effects associated with longer multi-bracket treatment durations, such as root resorption and enamel decalcification.

The glucose-phosphotransferase system (PTS) in Escherichia coli K-12 is a complex sensory and regulatory system. In addition to its central role in glucose uptake, it informs other global regulatory networks about carbohydrate availability and the physiological status of the cell. The expression of the ptsG gene encoding the glucose-PTS transporter EIICB Glc is primarily regulated via the repressor Mlc, whose inactivation is glucose dependent. During transport of glucose and dephosphorylation of EIICB Glc , Mlc binds to the B domain of the transporter, resulting in derepression of several Mlc-regulated genes. In addition, Mlc can also be inactivated by the cytoplasmic protein MtfA in a direct protein-protein interaction. In this study, we identified the binding site for Mlc in the carboxy-terminal region of MtfA by measuring the effect of mutated MtfAs on ptsG expression. In addition, we demonstrated the ability of MtfA to inactivate an Mlc super-repressor, which cannot be inactivated by EIICB Glc , by using in vivo titration and gel shift assays. Finally, we characterized the proteolytic activity of purified MtfA by monitoring cleavage of amino 4-nitroanilide substrates and show Mlc's ability to enhance this activity. Based on our findings, we propose a model of MtfA as a glucose-regulated peptidase activated by cytoplasmic Mlc. Its activity may be necessary during the growth of cultures as they enter the stationary phase. This proteolytic activity of MtfA modulated by Mlc constitutes a newly identified PTS output signal that responds to changes in environmental conditions. D espite the fact that Escherichia coli K-12 has been an important model organism for many decades, the function of Ͼ20% of all putative open reading frames in its genome remains unknown. Moreover, in many cases, no obvious sequence similarities with previously characterized proteins exist. The mtfA gene (formerly named yeeI), a monocistronic gene located at 44.1 min in the E. coli chromosome, has clearly belonged to this group. Intensive sequence similarity searches revealed that orthologs of MtfA (mnemonic for Mlc titration factor A) exist in more than 100 proteobacteria of the alpha, beta, and gamma subdivisions. In a previous report (2), we were able to demonstrate that E. coli MtfA is a cytoplasmic protein that binds to the carboxy-terminal part of the Mlc repressor protein (mnemonic for "making large colonies" [gene, dgsA]) with a very high affinity. Mlc is one of the global regulators of carbohydrate metabolism in E. coli and is especially involved in the regulation of the ptsG gene expression, which encodes the glucose transporter EIICB Glc . The EIICB Glc together with the cytoplasmic protein EIIA Glc , encoded by the crr gene (as part of the ptsHI-crr operon), forms the glucosespecific phosphoenolpyruvate (PEP)-dependent carbohydratephosphotransferase system (glucose-PTS). Both proteins take part in a phosphorylation cascade, which begins with an autophosphorylation reaction of the so-called enzyme I (EI; gene, ptsI) at the expense...

BackgroundControlled space closure in cases of isolated lower second premolar aplasia (ILSPA) without maxillary counterbalancing extraction is challenging. Anterior anchorage loss may occur during space closure resulting in compromised occlusal results in terms of an absence of proper canine guidance during laterotrusive mandible movements.In order to evaluate the effectiveness of Herbst telescope anchorage in combination with double-cable, pull mechanics and a completely customized lingual appliance for orthodontic space management in cases of ILSPA, we tested the null hypothesis that there is a significant deterioration in the sagittal canine relationship towards an Angle-Class-II occlusion expressed as a loss of anterior anchorage following space closure with molar mesialization.MethodsTwenty-five consecutively de-bonded subjects (female / male 17 / 8; aged at T0 (start of MB Tx) 12.3 to 20.6 years; mean age 15.0 / SD 1.7 years) were included in this retrospective analysis using the inclusion criteria of least of one lower second premolar aplasia; completed treatment with a totally customized lingual appliance (CCLA) in combination with Herbst telescopes. Exclusion criteria were the absence of counterbalancing maxillary extractions, as well as additional tooth aplasia other than lower second premolars. A total of 33 single, lower premolar aplasia space closures (right / left sided 17 / 16) were assessed using plaster casts and intra-oral photographs scaled to the plaster casts, at bonding (T0), Herbst insertion (T1), following gap closure (T2) and de-bonding (T3). Parallelism of roots was controlled by panoramic x-rays at T3.ResultsThe mean aplasia space at T0 was 7.5 mm (SD 2.6). Complete space closure was achieved in all 33 situations. The null hypothesis was rejected. There was a significant improvement in the initial canine relationships (mean 3.5 mm distal occlusion at T0) to a mean 0.1 mm at T3. When evaluated against the individual treatment plan, the following amounts of planned improvements were achieved: space closure 100%, canine relationship 97.5%, overjet 93.9%, overbite 96.4%, parallel roots in space closure site 93.9%.ConclusionHerbst telescope anchorage in combination with double-cable pull mechanics and a CCLA for orthodontic space closure can deliver predictable, high-quality treatment results.