Clinical evaluation of Artificial Intelligence Driven Remote Monitoring technology for assessment of patient oral hygiene during orthodontic treatment.

INTRODUCTION: This study aimed to clinically evaluate the accuracy of Dental Monitoring's (DM) artificial intelligence (AI) image analysis and oral hygiene notification algorithm in identifying oral hygiene and mucogingival conditions. METHODS: Twenty-four patients seeking orthodontic therapy were monitored by DM oral hygiene protocol during their orthodontic treatment. During the bonding appointment and at each of 10 subsequent adjustment visits, a total of 232 clinical oral examinations were performed to assess the presence of the 3 oral hygiene parameters that DM monitors. In each clinical timepoint, the subjects took an oral DM scan and received a notification regarding their current oral status at that moment in time. Sensitivity, specificity, positive predictive value, and negative predictive value were calculated to evaluate AI and clinical assessment of plaque, gingivitis, and recession. RESULTS: A total of 232 clinical time points have been evaluated clinically and by the DM AI algorithm. For DM's AI detection of plaque and calculus, gingivitis, and recession, the sensitivity was 0.53, 0.35, and 0.22; the specificity was 0.94, 0.96, and 0.99; and the accuracy was 0.60, 0.49, and 0.72, respectively. CONCLUSIONS: DM's oral hygiene notification algorithm has low sensitivity, high specificity, and moderate accuracy. This indicates a tendency of DM to underreport the presence of plaque, gingivitis, and recession.

Comparison of light transmittance and color changes between polyurethane and copolyester retainer materials after staining and destaining.

BACKGROUND: Retainers are the only effective approach to prevent orthodontic relapse. The aim of this study was to compare the changes in color and light-transmittance of rough and smooth thermoformed polyurethane and copolymer retainer samples after staining in different solutions and destaining with different approaches. METHODS: Four hundred copolyester (Essix® ACE) and 400 polyurethane (Zendura®) samples with different surface textures, smooth and rough, were stained in 4 different solutions (n = 100 per solution) over 28 days. Each of the four groups of 100 stained samples of each material was subdivided into 5 groups of 20 samples and subjected to different destaining solutions. Light transmittance and color changes were evaluated using a spectrometer and a spectrophotometer. Mean differences were compared using a two-way analysis of variance (ANOVA) and posthoc multiple comparison tests at P = 0.05. RESULTS: No significant differences in light transmittance were found between both untreated materials. Both materials were stained in a similar fashion and showed no significant differences between two materials after staining. Coffee and tea stained both materials more significantly than wine, but there was a significant difference of changes of color and light transmittance between rough and smooth surfaces during the destaining in coffee- and tea-stained samples of copolyester material. All destaining solutions were effective at removing all stains on the samples. The surface roughness of the material plays a significant role in the ability of the materials to be destained, demonstrating a more significant greater effect on cleaning rough samples for improvements in light-transmittance and greater changes in color. CONCLUSIONS: This study concluded that the surface of materials plays a significant role in the material destaining and staining. In addition, the different polymers used for retainer fabrication exhibited different responses during the destaining process depending on types of stains.

Effectiveness of AI-driven remote monitoring technology in improving oral hygiene during orthodontic treatment.

OBJECTIVE: This study aimed to evaluate the effectiveness of Dental Monitoring™ (DM™) Artificial Intelligence Driven Remote Monitoring Technology (AIDRM) technology in improving the patient's oral hygiene during orthodontic treatment through AI-based personalized active notifications. METHODS: A prospective clinical study was conducted on two groups of orthodontic patients. DM Group: (n = 24) monitored by DM weekly scans and received personalized notifications on the DM smartphone application regarding their oral hygiene status. Control Group (n = 25) not monitored by DM. Both groups were clinically assessed using Plaque Index (OPI) and the Modified Gingival Index (MGI). DM Group was followed for 13 months and the Control Group was followed for 5 months. Student-independent t test and paired t tests were used to investigate the mean differences between study groups and between time points for each group respectively. RESULTS: At all time points, the mean differences indicated that the DM group had lower OPI and MGI values than the control group. The mean value for OPI and MGI were statistically significantly lower in the DM group (OPI = 1.96, MGI = 1.56) than in the control group (OPI = 2.41, MGI = 2.17) after 5 months. A rapid increase in mean OPI and MGI values was found between T0 and T1 for both study groups. A plateau effect for OPI scores appeared to occur from T1 to T5 for both study groups, but the plateau effect seemed to be more pronounced for the DM group than the study group. The MGI values for both study groups also increased dramatically from baseline to T5, however, a plateau effect was not observed. CONCLUSIONS: The oral hygiene of orthodontic patients rapidly worsens over the first 3 months and plateaus after about 5 months of treatment. AIDRM by weekly DM scans and personalized active notifications may improve oral hygiene over time in orthodontic patients.

