Changes In Bone Density Research Articles

Horizontal Bone Augmentation With Autogenous and Collagenated Xenogeneic Bone Blocks: A Split-Mouth Prospective Clinical, Tomographic, and Histological Pilot Study.

The aim of this study was to compare the clinical, tomographic, and histological performance of collagenated xenogeneic bone blocks (CXBB) in horizontal bone augmentations for implant placement. Five patients with an absence of the 4 upper incisors and an HAC 3 horizontal bone defect, with a remaining of 3 to 5 mm, underwent a bone-grafting procedure with CXBB (test group [TG], n = 5) and autogenous graft (control group [CG], n = 5), with one type of graft used on the right side and other type on the left side. Changes in bone thickness and density (tomographic evaluation), levels of complications (clinically), and distribution pattern between mineralized and nonmineralized tissue (histomorphometrically) were analyzed. Tomographic analysis showed a horizontal bone increase of 4.25 ± 0.78 mm in the TG and 3.08 ± 0.8 mm in the CG between baseline and 8 months postoperatively (P < .05). The horizontal loss between the day of installation of the blocks and 8 months postoperatively was 1.02 ± 0.39 mm for the TG and 1.10 ± 0.71 mm for the CG (P > .05). With regard to bone density, the TG blocks right after installation had 440.2 ± 89.15 HU, and after 8 months, the region reached 730.7 ± 130.98 HU, representing an increase of 29.05%. For the CG blocks, bone density increased from 1052.2 ± 398.35 HU to 1222.5 ± 453.28 HU, representing an increase of 17.03%. The increase in bone density was significantly higher in the TG (P < .05). Clinically, no cases of exposure of the bone blocks and no failure of incorporation were observed. Histomorphometrically, the percentage of mineralized tissue was lower in the TG than in the CG (48.10% ± 2.88% and 53.53% ± 1.05%, respectively), and the opposite was verified for the levels of nonmineralized tissue (52.79% ± 2.88% and 46.47% ± 1.05%, respectively; P < .05). The use of CXBB achieved higher levels of horizontal gain, with lower bone density and lower levels of mineralized tissue when compared with the use of autogenous blocks.

Sex- and site-specific, age-related changes in bone density - a Terry collection study.

As modern populations are living longer, age-related health issues have become more common. One growing concern is the age-related bone density loss that increases the individual's risk for fractures, which unfortunately seems to disproportionately afflict women. These fractures are not only detrimental to the individuals' lives but also come with a great economic burden to the societies. Although age-related bone loss is a normal phenomenon, studies on archaeological individuals have demonstrated that the pattern how this occurs has experienced changes due to our changing lifestyles. Hence, to add to our understanding of secular trends in age-related bone loss, we studied age- and sex-related differences in vertebral and femoral bone densities of a recent past population of late 19th and early 20th century Americans. We used a sample of 114 individuals (55 males, 59 females) from the Robert J. Terry Anatomical Skeletal Collection. Peripheral quantitative computed tomography (pQCT) was used to scan the dry bones. We took one scan from the 4th lumbar vertebra and three scans from the femur. The associations between the age, sex and bone density were analyzed. We were able to detect age-related bone loss in both vertebra and femur. It was observed that men tended to lose more bone density on the vertebra, whereas bone loss in women was more pronounced in the femur. We speculate that differences to modern and earlier archaeological populations are related to the major lifestyle differences between the periods.

Open-source pipeline for automatic segmentation and microstructural analysis of murine knee subchondral bone.

