Bone reinforcement lines and osteoporosis: an overlooked trait useful for physical anthropologists?

This study aims to evaluate the efficacy of humerus cortical thickness on coronal T1-weighted images of the humerus in distinguishing patients with normal vs. abnormal bone mineral density (BMD). Patients (n:138) with shoulder magnetic resonance imaging (MRI) and dual-energy x-ray absorptiometry (DXA) scans were evaluated. Patients were grouped into normal and low BMD (osteopenia and osteoporosis) according to DXA. An average cortical bone thickness (CBTavg) and gauge cortical bone thickness (CBTg) were calculated from the proximal humerus on coronal T1W MRI. Sensitivity and specificity for the prediction of osteoporosis were determined for several cortical bone thickness thresholds. Proximal humerus average cortical bone thickness measurements strongly correlated with DXA femur and lumbar scores (p < 0.01). Gauge cortical thickness measurements also correlated with DXA femur and lumbar scores (p < 0.01). Average cortical bone thickness measurement of 4.52 mm was determined to be a potential marker for predicting osteoporosis, with a sensitivity of 92.3% and a specificity of 84.9%. Average cortical bone thickness measurements obtained from shoulder MRI are correlated with DXA. It appears to be effective in differentiating patients with normal and abnormal BMD and may help to opportunistically predict patients with osteoporosis in a rapid, simple and practical way, potentially guiding further diagnostic assessments.

There have been several studies reporting the effect of hypercholesterolemia on cortical thickness, but it remains a controversy. Some studies suggest that hypercholesterolemia can decrease osteoblast activity and increase osteoclast activity. Meanwhile other studies suggest that hypercholesterolemia is a protective factor of osteoporosis. Therefore, it is necessary to conduct a study to determine the effect of hypercholesterolemia on cortical bone thickness. Method: This study used 8 rats (Rattus norvegicus) that were divided into 2 groups, including control group (K0) that was given standard diet and experimental group (K1) that was given high fat diet for 28 days and all were executed to obtain the femur bone. The cortical bone thickness was measured by using Optilab Viewer and Optilab Image Raster software. Result: The data analysis was conducted using independent t-test. A p value of &lt;0.05 is considered significant. The results showed that hypercholesterolemia had significant effect on cortical bone thickness. The average cortical bone thickness in the control group was 146.92 µm whereas in the experimental group was 124.53 µm, the mean difference between the two groups was 22.39 µm. There was a 6% decrease of cortical bone thickness. In conclusion, hypercholesterolemia can decrease cortical bone thickness of wistar rats (Rattus norvegicus).

There have been several studies reporting the effect of hypercholesterolemia on cortical thickness, but it remains a controversy. Some studies suggest that hypercholesterolemia can decrease osteoblast activity and increase osteoclast activity. Meanwhile other studies suggest that hypercholesterolemia is a protective factor of osteoporosis. Therefore, it is necessary to conduct a study to determine the effect of hypercholesterolemia on cortical bone thickness. Method: This study used 8 rats (Rattus norvegicus) that were divided into 2 groups, including control group (K0) that was given standard diet and experimental group (K1) that was given high fat diet for 28 days and all were executed to obtain the femur bone. The cortical bone thickness was measured by using Optilab Viewer and Optilab Image Raster software. Result: The data analysis was conducted using independent t-test. A p value of &lt;0.05 is considered significant. The results showed that hypercholesterolemia had significant effect on cortical bone thickness. The average cortical bone thickness in the control group was 146.92 µm whereas in the experimental group was 124.53 µm, the mean difference between the two groups was 22.39 µm. There was a 6% decrease of cortical bone thickness. In conclusion, hypercholesterolemia can decrease cortical bone thickness of wistar rats (Rattus norvegicus).

Proximal humerus cortical bone thickness correlates with bone mineral density and can clinically rule out osteoporosis