Evaluation of upper airway characteristics in patients with and without sleep apnea using cone-beam computed tomography and computational fluid dynamics.

OBJECTIVE: To determine if upper airway characteristics and airway pressure change significantly between low risk, healthy non-OSA subjects, and OSA subjects during respiration using cone-beam computed tomography (CBCT) imaging and steady-state k-ω model computational fluid dynamics (CFD) fluid flow simulations, respectively. MATERIALS AND METHODS: CBCT scans were collected at both end-inhalation and end-exhalation for 16 low-risk non-OSA subjects and compared to existing CBCT data from 7 OSA subjects. The CBCT images were imported into Dolphin Imaging and the upper airway was segmented into stereolithography (STL) files for area and volumetric measurements. Subject models that met pre-processing criteria underwent CFD simulations using ANSYS Fluent Meshing (Canonsburg, PA) in which unstructured mesh models were generated to solve the standard dual equation turbulence model (k-ω). Objective and supplemental descriptive measures were obtained and statistical analyses were performed with both parametric and non-parametric tests to evaluate statistical significance at P < .05. RESULTS: Regarding area and volumetric assessments, there were statistically significant mean differences in Total Volume and Minimum CSA between non-OSA and OSA groups at inhalation and exhalation (P = .002, .003, .004, and .007), respectively. There were also statistically significant mean differences in volume and min CSA between the inhalation and exhalation for the non-OSA group (P < .001 and .002), respectively. CONCLUSION: While analysis of the CFD simulation was limited by the collected data available, a finding consistent with published literature was that the OSA subject group simulation models depicted the point of lowest pressure coinciding with the area of maximum constriction.

Cone-beam computed tomography assessment of maxillary anterior alveolar bone remodelling in extraction and non-extraction orthodontic cases using stable extra-alveolar reference.

OBJECTIVE: To explore alveolar cortical positional change in response to tooth movement in extraction and non-extraction orthodontic cases, using cone-beam computed tomography (CBCT) and stable extra-alveolar references. MATERIALS AND METHODS: The pre-treatment (T1) and post-treatment (T2) CBCT scans of 25 extraction (EXT) and matched 25 non-extraction (Non-EXT) orthodontic cases were imported into Dolphin Imaging 3D, and oriented uniformly. Sagittal and axial CBCT cross-sections were traced using customized software-generated guides. The displacement of teeth and alveolar bone cortices were automatically measured using the palatal plane (PP) and the line perpendicular to PP and passing Sella as reference. Intra- and inter-group differences between T1 and T2 were analysed. Subjects were also superimposed three-dimensionally using Geomagic Control X for qualitative analysis of cortical remodelling. RESULTS: The EXT group showed incisor retraction, while the Non-EXT group exhibited statistically significant incisor anterior tipping (P < .05). In EXT, both the labial and palatal cortices are resorbed. Non-EXT showed labial cortex anterior modelling, and statistically significant palatal cortex resorption (P < .05). In both groups, statistically significant decrease in total and palatal alveolar widths, increase in labial widths, and palatal dehiscence were observed. Comparatively, EXT showed significantly more incisal total and palatal width decrease and palatal vertical bone loss. CONCLUSION: Labial cortical remodelling was shown to follow anterior tooth movement, but the palatal cortical response to incisor retraction and labial cortical remodelling in general remained inconclusive. Narrowing of the alveolar housing and palatal dehiscence were observed regardless of extraction following orthodontic treatment.

Novel Machine Learning Algorithms for Prediction of Treatment Decisions in Adult Patients With Class III Malocclusion.

