Age estimation of Hispanic children in the United States: Development and validation of dental reference dataset based on two staging systems.

Dental tissues follow a systematic pattern of development and several radiological methods have been developed and validated. This study aims to develop and validate a reference data set (RDS) for dental development of Hispanic children and to compare the mean age using the Demirjian and Moorrees tooth developmental stage (TDS) systems. A total of 600 Dental Panoramic Tomographs (DPTs) of Hispanic children aged 6 to 17 years were obtained and reference datasets (RDS) were developed by scoring all the maxillary and mandibular teeth in the left side of the arch according to the Demirjian (8 stage) and Moorrees (14 stage) scoring systems. To validate the RDS, 120 (DPTs) separate from the RDS were randomly selected, and dental ages were calculated from the RDS using unweighted and five weighted mean average methods. Statistical significance was set at p < 0.05, and a paired t-test was conducted to compare the difference between Chronological Age (CA) and Dental Age (DA) for each weighting method. For the 8-stage system, the mean (sd, se) difference between CA and DA for the unweighted method was 0.04 (0.51, 0.065) years for males, and 0.07 (0.41, 0.053) years for females. The difference was not statistically significant for all five weighting methods (p > 0.05). For the 14-stage system, CA-DA for the unweighted method was 0.17 (0.33, 0.042) years for males, and 0.13 (0.41, 0.053) years for females. The difference was statistically significant for most of the Moorrees methods (p < 0.05). Dental age derived from the unweighted average method using the reference dataset derived from Demirjian's 8-stage system is recommended for dental age estimation in Hispanic children and adolescents.

Teaching evidence-based practice at the University of Texas Health Science Center at San Antonio dental school.

The overarching goal of the Evidence-Based Practice Program at San Antonio is to provide our graduates with life-long learning skills that will enable them to keep up-to-date and equip them with the best possible patient care skills during their 30-40 years of practice. Students are taught to (1) ask focused clinical questions, (2) search the biomedical research literature (PubMed) for the most recent and highest level of evidence, (3) critically evaluate the evidence, and (4) make clinical judgments about the applicability of the evidence for their patients. Students must demonstrate competency with these "just-in-time" learning skills through writing concise one-page Critically Appraised Topics (CATs) on focused clinical questions. The school has established an online searchable library of these Critically Appraised Topics. This library provides students and faculty with rapid, up-to-date evidence-based answers to clinical questions. The long-range plan is to make this online library available to practitioners and the public.

Prevention of white spot lesions around orthodontic brackets using organoselenium-containing antimicrobial enamel surface sealant.

OBJECTIVES: To investigate the antimicrobial potential of organo-selenium compound when applied as enamel surface sealant or primer (DenteShield™ [DS]) around orthodontic brackets to prevent enamel demineralization. METHODS: Human teeth were randomly assigned to seven treatment groups (15/group): control (No primer or sealant), Leopard light primer (LLP), DS Primer (DS-P), DS Enamel Surface Sealant (DS-S), Pro Seal, Opal Seal and combined DS-P/DS-S (DS-PS). Following etching, the tooth surface was coated with their respective material (except control group) and a bracket was bonded on each treated surface. All samples were subject to cariogenic challenge in a continuous flow microbial caries model at 37 °C in an incubator for 28 days. Demineralization was evaluated with Transerse microradiography to determine mineral loss (Δz) and lesion depth (LD). Data was statistically analyzed using Bonferroni protected Mann-Whitney tests (α = 0.05). RESULTS: Demineralization was obsessrved only in Control and LLP groups. Control group had significantly (p < 0.001) greater mean LD (109.47 ± 34.22 µm) and mean Δz (2251.07 ± 514.26 vol%µm) when compared with the LLP with mean LD (44.98 ± 11.69 µm) and Δz (700.67 ± 310.66 vol%µm). All other groups did not develop any lesions. CONCLUSIONS: Selenium-based primer and sealant used alone or in combination were effective in protecting enamel from demineralization around brackets. The combination of primer and enamel surface sealant has no added benefit. SIGNIFICANCE: DS-S and DS-P containing antimicrobial organo-selenium compound can prevent whitespot lesions development when applied on tooth surface during orthodontic treatment. Light primer applied alone on tooth surface may not provide adequate protection for the enamel around orthodontic appliances.

Effect of JPEG2000 compression on landmark identification of lateral cephalometric digital radiographs.

