Effect of ibuprofen and low-intensity pulsed ultrasound on the reduction of pain after initial archwire placement: a double-blind randomized clinical trial / Efecto del ibuprofeno y el ultrasonido pulsado de baja intensidad en la reducción del dolor después de la colocación inicial del arco de ortodoncia: un ensayo clínico aleatorizado doble ciego

Objective: This study aimed to compare the effect of ibuprofen and low intensity pulsed ultrasound (LIPUS) on the reduction of pain after the placement of initial archwire in orthodontic patients. Material and Methods: This double-blind clinical trial study was carried out on 60 female candidates for fixed orthodontic treatment referring to the Orthodontic Department of School of Dentistry in Mashhad University of Medical Sciences, Mashhad, Iran, during 2015-2016. The subjects were divided into four groups of ibuprofen, LIPUS, placebo, and mock LIPUS. A questionnaire and a rectangular and flexible cubic silicone were given to each patient to record the severity of pain based on the visual analog scale at specified time points (i.e., 2 h, 6 h, at bedtime, 2nd, 3rd, and 7th days after archwire placement) when biting the silicone block with the anterior and posterior teeth and without biting at all. Repeated measures analysis of variance was used in order to compare the pain severity at different time points. Results: The comparison of pain severity at various time points showed that the highest and lowest mean scores of pain were reported at bedtime and seven days after the intervention (p<0.001). In each of the three conditions (i.e., biting the silicone block with the anterior and posterior teeth and without biting the teeth) at six time points (i.e., 2 h, 6 h, at bedtime, 2nd, 3rd, and 7th days following archwire placement), no significant difference was observed in the severity of pain (p>0.05). Conclusion: In conclusion, LIPUS (with a frequency of 1 MHz and an intensity of 100 mW) and ibuprofen have no significant effects on reduction of the pain severity at different time points and various conditions in orthodontic patients.

Objetivo: Este estudio tuvo como objetivo comparar el efecto del ibuprofeno y el ultrasonido pulsado de baja intensidad (LIPUS) en la reducción del dolor después de la colocación del arco inicial en pacientes de ortodoncia. Material y Métodos: Este estudio de ensayo clínico doble ciego se llevó a cabo en 60 candidatas a tratamiento de ortodoncia fija referidas al Departamento de Ortodoncia de la Facultad de Odontología de la Universidad de Ciencias Médicas de Mashhad, Mashhad, Irán, durante 2015-2016. Los sujetos se dividieron en cuatro grupos: ibuprofeno, LIPUS, placebo y LIPUS simulado. Se entregó un cuestionario y un bloque de silicona cúbica rectangular y flexible a cada paciente para registrar la intensidad del dolor según la escala analógica visual en puntos de tiempo específicos (es decir, 2 h, 6 h, hora de acostarse, 2do, 3er y 7mo día después de la colocación del arco) al morder el bloque de silicona con los dientes anteriores y posteriores, y sin morder en absoluto. Se utilizó el análisis de varianza de medidas repetidas para comparar la intensidad del dolor en diferentes momentos.Resultados: La comparación de la intensidad del dolor en varios puntos de tiempo mostró que las puntuaciones medias de dolor más altas y más bajas se informaron a la hora de acostarse y siete días después de la intervención (p<0,001). En cada una de las tres condiciones (es decir, al morder el bloque de silicona con los dientes anteriores y posteriores, y sin morder) en seis momentos (2 h, 6 h, antes de acostarse 2do, 3er y 7mo día después de la colocación del arco), no se observó diferencia significativa en la severidad del dolor (p>0.05).Conclusión: En conclusión, LIPUS (con una frecuencia de 1 MHz y una intensidad de 100 mW) y el ibuprofeno no tienen efectos significativos en la reducción de la severidad del dolor en diferentes puntos de tiempo y diversas condiciones en pacientes de ortodoncia.

Long-Term Stability of Alveolar Bone Graft in Cleft Lip and Palate Patients: Systematic Review and Meta-Analysis.

