Tomography In Young Adults Research Articles

Skeletal effects of monocortical and bicortical mini-implant anchorage on maxillary expansion using cone-beam computed tomography in young adults

This study aimed to evaluate and compare the skeletal effects of monocortical andbicortical mini-implant anchorage on maxillary skeletal expansion (MSE) using cone-beam computed tomography in young adults. The sample comprised 48 patients (aged 19.4±3.3years; 19 male, 29 female) treated with maxillary skeletal expander and was divided into 3 groups according to insertion pattern of mini-implants used. G1, 4-all-bicortical penetration (n=17); G2, 2-rear-bicortical penetration (n=17); G3, non-4-bicortical penetration (n=14). Cone-beam computed tomography scans were taken beforetreatment and 3months after activation. The transverse width of maxilla, nasal bone, lateral pterygoid plate, zygomatic bone, and temporal bone increased similarly in G1 and G2. Contrarily, G3 produced less skeletal expansion, having no effects on the temporal bone. Significant increases in width were seen in all 3 groups regarding transverse dentolinear measurements. A triangular expansion pattern was also observed, but G1 and G2 showed more parallel expansion than G3. In addition, G1 and G2 showed less inclination of anchorage teeth compared with G3. The loss of vertical alveolar bone, although only in a small amount, was observed in all groups. MSE with non-4-bicortical penetration produced fewer orthopedic effects and more unwanted dentoalveolar side effects, whereas MSE with 2-rear-bicortical and 4-all-bicortical penetration showed similar skeletal effects, which means that 2-rear-bicortical penetrating mini-implants were critical to skeletal expansion.

Corticotomy-assisted slow maxillary expansion with bone allograft assessed with cone beam computed tomography in young adults

Introduction: There is low evidence regarding the effect of slow palatal expansion in the treatment of bilateral posterior cross-bite. In adults the treatment had always been directed to surgical maxillary expansion. Therefore, this study aimed at evaluating corticotomy-assisted slow palatal expansion using cone beam computed tomography (CBCT). Subjects and Methods: The study included six females, 19-20 years old, with bilateral posterior cross-bite and Class III malocclusion. CBCT was taken pretreatment (T0), immediately post-expansion (T1) and three months following the end of orthodontic treatment (T2). Four banded quad-helix appliance assisted with buccal corticotomy and bone allograft was used for expansion. The expansion was activated every two months. Fixed orthodontic appliance was performed to continue the treatment of the cases. CBCT was used to measure and record amount of expansion and tipping of premolars and first molars. The bone fenestrations were also recorded as scores. Data were statistically analyzed. Results: The bilateral posterior cross-bite was treated in 8.5 months. The amount of expansion increased significantly from T0-T1; 5.58±0.77mm, yet it was non-significant from T1-T2; 1.16±0.34mm. There was a significant increase in mean tipping angle from T0-T1 without a significant increase from T1-T2. Regarding buccal bone fenestrations, there was a significant increase from T1-T2 (1.59±1.19,1.79±1.18mm respectively). An inverse correlation was found between bone fenestration and cervical and middle buccal cortical bone thicknesses at T1 and T2. Conclusions: Corticotomy-assisted expansion with quad-helix was an efficient treatment modality of bilateral posterior cross-bite in young adults. Moderate bone fenestration was recorded at the end of expansion.

Abstract 31: Prediction of coronary artery and abdominal aortic calcium in middle-aged adults using the Pathobiological Determinants of Atherosclerosis in Youth (PDAY) risk score: the CARDIA study