BACKGROUND: Management of Class III (Cl III) dentoskeletal phenotype is often expert-driven. PURPOSE: The aim is to identify critical morphological features in postcircumpubertal Cl III treatment and appraise the predictive ability of innovative machine learning (ML) algorithms for adult Cl III malocclusion treatment planning. STUDY DESIGN: The Orthodontics Department at the University of Illinois Chicago undertook a retrospective cross-sectional study analyzing Cl III malocclusion cases (2003-2020) through dental records and pretreatment lateral cephalograms. PREDICTOR: Forty features were identified through a literature review and gathered from pretreatment records, serving as ML model inputs. Eight ML models were trained to predict the best treatment for adult Cl III malocclusion. OUTCOME VARIABLE: Predictive accuracy, sensitivity, and specificity of the models, along with the highest-contributing features, were evaluated for performance assessment. COVARIATES: Demographic covariates, including age, gender, race, and ethnicity, were assessed. Inclusion criteria targeted patients with cervical vertebral maturation stage 4 or above. Operative covariates such as tooth extraction and types of orthognathic surgical maneuvers were also analyzed. ANALYSES: Demographic characteristics of the camouflage and surgical study groups were described statistically. Shapiro-Wilk Normality test was employed to check data distribution. Differences in means between groups were evaluated using parametric and nonparametric independent sample tests, with statistical significance set at <0.05. RESULTS: The study involved 182 participants; 65 underwent camouflage mechanotherapy, and 117 received orthognathic surgery. No statistical differences were found in demographic characteristics between the two groups (P > .05). Extreme values of pretreatment parameters suggested a surgical approach. Artificial neural network algorithms predicted treatment approach with 91% accuracy, while the Extreme Gradient Boosting model achieved 93% accuracy after recursive feature elimination optimization. The Extreme Gradient Boosting model highlighted Wit's appraisal, anterior overjet, and Mx/Md ratio as key predictors. CONCLUSIONS: The research identified significant cephalometric differences between Cl III adults requiring orthodontic camouflage or surgery. A 93% accurate artificial intelligence model was formulated based on these insights, highlighting the potential role of artificial intelligence and ML as adjunct tools in orthodontic diagnosis and treatment planning. This may assist in minimizing clinician subjectivity in borderline cases.

In-vivo evaluation of Artificial Intelligence Driven Remote Monitoring technology for tracking tooth movement and reconstruction of 3-dimensional digital models during orthodontic treatment.

INTRODUCTION: An in-vivo evaluation of the Dental Monitoring (DM; Paris, France) Artificial Intelligence Driven Remote Monitoring technology was conducted in an active clinical setting. Our objectives were to compare the accuracy and validity of the 3-dimensional (3D) digital models remotely generated from the DM application to 3D Digital Models generated from the iTero Element 5D intraoral scanner (Align Technologies, San Jose, Calif) of patients' dentition during in-vivo fixed orthodontic treatment. METHODS: The orthodontic treatment of 24 patients (aged 14-55 years) was tracked across an average of 13.4 months. Scans of the maxillary and mandibular arches of each patient were taken by an iTero intraoral scanner and with the DM application before treatment initiation without (T0) and with (T1) the fixed orthodontic appliances and at every in-person adjustment appointment (T2-T10). The global deviation between the reconstructed digital models from the DM and iTero scans was compared at each time point using Geomagic Control-X 2020 (3D Systems, Rock Hill, SC). Descriptive analysis was conducted to determine the mean deviation at each time point for the maxillary and mandibular arches, to compare the maxilla and mandible mean deviations at each time point to the null hypothesis mean of 0 mm and the paired mean of the average at each time point between the maxilla and mandible. RESULTS: The findings revealed no clinically significant difference between the reconstructed digital models generated by the iTero IOS and the remotely reconstructed digital dental models generated by the DM application. CONCLUSION: DM artificial intelligence tracking algorithm can track tooth movement and reconstruct 3D digital models to a clinically acceptable degree for orthodontic application.

COVID-19 infection rates and mitigation strategies in orthodontic practices.