A critical component of treatment planning in dental implant therapy is the amount of available bone. Thick cortical plates have been the primary way to achieve primary implant stability. However, information about cortical bone thickness in various regions of the maxilla and mandible is largely missing. Hence, it was the purpose of this cadaver study to determine an average cortical bone thickness in different tooth locations. To determine the average thickness of buccal and lingual plates, 28 cadaver heads (68% male and 32% female) with an average age of 73.1 years were measured at various locations correlating to molar (M), premolar (PM), and anterior (A) regions. Edentulous and dentate regions also were recorded. Average buccal cortical thicknesses were 1.69 mm (M), 1.43 mm (PM), and 1.04 mm (A) in the edentulous maxilla; 2.06 mm (M), 1.78 mm (PM), and 1.36 mm (A) in the edentulous mandible; 2.23 mm (M), 1.62 mm (PM), and 1.59 mm (A) in the dentate maxilla; and 1.98 mm (M), 1.20 mm (PM), and 0.99 mm (A) in the dentate mandible. Average lingual cortical thicknesses were 2.06 mm (M), 1.60 mm (PM), and 1.36 mm (A) in the edentulous maxilla; 2.39 mm (M), 1.88 mm (PM), and 1.66 mm (A) in the edentulous mandible; 2.35 mm (M), 2.0 mm (PM), and 1.95 mm (A) in the dentate maxilla; and 2.51 mm (M), 1.92 mm (PM), and 1.24 mm (A) in the dentate mandible. The average cortical thickness of the buccal plates ranged from 1.0 to 2.1 mm in the edentulous maxilla and mandible, with the thinnest area in the anterior maxilla and the thickest area in the posterior mandible. The buccal plate of the dentate maxilla and mandible ranged from 1.6 to 2.2 mm in thickness, with the thinnest area in the lower anterior region and the thickest area in the upper posterior region.

BackgroundBisphosphonate (BP) has the ability to thicken the cortical bone. In addition, it has been reported that the cortical bone thickened by BP has relation to the medication-related osteonecrosis of the jaw (MRONJ). Therefore, the objective of this article is to analyze the ratio as well as thickness of cortical bone in the mandible using computed tomography (CT) and to evaluate it as the predictive factor of MRONJ.MethodsThe thickness of the cortical bone was measured on a paraxial view of the CT showing the mental foramen in 95 patients: 33 patients with MRONJ (3 males, 30 females), 30 patients taking BP without MRONJ (2 males, 28 females), and 32 controls (9 males, 28 females). Also, the ratios of the cortical bone to the total bone were obtained using the measured values. Based on these results, we compared the difference of mandibular cortical bone ratio between the three groups.ResultsThe average cortical bone thickness was measured as 3.81 mm in patients with MRONJ, 3.39 mm in patients taking BP without MRONJ, and 3.23 mm in controls. There was only a significant difference between patients with MRONJ and controls (P < 0.05). On the other hand, the average mandibular cortical bone ratio was measured as 37.9% in patients with MRONJ, 27.9% in patients taking BP without MRONJ, and 23.3% in controls. There was a significant difference between all groups (P < 0.05).ConclusionThe mandibular cortical bone ratio is large in order of patients with MRONJ, patients taking BP without MRONJ, and controls. This result suggests that the mandibular cortical bone ratio would be very useful to predict the development of MRONJ.

Objective: To evaluate the bone thickness at infrazygomatic crest as a site for orthodontic mini-implant insertion. Materials and methods: Fifty CBCT images were collected from a CBCT centre. Slice data were analysed and measurements were done at three sites. The measurements were made at three different angles. These measurements were repeated both on the right and left sides of IZC 6 AND IZC 7. The data were analysed using two sample t test and Mann Whitney U test. Results: The maximum bone thickness was evident at IZC 7 region (7.88mm) and in IZC 6 the bone thickness was (7.0 mm). The bone thickness measured at an angulation of 150 from cemento enamel junction showed increased bone thickness available at infrazygomatic region irrespective of roots. As the angulation increased bone thickness decreased. There was no difference between right and left side. Conclusion: The cortical bone thickness between right and left side of IZC 6 and IZC 7 was similar and statistically insignificant. The thickness at mesiobuccal root of IZC 6 was less when compared to IZC 7. Similarly, at the distobuccal root. Hence the ideal site would be IZC 7or our population without compromising the primary stability. The result of this study indicated that the average cortical bone thickness at IZC 7 was greater than IZC 6. The mean thickness at IZC 7 (7.88 mm) but at IZC 6 (7 mm).