INTRODUCTION: As digital imaging improves and digital cephalometric radiography becomes more prevalent, the need for digital storage space and transmission speed will increase. Compression of the image files is 1 method to overcome transmission overload. However, compression could compromise image quality. The purpose of this study was to determine the range of compression ratios, by using the JPEG2000 standard, within which the identification of landmarks on cephalometric radiographs is not compromised. METHODS: Ten lateral cephalometric digital images were used. Six raters identified 19 landmarks under controlled viewing conditions. The images included the original uncompressed TIFF image and the JPEG2000 format at 3:1, 12:1, 50:1, and 110:1 compression ratios. The images were randomized and displayed with image processing software. The x and y coordinates of each landmark were recorded. RESULTS: All compression ratios performed equally well compared with the original images with the exception of A-point and nasion at 110:1 and gonion at 3:1 compression ratios. All landmark identifications were precise with the exception of the maxillary incisal apex and edge at the 12:1 and 50:1 compression ratios, respectively. CONCLUSIONS: JPEG2000 is a reliable file format that can be implemented in orthodontic practice.

Comparison of photothermal radiometry and modulated luminescence, intraoral radiography, and cone beam computed tomography for detection of natural caries under restorations.

OBJECTIVES: The aim of this ex vivo study was to measure the sensitivity, specificity, and receiver operating characteristic (ROC) area under the curve (AUC) of a caries diagnostic system based on photothermal radiometry and modulated luminescence (PTR/LUM) and compare them with the values for digital intraoral radiography (IR) and cone beam computed tomography (CBCT) in detecting recurrent decay. STUDY DESIGN: Class 2 composite restorations were prepared on 70 proximal surfaces: 35 with caries and 35 without caries. The gingival floor of the restored surfaces was assessed for caries under the restorations using each of the 3 modalities. Statistical calculations and analysis were performed using the R statistical computing environment. RESULTS: The average scores for sensitivity among the 6 observers were 0.89 for PTR/LUM, 0.38 for IR, and 0.40 for CBCT. Sensitivity for PTR/LUM was significantly greater than sensitivity for IR and CBCT. Average scores for specificity were 0.83, 0.80, and 0.70 for PTR/LUM, IR, and CBCT, respectively. CBCT had significantly lower specificity. The AUC was 0.65 for IR and 0.59 for CBCT, which were significantly different. PTR/LUM had moderate intraobserver agreement. CONCLUSIONS: PTR/LUM, which involves non-ionizing radiation, can serve as a sensitive adjunct in early caries detection and monitoring.

Esthetic preferences of European American, Hispanic American, Japanese, and African judges for soft-tissue profiles.

INTRODUCTION: Our objectives were to determine whether observer and patient sex and race or ethnicity determine esthetic preferences for lip positions. METHODS: Four independent panels each consisting of 30 lay judges viewed pretreatment silhouette profiles of 10 European American, 10 Japanese, and 10 African American Angle Class I and Class II orthodontic patients. The panels included European Americans, Hispanic Americans, Japanese, and Africans. Profiles were traced from lateral cephalograms and manipulated so that the lip profile lay on the Ricketts' E-line or at various distances from the E-line from -8 to +4 mm in 2-mm increments. The judges selected the profile that they considered the most attractive and then classified the remaining 6 profiles as either acceptable or unacceptable. RESULTS: The mean preferred lip positions (mean +/- SD) were -2.58 +/- 1.92 mm for European American, -3.28 +/- 2.26 mm for Hispanic American, -3.45 +/- 1.92 mm for Japanese, and -2.13 +/- 1.95 mm for African judges. The African judges preferred more protrusive profiles compared with the Hispanic American (P <0.01) and Japanese (P <0.001) judges. Patient race or ethnicity and sex also contributed significantly to the judgments of profile esthetics (P <0.001). CONCLUSIONS: Judge race or ethnicity and patient race or ethnicity and sex significantly influence laypersons' standards for lip profile esthetics.

Evaluation of the caries-preventive effect of toothpaste containing surface prereacted glass-ionomer filler.

AIM: Although fluoride interventions have the most consistent benefit in preventing caries, caries still develop in high-risk individuals. Authors have evaluated the effectiveness of toothpastes containing surface prereacted glass-ionomer (S-PRG) filler in preventing tooth demineralization. METHODS: Human tooth enamel blocks were randomly assigned to six groups (30 blocks/group): no treatment (a), and toothpaste containing either 1500 ppm fluoride as sodium monofluorophosphate (NaMFP) (b), 0 wt% S-PRG (b), 1 wt% S-PRG (d), 5 wt% S-PRG (e), or 20 wt% S-PRG (f). Early caries developed on each block by 7-days demineralization using a microbial caries model. Mineral loss (Δz) and lesion depth (LD) were determined using transverse microradiography. RESULTS: Relative to the control, all toothpastes, except 0% S-PRG, significantly (analysis of variance, Tukey's, P<.0001) reduced Δz and LD at varying percentages. With regard to Δz, all comparisons were significant (P<.0001), except 0% S-PRG vs the control. Otherwise, S-PRG 1%, 5%, and 20% had 0.50, 0.37, and 0.27 times Δz compared to the control, respectively, while NaMFP had 0.61 times Δz compared to the control. LD followed an almost similar trend as Δz. CONCLUSIONS: The findings of the present study demonstrate the effectiveness of toothpaste containing S-PRG filler in inhibiting tooth demineralization in the presence of bacterial plaque, thus highlighting its potential as an effective caries-control tool for individuals at high risk of developing caries.

