The Influence of Various Adhesive Systems and Polishing Methods on Enamel Surface Roughness after Debonding of Orthodontic Brackets: A Three-Dimensional In Vitro Evaluation.

A slight alteration of the enamel surface is inevitable upon debonding of orthodontic brackets, adhesive removal, and finishing/polishing. The aim of this in vitro study was to compare two adhesives and three polishing methods by measuring enamel surface roughness using confocal laser scanning microscopy (CLSM). Brackets were bonded on 42 extracted human premolars using Transbond XT (Transbond group) or Fuji Ortho (Fuji group). After debracketing, adhesives were removed with a tungsten carbide bur, and surfaces were polished using Sof-Lex discs, a rotary brush with a prophylactic paste (Depural), or a prophylactic cup with two polishing pastes (n = 7 in each subgroup). Surface roughness (Sa, Sku, Sq, and Sz) was measured using CLSM and compared before treatment (T1), after debracketing and adhesive removal (T2), and after polishing (T3). The data were statistically analyzed using the Mann-Whitney U and Kruskal-Wallis tests with Bonferroni correction. The time required for adhesive removal was measured and compared using a two-sample t-test. Surface roughness at T2 increased compared to T1, but the difference was significant only for the Fuji group (p < 0.01). The time required to remove Transbond XT (94.1 ± 6.8 s) was significantly higher compared to Fuji (72.1 ± 5.9 s, p < 0.0001). Polishing with Sof-Lex discs resulted in lower surface roughness compared to T1 (p = 0.018). Using Depural and polishing pastes showed no significant difference in surface roughness compared to T1, except for a significant decrease in Sa and Sq for Transbond (p = 0.043) and in Sku for Fuji (p = 0.018) after polishing with Depural. In conclusion, the removal of Transbond took significantly longer, but there were fewer residues of composite resin on the enamel surface. Sof-Lex discs decreased enamel roughness, whereas enamel morphology and roughness were similar to the pre-treatment state after polishing with polishing pastes.

Comparison of spontaneous eruption and modified closed eruption technique with palatal traction in alignment of impacted maxillary central incisor teeth.

BACKGROUND: Central incisor impaction is a rare condition with potentially severe clinical and psychological implications for the patient. Treatment techniques vary according to the pretreatment situation and individual factors. The aim of this study was to compare the esthetic outcomes and treatment times between two different approaches. MATERIALS AND METHODS: In this retrospective study, thirty-one consecutive patients (13 boys, 18 girls; average age 9.5 ± 2.3 years) with a total of 34 impacted permanent upper central incisors were included in the study. Patients were divided into two groups according to method of treatment. Group A comprised patients in whom spontaneous eruption occurred after space opening (n = 12), and Group B comprised patients in whom teeth showed no eruption and required treatment with a modified closed eruption method with palatally oriented traction (n = 19). Treatment time and esthetic outcomes were assessed and compared between groups. RESULTS: The mean treatment time was 22.0 ± 6.7 months, and all teeth were successfully aligned. No statistically significant difference in average treatment time was found between groups in baseline characteristics (p > 0.05). The amount of attached gingiva was significantly smaller when compared to contralateral reference teeth in the closed eruption group (Group B; p = 0.03). However, no difference in amount of attached gingiva was found between both groups (p = 0.26). Additionally, no difference in the clinical crown length was found between groups (p = 0.27). CONCLUSION: The closed eruption method with palatal traction directed at the peak of the alveolar crest provided results comparable to the physiologic tooth eruption.

Study of Protein Conformational Dynamics Using Hydrogen/Deuterium Exchange Mass Spectrometry.

Intrinsic protein dynamics contribute to their biological functions. Rational engineering of protein dynamics is extremely challenging with only a handful of successful examples. Hydrogen/deuterium exchange coupled to mass spectrometry (HDX-MS) represents a powerful technique for quantitative analysis of protein dynamics. Here we provide a detailed description of the preparation of protein samples, collection of high-quality data, and their in-depth analysis using various computational tools. We illustrate the application of HDX-MS for the study of protein dynamics in the rational engineering of flexible loops in the reconstructed ancestor of haloalkane dehalogenase and Renilla luciferase. These experiments provided unique and valuable data rigorously describing the modification of protein dynamics upon grafting of the loop-helix element. Tips and tricks are provided to stimulate the wider use of HDX-MS to study and engineer protein dynamics.

Intrusion of overerupted molars with temporary anchorage devices before prosthetic reconstruction: A case report.

