The limit of mandibular incisor correction is dependent on the amount of crowding and the incisor position within the mandibular alveolar bone. Moving teeth outside of the alveolar bone can have detrimental effects on the periodontium. The purpose of this study was to evaluate in 3D incisor angulation, B point, root apex position changes, facial and lingual cortical bone thickness at four levels on each tooth, and 2D lower incisor angulation to the true vertical plane and intercanine width changes. Pre- and post-treatment Cone Beam Computed Tomography images of 67 orthodontic patients were included from the BU repository. 276 mandibular incisors and 138 canines were evaluated. A mandibular plane was used as a horizontal reference plane. 3D measurements of angular changes in apex to constructed Menton plane for all four lower incisors increased by a statistically significant amount. (p<0.0001) Intercanine width (p=0.0032), arch length discrepancy (p<0.0001) incisor angulation for each incisor also showed statistically significant differences (mean change 2.3°, mean p=0.009). Changes in L1-NB were also found to be statistically significant (p < 0.005). Incisor bone thickness changes were statistically significant. Lingual bone change in LL1 at point A, was –0.18 mm, p=0.0072: at point B, -0.38, p<0.0001: at point C, -0.56, p<0.0001: at apex point -0.65 mm, p<0.0001. Similar lingual bone thickness changes were noted for all incisors. The results show that lingual bone loss increased from superior reference point (A) to apex, suggesting that roots are tipped around the center of resistance.

OBJECTIVES: The purpose of this study was to evaluate the effects of clinical-used cleansers on the color stability of temporary restorative materials via spectrophotometric analysis. MATERIALS AND METHODS: A total of 256 specimens fabricated from four temporary restorative materials (Protemp™ Plus; Tempsmart™; Jet Tooth Shade™; VITA CAD-Temp™) were soaked for ten minutes or three hours in the following cleanser: temporary cement remover ultrasonic cleaning solution (TS), general purpose ultrasonic cleaning solution (GS), plaster and stone remover ultrasonic cleaning solution (PS) or water (control). Subsequently, the specimens were immersed for twenty-four hours in a blueberry juice or water (control). This procedure was repeated three cycles. Color measurements were performed by spectrophotometer after every immersion. Color differences (Delta E*) were evaluated using the CIE L*a* b* color system. Results were submitted to analysis of variance and Tukey honest significant difference test (p<0.001). Data were analyzed statistically by repeated measures (ANOVA); one, two and three way ANOVA, and Tukey HSD multiple comparison tests. RESULTS: Under the conditions of this study, Jet Tooth Shade™ was more color stable. Tempsmart™ displayed greater color change, especially in PS and TS. In ten minutes cleaning protocol, the color changes in all temporary restorative materials were demonstrated clinically acceptable color changes for all cleaning solutions during the three repeated cycles of immersion in cleansers. CONCLUSIONS: All the clinical cleansers used in the study affected the color values of temporary restorative materials. Furthermore, Delta E* values increased along with the number of immersion cycles and immersion time.

BACKGROUND: Orthodontic tooth movement is a complex process involving a number of inflammatory and anabolic/catabolic pathways. Further, successful treatment depends on proper timing of orthodontic measures with regard to patient’s growth spurt. Saliva analysis has emerged as a non-invasive collection method to track biomarkers relevant to both tooth movement biology and growth prediction. The aim of the present study was to analyze changes in tooth movement and assess relationships with salivary levels of alkaline phosphatase, IGF-1, TGF-β1, testosterone, BMP-2, BMP-4, and BMP-9t. METHODS: Twenty seven healthy patients (17 females, 10 males) with a mean age of 13.3 years, undergoing orthodontic treatment with a non-extraction treatment plan were selected for the study. Height, weight, and other demographic features were recorded; maxillary and mandibular alginate impressions were obtained, and 10 mL saliva samples were taken at the initial visit (T0), after 4 weeks (T1), 3 months (T2), and then at 3-month intervals (T3, T4, T5). Casts were made from alginate impressions. Little’s Irregularity Index, intercanine widths, intermolar widths, arch lengths, and tooth widths were measured. Saliva samples were analyzed for the concentrations of alkaline phosphatase, IGF-1, TGF-β1, testosterone, BMP-2, BMP-4, and BMP-9 by multiplex immunoassay and/or ELISA. Data were analyzed using correlation coefficients and ANOVA. RESULTS: Over the six timepoints, there were statistically significant changes in the level of testosterone (p < 0.05) and Little’s Irregularity Index (p < 0.01), with the most significant changes occurring at the beginning of treatment (T0 to T1). Statistically significant correlations (p < 0.05) were observed between testosterone and height/weight, intercanine width and intermolar width, BMP-4 and intercanine/intermolar width, alkaline phosphatase and testosterone, alkaline phosphatase and TGF-β1, and among the BMPs. CONCLUSION: The changes in Little’s Irregularity Index reflects successful progress of the orthodontic treatment. The correlations observed among the various salivary concentrations suggest a number of further directions for study.

