To gain more insight into protein structure-function relationships that govern ectopic biomineralization processes in kidney stone formation, we have studied the ability of urinary proteins (Tamm-Horsfall protein, osteopontin (OPN), prothrombin fragment 1 (PTF1), bikunin, lysozyme, albumin, fetuin-A), and model compounds (a bikunin fragment, recombinant-, milk-, bone osteopontin, poly-L-aspartic acid (poly asp), poly-L-glutamic acid (poly glu)) in modulating precipitation reactions of kidney stone-related calcium oxalate mono- and dihydrates (COM, COD). Combining scanning confocal microscopy and fluorescence imaging, we determined the crystal faces of COM with which these polypeptides interact; using scanning electron microscopy, we characterized their effects on crystal habits and precipitated volumes. Our findings demonstrate that polypeptide adsorption to COM crystals is dictated first by the polypeptide's affinity for the crystal followed by its preference for a crystal face: basic and relatively hydrophobic macromolecules show no adsorption, while acidic and more hydrophilic polypeptides adsorb either nonspecifically to all faces of COM or preferentially to {100}/{121} edges and {100} faces. However, investigating calcium oxalates grown in the presence of these polypeptides showed that some acidic proteins that adsorb to crystals do not affect crystallization, even if present in excess of physiological concentrations. These proteins (albumin, bikunin, PTF1, recombinant OPN) have estimated total hydrophilicities from 200 to 850 kJ/mol and net negative charges from -9 to -35, perhaps representing a "window" in which proteins adsorb and coat urinary crystals (support of excretion) without affecting crystallization. Strongest effects on crystallization were observed for polypeptides that are either highly hydrophilic (>950 kJ/mol) and highly carboxylated (poly asp, poly glu), or else highly hydrophilic and highly phosphorylated (native OPN isoforms), suggesting that highly hydrophilic proteins strongly affect precipitation processes in the urinary tract. Therefore, the level of hydrophilicity and net charge is a critical factor in the ability of polypeptides to affect crystallization and to regulate biomineralization processes.

This study aims to critically evaluate orthodontically induced external apical root resorption (OIEARR) in incisors of patients undergoing non-surgical orthodontic treatment of class II division 1 malocclusion by a systematic review of the published data. An electronic search of two databases was performed; the bibliographies of relevant articles were also reviewed. Studies were included if they examined the amount of OIEARR in incisors produced during non-surgical orthodontic treatment of individuals with class II division I malocclusion in the permanent dentition. Individuals had no previous history of OIEARR, syndromes, pathologies, or general diseases. Study selections, risk of bias assessment, and data extraction were performed in duplicate. Eight studies of moderate methodological quality were finally included. An increased prevalence (65.6% to 98.1%) and mild to moderate severity of OIEARR (<4 mm and <1/3 original root) were reported. No sex difference in root resorption was found. For the maxillary incisors, there was no evidence that either the central or lateral incisor was more susceptible to OIEARR. A weak to moderate positive correlation between treatment duration and root resorption, and anteroposterior apical displacement and root resorption was found. Current limited evidence suggests that non-surgical comprehensive orthodontic treatment to correct class II division 1 malocclusions causes increased prevalence and severity of OIEARR the more the incisor roots are displaced and the longer this movement takes.

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SUMMARY Objective: to critically analyse the available scientific literature radiographically comparing the incidence of orthodontically induced external apical root resorption (OIEARR) in human root-filled and vital teeth. Methods: Several electronic databases (MEDLINE, PubMed, EMBASE, Scopus, Web of Science, CINAHL, and the Cochrane Database of Systematic Reviews and Google Scholar) were searched without limits, with the assistance of a senior librarian specialized in Health Sciences database searches. Human, in vivo studies that radiographically compared root resorption following fixed orthodontic treatment in root-filled and vital teeth were selected for full article review. Additionally, the bibliographies of the finally selected articles were hand searched to identify any relevant publications that were not identified by electronic searches. The lowest levels of evidence accepted for inclusion were case controls or cohort studies. Two authors independently reviewed and extracted data from selected studies. Results: A total of 165 original articles were identified from electronic database searches and 2 from hand searches. Once selection criteria were applied, only four articles met all inclusion criteria, and individual analysis of the selected articles was undertaken. Conclusions: Based on available evidence, root-filled teeth do not appear to be more susceptible to OIEARR than their analogous vital teeth.

Objective: To compare the changes in incisor inclination between two compliance-free Class II correction protocols for the treatment of mild to moderate Class II malocclusions. Materials and Methods: Among Class II malocclusion patients a total of 38 consecutive patients treated with the Xbow appliance and later with full brackets (XB) were compared to 36 consecutive patients treated with Forsus connected to the archwire while on full brackets (FO). Evaluated cephalometric variables were overjet, overbite, skeletal Class II, lower incisor inclination, and upper incisor inclination. Factors that were analyzed were gender, treatment type, age at start of treatment (T1), and treatment length. Independent t-tests, x 2 , multiple analysis of variance, and Pearson correlations were applied. Results: No differences in incisor inclination between both treatment protocols were identified. At T1 no statistical difference for any cephalometric variable was demonstrated with regard to gender and treatment type. Gender was also not associated with a different treatment time or age at T1. The mean treatment time was 24.2 months for XB and 30.2 months for the FO group (P 5 .037). XB patients averaged 10 fewer months of fixed edgewise appliances compared to FO patients. Neither gender nor treatment type had any influence on the changes of the evaluated dependent variables between T1 and the end of treatment. Lower incisors proclined more the longer the treatment (P 5 .005). Both overjet and upper incisor inclination were affected by age at T1 (P 5 .001 and P 5 .014, respectively).