The Effect of Different Soft Drinks on the Force Degradation of Conventional and Memory Orthodontic Elastic Chains: An In-Vitro Study.

Objectives: The aim of this study was to assess how different soft drinks affect the deterioration of conventional and memory orthodontic elastomeric chains. Materials and Methods: We used 500 five-loop segments of elastomeric chains, which were divided into two equal groups of conventional and memory chains. The samples were kept in artificial saliva during the study period. Each group was further divided into 5 subgroups consisting of artificial saliva (controls), Coca-Cola®, non-alcoholic beer (ISTAK®), and carbonated and non-carbonated yoghurt-based drinks (Alis®). Treatment with the soft drinks consisted of immersion in the test liquids twice a day for 3 minutes each time. Force measurements were taken on days 1, 7, 14, 21, and 28. Data were analyzed using One- and three-way ANOVA tests, and independent t-test, with a significance level of 5%. Results: The mean initial force for the conventional and memory elastomeric chains was 3.34±0.112N and 2.49±0.209N, respectively. Conventional chains showed significantly greater degradation than memory chains (P<0.01). Soft drinks had a significant impact on force degradation for both types of chains at all time points (P<0.01). Coca-Cola® had the highest level of force degradation, while non-carbonated yoghurt-based drinks had the lowest (P<0.01). Conclusion: Based on the findings of this study, it is recommended that orthodontic patients choose non-carbonated yoghurt-based drinks during their treatment. Memory elastomeric chains may be more suitable for patients who consume large amounts of carbonated soft drinks, due to their lower amount of force degradation compared to conventional chains.

Evaluation of bond strength of orthodontic brackets using light- and chemical-cure adhesive systems over time: An in-vitro study.

AIMS: This study aimed to evaluate the bond strength of light- and chemical-cure adhesive systems over six months. MATERIALS AND METHODS: A total of 144 sound human maxillary first and second premolars were randomly divided into six groups according to the adhesive type (i.e., Transbond XT and Unite) and evaluation time. The groups were T0 (24-h group without thermocycling), T1 (24-h group with thermocycling), T2 (1-month group), T3 (2-month group), T4 (4-month group), and T5 (6-month group). The bond strength was then measured and the data were analyzed by SPSS software (version 23) through the independent t-test and one-way ANOVA. A P value less than 0.05 was considered statistically significant. RESULTS: The results of this study showed that shear bond strength of chemical-cure orthodontic adhesive (Unite, 15.37 MPa) at all-time points was significantly 1.37 times higher than that of the Transbond XT light-cure adhesive (11.15 MPa). Moreover, shear bond strength of self-cure adhesive (Unite) 1 month after debonding showed a significant difference with the 24-h group without thermocycling (P = 0.002), 24-h group with thermocycling (P = 0.008), and 6-month group (P = 0.016). The highest shear bond strength in both adhesives was observed at one month. Furthermore, the shear bond strength of Transbond XT light-cure adhesive one month after debonding showed a significant difference with the 24-h group without thermocycling (P = 0.000) and 24-h group with thermocycling (P = 0.000), as well as with the 2-month (P = 0.008), 4-month (P = 0.000), and 6-month groups (P = 0.016). CONCLUSION: Unite self-cure adhesive compared to Transbond XT light-cure adhesive has higher bond strength and is recommended for rebonding brackets in patients with multiple rebonds.

Effects of posterior intrusion using skeletal anchorage on treating anterior open bite: A systematic review and meta-analysis.

Background: Posterior intrusion with skeletal anchorage is one of the effective methods in the treatment of anterior open bite. Knowing the effects of posterior intrusion, the amount of possible molar intrusion using skeletal anchorage, and its impact on clinical and cephalometric indicators can help the clinician choose the optimal treatment method, especially in borderline surgical cases. Methods: In this systematic review, a series of articles were collected through a systematic search in databases, and the titles and summaries of all these articles were reviewed. After removing the irrelevant articles, the full texts of the related articles were read carefully, and their validity was evaluated. Only RCTs and observational studies that complied with PICO questions were included. The Cochrane Risk of Bias 2.0 (RoB 2), ROBINS-I, and GRADE were used to assess the risk of bias in the included studies. The relevant information on selected articles was extracted, and a meta-analysis was performed with Review Manager 5.4 software. Results: The meta-analysis revealed a significant average molar intrusion of 2.89 mm using temporary anchorage devices (TADs). A subgroup analysis showed that miniplates achieved greater intrusion (3.29 mm) compared to miniscrews (2.25 mm) (P=0.03). The level of applied force did not significantly affect the degree of intrusion. Dental parameters such as overbite and overjet were notably altered, with overbite increasing by 4.81 mm and overjet decreasing by 2.06 mm on average. As for the skeletal cephalometric characteristics, SNB, ANB, and SN-Pog increased while mandibular plane angle and lower anterior facial height (LAFH) decreased, and these changes were significant. Meanwhile, SNA and palatal angle changes were not significant. Conclusion: TADs have proved effective in achieving significant intrusion of maxillary molars, leading to marked improvements in dental and skeletal characteristics in patients with open bite malocclusion. Miniplates proved more effective in achieving greater intrusion.