INTRODUCTION: The standard process of evaluating craniofacial structures on planar radiographs is being replaced by 3D evaluation using low dose cone beam tomography images. However, current 3D analyses are still using the traditional landmarks from the 2D analysis as references. In the world of 3D, the literature is lacking adequate landmarks that take advantage of the 3-dimensional nature of these 3D images. The objective of the study was to evaluate the reliability and reproducibility of identifying various landmarks specific to a CBCT. These landmarks include points from traditional cephalometric analysis and points which are uniquely found on CBCT. The landmarks were strategically selected in order to represent different parts of the skull utilized in three dimensional cephalometric measurements. METHODS: Fifty CBCT datasets of Skeletal Class I, normodivergent patients without any noticeable craniofacial deformities from a CBCT repository were included in the study. Landmarks were chosen from diverse parts of the skull that ranged from bony landmarks, foramina and the teeth using a 3d prototyping software, Mimics ® v18.0(Materialise, Leuvem Belgium). Three examiners relocated the landmarks three separate times. Coordinates were recorded in the x, y and z axes. Intra- and inter-examiner reliabilities were calculated using the interclass correlation coefficient (ICC) along with the demographic data. RESULTS: Bony protrusions such as the lingulae, and the crista galli or tips of the incisor teeth proved to be the most reproducible with the highest reliability between the three examiners readings. The vast majority of the landmarks had good (>.75) to excellent (>.9) mean ICC. CONCLUSION: Choosing different landmarks specific for CBCTs were found to have good to excellent reliability between examiners who are properly trained to find the points. These points may represent a new type of standard when determining landmarks for 3-D evaluation of the skull.

Little knowledge and contradictory results are available on the effectiveness of incisor malalignment as an indicator of poor oral health (e.g., dental caries, periodontal disease). This research project aimed to examine the relationship between incisor malalignment and two common diseases of poor oral health—periodontal disease and dental caries—and their cumulative outcome (i.e., tooth loss) in anterior teeth. Prospective and cross-sectional data from the Veterans Affair (VA) Dental Longitudinal Study were utilized in this research. Incisor malalignment traits were measured by determining the anterior tooth size–arch length discrepancy index (aTSALD) and Little’s Irregularity Index (LII). Incisor malalignment indices were categorized by severity. We computed per arch adjusted estimates of the amount of change/events in anterior periodontal disease, tooth loss, and dental caries (i.e., coronal and root caries) by the level of the incisor malalignment traits. Pocket depth (PD), clinical attachment loss (CAL), and alveolar bone loss (ABL) were used as periodontal disease outcomes. Prospective data included information from 400 maxillary and 408 mandibular casts with a complete set of anterior sextants. In the upper anterior arch, crowding and spacing were significantly associated with an increased mean PD. Maxillary incisor irregularity involved a significantly increased mean CAL. In the anterior mandibular arch, incisor crowding and irregularity were significantly associated with increased PD, CAL, and ABL. Prospective data to test the association between all-cause tooth loss and incisor alignment traits included a sample size of 400 maxillary and 408 mandibular casts with a complete set of anterior sextants. Maxillary segments with spacing had a 401% significantly greater hazard (hazard ratio [HR]= 5.01, 95% confidence interval [CI] = 1.16-21.64) of all-cause tooth loss, compared to the ideal alignment (i.e., the reference group). Multiple cross-sectional data to test the association between anterior dental caries outcomes and malalignment traits included a sample size of 211 maxillary and mandibular casts with a complete set of anterior sextants. Compared to ideally aligned teeth, spacing in the maxillary segment significantly decreased the mean maxillary anterior CDFT by 0.93 teeth. Specific malalignment traits may be linked to certain poor oral health indicators. / 2018-09-28T00:00:00Z