BACKGROUND: COVID-19 has impacted and increased risks for all populations, including orthodontic patients and providers. It also changes the practice management and infection control landscape in the practices. This study aimed to investigate the COVID-19 infection and vaccination status of orthodontic providers and mitigation approaches in orthodontic practices in the United States during 2021. METHODS: A validated 50-question research electronic data capture (REDCap) browser-based questionnaire was distributed to 12,393 orthodontists and pediatric dentists who reported actively providing orthodontic treatment. Questions were designed to collect demographic data of respondents, evaluate the COVID-19 mitigation approaches, and evaluate the history of COVID-19 infection and vaccination status of the orthodontic providers. Associations of demographic and the COVID-19 mitigation approaches were assessed using chi-square tests at the significance level of 0.05. RESULTS: Four hundred fifty-seven returned the survey (response rate 3.69%) for analysis. Most respondents were vaccinated, and increased infection control measures in response to the pandemic. Half of the respondents practiced teledentistry and switched to digital impression systems. Two-thirds reported difficulties in attaining PPEs due to the increased cost and scarcity of PPEs. About 6% of respondents reported a history of COVID-19 infection, and 68.9% of their staff had COVID-19 infection. Statistically significant associations were found between increased practice experience with difficulties in acquiring PPE (p = .010). There were no significant associations between races of respondents, geographic location, and years of practicing when cross-tabulated with vaccination status or COVID-19 infection rate (p > .05). CONCLUSION: Increased infection control strategies were employed in almost all orthodontic practices in addition to existing universal precaution. Most of the orthodontic providers and their staff members were vaccinated. While staff's infection rates were an issue, doctors' infection rates remained low.

The use of teleorthodontics during the COVID-19 pandemic and beyond - perspectives of patients and providers.

BACKGROUND: The COVID-19 pandemic significantly impacted dental services, resulting in reduced staff availability, limited appointments, and some dental clinics even being forced to close their doors. Despite these challenges, the need for dental consultants remained present, particularly in emergency situations. One area of orthodontics that had seen a surge in demand during the pandemic is Teleorthodontics. With the help of Teleorthodontics, orthodontic consultations, assessments, and even treatment monitoring could be conducted remotely, making it a safe and convenient option for patients during those challenging times. AIM: This survey aimed to evaluate the acceptance of patients and their orthodontists on the use of different modes of communication through Teleorthodontics during the COVID-19 pandemic and their willingness to continue using this in the future. METHODS: An online survey instrument in Qualtrics was distributed to orthodontic patients at the University of Illinois, Chicago. The survey was available on a rolling basis for up to 6 months. A total number of 364 partients voluntarily participated in the survey. The Faculty and Residents were also asked to participate in a survey through recruitment via their UIC email addresses. RESULTS: According to our survey, both patients and providers showed acceptance of Teleorthodontics and have used it in different forms during orthodontic treatment. The application is easy-to-use, convenient, and not at all time-consuming. Overall satisfaction with using this application was recorded at 92%, with 66% of patients stating that it saved them time by eliminating the need to travel to the orthodontic clinic. 30% of providers found that the interaction with patients using Teleorthodontics was a positive experience and would recommend it in future. CONCLUSION: Teleorthodontics has shown great potential, particularly in follow-up cases, and holds promise as a valuable tool for online remote dental consultations in the future.

Bimaxillary transverse constriction in adults: Short-term follow-up of non-surgical arch expansion.

OBJECTIVE: Concurrent maxillary and mandibular expansion is a treatment option for patients with maxillary and mandibular transverse constriction. These patients do not present with crossbite but require expansion due to narrow arches and associated crowding, dark buccal corridors and decreased anterior arch contour. The objective of the study is to first establish Bimaxillary Transverse Constriction as an under-recognized malocclusion and second to evaluate whether in adults the maxillary and mandibular arches can be successfully and safely expanded. SETTING AND SAMPLE POPULATION: Pre- and post-treatment study models and lateral cephalograms of 31 adults with Bimaxillary Transverse Constriction expanded non-surgically were analysed. Thirty adult orthodontic patients who did not require expansion served as a control. Expanders were turned no more frequently than every other day in the maxilla and every third day in the mandible. MATERIALS AND METHODS: Measurements in both arches made on OrthoCAD models were transarch widths, molar and premolar axial angulation, clinical crown height of posterior teeth and cuspids, and mandibular divergence. Retrospective comparison of the 2 groups used independent Student's t tests for mean differences between groups. RESULTS: At pre-treatment, the expansion group demonstrated significant transverse constriction compared with the control. Increased widths were achieved in the expansion group (4 mm in the maxilla and 2.5 mm in the mandible), while the control group was unchanged. The mandibular plane was unchanged. There was no buccal attachment loss. CONCLUSION: Non-surgical expansion in the maxilla and mandible is a viable treatment option for adult patients with Bimaxillary Transverse Constriction.