OBJECTIVE: Alveolar bone grafts are the golden standard in treating patients with oral cleft and hence, the long-term success of this treatment is the subject of many studies. The aim of this study was to systematically review literature that examined the long-term stability of alveolar bone grafting in patients with cleft lip and palate. METHODS: In this study, data was collected via a comprehensive search of random and nonrandom studies evaluating the success of bone grafts in patients with cleft lip and palate in ISI Web of Science, EMBASE, Scopus, Medline, and Cochrane Central Register of Controlled Trials from the beginning until July 3, 2020. Also, a search was conducted for ongoing studies in the trial registry and a hand search of related gray literature and references of the relevant studies. The relevant data of the included studies were extracted using predefined extraction forms. Meta-analysis was performed using inverse-variance for calculating the pooled outcome of outcome measures. The pooled mean success rate of alveolar bone graft and mean difference of cleft volume after 1 year was presented as the outcome of the analysis. RESULTS: Eight studies (1 randomized clinical trial study and 7 controlled prospective studies) were included in this meta-analysis. The results of the analyses showed that the total percentage of secondary alveolar success in the follow-up period of at least 1 year according to the Bergland index was 76.52% (pooled success = 76.52%, 44.92-98.10). Also, bone defect in the cleft area reduced significantly after bone grafting (MD = 0.62 cm3, 0.48-0.75, P < 0.00001). The total percentage of bone filling after 1 year and according to CBCT (cone beam computed tomography) was about 63.38%, and the rate of definite natural eruption of canine within the graft was 80.89%. CONCLUSIONS: The total success rate of secondary alveolar bone grafting in the follow-up period of at least 1 year was clinically significant and alveolar bone grafting significantly reduced bone defect volume. Also, there was no difference in the amount of bone remaining after 1 year in patients whose canine had erupted through the grafted bone and in those whose canine had not erupted.

Sol-gel synthesis of amorphous calcium phosphate nanoparticles in brown rice substrate and assessment of their cytotoxicity and antimicrobial activities.

OBJECTIVE: This study intended to perform a synthesizing procedure for amorphous calcium phosphate (ACP) through a green template by the usage of brown rice (BR). MATERIALS AND METHODS: ACP nanoparticles were obtained by application of a sol-gel method and comprehensively characterized using X-ray powder diffraction (XRD), zeta potential, fourier-transform infrared spectroscopy (FTIR), field emission scanning electron microscope (FESEM), and atomic force microscopy (AFM). Cytotoxic activity of ACP was evaluated in human epithelial type 2 (HEp-2) cell lines. The antibacterial effects of nanoparticles were appraised against Gram-positive Streptococcus mutans and Enterococcus faecalis. RESULTS: The procedures for the evaluation of the characterization outcomes, dispersion, and stability of our product were confirmed by observing the smooth and uniformed surfaces of ACP. The zeta potential value of the synthesized sample was -22 mV, which indicates its acceptable stable condition caused by electrostatic repulsion. The cytotoxicity of the ACP nanoparticles was investigated in HEp-2 cells, and results showed no cytotoxicity for the synthesized nanoparticles. Also, the obtained minimum inhibitory concentration (MIC) of ACP nanoparticles in opposition to S. mutans and E. faecalis was 15 and 20 µg/ml, respectively, indicating the resistance of E. faecalis in comparison to S. mutans and MBC for synthesized nanoparticles against S. mutans and E. faecalis strains was 20 and 25 µg/ml. CONCLUSION: The present study showed that this compound has no toxicity on the examined cell line. Also, the antibacterial properties of the synthesized ACP were approved by the obtained data, which enables the application of this material for therapeutic purposes in the pharmaceutical industry.

Comparison of the High Cycle Fatigue Behavior of the Orthodontic NiTi Wires: An in Vitro Study

Abstract Objective: To compare the high-cycle fatigue behavior of four commercially available NiTi orthodontic wires. Material and Methods: Twelve NiTi orthodontic wires, round, 0.016-in, three per brand, were selected and divided into four groups: G1 - Heat-activated NiTi, G2 - Superelastic NiTi, G3 - Therma-Ti, and G4 - CopperNiTi. The atomic absorption spectrometry method was used to determine the chemical composition of investigated NiTi wires. We also performed a fatigue test at three-point bending using a universal testing machine for 1000 cycles in a 35 °C water bath. For the first and thousandth cycle, the average plateau load and the plateau length were determined in the unloading area of the force versus displacement diagram. In addition, we calculated the difference between the average plateau load of the first and thousandth cycle (∆F), as well as the difference between the plateau length of both cases (∆L). Results: According to our results, there were no significant differences between the average plateau load of the first and thousandth cycles of each group (p>0.05) and in the plateau length of the first and thousandth cycles of the groups (p>0.05). Conclusion: There were no significant differences between the groups changing the superelasticity property after high-cycle fatigue.