OBJECTIVES: This study has three aims: 1) to determine the trends and prevalence of dental fluorosis and caries among persons aged 6-19; 2) to examine the association between dental fluorosis and caries among persons of the same age group; and 3) to investigate the influence of dental fluorosis and caries on oral health-related quality of life (OHRQoL) among people aged 16-49 in the United States. METHODS: The data from the National Health and Nutrition Examination Survey (NHANES) 1999-2004 and 2011-2012 were analyzed. For aims 1) and 2), individuals aged 6-19 years, who completed the home interview and oral health examination were included (n=9,493, n=2,411, respectively). For aim 3, the data from NHANES 2003-2004 were analyzed including only people aged 16-49, who completed the home interview and both conditions examination (n=3,035). The reason behind age restriction is that people aged 16-49 were targeted to answer OHRQoL questions. Dental fluorosis was measured by Dean’s Index (6-categories of severity), where classification was based on the two teeth most affected by fluorosis. Dental caries experience was measured by DMFS score (overall caries experience and untreated decay). OHRQoL was calculated as sum of 7 items out of the 14 items NHANES Oral Health Impact Profile (OHIP-14). OHRQoL score can range 6-28 (lower score indicates better oral health). Other covariates were socio-demographic characteristics, self-perceived mouth/teeth condition (1-item), and previous dental visit (time and reason). Bivariate and multivariate analyses were conducted with caries and OHRQoL as outcomes. All analyses were weighted and adjusted for the complex design of the NHANES survey, using SAS 9.3 survey procedures. RESULTS: For aim 1, dental fluorosis prevalence among persons aged 6-19 was increasing (37% vs. 57%) from 1999-2004 to 2011-2012. There was a significant increase in caries experience and a significant decrease in untreated tooth decay from 1999-2004 to 2011-2012 among persons aged 6-19. For aim 2, the crude association between the severity of fluorosis and DMFS was significantly inversely proportional except for the moderate/severe categories of fluorosis where the relationship was linear. For aim 3, the bivariate all teeth analysis showed that OHRQoL was significantly decreased with higher level of fluorosis severity (p-value=0.05). Severity of fluorosis was significantly inversely associated with DMFS score (β-coefficient=-4.8, p-value <0.0001). The lower DMFS scores explain the better perception of oral health (lower OHRQoL scores) in higher fluorosis severity groups. However, after controlling of DMFS and covariates in a multiple regression model, fluorosis severity was not significantly associated with lower OHRQoL score. CONCLUSIONS: Overall, the findings of this study suggest that the prevalence of dental fluorosis is increasing while untreated decay is decreasing among persons aged 6-19. The results demonstrated a clear inverse relationship between dental fluorosis and caries. The findings also suggest that the benefit of fluorides outweighs the esthetic impact of fluorosis among the U.S children and adolescents. / 2018-09-28T00:00:00Z

Oral squamous cell carcinoma represents more than 90% head and neck cancers with high incidence rate and morbidity. To date, little is known about the molecular mechanisms responsible for OSCC initiation and progression to advanced disease. Thus, identifying key pathways involved in OSCC pathobiology is likely to lead to the identification of new druggable targets and future anti-cancer therapies. Work from our laboratory has linked the metabolic pathway of protein N-glycosylation with OSCC biology. Specifically, overexpression of the first N-glycosylation gene, DPAGT1, in human OSCC tumor specimens was shown to be associated with aberrant activation of canonical Wnt signaling and inhibition of mature E-cadherin junctions. The purpose of this study was to examine how increased N-glycosylation was associated with OSCC growth and metastatic properties in cellular and murine models. We show that high level of DPAGT1 expression correlates with increased cell surface modification of malignant OSCC HSC-3 cells with complex N-glycans. Further, HSC-3 cells are hypersenitive to the N-glycosylation inhibitor, tunicamycin, suggesting that aggressive properties of OSCC cells depend, in part, on the N-glycosylation pathway. Lastly, we show that orthotopic HSC-3 cell-derived tumor xenografts are inhibited by tunicamycin both in overall growth and metastases, indicating that targeting DPAGT1 and N-glycosylation may represent a new strategy for the treatment of OSCC in human patients.

