Effect of continuous vs sequential chelation on the mechanical properties of root dentin: An ex vivo study.

OBJECTIVES: To evaluate the mechanical properties of root canal dentin treated with sodium hypochlorite (NaOCl) in combination with hydroxyethylidene diphosphonic acid (HEDP) or ethylenediaminetetraacetic acid (EDTA). METHODS: For testing fracture resistance, 45 single-rooted teeth were instrumented and irrigated with NaOCl/HEDP, NaOCl/EDTA, or distilled water. Fifteen untreated teeth served as control. After obturation, specimens from the experimental groups were thermocycled, dynamically-loaded, and then statically-loaded in a universal testing machine until failure. For flexural strength analysis, 15 teeth were instrumented and irrigated with NaOCl/HEDP or NaOCl/EDTA. Root segments were sectioned into dentin bars and tested for flexural strength using a universal testing machine. For microhardness evaluation, 20 teeth were instrumented and irrigated with NaOCl/HEDP or NaOCl/EDTA. Dentin disks from the coronal-third of each root segment were prepared, one before and one after irrigation, for microhardness testing with a Knoop hardness tester. RESULTS: The highest fracture resistance was recorded in the untreated group, and the lowest in the EDTA group. Although the HEDP group had higher fracture resistance than the EDTA group, the distilled water group demonstrated even greater fracture resistance than the HEDP group. Specimens treated with HEDP had significantly higher flexural strength and microhardness values when compared with those treated with EDTA. CONCLUSION: The fracture resistance, flexural strength, and microhardness of root canal dentin were higher when root canals were irrigated with NaOCl/HEDP, when compared with NaOCl/EDTA. CLINICAL SIGNIFICANCE: Irrigating root canals with NaOCl combined with HEDP significantly improves the mechanical integrity of root canal dentin compared to the use of NaOCl with EDTA.

Quantifying health utilities of young adult orthodontic patients using the time trade-off method: a cross-sectional study.

OBJECTIVE: To study the feasibility of time trade-off (TTO) method in quantifying health utility ratings in different types of malocclusion. MATERIAL AND METHODS: In this cross-sectional study, 70 orthodontic patients aged 18 years or above, reporting for treatment/consultation, were included and interviewed. Malocclusion-related health utilities were assessed through the TTO method, and oral health-related quality of life was measured with the help of Orthognathic Quality of Life Questionnaire (OQLQ). Angle's classification of malocclusion was recorded. Bivariate analyses and multivariate Poisson's regression were done to find out an association between the oral health utility values, OQLQ and demographic and clinical characteristics. RESULTS: Patients with skeletal Class III malocclusion had lower health utility values than those with Class I and Class II malocclusions (p=0.013). Poisson's regression showed that Angle's Class II division 1 (0.90, CI 0.84 to 0.97), Class III (0.68, CI 0.59 to 0.95) and Skeletal malocclusion (0.79, CI 0.71 to 0.87) and OQLQ scores (1.0, CI 1 to 1.003) were found to be significant predictors of TTO utility scores. CONCLUSIONS: TTO utilities were found to be valid and well correlated with clinical findings. Health utilities could serve as useful and reliable markers of health-related quality of life (HRQL) among individuals or communities and help cost-effective preventive or intervention programs planning.

Effect of Real-Time Environment on Mechanical Properties of Preformed Stainless Steel Archwires: An In Vivo Study.