Here we present detailed regional bone thickness and cross-sectional measurements from full adult ribs using high resolution CT scans processed with a cortical bone mapping technique. Sixth ribs from 33 subjects ranging from 24 to 99years of age were used to produce average cortical bone thickness maps and to provide average±1SD corridors for expected cross-section properties (cross-sectional areas and inertial moments) as a function of rib length. Results obtained from CT data were validated at specific rib locations using direct measurements from cut sections. Individual thickness measurements from CT had an accuracy (mean error) and precision (SD error) of -0.013±0.167mm (R2 coefficient of determination of 0.84). CT-based measurement errors for rib cross-sectional geometry were -0.1±13.1% (cortical bone cross-sectional area) and 4.7±1.8% (total cross-sectional area). Rib cortical bone thickness maps show the expected regional variation across a typical rib's surface. The local mid-rib maxima in cortical thickness along the pleural rib aspect ranged from range 0.9 to 2.6mm across the study population with an average map maximum of 1.4mm. Along the cutaneous aspect, rib cortical bone thickness ranged from 0.7 to 1.9mm with an average map thickness of 0.9mm. Average cross-sectional properties show a steady reduction in total cortical bone area from 10% along the rib's length through to the sternal end, whereas overall cross-sectional area remains relatively constant along the majority of the rib's length before rising steeply towards the sternal end. On average, male ribs contained more cortical bone within a given cross-section than was seen for female ribs. Importantly, however, this difference was driven by male ribs having larger overall cross-sectional areas, rather than by sex differences in the bone thickness observed at specific local cortex sites. The cortical bone thickness results here can be used directly to improve the accuracy of current human body and rib models. Furthermore, the measurement corridors obtained from adult subjects across a wide age range can be used to validate future measurements from more widely available image sources such as clinical CT where gold standard reference measures (e.g. such as direct measurements obtained from cut sections) are otherwise unobtainable.

The risk of proximal humerus fractures increases with age and deterioration of bone quality over time, and the treatment of these injuries may be clinically challenging.The aim of this study was to analyse the relationship between local bone quality and the morphology of proximal humerus fractures. We conducted a retrospective study of 187 patients diagnosed with proximal humerus fractures. X-ray images of all patients were analysed, and on this basis, bone quality was assessed, using the Deltoid Tuberosity Index (DTI), average cortical bone thickness (CBTavg) and the Tingart measurement. The type of fracture was classified according to Neer's and Association for Osteosynthesis (AO) classifications. Moreover, the caput-collum-diaphyseal (CCD) angle was measured and the relationships between valgus or varus fractures and the DTI, CBTAVG and Tingart parameters were investigated in all patients. Using the Neer classification, the most common fracture type was type 3, found in 90 patients (48.1%). A total of 51 patients (27.3%) sustained an AO B1 fracture. Significantly lower mean DTI values were noted in patients with a Neer 4 fracture compared to those with Neer 3 (p = 0.02) and Neer 2 fractures (p = 0.03). Moreover, significantly higher mean DTI (p &lt;0.00) and CBTAVG (p &lt;0.025) values were noted in the group of patients with valgus fractures (CCD&gt; 140º). 1. In the group of patients diagnosed with a four-part fracture according to Neer, bone quality assessed using the Deltoid Tuberosity Index was significantly worse than in two- and three-part fractures. 2. Significantly higher bone quality, assessed on the basis of the DTI and CBTAVG indices, was observed among patients with valgus fractures compared to those with varus fractures.

Anterior buccal mandibular depression: A descriptive study of CT findings

Osteoporosis can affect the surgical outcomes of proximal humeral fractures in older people. Recently, the cortical bone thickness of the proximal humerus on plain radiograph has been proposed to reflect local osteoporosis of the proximal humerus; however, its effect on the surgical outcome of proximal humeral fractures remains unclear. The purpose of this study is to investigate the influence of cortical bone thickness on postoperative radiographic outcomes after osteosynthesis for proximal humeral fractures. We retrospectively identified 190 patients (≥50years) who underwent osteosynthesis with an intramedullary nail or plate for proximal humeral fractures. The patients were categorized into 2 groups according to the cut-off value of an average proximal humerus cortical bone thickness of 6mm on plain radiographs: patients with and without local osteoporosis. After propensity score matching, we compared the incidence of postoperative radiographic complications between the 2 groups. We also performed subgroup analyses of outcomes in a subgroup of patients who underwent intramedullary nailing and those who underwent plate fixation. Propensity score matching yielded 60 patients in each group. No significant difference in complication rates was observed between the 2 groups. However, in the intramedullary nailing subgroup, the incidence of reduction loss was significantly higher in patients with local osteoporosis than in those without local osteoporosis (51.7% vs 14.3%, P = .002). The proximal humeral cortical bone thickness had no significant effect on the overall radiographic outcome; however, reduction loss after intramedullary nailing was susceptible to local osteoporosis of the proximal humerus. Our study suggests that plate fixation is advantageous in preventing postoperative reduction loss in patients with lower cortical bone thickness.