PURPOSE: To evaluate and compare the failure load of milled and bonded IPS e.max CAD and VITA ENAMIC endocrowns used in the restoration of endodontically molar teeth. MATERIALS AND METHODS: Typodont tooth # 30 was prepared with a central cavity to support the endocrowns. Fifty-eight epoxy resin dies were made from a physical impression of the prepared tooth and scanned with an intra oral scanner (Cerec AC, Dentsply-Sirona). The designed restorations were milled from two different materials: VITA ENAMIC (n=30) and IPS e.max CAD (n=28). Following adhesive cementation, half of the endocrowns of each group were subjected to thermal aging, each specimen was obliquely loaded until failure. Four groups were tested: group 1 (Enamic endocrowns without thermocycling), group 2 (Enamic endocrowns + thermocycling), group 3 (e.max endocrowns without thermocycling) and group 4 (e.max endocrowns + thermocycling). The fracture mode characteristics were identified. RESULTS: There was a significant difference in the mean failure loads between group 4 and group 3 at P ≤ 0.05; also between group 4 and group 1 at P ≤ 0.05. Group 1 had the highest value of 2301 N. A visual inspection of all tested endocrowns revealed four different failure modes; 1-Adhesive failure, 2-Cohesive failure, 3-Mixed failure and 4-Fracture Initiation In Crown Propagating Through Die. CONCLUSION: Thermocycling decreased the load to failure significantly for IPS e.max CAD endocrowns. Mode of failure 4 and 1 were the dominant failure modes for VITA ENAMIC and IPS e.max CAD respectively. / 2019-10-27T00:00:00Z

Periodontal disease, gingivitis and periodontitis are conditions that are a result of local response to supragingival dental plaque that forms due to poor personal oral hygiene. This is initiated by accumulation of bacterial biofilm on the teeth that leads to inflammatory changes in the gingival tissue. The pathogenesis of periodontitis has a multi-level architecture, composed of bacterial composition, environmental and genetic factors. Disruption of the oral biofilm by mechanical methods is one of the best alternatives for preventing periodontal disease. The present intervention study aimed at decreasing the gingival inflammation in 36 patients with gingivitis or mild to moderate periodontitis by administration of a new dental product composed of antioxidants (dental foam). This study was conducted as a proof-of-concept study over 42 days and aimed to observe the earliest changes in gingival inflammation as measured by gingival index and bleeding on probing. Clinical periodontal parameters including gingival index, bleeding on probing, plaque index and probing pocket depth were assessed at baseline, and 14, 28 and 42 days after baseline. Subjects in both treatment (n=24) and control (n=12) groups were given standard oral hygiene instructions including brushing with a standard toothbrush (Oral B® Pro health medium) and standard toothpaste (GLO Science Toothpaste) twice a day. Subjects in test group used the dental foam in addition to the standard toothpaste twice a day, while control group subjects did not use any additional product. The statistical analyses were performed to compare the mean changes from baseline to each post baseline time points using Student’s t-test. All statistical tests were conducted at p< 0.05 level of significance. There was a statistically significant reduction in the primary endpoints, gingival index (p=0.003) and bleeding on probing (p=0.007) in the test group when compared to the control group over 42 days. There were no statistically significant differences in the secondary outcomes, plaque index (p=0.07) and pocket depth (p= 0.12) between two groups. Oral hygiene care including mechanical plaque removal with standard tooth brushing in combination with application of newly developed dental product (dental foam) has shown significant reduction in gingival inflammation when compared to standard tooth brushing alone and reveals beneficial effects in patients with gingivitis and mild to moderate periodontitis.

OBJECTIVES: To analyze the polymerization shrinkage stresses flowable and universal dental composites at different times. MATERIALS AND METHODS: Seven flowable and four universal composites; were used in this study. Two glass cylinders were fixed in a vertical position on the INSTRON machine; leaving 1 mm gap between them. The resin was injected and light cured for 20 seconds. The load curve was recorded until 5 mins after the end of light cure. The stress values were calculated in MPa from the division of contraction forced recorded at 20 s. 60 s.180 s. and 300 s. Statistical analysis was done using ANOVA and all Pairs Tukey –Kramer (α = 0.05) RESULTS: MPa Seconds MPa Seconds Sure Fil SDR 0.18 20 0.33 300 Filtek Sup. Ultra univ. 0.21 20 0.37 300 Filtek Sup. Ultra Flow 0.39 20 0.55 300 NovaPro Ultra univ. 0.39 20 0.55 300 Beautifil II univ. 0.35 20 0.57 300 NanoPro Flow 0.40 20 0.66 300 Herculite Ultra univ. 0.43 20 0.65 300 Herculite Ultra Flow 0.42 20 0.66 300 Prime Dent 0.38 20 0.85 300 G-aenial Flo 0.64 20 0.90 300 Dentex flow 0.71 20 1.12 300 CONCLUSIONS: Within the limitation of these research we can conclude that: In general the flowable composites group presented higher polymerization shrinkage stress values at all sudied times. Our null hypothesis ”there is no shrinkage stress difference between flowable and universal composites” was partialy rejected, since the flowable composite SureFil SDR obtained the lowest shrinkage stress values in our study. / 2018-09-28T00:00:00Z