A segmented dataset of μCT scans from 62 knees (healthy and arthritic) from 10-week male C57BL/6 mice was used to train a U-Net type architecture to automate segmentation of the subchondral trabecular bone. These segmentations were used in tandem with the original scans as input for microstructural analysis along with thresholded trabecular bone. Manually and U-Net segmented ROIs were fed into two available pipelines for microstructural analysis: the ITKBoneMorphometry library and CTan (SKYSCAN). Outcome parameters were compared between pipelines, including: bone volume (BV), total volume (TV), BV/TV, trabecular number (TbN), trabecular thickness (TbTh), trabecular separation (TbSp), and bone surface density (BSBV). There was good agreement for all bone measures comparing the manual and U-Net pipelines utilizing ITK (R = 0.88-0.98) and CTAn (R = 0.91-0.98). ITK and CTAn showed good agreement for BV, TV, BV/TV, TbTh and BSBV (R = 0.9-0.98). However, limited agreement was seen between TbN (R = 0.73) and TbSb (R = 0.59) due to methodological differences in how spacing is evaluated. Microstructural parameters generated from manual and automatic segmentations showed high correlation across all measures. Using the CTAn pipeline yielded strong R2 values (0.83-0.96) and very strong agreement based on ICC (0.90-0.98). The ITK pipeline yielded similarly high R2 values (0.91-0.96, except for TbN (0.77)), and ICC values (0.88-0.98). The automated segmentations yield lower average values for BV, TV and BV/TV (ranging from 14 % to 6.3 %), but differences were not found to be influenced by the mean ROI values. This integrated pipeline seamlessly automated both segmentation and quantification of the proximal tibia subchondral bone microstructure. This automated pipeline allows the analysis of large volumes of data, and its open-source nature may enable the standardization of microstructural analysis of trabecular bone across different research groups.

The Efficacy of Strength Exercises for Reducing the Symptoms of Menopause: A Systematic Review.

The aim of this systematic review was to determine whether strength exercises improve the symptoms of menopause and to provide an update on the most recent scientific evidence on the type and regimen of exercise that help reduce the symptoms. An electronic search of scientific databases was performed from 2015 to 2022. Randomized clinical trials that analyzed the effects of strength exercises versus other types of interventions, considering all the outcome measures of interest, were included in this review. We found 5964 potential articles. After applying the selection criteria, we selected 12 of the articles. The studies compared strength exercises versus other therapies or compared strength exercises versus no intervention in one of the groups. The results showed improvements in the strength of the legs and pelvic floor, physical activity, bone density, metabolic and hormonal changes, heart rate and blood pressure and a change in hot flashes. There is evidence that strength exercises can be beneficial for improving strength, physical activity, bone density and hormonal and metabolic levels. In terms of the appropriate type of strength training, the evidence is still unclear given that the same benefits are achieved by various types of exercises.

Long-Term Changes in Bone Density and Bone Metabolism After Gastric Bypass Surgery: a Retrospective Cohort Study.

Patients with severe obesity submitted to Roux-en-Y gastric bypass (RYGB) are at risk of developing long-term hypovitaminosis D and secondary hyperparathyroidism (SHPT) as well as osteometabolic disease. This study aimed to evaluate calcium-vitamin D-PTH axis and bone mineral density (BMD) changes from post-RYGB patients who were followed-up until a median of 5 years. Vitamin D deficiency was defined as 25-hydroxyvitamin D <20 ng/mL and SHPT as PTH >68 pg/mL, in patients with normal serum creatinine and calcium. BMD was estimated by dual-energy X-ray absorptiometry (DXA, g/cm2). We included 127 post-RYGB patients (51±10.6 years, 87.4% self-declared White, 91.3% female, 52.8% postmenopausal). Vitamin D deficiency prevalence was the highest (41.5%) in the second year and the lowest (21.2%) in the third year (p<0.05). SHPT prevalence was 65.4% in the second year and increased to 83.7% in the sixth year (p<0.05). Patients with low BMD in lumbar, femoral neck, and total proximal femur were older and presented menopausal status more frequently than normal BMD group (p<0.05). Older age was a risk marker for altered BMD in femoral neck (OR=1.185; 95% CI 1.118-1.256) and in total proximal femur (OR=1.158; 95% CI 1.066-1.258), both after adjusting for follow-up and excess weight loss. After 5 years, most bariatric patients presented calcium-vitamin D-PTH axis disruption, in which SHPT was more frequent than hypovitaminosis D. Older patients and menopausal women presented higher rates of low BMD, and older age was a risk marker, especially for low BMD in femoral sites.