Oral Health Literacy and COVID-19 Pandemic Anxiety and Concerns Among Iranian Orthodontic Patients.

OBJECTIVE: This study aims to evaluate the impact of the COVID-19 pandemic on orthodontic appointments, and the concerns and anxiety levels of orthodontic patients in Iran. METHODS: An anonymous 40-question questionnaire was sent online to the patients of private orthodontic clinics in 2 cities of Birjand, and Mashhad, capitals of Eastern provinces of Iran. Orthodontic patients of Mashhad dental school received the questionnaire as well. Descriptive statistics were reported, and the association between gender, oral health literacy (OHL), and adherence to orthodontic appointments and attendance, along with data on feeling, concern, and level of anxiety regarding quarantine/coronavirus pandemic were evaluated using the chi-square analysis. RESULTS: Three hundred twenty-four patients, with a mean age of 32.43 years, answered the questionnaire. Fifty-seven percent of participants said that they only left home for their daily requirements. Seventy-two percent of the participants reported feeling calm about the COVID-19 pandemic and its consequences. Most of the patients (74%) said that they would attend their orthodontic appointment in case of urgency, and 41% of patients declared that their greatest concern was the probability of a delay in completion of treatment. Forty-five percent of patients had adequate OHL. There was a significant association between OHL and willingness to attend orthodontic treatment, concerns regarding the impact of the pandemic on orthodontic treatment, and the frequency of daily teeth brushing. CONCLUSION: Women respected the quarantine more than men. Patients with higher OHL were more willing to attend their appointments, but only in case of an emergency, due to the outbreak of COVID-19. Women were more concerned and had better oral hygiene behaviors.

Evaluation of Divine Proportions in Face and Smile of Patients With Unilateral Cleft Lip and Palate.

INTRODUCTION AND AIM: The facial view of patients with cleft lip and palate greatly affects their psychological well-being and usually leads to introspection. The aim of this study was to compare the face and smile of cleft lip and palate patients and normal population with divine proportion. METHOD: In this retrospective study, 20 female patients (14-25 years) with unilateral cleft lip and palate, who referred to Orthodontic Department of Mashhad School of Dentistry, were selected. The control group consisted of 10 normal female persons with ideal face and normal occlusion. After scanning photographs of full face, profile, and smile views of them, the divine proportions were measured by Photoshop software. Then the data were entered into SPSS software version 22 and analyzed using 2 sample independent t test. P value less than 0.05 were considered as significant. RESULTS: In the study group all proportions were significantly less than the golden proportion. Ls-Rcus/Rch-Rcus and Ls-Lcus/Lch-Lcus had the least difference and Sn-Sm/N-Sn and Sn-Sm/Sm-Me had the most. In the control group, all proportions except Ls-Lcus/Lch-Lcus and Ls-Rcus/Rch-Rcus, were less than the golden proportion. Sn-Sm/N-Sn had the most difference and N-Sn/Sm-Me had the least.Approximately all proportions in cleft patients were significantly different from normal population. Ls-Lcus/Lch-Lcus had the highest difference between study and control group; however, Tr-Sn/Tr-Me in both groups were equal. CONCLUSIONS: The differences between facial indices in cleft lip and palate patients, normal people and golden proportion were significant. As facial proportions of normal people in the authors' study were also different from divine proportions, the authors can conclude that to reach acceptable esthetic results, the authors can approximate patients to normal populations. Unfortunately, the patients with large bone defects, cannot reach to the "esthetic" divine proportion even after reconstructive surgery.

Evaluating the Efficacy of a Modified Piezo-Puncture Method on the Rate of Tooth Movement in Orthodontic Patients: A Clinical Study.