Accuracy of Dental Monitoring 3D digital dental models using photograph and video mode.

INTRODUCTION: This study aimed to test the accuracy of the 3-dimensional (3D) digital dental models generated by the Dental Monitoring (DM) smartphone application in both photograph and video modes over successive DM examinations in comparison with 3D digital dental models generated by the iTero Element intraoral scanner. METHODS: Ten typodonts with setups of class I malocclusion and comparable severity of anterior crowding were used in the study. iTero Element scans along with DM examination in photograph and video modes were performed before tooth movement and after each set of 10 Invisalign aligners for each typodont. Stereolithography (STL) files generated from the DM examinations in photograph and video modes were superimposed with the STL files from the iTero scans using GOM Inspect software to determine the accuracy of both photograph and video modes of DM technology. RESULTS: No clinically significant differences, according to the American Board of Orthodontics-determined standards, were found. Mean global deviations for the maxillary arch ranged from 0.00149 to 0.02756 mm in photograph mode and from 0.0148 to 0.0256 mm in video mode. Mean global deviations for the mandibular arch ranged from 0.0164 to 0.0275 mm in photograph mode and from 0.0150 to 0.0264 mm in video mode. Statistically significant differences were found between the 3D models generated by the iTero and the DM application in photograph and video modes over successive DM examinations. CONCLUSIONS: 3D digital dental models generated by the DM smartphone application in photograph and video modes are accurate enough to be used for clinical applications.

Racial and sex differences in timing of the cervical vertebrae maturation stages.

INTRODUCTION: Our objective was to investigate skeletal maturation of female and male subjects from different racial groups by comparing the cervical vertebrae maturation (CVM) stages. METHODS: The study included 3 racial groups: white, African American, and Hispanic subjects. Each group was subdivided into female and male. The age range of the subjects was between 7 and 18 years. The sample included 60 lateral cephalographs for each subgroup. Skeletal maturation of the cervical vertebrae was assessed according to a method that described 6 CVM stages. RESULTS: Racial differences were evident in the mean ages of CVM stages 2, 3, 4, and 5 (P = 0.002; P = 0.003; P = 0.001; and P = 0.001, respectively) among females; among males, only stage 3 was different (P = 0.001). Sex differences in the mean ages of stages 1, 2, and 3 in Hispanic subjects (P <0.001), and in stages 2 and 3 in African American subjects (P = 0.019 and P <0.001) and white subjects (P = 0.004 and P <0.001) were detected. CONCLUSIONS: In both sexes, racial differences were not apparent between whites and African Americans, but differences were evident between Hispanics vs both whites and African Americans. Sex differences were apparent between the sexes in each of the 3 ethnic groups in CVM stages 2 and 3. No sex differences were detected in stages 4, 5, or 6 in any of the 3 racial groups. It is recommended to consider racial and sex differences when using the CVM stage as a skeletal maturation indicator.

Effects of unilateral premolar extraction treatment on the dental arch forms of Class II subdivision malocclusions.

INTRODUCTION: A retrospective study evaluating posttreatment symmetry in dental arch form and midlines was carried out in Class II subdivision patients treated with unilateral and bilateral maxillary premolar extractions. METHODS: Using Geomagic (version 14; Geomagic, Research Triangle Park, NC) and MATLAB (version 8.4; MathWorks, Natick, Mass) software, best-fit curves expressed as quartic polynomials were generated for 13 Class II subdivisions treated with unilateral extractions and 20 treated with bilateral maxillary premolar extractions. Transverse and sagittal measurements were recorded to assess symmetry. Dental models were superimposed on constructed reference planes to generate average posttreatment arches. Statistical comparisons were performed with the significance level set at P ≤0.05. RESULTS: The unilateral extraction group showed significant differences in transverse arch forms between the right and left sides in the anterior, anterior-middle, and middle segments of the arch, and all regions other than the posterior segment in the sagittal dimension. Significant differences were found between groups in the anterior and anterior-middle segments of the arch transversely, the middle and middle-posterior segments sagittally, and the midline deviation relative to the midsagittal plane. Superimposed average arches showed similar results. CONCLUSIONS: Unilateral maxillary extraction treatment generally results in a narrower and more posteriorly displaced arch form on the extraction side, with a deviated maxillary midline toward the extraction side of the arch.