Introduction: Clinicians should be aware of any effect the oral environment may have on archwires. Laboratory models fail to closely imitate intraoral conditions. The aim was to evaluate the change in mechanical properties of preformed stainless steel archwires after 15 weeks of exposure to the oral environment. Methods: Three commercially manufactured 0.019 × 0.025″ stainless steel archwires were evaluated. Young's modulus, yield strength, spring factor, and hardness were studied. The unexposed distal end cuts (control samples) and archwires were tested after 15 weeks of intraoral exposure (test samples). Tension tests, Vickers microhardness tests, and nanoindentation tests were carried out. Results: Normality was tested using the Shapiro-Wilk test. Statistical analyses included the paired t-test for intragroup comparisons and Kruskal-Wallis ANOVA with the post hoc Dunn test for comparison of mean percentage reduction in values. At T15, Young's modulus showed a statistically significant decrease. Changes in yield strength and spring factor were not significant for groups other than American Orthodontics wires. The reduction in hardness was significant in 3M Unitek. Vickers, tension, and nanoindentation tests demonstrated an expansive range between hardness and Young's modulus so determined. Conclusion: 3M Unitek archwires showed the highest difference in Young's modulus. Yield strength values increased in Ortho Organizers archwires. Spring factor decreased only in 3M Unitek archwires. Hardness values obtained from various tests did not produce identical results.

Quantifying health utilities of young adult orthodontic patients using the time trade-off method: a cross-sectional study

ABSTRACT Objective: To study the feasibility of time trade-off (TTO) method in quantifying health utility ratings in different types of malocclusion. Material and Methods: In this cross-sectional study, 70 orthodontic patients aged 18 years or above, reporting for treatment/consultation, were included and interviewed. Malocclusion-related health utilities were assessed through the TTO method, and oral health-related quality of life was measured with the help of Orthognathic Quality of Life Questionnaire (OQLQ). Angle's classification of malocclusion was recorded. Bivariate analyses and multivariate Poisson's regression were done to find out an association between the oral health utility values, OQLQ and demographic and clinical characteristics. Results: Patients with skeletal Class III malocclusion had lower health utility values than those with Class I and Class II malocclusions (p=0.013). Poisson's regression showed that Angle's Class II division 1 (0.90, CI 0.84 to 0.97), Class III (0.68, CI 0.59 to 0.95) and Skeletal malocclusion (0.79, CI 0.71 to 0.87) and OQLQ scores (1.0, CI 1 to 1.003) were found to be significant predictors of TTO utility scores. Conclusions: TTO utilities were found to be valid and well correlated with clinical findings. Health utilities could serve as useful and reliable markers of health-related quality of life (HRQL) among individuals or communities and help cost-effective preventive or intervention programs planning.

RESUMO Objetivo: Estudar a viabilidade do método Time trade-off (TTO) para quantificar escores de valoração da saúde em diferentes tipos de má oclusão. Material e Métodos: Neste estudo transversal, foram incluídos e entrevistados 70 pacientes ortodônticos com idade igual ou superior a 18 anos, que compareceram para tratamento/consulta. A valoração da saúde em relação à má oclusão foi avaliada por meio do método TTO e a qualidade de vida relacionada à saúde bucal foi medida com a ajuda do Questionário de Qualidade de Vida Ortognática (Orthognathic Quality of Life Questionnaire, OQLQ). A classificação da má oclusão segundo Angle foi registrada, e análises bivariadas e regressão multivariada de Poisson foram feitas para verificar qualquer associação entre os escores de valoração da saúde bucal, OQLQ e características demográficas e clínicas. Resultados: Os pacientes com má oclusão esquelética de Classe III apresentaram escores de valoração da saúde mais baixos do que aqueles com má oclusão de Classe I e Classe II (p=0,013). A regressão de Poisson mostrou que a Classe II de Angle divisão 1 (0,90, IC 0,84 a 0,97), Classe III (0,68, IC 0,59 a 0,95), má oclusão esquelética (0,79, IC 0,71 a 0,87) e os escores do OQLQ (1,0, IC 1 a 1,003) foram considerados preditores significativos dos escores de valoração pelo método TTO. Conclusões: Os escores do TTO foram considerados válidos e bem correlacionados com os achados clínicos, e podem servir como marcadores úteis e confiáveis da qualidade de vida relacionada à saúde (health-related quality of life, HRQL) entre indivíduos ou comunidades, e ajudar no planejamento de programas de prevenção ou de intervenção, com uma boa relação custo-benefício.

Fluorescence and Photoacoustic Spectroscopy-Based Assessment of Mitochondrial Dysfunction in Oral Cancer Together with Machine Learning: A Pilot Study.