OBJECTIVE: Owing to the increasing demand from orthodontic patients for a more rapid treatment, many studies have focused on accelerated tooth movement. Currently, one of the prevalent methods to achieve accelerated tooth movement is piezo-puncture. The aim of the present study was to evaluate the effect of a modified piezo-puncture method on tooth movement rate and type during canine retraction. METHODS: A total of 17 patients who required fixed orthodontic treatment with extraction of the maxillary first premolars were included in the study. Following a split-mouth design, upper canines were retracted with Ni-Ti coil spring that applied 150 g of force on each side (piezo-puncture on one side and contralateral side served as the control). Then, the rates of tooth movement, canine angulation and rotation, and anchorage loss were evaluated at T0 (before the intervention), T1 (1 month after the intervention), and T2 (2 months after the intervention). For calculating the canine movement rate, either the distance between the canine and the lateral incisor or the space between the second premolar and the canine was measured. In addition, pain perception was documented by Visual Analog Scale. Data were analyzed using the Kolmogorov-Smirnov normality test, Spearman correlation test, paired sample t-test, and Wilcoxon signed-rank test. RESULTS: No significant acceleration was observed in canine movement, canine tipping, rotation, or anchorage loss of molar in different times. CONCLUSION: Considering the limitations of the study, the application of piezo-puncture employing the protocol used in the present study failed to accelerate tooth movement and to decrease the unfavorable tipping, rotation, and molar anchorage loss.

Antimicrobial and physical properties of alginate impression material incorporated with silver nanoparticles.

BACKGROUND: Self-disinfecting impression materials would reduce time and energy needed for impression disinfecting process in clinic. The aim of this study was to evaluate the antimicrobial effect of alginate mixed with nanosilver solution at a concentration of 500 ppm and 1000 ppm on common oral microorganisms and assess changes in working time, setting time, and surface detail reproduction. MATERIALS AND METHODS: In this in vitro study, three groups were assigned. The first group was alginate, the second group was alginate mixed with 500 ppm nanosilver, and the third group was alginate mixed with 1000 ppm nanosilver. Antimicrobial effect on Escherichia coli, Staphylococcus aureus, and Candida albicans was studied using direct contact test in each group (n = 10). Working time (n = 10), setting time (n = 10), and surface detail reproduction (n = 10) were evaluated separately using the ISO 21563 protocol. Descriptive tables were used to describe the data. Kruskal-Wallis test used to determine significant differences in the number of colonies was counted in antimicrobial test (α = 0.05). RESULTS: No adverse effects observed in working time, setting time, and surface detail reproduction of alginate impressions. Alginate mixed with silver nanoparticles showed no inhibitory effect on S. aureus and C. albicans, but the number of E. coli colonies were counted in the group 1000 ppm was significantly lower than 500 ppm (P = 0.001). CONCLUSION: Antimicrobial effect of alginate mixed with silver nanoparticles is not clinically indicated. Nevertheless, its physical features did not change significantly.

Efficacy of Platelet-Rich Fibrin Combined with Autogenous Bone Graft in the Quality and Quantity of Maxillary Alveolar Cleft Reconstruction.

INTRODUCTION: The aim of this study was to evaluate the effect of platelet-rich fibrin (PRF) on the quality and quantity of bone formation in unilateral maxillary alveolar cleft reconstruction using cone beam computed tomography. MATERIALS AND METHODS: This study was conducted on 10 non-syndromic patients with unilateral cleft lip and palate within the age group of 9-12 years. The study population was randomly assigned into two groups of PRF and control, each of which entailed 5 cases. In the PRF group, the autogenous anterior iliac crest bone graft was used in combination with PRF gel. On the other hand, the control group was subjected to reconstruction only by bone graft. The dental cone beam CT images were obtained immediately (T0) and 3 months (T1) after the operation to assess the quality and quantity of the graft. Independent and paired sample t-tests and analysis of covariance were used to analyze and compare the data related to the height, thickness, and density of the new bone. RESULTS: The mean thickness difference of the graft in both PRF and control groups at T0 and T1 was not significantly different (P>0.05). Furthermore, the reduction changes of bone height at the graft site from T0 to T1 were not statistically significant for both groups (P=0.78). The mean total bone loss of the regenerated bone from T0 to T1 was lower in the control group than that in the PRF group; however, this difference was not statistically significant. CONCLUSION: The usage of PRF exerted no significant effect on the thickness, height, and density of maxillary alveolar graft.

Piezopuncture-Assisted Canine Distalization in Orthodontic Patients: Two Case Reports.

With the increasing number of young adults seeking orthodontic treatment to improve their smile esthetics or oral function, the time spent wearing brackets is one of the biggest challenges for these patients. Various surgical techniques have been developed over the years to accelerate tooth movement and reduce the total treatment time. A newly introduced, minimally invasive procedure namely piezopuncture, which uses a piezosurgical tool to create multiple cortical punctures through the gingiva, is presented in this report of two extraction cases.

Facial Anthropometric Evaluation of Unilateral Cleft Lip and Palate Patients: Infancy Through Adolescence.