Effect of the addition of Chitosan and TiO2nanoparticles on antibacterial properties of an orthodontic composite in fixed orthodontic treatment: a randomized clinical trial study.

Due to the existing demands for methods independent of patient co-operation in preventing and overcoming the incidence of white spot lesions (WSLs) and caries in fixed orthodontic treatments, several studies have considered the modification of orthodontic composites using antimicrobial nanomaterials. In this regard, the aim of this study is to investigate the effect of the addition of chitosan nanoparticles (NPs) and TiO2NPs onStreptococcus mutans(S. mutans) counts and the enamel mineral content in fixed orthodontic patients. A double-blind randomized clinical trial study was carried out in 24 patients (i.e., 48 upper second premolars and 48 maxillary lateral incisors) who were candidates for fixed orthodontic treatment. In the case of the control group, the bracket was bonded to the tooth with an orthodontic adhesive (Transbond XT, 3M Unitek, USA) while, in the experimental group, the bracket was bonded to the tooth with Transbond XT containing 1% chitosan NPs and 1% TiO2NPs. For the maxillary lateral incisor and upper second premolar teeth, theS. mutanscounts around the brackets were measured, through the usage of real-time PCR, at the time points of 1 day, 2 months, and 6 months after bonding the brackets to the tooth. Furthermore, the enamel mineral content measurement was also performed around the brackets at 1 day, 2 months, and 6 months after bonding the brackets to the tooth. TheS. mutanscounts were analyzed using Friedman and Mann-Whitney U tests. The Repeated measures ANOVA test and Independent samples T-test were also applied, in order to evaluate the mineral content. According to the results, there was a significant reduction in theS. mutanscounts of experimental group at the time points of 1 day, 2 months, and 6 months in both maxillary lateral incisor and upper second premolar teeth. However, we did not observe any significant differences in the control group between the reports at 1 day, 2 months, and 6 months in both maxillary lateral incisor and upper second premolar teeth. The outcomes of this study indicate that, with regard to maxillary lateral incisor teeth, there were no significant differences between the results of the experimental group and control group at the time points of 1 day, 2 months, and 6 months. Furthermore, with respect to the upper second premolar teeth, no significant differences were observed between the two groups at 1 day and 2 months; however,S. mutanscounts were significantly lower in the experimental group than in the control group at the time point of 6 months. Moreover, our gathered data confirmed the absence of any significant differences between the experimental group and control group, in terms of enamel mineral content, at the time intervals of 1 day, 2 months, and 6 months. In conclusion, the incorporation of chitosan NPs and TiO2NPs in orthodontic composites induces an antibacterial property in the resultant adhesive to be used for fixed orthodontic treatment.

Effects of fluoride versus amorphous calcium phosphate solutions on enamel microhardness of white spot lesions: An in-vitro study.

BACKGROUND: Development of white spot lesions around orthodontic fixed orthodontic appliances is a common finding, especially in patients with poor oral hygiene. One of the conservative interventions for regression of these lesions is using chemical solutions. The current study aimed to compare the effectiveness of fluoride and amorphous calcium phosphate (ACP) on microhardness improvement of affected enamel. MATERIAL AND METHODS: Forty-five intact human incisor teeth were selected and randomly divided into 3 groups of 15. Fluoride group, ACP group and artificial saliva group (control group). Inducing of white spot lesion was done by PH-cycling model. Samples of the first and second group were submerged into 0.05% fluoride and 0.05% ACP solutions respectively for one minute a day. The rest of the time, all specimens were put in artificial saliva, which was incubated in 37 °c temperature. Microhardness of specimens was assessed by Vickers microhardness test in three stages: 1: Baseline microhardness assessment that was done before induction of white spot lesion, 2: Secondary microhardness assessment that was done after induction, 3: Final microhardness assessment that was done after chemical treatment. The SPSS 11.5 software was used for statistical analysis and p< 0.05 was considered as significant. RESULTS: Microhardness of specimens in the fluoride and ACP groups had significantly improved after the treatment (between secondary assessment and final assessment). In the control group, no significant improvements were observed. In final assessment, there were significant differences between the ACP and control groups, but no significant differences were found neither between the fluoride and ACP, nor the Fluoride and control groups. CONCLUSIONS: According to the current study, both 0.05% ACP and 0.05% fluoride solutions enhanced enamel micro-hardness in treatment of white spot lesion. Key words:Microhardness, amorphous calcium phosphate, fluoride, white spot lesion.