Changes in bone density in obese children according to the results of radiation diagnostic methods (review)

Changes in bone density in obese children according to the results of radiation diagnostic methods (review)

Global research trends in bone mineral density in children with diabetes: a bibliometric and visualization study

Research on bone density in children with diabetes has attracted increasing attention, and this study aims to investigate the global status and trends in this field.From the Web of Science's Science Citation Index, research papers related to bone density in children with diabetes from 1984-2022 were retrieved. Source data were studied and indexed using bibliometric methods. The visualization study used VOS viewer software for literature coupling, co-authorship, co-citation and co-occurrence analysis to analyze the publication trend of bone density in children with diabetes.A total of 1074 articles were included. Globally, the number of related research interests and publications is increasing every year. The United States contributes the most to global research, receives the most citations, and has the highest h-index. The Journal of Clinical Endocrinology and Metabolism has the highest number of publications.The university of pennsylvania,Childrens hospital of philadelphia,Pennsylvania medicine,Harvard university and university of Sydney are the largest contributors. Research can be divided into four categories: mechanistic research, animal research, clinical trials, and tissue engineering. Mechanism research is expected to be the next hot topic in this field.From the current global research trend, the number of papers on bone density in children with diabetes will continue to increase. The United States is the largest contributor in this area. Much of the effort is devoted to the mechanisms of changes in bone density in children with diabetes, which could be the next hot spot in research.

An in vivo study to assess and compare the angular, linear, and depth deviation as well as the difference in bone density of implants placed using computer-aided design/computer-aided manufacturing fabricated three-dimensional guides versus the implants placed using bone pen kit in maxillary and mandibular ridges.

The aim is to assess and compare angular, linear, and depth deviation and difference in bone density of dental implants placed using computer aided design/computer aided manufacturing (CAD/CAM) fabricated surgical guides versus implants placed using Bone Pen Kit. Till now, no original research exists in the search engines such as Pubmed, Google Scholar, Science Direct, and Research Gate on this kit. In vivo- Randomised control trial. Twenty clinical cases were selected and split into two distinct groups. Group 1 involved the placement of 10 implants using CAD/CAM fabricated three dimensional guides and Group 2 involved the placement of 10 implants using Bone Pen Kit. Four deviation parameters were evaluated, which included: (a) Angular deviation, (b) Linear deviation at implant platform, (c) Linear deviation at implant apex, and (d) Depth deviation and difference in bone density before and after implant placement was also evaluated. SPSS software version 23 was utilized for the analysis of the data. The comparison was made using the Whitney test, and Wilcoxon signed rank test. When comparing angular deviation, the results indicated a statistically significant difference with a P < 0.05. The values observed for angular and linear deviation in Group 2 were significantly greater than those in Group 1. No statistically significant difference in depth and linear deviation was found at the implant platform among the two groups. Bone density before and after implant placement was significantly higher in Group 1. (1) Angular and linear deviation at the apex in Group 2 exhibited higher values in comparison to Group 1, (2) No difference in depth and linear deviation at the implant platform was found among the two groups, and (3) There was no difference in change in bone density among two groups.

Uticaj lokalnih vibracija na mineralnu gustinu kostiju distalne podlaktice

A prolonged, mainly professional, exposure to hand-arm vibration (HAV) may cause a complex chronic disorder of the upper extremities known as Hand-Arm Vibration Syndrome (HAVS). Besides vascular and neurological injuries, such exposure to HAV may cause various bone disorders in the form of cystic changes, exostoses, aseptic necrosis, osteoarthritis, spontaneous fractures and osteoporosis. The objective of this study was to examine whether there were any changes in the bone mineral density in the distal forearm in persons professionally exposed to HAV. In a group of 31 workers professionally exposed to vibrations (29 men and 1 woman) with neurological and/or vascular signs of HAVS, the bone mineral density of the distal part of the radius of both hands was examined by dual X-ray absorptiometry (DXA). The control group consisted of 25 healthy subjects with no history of HAV exposure. Osteopenia was found in 14 subjects (45.16%), which makes a statistically significant difference compared to the control group (p=0.017), where osteopenia was found in 3 subjects (12.0%). Osteoporosis was not found in any of the subjects. Analyzing the value of T score for the dominant (-0.81±0.58 SD) and non-dominant hand (-0.62±0.68SD) in our patients, we found no statistically significant difference in the average T score values of the dominant and non-dominant hand (p=0.269). Changes in bone density at the distal radius are common in persons occupationally exposed to HAV. Distal forearm DXA examination in workers occupationally exposed to HAV can help diagnose HAVS.