The current study reports an integrated approach of machine learning and tryptophan fluorescence and photoacoustic spectral properties to assess the mitochondrial status under oral pathological conditions. The mitochondria in the study were isolated from oral cancer tissues and adjacent normal counterparts, and the corresponding fluorescence and photoacoustic spectra of tryptophan were recorded at 281 nm pulsed laser excitations. A set of features were selected from the pre-processed spectra and were used to classify the data using support vector machine (SVM) learning in the MATLAB platform. SVM analysis demonstrated clear differentiation between mitochondria isolated from normal and cancer tissues for fluorescence (sensitivity, 86.6%; specificity, 90%) and photoacoustic (sensitivity, 86.6%; specificity, 96.6%) measurements. Further investigation into the influence of change in protein conformation on the nature of tryptophan spectral properties was evaluated by 8-anilino-1-naphthalene sulfonic acid (ANS) fluorescence assay. The impact of protein structural changes on the mitochondrial functions was also estimated by mitochondrial membrane potential (MMP), reactive oxygen species (ROS), and cytochrome c oxidase (COX) assays, suggesting an altered mitochondrial function. The findings indicate that tryptophan fluorescence and photoacoustic spectral properties together with machine learning algorithms may delineate the mitochondrial functional status in vitro, indicating its translational potential.

Lip profile changes in patients with Class II Division 1 malocclusion of varied growth patterns treated with maxillary premolar extractions: A pilot study.

INTRODUCTION: This retrospective pilot study assessed the pre- and posttreatment lip profile changes among adult patients with Class II Division 1 malocclusion of varied growth patterns and compared these changes with patients with a skeletal Class I relationship, to identify the dental, skeletal, and soft tissue cephalometric variables that altered the posttreatment lip profile. METHODS: A total of 33 digital cephalograms were divided into 4 study groups based on the mandibular plane (Mp-SN) angle: group 1 (control, skeletal Class I; mean angle = 21.5°) (n = 8), group 2 (Class II Division 1 malocclusion; low angle = <26°) (n = 8), group 3 (Class II Division 1 malocclusion; intermediate angle = 26°-38°) (n = 9), and group 4 (Class II Division 1 malocclusion; high angle = >38°) (n = 8). RESULTS: We observed a significant decrease in SNA, ANB, maxillary incisor to NA (degrees and millimeters), and soft tissue parameters, especially lip strain and lower lip to E line and upper lip to E line. Posttreatment intergroup comparison showed a significant increase of Mp-SN, and this increase was greater in group 3, followed by group 4 as compared with group 1. In addition, statistically significant differences in SNA, ANB, mandibular incisor to NB (degrees) and IMPA, and H angle in groups 2-4 were observed. CONCLUSIONS: Patients with Class II Division 1 malocclusion showed a significant decrease in SNA, ANB, maxillary incisor to NA, and all soft tissue parameters in posttreatment compared with group 1. Thus, the soft tissue changes resulted in a similar profile to patients in group 1, who are considered to have an aesthetically pleasing posttreatment profile.

Validation of an Indian (Kannada) translation of the Family Impact Scale questionnaire and the impact of malocclusion on the families of adolescent school children.

OBJECTIVES: The objectives of this study were to validate an Indian translation of the Family Impact Scale (FIS) questionnaire and assess the impact of malocclusion on the families of adolescent school children between 12 and 15 years old across socio-economic strata (SES). MATERIALS AND METHODS: The sample consisted of 768 school children aged between 12 and 15 years from randomly selected schools in Udupi district. The FIS and informed consent forms were sent through the children to be completed by their parents. Information was collected on socio-demographic details, past dental visit in the last year, type of school and SES. Clinical examination for malocclusion using the Dental Aesthetic Index was conducted by a single trained and calibrated examiner. RESULTS: The prevalence of malocclusion was 59.9%. The intra-class correlation for the total FIS score of 0.95 and Cronbach's alpha value of 0.88 demonstrated internal consistency. There was a significant difference in the overall and subscale scores of FIS between parents of children with and without malocclusion (P < 0.001). Parents of children who had malocclusion had significantly higher FIS scores across all SES (P < 0.001). Parents of children with malocclusion had 1.86 (P < 0.001, 95% CI = 1.60-2.17) times higher FIS scores than parents of children without malocclusion after adjusting for age, gender, SES, and past dental visits in the last year. CONCLUSION: The psychometric properties of the FIS were found satisfactory for assessing the effect of a child's oral condition on his/her family. Malocclusion in children had a significant negative influence on the family impact scores.

