Ana Nora Donaldson

A biomarker-based mathematical model to predict bone-forming potency of human synovial and periosteal mesenchymal stem cells.

OBJECTIVE To develop a biomarker-based model to predict osteogenic potency of human mesenchymal stem cells (MSCs) from synovial membrane and periosteum. METHODS MSC populations were derived from adult synovium and periosteum. Phenotype analysis was performed by fluorescence-activated cell sorting and real-time reverse transcriptase-polymerase chain reaction (RT-PCR). Telomere lengths were determined by Southern blot analysis. In vitro osteogenesis was assessed quantitatively by measurements of alkaline phosphatase activity and calcium deposits. To investigate bone formation in vivo, MSCs were seeded onto osteoinductive scaffolds and implanted subcutaneously in nude mice. Bone was assessed by histology, and the human origin investigated by in situ hybridization for human Alu genomic repeats. Quantitation was achieved by histomorphometry and real-time RT-PCR for human osteocalcin. Analysis at the single-cell level was performed with clonal populations obtained by limiting dilution. Multiple regressions were used to explore the incremental predictive value of the markers. RESULTS Periosteal MSCs had significantly greater osteogenic potency than did synovial MSCs inherent to the single cell. Bone was largely of human origin in vivo. Within the same tissue type, there was variability between different donors. To identify predictors of osteogenic potency, we measured the expression levels of osteoblast lineage genes in synovial and periosteal clonal MSCs prior to osteogenic treatment. We identified biomarkers that correlated with osteogenic outcome and developed a mathematical model based on type I collagen and osteoprotegerin expression that predicts the bone-forming potency of MSC preparations, independent of donor-related variables and tissue source. CONCLUSION Our findings indicate that our quality-control mathematical model estimates the bone-forming potency of MSC preparations for bone repair.

Supplemental Vibrational Force During Orthodontic Alignment A Randomized Trial

This prospective 3-arm parallel-group randomized clinical trial investigated the effect of supplemental vibrational force on rate of orthodontic tooth alignment with fixed appliances. Eighty-one subjects (40 males, 41 females; mean age, 14.1 y) undergoing first premolar extraction-based fixed appliance treatment were randomly allocated to treatment supplemented with daily use (20 min) of a removable intraoral vibrational device (AcceleDent; OrthoAccel Technologies Inc.; n = 29), an identical nonfunctional (sham) device (n = 25), or fixed appliances only (n = 27). Mandibular study casts were taken at baseline (treatment start: placement of 0.014-in. nickel-titanium arch wire), initial alignment (0.018-in. nickel-titanium arch wire), and final alignment (0.019 x 0.025–in. stainless steel arch wire). Overall mean irregularity index in the mandibular arch at baseline was 8.5 ± 3.8 mm (95% CI, 7.6 to 9.3) with no significant difference between groups (P = 0.73). For the total sample, mean irregularity index at initial alignment was 2.7 ± 2.8 mm (95% CI, 2.2 to 3.4) with no significant difference between groups (P = 0.40). Mean time from baseline to initial alignment was 59 ± 25 d (95% CI, 54.5 to 65.6); from initial to final alignment, 150 ± 62.5 d (95% CI, 136 to 165); and baseline to final alignment, 209 ± 65 d (95% CI, 195 to 224). Kaplan-Meier analysis demonstrated that patterns of alignment were not significantly different among the 3 groups (P = 0.66). Multivariate linear regression for initial and overall alignment rates using initial irregularity index as the covariate showed no significant differences among groups. The most important influence on both initial and overall rates of alignment was initial irregularity (P = 0.1 × 10−4). This prospective randomized clinical trial found no evidence that supplemental vibrational force can significantly increase the rate of initial tooth movement or reduce the amount of time required to achieve final alignment when used in conjunction with a preadjusted edgewise fixed appliance (ClinicalTrials.gov NCT02314975).