Radiological Comparative Study Between Conventional and Nano Hydroxyapatite With Platelet-Rich Fibrin (PRF) Membranes for Their Effects on Alveolar Bone Density.

The entry of the concept of nanotechnologies into the field of biomaterials has improved the results of their use in regenerative therapies based on the principles of tissue engineering, due to its improvement of the physical properties of materials manufactured in this way, so it has become possible to produce particles of hydroxyapatite in nano sizes. This study will evaluate the efficacy of applying nanohydroxyapatite paste and platelet-rich fibrin (PRF) as a barrier membrane in comparison with traditionalhydroxyapatite (a powder consisting of macro-sized particles) and PRF as a barrier membrane in symmetrically extracted alveoli of the mandible. The research sample consisted of 40 lower alveoli (symmetrical) of the extracted teeth. The study samples were divided randomly into two groups. Group 1: A paste of nanohydroxyapatite with PRF as a barrier membrane was applied to one side of the extraction. Group 2: Hydroxyapatite powder with PRF as a barrier membrane was applied to the alveolus from the opposite side of Group 1 (the opposite side of the extraction). Three radiographs were performed by cone beam conventional tomography (CBCT) in three consecutive periods to conduct the radiological study (T0: immediately after extraction and grafting, T1: after three months, T2: after six months). The mean of the radiographic bone density of the hydroxyapatite powder group at time T0 is 824.36 HU with a standard deviation of ±277.29 HU, and at time T1 is 1119.93 HU with a standard deviation of ±306.93 HU, and at time T2 is 1074.14 HUwith a standard deviation of ±223.62 HU, with statistically significant differences when comparing the amount of change in radiographic bone density at time T0 and T1 withP < 0.05, and at time T0 and T2 with P < 0.05, but there were no significant differences when comparing the amount of change in radiographic bone density in T1 and T2 times with P > 0.05. The mean radiographic bone density of the nanohydroxyapatite paste group at time T0 is 629.88 HU with a standard deviation of ±193.64 HU, and at time T1 is 960.67 HU with a standard deviation of ±256.88 HU, and at time T2 is 743.87 HU with a standard deviation of ±180.96 HU, and in the time T0 and T1 with P < 0.05, and in the time T0 and T2 with P < 0.05, and in the time T1 and T2 with P < 0.05. Statistically, significant differences have been found between bone density change T1, T2in the nanohydroxyapatite paste group and bone density change T1, T2in the hydroxyapatite powder group P<0.05, which expresses a greater loss of density in the nanohydroxyapatite group, and thus the resorption of the bone graft and the placement of new bone tissue. Within the limits of our study, the results demonstrated that the use of traditional hydroxyapatite powder and nanohydroxyapatite paste increases the radiographic bone density, nanohydroxyapatite paste has a greater absorbency after 3 months compared with traditional hydroxyapatite powder which helps replace it by natural bone tissue.

Opportunistic optimizing uses CT Imaging for Osteopenia and Osteoporosis screening as early prevention and awareness of bone density changes: Relationship between Hounsfield Unit from CT and T- scores From DXA

Opportunistic optimizing uses CT Imaging for Osteopenia and Osteoporosis screening as early prevention and awareness of bone density changes: Relationship between Hounsfield Unit from CT and T- scores From DXA

Opportunistic optimizing uses CT Imaging for Osteopenia and Osteoporosis screening as early prevention and awareness of bone density changes: Relationship between Hounsfield Unit from CT and T- scores From DXA

Opportunistic optimizing uses CT Imaging for Osteopenia and Osteoporosis screening as early prevention and awareness of bone density changes: Relationship between Hounsfield Unit from CT and T- scores From DXA

Oblique line contrast: A new radiomorphometric index for assessing bone quality in dental panoramic radiographs