Secular trends in the timing of skeletal maturation as assessed by the cervical vertebrae maturation method.

Objective: To investigate the presence of secular trends in skeletal maturation of girls and boys as assessed by the use of cervical vertebrae bones. Materials and methods: The study compared two main groups: the first included data collected from the Denver growth study (1930s to 1960s) and the second included data collected from recent pretreatment records (1980s to 2010s) of patients from the orthodontic clinic of a North American University. The records from the two groups were all for Caucasian subjects. The sample for each group included 78 lateral cephalographs for girls and the same number for boys. The age of the subjects ranged from 7 to 18 years. Cervical vertebrae maturation (CVM) stages were directly assessed from the radiographs according to the method described by Hassel and Farman in which six CVM stages were designated from cervical vertebrae 2, 3, and 4. Results: The mean age of girls from the Denver growth study and girls from the university clinic in each of the six CVM stages was not different at P ≤0.05. However, the mean age of boys from the two groups was not different only in stage 3 (P = 0.139) and stage 4 (P = 0.211). Conclusions: The results showed no evidence to indicate a tendency for earlier skeletal maturation of girls or boys. Boys in the university group started their skeletal maturation later than boys in the Denver group and completed their maturation earlier. Gender was a significant factor affecting skeletal maturation stages in both Denver and university groups.

Assessing Collagen and Micro-permeability at the Proanthocyanidin-treated Resin-Dentin Interface.

PURPOSE: To establish a fluorescence-based method to simultaneously assess micro-permeability and collagen cross-linking induced by chemical agents at the resin-dentin interface. MATERIALS AND METHODS: Three chemical agents were investigated (proanthocyanidin-rich grape seed extract: GSE; carbodiimide hydrochloride/N-hydroxysuccinimide: EDC/NHS; glutaraldehyde: GD) along with a control (distilled water) as primers applied on flat occlusal dentin surfaces of 48 teeth and restored with two commercially available etch-and-rinse adhesives. Resin-dentin interfaces were polished and infiltrated with rhodamine-B solution for confocal laser scanning microscopy analysis. Parameters were chosen that would allow acquisition of a simultaneous appearance of collagen and interfacial micro-permeability (rhodamine-B). Fluorescence emission intensity (FEI) was converted into numerals and values were calculated for each group. Data were statistically analyzed using one-way ANOVA and post-hoc Scheffe's and multiple comparisons tests (α = 0.05). T-tests with Pearson correlations were used to investigate correlations between collagen cross-linking and micro-permeability. RESULTS: The FEI of collagen was the highest for GD, followed by GSE, with no significant differences between EDC/ NHS and the control group (p > 0.05). Micro-permeability was significantly affected by the adhesives (p < 0.05). Micro- permeability was the lowest for GSE groups, regardless of the adhesives (p < 0.001). Weak correlations were found between micro-permeability and collagen auto-fluorescence. CONCLUSIONS: Non-enzymatic collagen cross-linking induced by GSE and GD can be detected by increased collagen auto-fluorescence, and results in reduced interfacial micro-permeability. Increased collagen auto-fluorescence was correlated with fluorescent collagen cross-links and decreased micro-permeability at the resin-dentin interface. Collagen auto-fluorescence is a useful tool to detect auto-fluorescent exogenous cross links and their potential impact on the quality of the resin-dentin interface.

Demineralization of resin-sealed enamel by soft drinks in a clinically relevant pH cycling model.

PURPOSE: To compare the in vitro protective effect of orthodontic sealants on the enamel demineralization under a soft drink-induced erosive challenge. METHODS: The facial surfaces of bovine incisors were sectioned into 5 mm x 4 mm x 4 mm enamel blocks. Specimens were randomly assigned to three surface protection measures: control (exposed enamel), coating with Transbond XT (unfilled resin primer), or coating with Opal Seal (filled and fluoride releasing primer). Thermocycling was used to simulate aging. The specimens were pH cycled through an acidic buffer, test beverage and a neutral buffer for a total of 7 days. Test beverages included water, Diet Mountain Dew, and Coke Classic. Quantitative light-induced fluorescence (QLF) images were taken at baseline and after aging. Final QLF images were taken to evaluate the demineralization of enamel. Data were analyzed statistically using a two-way ANOVA to compare the interaction between enamel surface protection and beverages as well as one-way ANOVA to compare surface protection and the test beverage levels. RESULTS: A statistically significant interaction was found between the surface protected groups and the test beverage groups (P < 0.05). Statistically significant differences were found among the test beverage groups (P < 0.05) and among the surface protection groups (P < 0.05). Coke Classic went through the sealant layer resulting in high enamel demineralization. Enamel coating with Opal Seal significantly reduced the erosive attack of beverages.