Assessing the influence of lower facial profile convexity on perceived attractiveness in the orthognathic patient, clinician, and layperson

OBJECTIVE The aim was a quantitative evaluation of how the severity of lower facial profile convexity influences perceived attractiveness. STUDY DESIGN The lower facial profile of an idealized image was altered incrementally between 14° to -16°. Images were rated on a Likert scale by orthognathic patients, laypeople, and clinicians. RESULTS Attractiveness ratings were greater for straight profiles in relation to convex/concave, with no significant difference between convex and concave profiles. Ratings decreased by 0.23 of a level for every degree increase in the convexity angle. Class II/III patients gave significantly reduced ratings of attractiveness and had greater desire for surgery than class I. CONCLUSIONS A straight profile is perceived as most attractive and greater degrees of convexity or concavity deemed progressively less attractive, but a range of 10° to -12° may be deemed acceptable; beyond these values surgical correction is desired. Patients are most critical, and clinicians are more critical than laypeople.

Assessing the Influence of Asymmeftry Affecting the Mandible and Chin Point on Perceived Attractiveness in the Orthognathic Patient, Clinician, and Layperson

PURPOSE The purpose of this investigation was to undertake an objective and quantitative evaluation of how severity of asymmetries affecting the mandible and chin point influence perceived attractiveness. MATERIALS AND METHODS The mandible and chin point of idealized male and female frontal facial images were altered in 5-mm increments from 0 to 25 mm and to the left and right, to represent horizontal, vertical, and combined asymmetry affecting these regions. These images were rated on a 7-point Likert scale by a preselected group of orthognathic patients before treatment, clinicians, and laypeople. RESULTS In relation to a 5-mm asymmetry, observers progressively decreased attractiveness ratings and increased the desire for surgery for greater asymmetries. Clinicians and patients were found to be more critical than laypeople. The desire for surgery decreased by 3% for each year increase in age, was 53% less for men, and 45% greater for white observers. CONCLUSIONS Asymmetry of 10 mm is perceived as being significant; at 5 mm and below, it is largely unnoticed. The greater the degree of asymmetry greater than 10 mm, the more noticeable and the greater the desire was for correction. Clinician and patient ratings were similar and more critical than ratings of laypeople. A desire for surgery was negligible for 5 mm of asymmetry but increased considerably at 10 mm and continued to increase with greater degrees of asymmetry. The highest-rated images showed perfect bilateral symmetry, whereas the lowest-rated images showed significant degrees of mandibular and chin asymmetry.

The influence of craniofacial to standing height proportion on perceived attractiveness

An idealised male image, based on Vitruvian Man, was created. The craniofacial height was altered from a proportion of 1/6 to 1/10 of standing height, creating 10 images shown in random order to 89 observers (74 lay people; 15 clinicians), who ranked the images from the most to the least attractive. The main outcome was the preference ranks of image attractiveness given by the observers. Linear regressions were used to assess what influences the choice for the most and the least attractive images, followed by a multivariate rank ordinal logistic regression to test the influence of age, gender, ethnicity and professional status of the observer. A craniofacial height to standing height proportion of 1/7.5 was perceived as the most attractive (36%), followed by a proportion of 1/8 (26%). The images chosen as most attractive by more than 10% of observers had a mean proportion of 1/7.8(min=1/7; max=1/8.5). The images perceived as most unattractive had a proportion of 1/6 and 1/10. The choice of images was not influenced by the age, gender, ethnicity or professional status of the observers. The ideal craniofacial height to standing height proportion is in the range 1/7 to 1/8.5. This finding should be considered when planning treatment to alter craniofacial or facial height.

Canine substitution for missing maxillary lateral incisors: The influence of canine morphology, size, and shade on perceptions of smile attractiveness