INTRODUCTION: Craniofacial anthropometric studies measure the differences in humans' craniofacial dimensions. The aim of this study was to determine facial anthropometric dimensions of newborn to 12-year-old girls with nonsyndromic unilateral cleft lip and palate (UCLP). METHODS: In this cross-sectional analytical study, data was collected from 65 infant to 12-year old girls with UCLP. Digital frontal and profile facial photographs were transferred to a computer and desired anthropometric landmarks were traced on each image. Fifteen anthropometric parameters were measured which were the angles of facial, nasofacial, nasomental, Z, nasolabial, inclination of nasal base and labial fissure, nasal deviation, mentocervical, facial convexity and also ratios of nasal prominence relative to nasal height, middle to lower facial third, upper lip to lower lip height, columellar length relative to upper lip, and incisal show relative to incisal width. Pearson coefficient and linear regression were used for statistical analysis. RESULTS: Upper lip to lower lip height ratio and angles of nasofacial, nasolabial, and facial convexity decreased with the age of the patients. In contrast, nasomental angle and the ratios of columellar length to upper lip length, middle facial height to lower facial height, and incisal show relative to incisal width increased. Other parameters studied did not appear to have any significant correlation with age. CONCLUSION: In the girls with UCLP, various craniofacial dimensions have different growth rates with some parts growing slower than others. Some of the parameters studied were significantly correlated with age, thus growth-related curves and equations were obtained and presented.

Retentive Strength of Orthodontic Bands Cemented with Amorphous Calcium Phosphate-Modified Glass Ionomer Cement: An In-Vitro Study.

OBJECTIVES: The aim of this study was to evaluate and compare the retentive strength of orthodontic bands cemented with amorphous calcium phosphate (ACP)-containing and conventional glass ionomer cements (GICs). MATERIALS AND METHODS: One-hundred-and-twenty mandibular third molars were embedded in acrylic resin blocks with the buccal surface of crowns perpendicular to the base of the mold. The teeth were randomly divided into four groups containing 30 teeth each. Groups 1 and 3 were cemented using conventional GIC and groups 2 and 4 were cemented using ACP-containing orthodontic cement. Groups 1 and 2 without thermocycling, and groups 3 and 4 after thermocycling (5000 cycles, 5° to 55°C) were tested for retentive strength using a universal testing machine (crosshead speed of 1mm/minute). Two-way ANOVA was performed to compare the retentive strength of the groups. RESULTS: The highest retentive strength belonged to group 1, and it was significantly higher than that of group 2 (P<0.001) and group 3 (P=0.02). The mean strength for group 2 was significantly lower than that of group 1 (P<0.001) and group 4 (P=0.04). CONCLUSIONS: Although retentive strength decreased when ACP was added to GIC, the retentive strength of the samples cemented by ACP-containing GIC was remarkably high after thermocycling. It seems that in the oral cavity, ACP-containing GIC provides sufficient strength to endure forces applied on posterior teeth.

Comparison of esthetics perception and satisfaction of facial profile among male adolescents and adults with different profiles.

OBJECTIVE: To evaluate esthetics perception and satisfaction of the facial profile among Iranian male adolescents and adults. MATERIALS AND METHODS: In this cross-sectional study, male subjects referred to Orthodontic Department of Mashhad Dental School were enrolled (n = 84) and were divided into two groups: Adolescents (n = 39), and adults (n = 45). They were also assigned to straight, convex, or concave profile groups based on the facial profile angle (G-Sn-Pog'). An ideal silhouette of the lower facial profile was designed in Adobe® Photoshop® CS2 software (Kansas, USA). Then, eight other silhouettes representing different relations of the maxilla and mandible were constructed. Patients were asked to use numbers 1-10 to rank the facial profiles in the order of the attractiveness, and choose a silhouette that best closely resembled their own profile. Moreover, using a questionnaire patients were asked to rank their satisfaction with their profile, and asked to assign a number (1-5) to each question as follows; one represented the least satisfaction, while five reflected the highest satisfaction. RESULTS: Adult and adolescent subjects with straight (adults: 12.0 ± 1.9, adolescents: 12.8 ± 1.05) and concave (adults: 10.0 ± 2.14, adolescents: 10.0 ± 2.08) profile showed the highest and the least satisfaction with their own profile, respectively. Both adult and adolescent group selected "retrognathic maxilla, prognathic mandible" as the least attractive profile. Overall, "straight" and "bimaxillary dentoalveolar retrusion" were chosen as the most attractive silhouettes in adolescent and adults, respectively. In comparison to a professional opinion (clinician ranking), 42.9% of adolescents and 22% of adults were able to correctly diagnose their own profiles type. CONCLUSION: Most of the male adolescents and especially adults diagnosis of their own profile differed with a professional assessment.