Anti-plaque and anti-gingivitis effect of Papain, Bromelain, Miswak and Neem containing dentifrice: A randomized controlled trial.

BACKGROUND: Patients undergoing fixed orthodontic therapy may have difficulty in maintaining a good oral hygiene due to the difficulty posed by the appliances in accessing such areas. This study aimed to compare anti-plaque and anti-gingivitis efficacy of dentifrice containing Papain, Bromelain, Miswak and Neem with a standard dentifrice among patient's undergoing fixed orthodontic treatment. MATERIAL AND METHODS: Single center, single blind, parallel arm, randomized controlled clinical trial with an allocation ratio of 1:1 was conducted. Evaluation of plaque and gingivitis was done using Williams modification of Silness and Loe Plaque Index (PI) for use in orthodontic subjects and Loe and Silness's Gingival Index (GI) at baseline and one month. RESULTS: Inter-group comparison showed there was significantly lower mean plaque index in test (0.88 ±0.05) than in control group (1.17 ±0.05) after adjusting for the baseline plaque index (p<0.001). Similarly, there was significantly lower mean gingival index in test (0.87 ±0.04) than in control group (1.14 ±0.04) after adjusting for the baseline gingival index (p<0.001). CONCLUSIONS: The efficacy of the test dentifrice in limiting plaque and gingivitis suggests that it can be used as a home based adjunct to clinical therapy in orthodontic patients. Key words:Bromelain, gingivitis, miswak, neem, papain, plaque.

Effect of Aloe vera, chlorine dioxide, and chlorhexidine mouth rinses on plaque and gingivitis: A randomized controlled trial.

OBJECTIVE: To evaluate the effect of Aloe vera, chlorine dioxide, and chlorhexidine mouth rinses on plaque and gingivitis in orthodontic treatment. MATERIALS AND METHODS: A randomized single-center, single-blind, parallel group, controlled trial was conducted among 90 subjects undergoing fixed orthodontic treatment. The subjects were randomly divided into one of the three study groups (Aloe vera, chlorhexidine, chlorine dioxide). Plaque and gingivitis were assessed using modified Silness and Loe Plaque Index and Gingival Index at baseline and at follow-up after 15 days. Paired t-test and ANOVA with post hoc Dunnett test were used. A p-value of <0.05 was considered statistically significant. RESULTS: A total of 85 participants completed the study; among them, 40 were male and 45 were female. There was significant reduction in mean plaque and gingival scores in all the 3 groups at follow-up when compared to baseline. A significantly higher reduction (plaque and gingival scores) was found in chlorhexidine when compared with the Aloe vera group. However, no significant difference was seen between chlorhexidine and chlorine dioxide with respect to mean reduction in plaque and gingival scores. CONCLUSION: Chlorine dioxide can be a suitable and economical alternative for chlorhexidine. Further long-term studies are recommended for evaluating their effectiveness.

Unusual intraosseous transmigration of impacted tooth.

Transmigration of an impacted tooth through the symphyseal suture is a rare and special developmental anomaly of unknown etiology that is unique to the mandibular canine. Maxillary canine transmigration is even rarer. Transmigrated canines are particularly significant due to the aesthetic and functional importance. A maxillary lateral incisor crossing the mid-palatal suture has never been reported in the literature. The aim of this report is to present the first case of simultaneous transmigration of a lateral incisor and canine in the maxilla. The paper also reports four unusual cases of unilateral canine transmigration in the maxilla and mandible and successful eruption of one of the transmigrated mandibular canines following orthodontic traction. Etiology of transmigration and its clinical considerations are also discussed.