INTRODUCTION This study was conducted to determine whether variations in the morphology, size, or shade of maxillary canines would influence perceptions of smile attractiveness in patients with canines substituted for missing maxillary lateral incisors. METHODS A smiling photograph of a hypodontia patient who had had orthodontic space closure with maxillary canines replacing the lateral incisors was digitally modified to create a bilaterally symmetrical image. Four groups of images were created, digitally altering canine gingival height, crown tip height, canine width, and canine shade. Three groups of judges (40 orthodontists, 40 dentists, and 40 laypeople) ranked the images for smile attractiveness, also scoring the most and the least attractive of each of the 4 groups, and the most and least attractive of all images. RESULTS Canine gingival height was the most attractive 0.5 mm below the gingival margin of the maxillary central incisor and progressively less attractive with increasing gingival height. Increasing canine width, increased canine tip height, and pointed canines were perceived to be unattractive. Brighter than normal shades of canines were preferred to darker shades. Narrow canine crowns were most frequently ranked as the most attractive overall, 1.5 mm narrower was preferred by the orthodontists and dentists, and 3.0 mm narrower was preferred by the laypeople. All 3 groups ranked the darkest image, 20 times darker than the original, most frequently as the least attractive image overall. There was good general agreement between orthodontists, dentists, and laypeople for all 4 parameters of smile attractiveness, although laypeople demonstrated greater intragroup variations. CONCLUSIONS The morphology, size, and shade of the maxillary canine in patients having orthodontic space closure and lateral incisor substitution can have a marked effect on perceived smile attractiveness.

Cost-effectiveness of counselling, graded-exercise and usual care for chronic fatigue: evidence from a randomised trial in primary care

BackgroundFatigue is common and has been shown to result in high economic costs to society. The aim of this study is to compare the cost-effectiveness of two active therapies, graded-exercise (GET) and counselling (COUN) with usual care plus a self-help booklet (BUC) for people presenting with chronic fatigue.MethodsA randomised controlled trial was conducted with participants consulting for fatigue of over three months’ duration recruited from 31 general practices in South East England and allocated to one of three arms. Outcomes and use of services were assessed at 6-month follow-up. The main outcome measure used in the economic evaluation was clinically significant improvements in fatigue, measured using the Chalder fatigue scale. Cost-effectiveness was assessed using the net-benefit approach and cost-effectiveness acceptability curves.ResultsFull economic and outcome data at six months were available for 163 participants; GET = 51, COUN = 58 and BUC = 54. Those receiving the active therapies (GET and COUN) had more contacts with care professionals and therefore higher costs, these differences being statistically significant. COUN was more expensive and less effective than the other two therapies. The incremental cost-effectiveness ratio of GET compared to BUC was equal to £987 per unit of clinically significant improvement. However, there was much uncertainty around this result.ConclusionThis study does not provide a clear recommendation about which therapeutic option to adopt, based on efficiency, for patients with chronic fatigue. It suggests that COUN is not cost-effective, but it is unclear whether GET represents value for money compared to BUC.Clinical Trial Registration number at ISRCTN register: 72136156

How does variation in lower anterior face height influence perceived attractiveness? A quantitative investigation

Objective The purpose of this investigation was to undertake an objective and quantitative evaluation of how severity of lower anterior face height (LAFH) variations influences perceived attractiveness. Design Cross-sectional study Setting St Georges Hospital, London, UK Participants and methods The LAFH of an idealized male and female frontal facial image were altered in 2·5 mm increments from −20 to 20 mm (male images) and from −10 to 20 mm (female images), in order to represent reduction and increase in height of this region. These images were rated by a pre-selected group of pre-treatment orthognathic patients (n = 75), clinicians (n = 35) and laypersons (n = 75). Outcome measures Ratings on a seven-point Likert scale. Results With an increase in LAFH, desire for surgery became significant at 15–16 mm for male faces and 13–14 mm for female faces. With a reduction in LAFH, desire for surgery became significant at −14 to −17 mm for male faces; a smaller reduction of −6 to −8 mm led to a significant desire for surgery for female faces. Conclusions The classical vertical facial trisection canon of upper face height as one-third (33·3%), midface height as one-third (33·3%) and LAFH as one-third (33·3%) of total anterior face height may be used as an ‘ideal’ proportional ratio. Mild LAFH variations were largely acceptable. In terms of the percentage LAFH to total anterior face height (TAFH) and anterior face height (AFH), observers did not desire surgery for LAFH variations of 25–42% of TAFH (40–66% of AFH) for male faces, and 28–42% of TAFH (45–66% of AFH) for female faces.

On-line preparatory information for children and their families undergoing dental extractions under general anesthesia: A phase III randomized controlled trial

Family‐centered interactive on‐line games are increasingly popular in healthcare, but their effectiveness for preoperative preparation needs further research. www.scottga.org is the new on‐line version of a proven nonweb‐based game for children and parents/caregivers.