Assessment of the cortical bone thickness using ultrasonic guided waves: Modelling and in vitro study

Objective:To investigate how associations between education and brain structure in older age were affected by adjusting for IQ measured at age 11.Methods:We analyzed years of full-time education and measures from an MRI brain scan at age 73 in 617 community-dwelling adults born in 1936. In addition to average and vertex-wise cortical thickness, we measured total brain atrophy and white matter tract fractional anisotropy. Associations between brain structure and education were tested, covarying for sex and vascular health; a second model also covaried for age 11 IQ.Results:The significant relationship between education and average cortical thickness (β = 0.124, p = 0.004) was reduced by 23% when age 11 IQ was included (β = 0.096, p = 0.041). Initial associations between longer education and greater vertex-wise cortical thickness were significant in bilateral temporal, medial-frontal, parietal, sensory, and motor cortices. Accounting for childhood intelligence reduced the number of significant vertices by >90%; only bilateral anterior temporal associations remained. Neither education nor age 11 IQ was significantly associated with total brain atrophy or tract-averaged fractional anisotropy.Conclusions:The association between years of education and brain structure ≈60 years later was restricted to cortical thickness in this sample; however, the previously reported associations between longer education and a thicker cortex are likely to be overestimates in terms of both magnitude and distribution. This finding has implications for understanding, and possibly ameliorating, life-course brain health.

Cortical thickness is a highly heritable structural brain measurement, and reduced thickness has been associated with schizophrenia, bipolar disorder, and decreased cognitive performance among healthy control individuals. Identifying genes that contribute to variation in cortical thickness provides a means to elucidate some of the biological mechanisms underlying these diseases and general cognitive abilities. To identify common genetic variants that affect cortical thickness in patients with schizophrenia, patients with bipolar disorder, and controls and to test these variants for association with cognitive performance. A total of 597 198 single-nucleotide polymorphisms were tested for association with average cortical thickness in a genome-wide association study. Significantly associated single-nucleotide polymorphisms were tested for their effect on several measures of cognitive performance. Four major hospitals in Oslo, Norway. A total of 1054 case individuals and controls were analyzed in the genome-wide association study and follow-up cognitive study. The genome-wide association study included controls (n = 181) and individuals with DSM-IV -diagnosed schizophrenia spectrum disorder (n = 94), bipolar spectrum disorder (n = 97), and other psychotic and affective disorders (n = 49). Cortical thickness measured with magnetic resonance imaging and cognitive performance as assessed by several neuropsychological tests. Two closely linked genetic variants (rs4906844 and rs11633924) within the Prader-Willi and Angelman syndrome region on chromosome 15q12 showed a genome-wide significant association (P = 1.1 x 10(-8) with average cortical thickness and modest association with cognitive performance (permuted P = .03) specifically among patients diagnosed as having schizophrenia. This genome-wide association study identifies a common genetic variant that contributes to the heritable reduction of cortical thickness in schizophrenia. These results highlight the usefulness of cortical thickness as an intermediate phenotype for neuropsychiatric diseases. Future independent replication studies are required to confirm these findings.

Cortical bone thickness plays an important role in the primary stability of miniscrews. The purpose of this study was to evaluate the buccal cortical bone thickness in adolescent subjects with different vertical skeletal patterns using cone-beam computed tomography (CBCT). We examined the CBCT images of 75patients (30males, 45females; mean age 16.5years; range 15.3-17.7years) in the present study. High-, average- and low-angle subgroups were generated according to SN-GoMe angle. On volumetric images, we measured the buccal cortical bone thickness from canine to the second molar teeth at heights of 5, 7 and 9mm from cemento-enamel junction (CEJ). For statistical evaluation, the Wilcoxon signed rank, Kruskal-Wallis and Tukey HSD tests were applied at the p < 0.05 level. Buccal cortical bone was thickest in the low-angle group. We observed statistically significant differences in the maxilla between the high- and low-angle groups at all levels. In the mandible, we noted statistically significant differences between high-angle and low-angle groups in the canine-first premolar regions at heights of 5 and 7mm, and in the second premolar-first molar region at 7mm height from CEJ. Significant differences were also present between the first and second premolars at heights of 7 and 9mm. Average cortical bone thickness ranged from 1.10-1.37mm in the maxilla and 1.20-3.28mm in the mandible for all groups. Buccal cortical bone thickness in adolescents varied in different vertical skeletal patterns and was greater in the mandible than in the maxilla, with the distance increasing from the CEJ to the apex. As the buccal cortical bone is thinner in high-angle patients, patient-specific measures should be taken when performing miniscrew treatment.