The present study was carried out to assess the possible changes in mandibular bone density according to age and gender through dental panoramic radiographs (PAN). More specifically, the region of the mandibular oblique line. Materials & methodsA group of 374 dental patients previously treated in the Ribeirão Preto Dental School (FORP/USP) was included in the study. The complete dental profiling of all the subjects (including PAN images) was previously available in the archive of the same institution. Those subjects were separated into four groups considering age and gender: Group 1–100 young adult men (21.48 ± 3.34 y. o.), Group 2–100 young adult women (20.66 ± 1.52 y. o.), Group 3–87 postmenopausal women (74.07 ± 9.82 y. o.), and Group 4–87 men over 70 years old (75.92 ± 8.71 y. o.). A new index called “W-index” (WI) was proposed for analyzing the possible difference in mandibular bone density. This new index is the ratio between the average pixel value of the image area of the mandibular ramus (AVMR) and the average pixel value of the image area of the mandibular oblique line (AVOL) (WI = AVMR/AVOL). WI was measured for each subject on each PAN and statistical analysis was performed to search how well WI can characterize each study group. ResultsThe largest difference in WI is observed when we compare older subjects (WI 0.73 ± 0.11) with younger subjects (0.89 ± 0.05). WI also varies significantly with gender but in a smaller amount. Mean WI for old women (0.68 ± 0.11) was found lower than for old men (0.77 ± 0.09), and mean WI for young women (0.89 ± 0.05) was also inferior to young men (0.91 ± 0.05). The differences in WI observed in the subject group were tested for a significance level of α = 0,01. We speculate that WI refers to an aspect of bone mineral density. First, the sharp contrast of the mandibular oblique line may signify the loss of mandibular bone mass. And second, it showed to vary significantly with gender and age, but with higher intensity with age. Clinical significanceWI might be used in the future for low bone mineral density risk assessment.

Hounsfield Units measured in low dose CT reliably assess vertebral trabecular bone density changes over two years in axial spondyloarthritis

ObjectivesTo describe low dose Computed Tomography (ldCT) Hounsfield Units (HU) two-year change-from-baseline values (expressing trabecular bone density changes) and analyse their inter-reader reliability per vertebra in radiographic axial spondyloarthritis (r-axSpA). MethodsWe used 49 patients with r-axSpA from the multicentre two-year Sensitive Imaging in Ankylosing Spondylitis (SIAS) study. LdCT HU were independently measured by two trained readers at baseline and two years. Mean (standard deviation, SD) for the change-from-baseline HU values were provided per vertebra by reader. Intraclass correlation coefficients (ICC; absolute agreement, two-way random effect), Bland-Altman plots and smallest detectable change (SDC) were obtained. Percentages of vertebrae in which readers agreed on the direction of change and on change >|SDC| were computed. ResultsOverall, 1,053 (98% of all possible) vertebrae were assessed by each reader both at baseline and two years. Over two years, HU mean change values varied from -23 to 28 and 29 for reader 1 and 2, respectively. Inter-reader reliability of the two-year change-from-baseline values per vertebra was excellent: ICC:0.91-0.99; SDC:6-10; Bland-Altman plots were homoscedastic, with negligible systematic error between readers. Readers agreed on the direction of change in 88-96% and on change >|SDC| in 58-94% of vertebrae, per vertebral level, from C3 to L5. Overall, similar results were obtained across all vertebrae. ConclusionLdCT measurement of HU is a reliable method to assess two-year changes in trabecular bone density at each vertebra from C3-L5. Being reliable across all vertebrae, this methodology can aid the study of trabecular bone density changes over time in r-axSpA, a disease affecting the whole spine.

Bone mass density following developmental exposures to perfluoroalkyl substances (PFAS): a longitudinal cohort study