Comparison of three different sterilization and disinfection methods on orthodontic markers.

BACKGROUND: Marking pencils which are frequently used in orthodontics may cause microbial contamination. The purpose of this study was to evaluate and compare the effectiveness of three disinfection and sterilization methods (autoclave, glutaraldehyde solution, and Deconex spray) on orthodontic markers. MATERIALS AND METHODS: One hundred and twenty orthodontic markers were divided into four groups each 30 pencils: One control group and three groups for three different disinfection/sterilization methods. To evaluate the effectiveness of these methods, pencils were initially contaminated by common pathogen by immersing the pencils in a suspension containing 1.5 × 10(8) CFU/ml organisms. Then, the pencils were subjected to corresponding disinfection/sterilization methods, and the number of remaining microorganisms was calculated and compared with control group. RESULTS: In the control group, the mean number of Escherichia coli was significantly higher than the other two microorganisms (P = 0.01, P = 0.031). However, the mean numbers of Staphylococcus aureus and Candida albicans were not significantly different (P = 0.1). After sterilization with autoclave and glutaraldehyde, no microbial growth was observed, whereas after disinfection with Deconx spray some colonies of microorganisms still could be observed. CONCLUSION: Autoclaving and glutaraldehyde solution are the best methods for disinfecting orthodontic markers.

Evaluation of the effects of three different mouthwashes on the force decay of orthodontic chains.

BACKGROUND: Elastomeric chains are commonly used in orthodontics. Force decay in these materials poses clinical problems. The aim of this study was to evaluate the effects of three different mouthwashes on the force decay of orthodontic chains. MATERIALS AND METHODS: In this experimental study, elastomeric chains with two different configurations were divided into eight groups (two control and six test groups). After 10 s of prestretching up to 100% of their initial length, the chains were stretched for 25 mm on jig pins and then immersed in artificial saliva, persica, chlorhexidine 0.2% and sodium fluoride 0.05% mouthwashes. Ten cycles of thermocycling between 5°C and 55°C were conducted daily during the test period. In order to reach a 200-g initial force, seven loop closed chains, and five-loop short chains were selected. Forces were recorded by digital force gauge (Lutron) at initial, 24 h, 1, 2, 3 and 4 weeks for all groups. The amount of force loss was compared among different mouthwashes and times using one-way analysis of variance (post-hoc, Tukey, α = 0.05). RESULTS: About 20% of the force decay occurred during the first 24 h, but after that and up to the 4(th) week the rate of force loss was gradual and steady. After 4 weeks, persica and chlorhexidine caused the lowest and the highest percentage of force loss, respectively. These two mouthwashes showed statistically significant differences at all points of time (P < 0.05). CONCLUSION: Within the limitations of this study, during the orthodontic treatment, persica is preferred to chlorhexidine for oral health control.

Ion release from orthodontic brackets in 3 mouthwashes: an in-vitro study.

INTRODUCTION: Stainless steel orthodontic brackets can release metal ions into the saliva. Fluoridated mouthwashes are often recommended to orthodontic patients to reduce the risk of white-spot lesions around their brackets. However, little information is available regarding the effect of different mouthwashes in ion release of orthodontic brackets. The purpose of this study was to measure the amount of metal ion release from orthodontic brackets when kept in different mouthwashes. METHODS: One hundred sixty stainless steel brackets (0.022-in, 3M Unitek, Monrovia, Calif) were divided randomly into 4 equal groups and immersed in Oral B (Procter & Gamble, Weybridge, United Kingdom), chlorhexidine (Shahdaru Labratories, Tehran, Iran), and Persica (Poursina Pharmaceutical Laboratories, Tehran, Iran) mouthwashes and distilled deionized water and incubated at 37°C for 45 days. Nickel, chromium, iron, copper, and manganese released from the orthodontic brackets were measured with an inductively coupled plasma spectrometer. For statistical analysis, 1-way analysis of variance (ANOVA) and the Duncan multiple-range tests were used. RESULTS: The results showed that ion release in deionized water was significantly (P <0.05) higher than in the 3 mouthwashes. Higher ion release was found with chlorhexidine compared with the other 2 mouthwashes. There was no significant difference (P >0.05) in nickel, chromium, iron, and copper ion release in the Oral B and Persica mouthwashes. The level of manganese release was significantly different in all 4 groups. CONCLUSIONS: If ion release is a concern, Oral B and Persica mouthwashes might be better options than chlorhexidine for orthodontic patients with stainless steel brackets.