Conditional deletion of cytochrome p450 reductase in osteoprogenitor cells affects long bone and skull development in mice recapitulating antley-bixler syndrome: role of a redox enzyme in development.

NADPH-cytochrome P450 oxidoreductase (POR) is the primary electron donor for cytochromes P450, dehydrocholesterol reductase, heme oxygenase, and squalene monooxygenase. Human patients with specific mutations in POR exhibit severe developmental malformations including disordered steroidogenesis, sexual ambiguities and various bone defects, similar to those seen in patients with Antley-Bixler syndrome (ABS). To probe the role of POR during bone development, we generated a conditional knockout mouse (CKO) by cross breeding Por (lox/lox) and Dermo1 Cre mice. CKO mice were smaller than their littermate controls and exhibited significant craniofacial and long bone abnormalities. Differential staining of the CKO mice skull bases shows premature fusion of the sphenooccipital and basioccipital-exoccipital synchondroses. Class III malocclusion was noted in adult knockout mice with an unusual overgrowth of the lower incisors. Shorter long bones were observed along with a reduction in the bone volume fraction, measured by microCT, in the Por-deleted mice compared to age- and sex-matched littermate controls. Concerted up- or down-regulation of proteins in the FGF signaling pathway observed by immunohistochemistry in the tibia samples of CKO mice compared to wild type controls shows a decrease in the FGF signaling pathway. To our knowledge, this is the first report of a mouse model that recapitulates both skull and long bone defects upon Por deletion, offering an approach to study the sequelae of POR mutations. This unique model demonstrates that P450 metabolism in bone itself is potentially important for proper bone development, and that an apparent link exists between the POR and FGF signaling pathways, begging the question of how an oxidation-reduction flavoprotein affects developmental and cellular signaling processes.

A comparison of stability between delayed versus immediately loaded orthodontic palatal implants.

INTRODUCTION: Control of anchorage is a fundamental problem in orthodontics. Conventional means of controlling anchorage are characterized by potential disadvantages and inconveniences: visibility, compliance dependence, risk of undesirable side effects, and injury. Titanium implants have evolved as a potential clinical alternative in overcoming the limits of conventional dental orthodontic anchorage. METHODS: This project was designed as a prospective observational study on 20 patients whose treatment plans required maximum (stable) anchorage during orthodontic treatment. The patients received palatal implants (Institut Straumann AG, Waldenburg, Switzerland: length of implant 4-6 mm, diameter 3.3 mm), which were placed into the midpalate. The goal of this study was to evaluate if the implant could be loaded immediately, or if time should be allowed for integration. Patients were randomized into two groups; one group had their implants loaded immediately with a coil spring, and the second group remained nonloaded, with an annealed coil spring, for the 8-week experimental period. Measurement of implant stability was taken using resonance frequency analysis on both groups at the time of implant placement and at 8 weeks post-placement. RESULTS: This study demonstrated that immediate loading of the Straumann orthodontic implant is possible, based on the clinical success observed in both groups. However, compared with the nonloaded group, the stability of the immediately loaded implant was significantly less at 8 weeks. The mean implant stability quotient (ISQ) of the nonloaded group was 38.7 kHz at baseline and 47.3 kHz after 8 weeks. The mean ISQ of the loaded group was 42.0 kHz at baseline and 38.4 kHz after 8 weeks. Statistical analysis showed a significant difference between the group that was loaded and the nonloaded group after 8 weeks (p < 0.05). CONCLUSION: Based on the results of this study, an unloaded healing period provides for increased stability of the implants compared with immediately loaded palatal implants. CLINICAL SIGNIFICANCE: Patients often like to have their orthodontic treatment begin as soon as possible. This study examined if palatal implants could be loaded immediately after placement so overall treatment time could be decreased. It appears that this is possible based on the results of the study; however, an unloaded healing period results in a more stable implant.