BackgroundEnvironmental exposures to industrial chemicals, including perfluoroalkyl substances (PFAS), may play a role in bone development and future risk of osteoporosis. However, as prospective evidence is limited, the role of developmental PFAS exposures in bone density changes in childhood is unclear. The objective of this study was to estimate associations between serum-PFAS concentrations measured in infancy and early childhood and areal bone mineral density (aBMD) measured at age 9 years in a birth cohort of children from the Faroe Islands.MethodsWe prospectively measured concentrations of five PFAS in cord serum and serum collected at 18 months, 5 years and 9 years, and conducted whole-body DXA scans at the 9-year clinical visit. Our study included 366 mother-child pairs with DXA scans and at least one PFAS measurement. We estimated covariate-adjusted associations of individual PFAS concentrations with age-, sex- and height-adjusted aBMD z-scores using multivariable regression models and applied formal mediation analysis to estimate the possible impact of by several measures of body composition. We also evaluated whether associations were modified by child sex.ResultsWe found PFAS exposures in childhood to be negatively associated with aBMD z-scores, with the strongest association seen for perfluorononanoic acid (PFNA) at age 5 years. A doubling in age-5 PFNA was associated with a 0.15 decrease in aBMD z-score (95% CI: − 0.26, − 0.039). The PFNA-aBMD association was significantly stronger in males than females, although effect modification by sex was not significant for other PFAS exposures. Results from the mediation analysis suggested that any potential associations between aBMD and 18-month PFAS concentrations may be mediated by total body fat and BMI, although most estimated total effects for PFAS exposures at age 18 months were non-significant. PFAS exposures at age 9 were not associated with age-9 aBMD z-scores.ConclusionsThe PFAS-aBMD associations identified in this and previous studies suggest that bone may be a target tissue for PFAS. Pediatric bone density has been demonstrated to strongly track through young adulthood and possibly beyond; therefore, these prospective results may have important public health implications.

Adjacent Segment Vertebral Body Bone Density Changes as Measured By Hounsfield Units After Lumbar Spine Fusion.

We sought to evaluate Hounsfield units (HU) at the adjacent segment after single-level transforaminal lumbar interbody fusion (TLIF) with preoperative and postoperative computed tomography scans. We performed a retrospective study on a series of patients who underwent L4-5 TLIF, from 2007 to 2017, by 3 spine surgeons at our institution. One-hundred and forty-three total patients were identified, and 41 patients with minimum 1-year follow-up met inclusion criteria. HU values were measured on preoperative and postoperative computed tomography at the adjacent L3 segment and at L1 as a control arm. Lumbar lordosis, pelvic tilt, pelvic incidence, sacral slope, and sagittal vertical axis were also collected preoperatively and postoperatively. Mean preoperative HU value at L3 did not differ from the postoperative value (134.11 ± 47.14 mg/cm3 vs. 141.21 ± 55.14 mg/cm3, P= 0.34). Similarly, the mean preoperative HU value at the L1 control level region of interest did not differ from the postoperative value (150.17 ± 53.91 mg/cm3 vs. 145.78 ± 58.34 mg/cm3, P= 0.634). The interrater reliability of HU measurements was satisfactory with a resulting intraclass correlation coefficient of 0.76. As measured by HU, we did not observe a change in bone density or other signs of adjacent segment disease at the L3 vertebral body 12 months after L4-5 TLIF. Spinopelvic parameters were not shown to be correlated with HU changes.

Midpalatal suture bone repair after miniscrew-assisted rapid palatal expansion in adults

BackgroundMidpalatal suture (MPS) repair in growing patients after RPE has been previously reported. However, differences between young and adult patients for timing and pattern of MPS repair after rapid maxillary expansion are expected. The aim of this study was to evaluate the midpalatal suture repair pattern after miniscrew-assisted rapid palatal expansion (MARPE) in adult patients.Materials and methodsThe study included 21 patients (six males, 15 females) successfully treated with MARPE with a mean initial age of 29.1 years of age (SD = 8.0; range = 20.1–45.1). MPS repair was evaluated using maxillary axial and coronal sections derived from CBCT exams taken 16 months after the expansion (SD = 5.9). Objective and subjective assessments of MPS repair were performed. Objective assessments were performed measuring MPS bone density at anterior, median and posterior region of hard palate. Pre-expansion and post-retention bone density changes were evaluated using paired t tests (p < 0.05). Midpalatal suture bone repair was scored 0 to 3 considering, respectively, the complete absence of bone repair in the MPS, the repair of less than 50% of the MPS, the repair of more than 50% of the MPS and the complete repair of the MPS. Intra- and interexaminer reliability evaluation were assessed using Kappa coefficient.ResultsThe objective evaluation showed a significant higher bone density at the pre-expansion stage in all palatal regions. The reliability of the subjective method was adequate with intra- and interexaminer agreements varying from 0.807 to 0.904. Scores 1, 2 and 3 were found in 19.05%, 38.09% and 42.86% of the sample, respectively. The most common region demonstrating absence of bone repair was the middle third. The anterior third of the midpalatal suture was repaired in all patients.ConclusionsA decreased bone density was observed after the retention period when compared to pre-expansion stage. Most adult patients demonstrated incomplete repair of the midpalatal suture 16 months after MARPE. However, adequate bone repair covering more than half of the hard palate extension was observed in 80.95% of the patients.