Extraction of teeth without adequate prosthetic rehabilitation frequently can lead to overeruption of opposing teeth, which may cause occlusal disturbances and complicate dental restoration. Equilibration with consequent need of endodontic treatment, surgical intrusion or extraction are often indicated as a remedy in such cases. The article proposes a method of orthodontic intrusion with the use of temporary anchorage devices as a predictable and less invasive option. Important clinical aspects of molar intrusion with respect to surrounding anatomical structures are also discussed.

Understanding orthodontists' decision making in relation to innovations from encounter to implementation: A qualitative study.

INTRODUCTION: High-quality scientific and technological advancements are necessary if quality improvement is to be achieved in orthodontic treatment. However, suboptimal research uptake in clinical practice and innovation adoption patterns that are not consistent with scientific evidence suggest that a better understanding of the adoption behavior of clinicians is needed. This research aimed to explore the factors that influence orthodontists to adopt innovations into practice. METHODS: This was a qualitative study in which 9 semistructured in-depth interviews were conducted with orthodontists and third-year orthodontic residents. The interviews were digitally recorded, and field notes were taken. Data were professionally transcribed verbatim and deidentified. Thematic analysis was used to inductively generate codes and subsequent themes. This study was reported according to the consolidated criteria for reporting qualitative studies checklist. RESULTS: Six main themes emerged as facilitators or barriers to adoption. In addition, a sequence of events that took place from knowledge encounter through to implementation was described. Factors influencing adoption included: the perceived state of one's current practice; features of the encounter; attributes of the innovation; clinician's personality traits; practice management; and external influences relating to the professional community, patients, and marketing pressures. CONCLUSIONS: The study provides an insight into what orthodontists consider in their decisions to adopt new knowledge into clinical practice. The findings can help clinicians navigate decision making around innovation adoption by increasing awareness of the factors that influence this process to ensure that switching practice leads to quality improvement.

The effect of different bonded retainer wires on tooth mobility immediately after orthodontic treatment.

OBJECTIVES: This study aimed to compare the immediate influence of four commonly used retainer wires on tooth mobility following orthodontic treatment with fixed appliances. MATERIALS AND METHODS: Eighty patients after orthodontic treatment were assigned to four study groups (n = 20 in each group). Groups were provided with directly bonded fixed retainers-0.0150″ (group A), 0.0175″ (group B), 0.016 × 0.022″ (group C), and 0.0215″ (group D). Tooth mobility was measured using the Periotest device at two times-after removal of fixed appliance (T1) and after bonding of the retainer (T2). Values of tooth mobility, 'Periotest values', were analysed between groups and compared with the physiologic tooth mobility in a control group of untreated patients (n = 65). Kruskal-Wallis H, Mann-Whitney U, Dunn's test, Fisher's exact test, and binary logistic regression tests were used to analyze the data. RESULTS: Tooth mobility after orthodontic treatment was significantly increased. While canines remained within normal range of tooth mobility, values for incisors increased on average to the first degree of tooth mobility (slight mobility). Logistic regression analysis identified age as a significant predictor for increased tooth mobility (P = 0.032) with odds ratio 1.065 (95% CI 1.005-1.128), with mobility increasing with age. After bonding of the retainer in all four groups, the tooth mobility was reduced to values which were not significantly different form normal physiological values found in the control group (P > 0.05). There were no differences in the amount of change or in tooth mobility values at T2 between the different types of bonded retainers. LIMITATIONS: Age of subjects in the control group was significantly higher than that in the study groups. An alternation method was used instead of randomization to distribute the four different types of retainers. CONCLUSIONS: All of the retainer wires were able to successfully reduce the increased tooth mobility caused by orthodontic treatment to normal levels. The values of tooth mobility after placement of retainers were within the range of physiologic tooth mobility.

Raw Cow Milk Protein Stability under Natural and Technological Conditions of Environment by Analysis of Variance.

Heat stability (HS) is substantial technology property of raw milk. Analysis of sources of HS variation and its regular monitoring can contribute to creating higher added value in the dairy industry. The goal of this analysis was to assess the practice sources of raw cow milk HS variability on the results of an extensive data set of bulk tank milk samples. There was implemented neither a compositional technology modification nor acidity adjustment of milk, just original raw milk was used for the analysis. A total 2634 HS analyses were performed, including other milk indicators, during three years of an experimental period. The log HS mean and standard deviation were 1.273654 ± 0.144189, equal to the HS geometric mean of 18.8 min. Explanation of the HS variability through the linear model used was 41.1% (p < 0.0001). According to the results of the variance analysis, the milk HS was influenced (p = 0.0033 and mostly <0.0001) by all the farm factors such as year; season; calendar month; altitude; total annual rainfall; herd size by the number of cows; milk yield; cow breed; type of milking; litter type in the stable; summer grazing application; farm effect. During the calendar months (p < 0.0001), milk HS values suggest similar seasonal dynamics with the somatic cell count, total count of mesophilic microorganisms, coli bacteria count and urea and lactose concentration and opposite configuration pattern to fat, crude protein, solids-not-fat and total solids content and milk freezing point depression. Here performed quantification of these effects by analyzing the variance may allow efficient raw milk selection to be processed into specific dairy products.