Correlations of spheno-occipital synchondrosis, cervical vertebrae, midpalatal suture, and third molar maturation stages.

OBJECTIVES: To estimate the joint correlations among cervical vertebrae maturation (CVM), spheno-occipital synchondrosis (SOS), midpalatal suture maturation (MPS), and third molar mineralization (TMM) and to assess the predictive potential of SOS on CVM and MPS. MATERIALS AND METHODS: 570 pretreatment cone-beam computed tomogram (CBCT) scans from three private practices were analyzed, and MPS, CVM, SOS, and TMM stages were categorized and recorded by two independent investigators. Intra- and inter-rater reliability tests were evaluated with weighted Cohen's kappa tests. Spearman correlation coefficients for ordinal data were used to estimate the pairwise correlations among SOS, CVM, MPS, and TMM. To evaluate if SOS could predict CVM and MPS, ordinal regression models were estimated and cross-validated. RESULTS: The analysis demonstrated a robust positive correlation between SOS and CVM (r = 0.845) and between SOS and MPS (r = 0.742). A significant correlation was also observed between CVM and MPS (r = 0.659). Further correlations were identified between TMM and SOS (r = 0.444), TMM and MPS (r = 0.392), and TMM and CVM (r = 0.358). Ordinal regression models indicated the potential of using SOS as a predictive marker for CVM and MPS stages. CONCLUSIONS: With a comprehensive analysis, SOS is strongly correlated with CVM and MPS, and SOS stage can be used to predict CVM and MPS using ordinal regression. Since MPS stages are challenging to categorize due to their anatomy, this finding suggests a diagnostic tool using SOS stages or when more information on skeletal maturity of the patient is desired.

Site specific properties of carious dentin matrices biomodified with collagen cross-linkers.

PURPOSE: To assess in non-cavitated carious teeth the mechanical properties of dentin matrix by measuring its reduced modulus of elasticity and the effect of dentin biomodification strategies on three dentin matrix zones: caries-affected, apparently normal dentin below caries-affected zone and sound dentin far from carious site. METHODS: Nano-indentations were performed on dentin matrices of carious molars before and after surface modification using known cross-linking agents (glutaraldehyde, proanthocyanidins from grape seed extract and carbodiimide). RESULTS: Statistically significant differences were observed between dentin zones of demineralized dentin prior to surface biomodification (P < 0.05). Following surface modification, there were no statistically significant differences between dentin zones (P < 0.05). An average increase of 30-fold, 2-fold and 2.2-fold of the reduced modulus of elasticity was observed following treatments of the three dentin zones with proanthocyanidin, carbodiimide and glutaraldehyde, respectively.

The Effects of Staining and Cleaning on the Color and Light Transmittance Changes of a Copolyester Retainer Material with Different Surface Textures.

This study evaluated the efficacy of different cleaning methods with respect to changes in the color and light transmittance of both rough and smooth thermoformed, copolyester retainer specimens, after staining in different solutions. Four hundred copolyester sheets (Essix ACE) specimens were fabricated over molds with different surface textures, smooth and rough. The specimens were stained in four different solutions (n = 100 per solution) over 28 days; then, each of the four groups of 100 stained specimens was sub-divided into five groups of 20 specimens and subjected to a different destaining solution. The specimens were sub-divided with half subjected to an additional ultrasonic cleaning procedure. Light transmittance and color changes were analyzed using a spectrometer/integrating sphere assembly and a spectrophotometer. Mean difference comparisons were performed using appropriate statistical tests at p = 0.05. All five destaining solutions proved to be effective at removing coffee and tea stains. The surface roughness of the retainer material plays a significant role in the ability of cleaning solutions to remove stains, demonstrating a greater effect on cleaning rough specimens with respect to improvements in light transmittance and greater changes in color. Additionally, an ultrasonic cleaning unit generally enhanced the ability of all five solutions to clean the tea-stained specimens. However, the enhancements were only significant for light transmittance.