Backscatter techniques for ultrasonic bone assessment

Osteoporosis is a bone disease that affects hundreds of millions of people worldwide. The name osteoporosis literally means “porous bone” reflecting the changes in bone density and microstructure that lead to increased risk of fracture. Ultrasonic backscatter techniques have been proposed as a way to detect these changes. Backscatter measurements are performed by propagating ultrasonic pulses into bone and receiving signals returned from the porous interior of the tissue. Numerous backscatter techniques have been developed over the last two decades for ultrasonic bone assessment. This presentation reviews many of those techniques and compares their relative performance in a recent in vivo study using measurements at the femoral neck, a common location for osteoporotic fracture.

Immediate implant placement with simultaneous bone augmentation versus delayed implant placement following alveolar ridge preservation: A clinical and radiographic study

ObjectiveThe present study aimed to evaluate the clinical and radiographic outcomes of immediate implant placement (IIP) with guided bone regeneration (GBR) as compared to delayed implant placement (DIP) following alveolar ridge preservation (ARP) and to identify the potential risk factors influencing these outcomes. MethodologyA total of 56 patients (IIP = 28 vs. DIP = 28) with class I or II bony defects received 56 implants were included. GBR procedure using Bio-Oss® bone substitute mixed with advanced platelet-rich fibrin (A-PRF) and covered by Bio-Gide® membrane and additional A-PRF membrane was performed either simultaneously with the IIP or earlier at the time of ARP in DIP. Clinical and 3-D radiographic analyses of bone level, thickness, and density were performed at three-time intervals (T1, immediately; T2, 6-7 months; and T3, 1.5 to 2 years post-implantation), corresponding to the neck, coronal, middle, and apex of implants. ResultsThe survival rate was 100% in both groups. IIP showed significant favorable outcomes regarding distal marginal bone level (anterior maxilla, T1-T3) and neck and coronal horizontal facial bone thickness (HFBT) (posterior maxilla, T1; and anterior maxilla, T1-T3, respectively) compared to DIP. However, DIP showed significant facial bone density at the neck and coronal parts in the anterior maxilla (T1) and the coronal part in the posterior maxilla (T3). The facial marginal bone level change was positively correlated with HFBT change (P = 0.007), which is negatively correlated with the secondary implant stability (P = 0.019). The implant region (anterior or posterior maxilla) was the only factor affecting on Implant stability quotient value (ISQ) and change in HFBT (P ˂ 0.05). ConclusionOverall, the IIP combined with GBR in the post-extraction sites with pre-implant class I or II bony defects had some favorable outcomes compared to DIP after ARP. However, the clinical outcomes, ISQ value, and changes in bone level, thickness, and density from T1-T3 were comparable.

Stability of dental implants placed in healed bony sites of hyperlipidemic patients

Background: The effect of elevated levels of serum fats ­­-hyperlipidemia- on the long-term implant stability and bone quality has been heavily examined in animal-model studies. This human-based case series is the first clinical study which aimed at clinical and radiographic evaluation of dental implant stability and the changes in bone density in patients with high lipid profile. Materials and Methods: Twelve female patients, each had a single healed bony site which indicated for implantation together with high serum fasting (Low-density lipoprotein) LDL level (≥160 mg/dl) were included in this study. The clinical implant stability values (ISQ) which were measured using the Resonance Frequency Analysis (RFA) method, and CBCT changes were recorded at baseline and six months post-implant insertion. Results: All patients showed implant success after six months. There was a significant increase of implant stability after 6 months from (65.92 ± 6.39 ISQ) to (74.42±6.20 ISQ) (p&lt;0.001).