Evaluation of the Relationship Between Morphology, Volume, and Density of the Mandible and Dentofacial Vertical Dimension Using Cone Beam Computed Tomography

Abstract Objective: To evaluate the relationship between mandibular shape, mandibular bone density, cortical bone thickness, and condylar volume and facial height using a cone-beam computed tomography (CBCT). Material and Methods: Fifteen female patients (16-25 years old) were included in this study. The following measurements were performed on CBCT radiographs; inter-canine and inter-molar width of the mandible at three vertical points (alveolar crest, apex and basal bone), mandibular cortical bone thickness in disto molar and canine sections, bone density of the mandibular body and condylar volume. Afterward, subjects were divided into short face, normal and long face groups according to the Frankfort-mandibular plane angle (FMA) measured on lateral cephalograms obtained from CBCTs. Data were analyzed using Pearson correlation, one-way ANOVA, and post-hoc analysis Results: The inter-canine width of the mandible at the apical point in long face subjects was greater than in the other groups. Likewise, the cortical bone thickness was significantly higher in long face patients compared to the short face and normal subjects. There was no statistically significant difference in mandibular density or condylar volume between patients with various vertical heights (p>0.1) Conclusion: Vertical growth pattern is correlated with mandibular morphology to some extent.

An In Vitro Study on the Effect of Amorphous Calcium Phosphate and Fluoride Solutions on Color Improvement of White Spot Lesions.

The ability of remineralizing agents to improve the color of white spot lesions (WSL) is an important aspect that should be investigated. The aim of this study was to evaluate the effects of 0.05% amorphous calcium phosphate (ACP), 0.5% ACP, and 0.05% fluoride solutions, as well as artificial saliva on the color improvement of white spot lesions (WSLs). In this in vitro study, 50 human premolar teeth were randomly classified into five groups. At baseline, all the samples were assessed by using a colorimeter (E0). Then, white spot lesions were induced on the surface of the teeth by means of a pH-cycling model, and the colorimeter was used again (E1). Afterwards, samples of the 1st and 2nd groups were kept in 0.05% ACP and 0.5% ACP solutions for 1 min/day, respectively. The 3rd group specimens were placed in 0.05% fluoride solution for 1 min/day. The other two groups were kept in artificial saliva and distilled in water separately. All the samples were assessed by the colorimeter for a third time (E2). We found no significant difference between the groups in ∆E1. There was also no significant difference among 0.05% ACP solution, 0.5% ACP solution, 0.05% fluoride solution, and artificial saliva considering ∆E2. However, a significant difference was noted between the above-mentioned solutions and distilled water in ∆E2. With respect to ∆E3, there were considerable differences between ACP solution and artificial saliva. The same results were obtained for the difference between fluoride solution and artificial saliva. However, no significant difference was found among 0.05% ACP, 0.5% ACP, and 0.05% fluoride solutions in terms of ∆E3. In Conclusion, ACP is as effective as fluoride in the color improvement of WSLs and the recommended treatment for this purpose is daily use of 0.05% ACP, 0.5% ACP or 0.05% fluoride solutions.

A comparative assessment of enamel mineral content and Streptococcus mutans population between conventional composites and composites containing nano amorphous calcium phosphate in fixed orthodontic patients: a split-mouth randomized clinical trial.