Fixed retention: pitfalls and complications.

Long-term stability of orthodontic treatment results is problematic. Long-term or even lifelong retention with bonded retainers is being increasingly used among clinicians. Bonded retainers can provide an efficient and attractive method of retention, particularly because they require minimal compliance from patients. However, the use of bonded retainers is associated with relatively frequent complications, such as detachments of the adhesive layer or wire fractures, as well as unexpected complications with potentially severe consequences with associated periodontal and general health risks. It is imperative that the whole dental team are aware of these pitfalls and complications, and appreciate how to minimise and address these.

The effect of extended lactation on parameters of Wood's model of lactation curve in dairy Simmental cows.

OBJECTIVE: This study was focused on the estimation of parameters of Wood's model and description of the lactation curve using the cows which were lactated over 24 months on the first lactation. METHODS: The database included 1,333 pure-bred dairy Simmental primiparous cows which lactated for 24 months (732 days). The initial dataset entering the procedure of assessment of parameters of Wood's function included 35,826 milk yield records. Milk yield was recorded throughout lactation, with the earliest record taken on day 6 and the latest on day 1,348 of lactation. This dataset was used for the assessment of parameters a, b, c of Wood's model using the non-linear statistical procedure. These parameters were estimated for different length of lactation. The assessed parameters were used for calculation of some characteristics of lactation curves. RESULTS: The lowest value of a parameter (15.2317) of Wood's model of lactation curve was found out in lactations up to 305 days long, contrary to b and c parameters which were highest in those lactations (0.1029 and 0.0015, respectively). The maximum value of a parameter (17.4329) was found out in lactations up to 640 days long, unlike b and c parameters which were minimal in those lactations (0.0603 and 0.0010, respectively). CONCLUSION: It can be concluded that the parameters of Wood's model and the shape of lactation curve are changing with the growing number of milk yield records. Also, the assessed parameters revealed a significant milk production potential after 305 days of lactation.

Windbreak Efficiency in Agricultural Landscape of the Central Europe: Multiple Approaches to Wind Erosion Control.

Windbreak is one of the key factors for making the agriculture systems successful through reduced wind erosion, improved microclimate, increased biodiversity, and production potentiality of timber and agricultural crops. Even though windbreak occupies only a small part of agricultural landscape, its advantages on the ecological and economical perspective are quite high. This study evaluated the effects of three windbreak types on the wind erosion control in relation to their structural diversities, wind-speed reduction, and optical porosities in the central part of the Czech Republic. Diversity in the windbreak was evaluated based on its species diversity, vertical structure, spatial pattern, and complexities. Wind speed was measured at the different distances on the leeward side of the windbreak and one station placed on the windward side as a control. Windbreak characteristics were described by terrestrial photogrammetry method using the values of optical porosity. The timber volume of the windbreaks with rich biodiversity species ranged from 224 to 443 m3 ha-1height of the windbreak on the. Results of the windbreak efficiency showed significantly closer relationship between optical porosity and structural indices. The optical porosity significantly correlated with wind-speed reduction, especially in the lower part of the windbreak. A significant dependency of the windbreak efficiency on the tree dominant height was also observed for each windbreak type. The most significant effect on the wind-speed reduction in terms of structural indices had total diversity index and Arten-profile index describing vertical structures, which are recommended together with the optical porosity to evaluate the windbreak efficiency in controlling wind erosion.

Heavy water enhancement of fluorescence signal in reversed-phase liquid chromatography.

Liquid chromatography with fluorescence detection has been used in analyses demanding high sensitivity and selectivity. As majority systems rely on reversed-phase columns with water being the main component of the mobile phase, fluorescent compounds with emission maxima higher than 500 nm might be dynamically quenched. A simple replacement of H2O with D2O enhanced the sensitivity for selected compounds by 10-200%. Affected compounds included an anti-cancer drug doxorubicin, a luminescent probe fluorescein, and naturally occurring forms of vitamin B2. Similar levels of enhancement were obtained by fluorescence spectrometry. Such simple yet effective approach may greatly improve HPLC analyses coupled to fluorescence detection.

Alumazene Reactivity with Quinolinols - Addition and Substitution Reactions on the Al3N3 Ring.