Background: Risk scores to predict coronary and abdominal atherosclerosis have been developed from autopsy specimens from the right coronary artery and descending aorta and risk factors measured post-mortem in the Pathobiological Determinants of Atherosclerosis in Youth Study (PDAY), cohort aged 15-34 years. While the PDAY risk score predicts coronary artery calcium (CAC) up to 15 years before its assessment in Coronary Artery Risk Development in Young Adults (CARDIA), the clinical validity at 25 years follow up and of the abdominal score to predict abdominal aortic calcium (AAC) has not been tested. Objectives: To test the hypotheses: 1) PDAY risk scores at CARDIA baseline (cohort aged 18-30 years) predict CAC and abdominal aortic calcium (AAC) at year 25 better than PDAY risk scores measured at subsequent time points. 2) Change in risk over time will improve associations in Aim 1. Methods: The CARDIA study assessed CAC and AAC by computed tomography in young adults participating at year 25. The PDAY risk score was calculated from risk factors measured at the CARDIA examinations at years 0 (cohort aged 18-30 years), 5, 10, 15 and 25 (age 43-55 years). Results: Age and gender independent PDAY risk scores increased from CARDIA year 0 to year 25 (coronary from 1.80 to 4.95, abdomen from 1.88 to 3.18). Prevalence of any CAC was 28% and AAC was 53%. For a one point increase in risk score, baseline risk predicted CAC and AAC better than year 25 risk; change in risk improved the prediction further (Table). C-statistics for CAC prediction were higher at year 0 but similar at years 0 and 25 for AAC. Further analyses using PDAY scores calculated at 5 year intervals prior to the CT scan confirmed that CAC at baseline and AAC at year 5 had the highest Odds Ratios for a one point increase in score (AAC year 5 Odds Ratio 1.35 (1.30-1.41)). Conclusions: PDAY risk scores, applied to living adults in the CARDIA study, predicted CAC and AAC in 43-55 year old adults; including change in risk slightly improves model performance.

Prediction of Coronary Artery Calcium in Young Adults Using the Pathobiological Determinants of Atherosclerosis in Youth (PDAY) Risk Score

Using data from autopsied young people aged 15 to 34 years, the Pathobiological Determinants of Atherosclerosis in Youth (PDAY) study developed a risk score based on age, sex, smoking status, high-density lipoprotein and non-high-density lipoprotein cholesterol levels, and the presence of obesity, hyperglycemia, and hypertension to predict advanced coronary artery atherosclerosis. The Coronary Artery Risk Development in Young Adults (CARDIA) study assessed coronary artery calcium (CAC) by computed tomography in young adults participating in the 15-year examination. The PDAY risk score was calculated from risk factors measured at the CARDIA examinations at years 0, 5, 10, and 15. Odds ratios for amount of CAC (6 ordinal categories) for a 1-point increase in risk score computed from the modifiable risk factors ranged from 1.10 to 1.16 (all statistically significant). Odds ratios for presence of any amount of CAC ranged from 1.09 to 1.15 (all statistically significant), with the highest odds ratio for the risk score at year 0. An increase in risk score between years 0 and 15 increased the odds of CAC, and a decrease in risk score decreased the odds of CAC. A positive family history of cardiovascular disease increased the odds of CAC. The c statistics ranged from 0.752 to 0.770, with the highest discrimination based on the year 0 revised PDAY risk score that included family history and increased the points for the sex differential. The PDAY risk score predicts CAC up to 15 years before its assessment, and risk score change during 15 years affects the risk of CAC.

Delineation of prevalence and risk factors for early coronary artery disease by electron beam computed tomography in young adults with type 1 diabetes.

Type 1 diabetes increases the risk for coronary artery disease (CAD), but limited information is available regarding the early natural history of this process. Electron beam tomography (EBT) can measure coronary artery calcification (CAC), an early marker for CAD. This study was designed to assess the prevalence and risk factors for CAC in young adults with established type 1 diabetes. A total of 101 subjects aged 17-28 years with type 1 diabetes of over 5 years' duration and no history of heart disease underwent cardiac EBT with calcium scoring. Medical histories were obtained and physical examinations were conducted to document the presence of cardiac risk factors as well as evidence of microvasculopathy and diabetic arthropathy. Laboratory evaluation included measurement of fasting lipoproteins, homocysteine concentration, lipoprotein(a) [Lp(a)], urinary microalbumin, and HbA(1c). Contingency table analysis was used to assess bivariate relationships. Logistic regression was employed to construct a parsimonious model of independent risk factors. Eleven subjects (10.9%) had CAC. Smokers were nearly five times more likely than nonsmokers to have CAC (P = 0.03). In addition, each 0.36-mm/l increment of Lp(a) was associated with a 10% increased risk for CAC (P = 0.05) after controlling for potentially confounding factors. There was no association of other CAD or diabetes risk factors studied with CAC. The prevalence of early CAD as evidenced by CAC in young adults with type 1 diabetes is significant. Smoking and Lp(a) levels independently predict the presence of CAC. Additional study is necessary to delineate the natural history of CAC and the role of risk factor modification to prevent progression of CAD in this high-risk population.