OBJECTIVES: The aim of this 'split-mouth design' trial was to evaluate the effect of the nano amorphous calcium phosphate (NACP) containing composite on enamel mineral contents and streptococcus mutans population in fixed orthodontic patients. DESIGN, SETTING, PARTICIPANTS, AND INTERVENTION: Randomized, prospective, single-center controlled trial. Twenty-four patients between the ages of 13-18 years participated in this study. The control and test sides were randomly selected by a coin toss (1:1 ratio). On the control side orthodontic brackets were bonded on the buccal surfaces of upper premolars and laterals using an orthodontic composite (Transbond XT), and on the study side NACP-containing composite was used. Outcome measures were the mineral content around the brackets and S.mutans count. The later were calculated in the plaque around the brackets by real-time PCR at 3 months, and 6 months after the initiation of treatment. All stages of the study were blind using coding system. Paired t-test and repeated measurements were used for data analysis. RESULTS: In the third and sixth month, the bacterial population was significantly lower in the study side than the control side (P = 0.01 and 0.000).The mineral content of the study side was significantly higher than the controls, 6 months after brocket bonding (P = 0.004). There were no significant differences between the premolars and lateral teeth for all measurements. LIMITATIONS: This research was performed in a single-center by one experienced clinician. CONCLUSION: NACP-containing composites have the potential to inhibit mineral content loss and S.mutans colonization around orthodontic brackets during fixed orthodontic treatments. TRIAL REGISTRATION: This trial was not registered. PROTOCOL: The protocol was not published before trial commencement.

Evaluation of health related quality of life changes after initial orthodontic treatment.

PURPOSE: To evaluate the changes of Oral Health Related Quality of Life (OHRQoL) in patients after the placement of a fixed orthodontic appliance. MATERIALS AND METHODS: This prospective study consisted of 148 adolescents (97 girls and 51 boys) between the ages of 14 and 17 who were patients of an orthodontic clinic. OHRQoL was assessed by a modified questionnaire that evaluated four domains: oral symptoms, functional limitations as well as emotional and social well-being in three time frames: before bonding and banding (T(0)), two months after initiating orthodontic treatment (T(1)) and six months after initiating orthodontic treatment (T(2)). The repeated measures test was used to compare the relative changes of OHRQoL among the different time frames. RESULTS: There were no significant differences between the levels of OHRQoL and its domains for boys or girls at any time point. The overall level of OHRQoL decreased significantly at T(1) relative to T(0); however, the emotional well-being domain improved at T(1) in comparison to T(0). At T(2), the OHRQoL level increased significantly relative to T(0) in all domains. CONCLUSION: The patients' quality-of-life level decreased by initiating orthodontic treatment; however, during that period, emotional well-being increased. As orthodontic treatment progressed, the quality of life level increased.

Evaluation of relationship between oral health-related quality of life and occlusion traits among female adolescents.

BACKGROUND: The aim of this study was to determine the impact of malocclusions on oral health-related quality of life (OHRQOL) among female adolescents. MATERIALS AND METHODS: This is an observational cross-sectional descriptive study. A total of 129 female students with age ranges between 14 and 17 years old were randomly selected from Mashhad (Iran) high schools and were asked to fill out an OHRQOL questionnaire included in four parts: Oral symptoms, functional limitations, emotional well-being and social well-being. Each participant was clinically examined to assess her malocclusion according to the index of complexity, outcome and need (ICON) and finally the data were entered to SPSS 11.5 and the relation between these two variables was assessed with Pearson correlation test. P < 0.05 was considered as statistically significant. RESULTS: There was statistically significant correlation between ICON scores and quality of life (P = 0.0176). Being separately assessed, among four parts of the questionnaire, only emotional well-being was significantly correlated with the ICON score (P < 0.05). CONCLUSION: Malocclusions play a vital role in OHRQOL. However, in female adolescents among four parts of OHRQOL, emotional well-being had significant relationship with malocclusions.

Which has a Greater Influence on Smile Esthetics Perception: Teeth or Lips?

INTRODUCTION: The aim of this study was to evaluate the role of teeth and lips in the perception of smile esthetics. MATERIALS AND METHODS: Thirty women, ranging between 20 and 30 years of age, all with Class I canine and molar relationships and no history of orthodontic treatment, were chosen. Five black and white photographs were taken of each participant in a natural head position while smiling. The most natural photo, demonstrating a social smile, was selected. Two other photographs were also taken from a dental frontal view of each subject using a retractor, as well as a lip-together smile. Three groups of judges including 20 orthodontists, 20 restorative specialists, and 20 laypersons were selected. The judges were then asked to confirm the esthetics of each picture on a visual analogue scale. An analysis of variance (ANOVA) and the Pearson correlation test were used for statistical analysis. RESULTS: For the orthodontists group, correlation between the scores given to the full smile and each of its components was significant (α=0.05), with equal correlation of each component with the full smile. In contrast to laypersons, the correlation between the scores given to the full smile and each of its components among restorative specialists was significant. CONCLUSION: For orthodontists and restorative specialists, esthetic details and the components of the smile (teeth and perioral soft tissues) were important in esthetics perception. In contrast, laypersons perceived no effect of esthetics detail or smile components.