Molecular structures of two compounds obtained in reactions of alumazene [DippNAlMe]3 (1, Dipp = 2,6-i-Pr2C6H3) with substituted quinolinols have been elucidated by the single-crystal X-ray diffraction analysis. Quinolin-8-ol (Hq) provides a dinuclear complex [(DippNH)2Al2Me2(q)2] (2) with a central Al2O2 ring and five-coordinate Al atoms. The compound 2×THF crystallizes in the orthorhombic Pbca space group. The molecular structure of a mononuclear complex [(DippNH)Al(Meq)2] (3) obtained in the reaction of 1 with 2-methylquinolin-8-ol (HMeq) possesses a five-coordinate Al center. The structure was solved in a triclinic cell P-1. The dinuclear complex 2 can be considered as a model product of alcohol addition on the formal Al-N double bond, while the mononuclear complex 3 represents subsequent reaction of remaining Al-Me moiety with proton. Both complexes 2 and 3 are highly luminescent showing emission around 500 nm in solid state.

Unexpected complications associated with mandibular fixed retainers: A retrospective study.

INTRODUCTION: The purposes of this retrospective study were to describe the types of unexpected complications associated with mandibular fixed retainers and to assess their prevalences and possible etiologic causes. METHODS: A total of 3500 consecutive patients (1423 male, 2077 female) treated with fixed appliances and a mandibular fixed retainer as a part of the retention protocol were screened during the retention period (2008-2013) for unexpected complications. Thirty-eight subjects (12 male, 26 female; mean age, 20.7 ± 8.9 years) with unexpected complications were identified and assigned to the unexpected complications group and compared with a randomly selected control group of 105 subjects (43 men, 62 women; mean age, 29.5 ± 9.7 years) without unexpected complications. Relationships between unexpected complications and cephalometric and clinical variables were evaluated. RESULTS: An opposite inclination of the contralateral canines (twist effect) was found in 21 subjects. In 89.5%, the left canines were tipped buccally. A torque difference of 2 adjacent incisors (X effect) was identified in 12 patients. In 5 subjects, nonspecific complications were noted. Subjects in the unexpected complications group were significantly younger at debonding (P = 0.03) and had higher mandibular plane angles (P <0.0001) and increased pretreatment ventral positions of the mandibular incisors (P = 0.029). No differences were found between the groups with regard to treatment duration, wire type, failure rate, treatment changes in incisor proclination, or intercanine distance. CONCLUSIONS: Unexpected complications of mandibular fixed retainers are relatively rare. Facial divergence was identified as a possible predictor. However, the etiology is most likely multifactorial. Strong asymmetry among the patients with the twist effect suggests that the mechanical properties of retention wires may play a role and should be examined in the future.

Movement of the patient and the cone beam computed tomography scanner: objectives and possible solutions.

OBJECTIVE: This study aimed (1) to determine whether scanner arm rotation causes significant movement of the head restraint and (2) to measure patient movement and its variation during the scan. STUDY DESIGN: The iCAT scanner and a high-speed camera were used. The 40 patients were divided into 2 groups: the open-eyed group and the blindfolded group. RESULTS: The mean level of head restraint movement was 0.130 mm, with a significantly higher level at the beginning, probably owing to the accelerating arm. Mean movement of patients was 1.135 mm and 1.119 mm in the open-eyed and blindfolded groups, respectively. Patient movement was also significantly higher at the beginning of the scan, when noise and vibrations are likely to surprise the patient. CONCLUSIONS: Patient instruction and a dry-run scan should be done by clinicians. Manufacturers should consider separating the seat and head restraint from the rest of the scanner to avoid vibration transfer.

Molar height and dentoalveolar compensation in adult subjects with skeletal open bite.

OBJECTIVE: To evaluate the skeletal and dentoalveolar components in adult subjects with skeletal open bite in the presence or absence of dental compensation. MATERIALS AND METHODS: The study sample included 69 adult female subjects who belonged to three groups according to skeletal vertical relationships and overbite. A total of 15 variables (5 angular, 10 linear) were evaluated. Values in the dentally compensated open bite group (COBG), the dentally noncompensated open bite group (NCOBG), and the control group with normal vertical skeletal relationships and overbite (CG) were compared by means of parametric statistics. RESULTS: The COBG and the NCOBG showed significantly greater incisor and molar heights in both jaws than the CG. No significant difference in upper or lower molar height was found between COBG and NCOBG. Incisor height was significantly greater in COBG than in NCOBG. Elongation in the incisor region was accompanied by significant narrowing of the lower anterior alveolar process in both skeletal open bite groups. Proclination of the upper incisors was significantly smaller in the COBG than in the other groups. CONCLUSIONS: Dentoalveolar components consisting of incisor elongation and inclination play a significant role in compensating for skeletal open bite configuration in adult subjects. Increased molar height is a common finding in adults with skeletal open bite.