Pain reduction after initial archwire placement in orthodontic patients: a randomized clinical trial.

INTRODUCTION: The aim of this study was to compare the efficacy of ibuprofen, viscoelastic bite wafers, and chewing gum in reducing orthodontic pain. METHODS: This randomized clinical trial included 50 girls between the ages of 13 and 18 years classified into 5 groups of 10 each: placebo, ibuprofen (400 mg), chewing gum, soft viscoelastic wafer, and hard viscoelastic wafer. The patients in each group received 1 method immediately after placement of the initial archwires and every 8 hours if they experienced pain. Pain perception was recorded by the patients while chewing, biting, fitting front teeth, and fitting posterior teeth at 2 hours, 6 hours, bedtime, 24 hours, 2 days, 3 days, and 7 days after archwire placement, using a visual analog scale. Analysis of variance (ANOVA) and Tukey tests were used for data analysis. RESULTS: There were significant differences in pain perception of chewing function between the placebo group and the chewing-gum group at 24 hours and 7 days, and between the placebo group and the hard-viscoelastic group on the day 7 (P <0.05). Also, there were significant differences between the placebo group and the soft-viscoelastic group, and between the placebo group and the hard-viscoelastic group in pain severity when fitting posterior teeth at 6 hours (P <0.05). At other times and with other functions, no significant differences were recorded. CONCLUSIONS: Both chewing gum and viscoelastic bite wafers are effective for pain reduction in orthodontic patients and can be recommended as suitable substitutes for ibuprofen.

Does ultra-pulse CO(2) laser reduce the risk of enamel damage during debonding of ceramic brackets?

This study seeks to evaluate the enamel surface characteristics of teeth after debonding of ceramic brackets with or without laser light. Eighty premolars were bonded with either of the chemically retained or the mechanically retained ceramic brackets and later debonded conventionally or through a CO(2) laser (188 W, 400 Hz). The laser was applied for 5 s with scanning movement. After debonding, the adhesive remnant index (ARI), the incidence of bracket and enamel fracture, and the lengths, frequency, and directions of enamel cracks were compared among the groups. The increase in intrapulpal temperature was measured in ten extra specimens. The data were analyzed with SPSS software. There was one case of enamel fracture in the chemical retention/conventional debonding group. When brackets were removed with pliers, incidences of bracket fracture were 45% for the chemical retention, and 15% for the mechanical retention brackets. No case of enamel or bracket fracture was seen in the laser-debonded teeth. A significant difference was observed in ARI scores among the groups. Laser debonding caused a significant decrease in the frequency of enamel cracks, compared to conventional debonding. The increase in intrapulpal temperatures was below the benchmark of 5.5 °C for all the specimens. Laser-assisted debonding of ceramic brackets could reduce the risk of enamel damage and bracket fracture, and produce the more desirable ARI scores without causing thermal damage to the pulp. However, some augmentations in the length and frequency of enamel cracks should be expected with all debonding methods.

Do malocclusions affect the oral health-related quality of life?

PURPOSE: The aim of this study was to assess the relationship between untreated malocclusions and oral health-related quality of life (OHRQOL) in male adolescents of Mashad (Iran) high schools. MATERIALS AND METHODS: In this observational cross-sectional descriptive study, 120 male students were randomly selected among Mashad (Iran) high schools. These students filled out an oral health-related quality of life questionnaire (the modified version of CPQ), and then they were clinically examined to determine their malocclusions according to the Index of Complexity, Outcome and Need (ICON), and finally the relationship between these two variables was assessed with the Pearson correlation test. RESULTS: There was a statistically significant relationship between ICON scores and the quality of life levels (P < 0.01). The assessment of four sections of the questionnaire showed that among these four sections (oral symptoms, functional limitations, emotional well-being, social well-being), only oral symptoms were significantly correlated with the ICON score (P < 0.05). CONCLUSION: Malocclusion plays an important role in the oral health-related quality of life. However, the relationship between emotional well-being, social well-being and malocclusions was not as strong as in previous studies.