Evaluation of nasal septal deviation and maxillary bone and nasal airway dimensions and volumes using cone-beam computed tomography in patients with unilateral palatal canine displacement: a retrospective study.

OBJECTIVES: To detect any association between palatally displaced canine (PDC) and nasal septal deviation (NSD), palatal bone thickness and volume, and nasal airway dimensions and volume. MATERIALS AND METHODS: A total of 92 patients were included and subdivided into two groups: group 1, unilateral PDCs (44 patients), and group 2, normally erupted canines (NDCs) (48 subjects). The following variables were measured using cone-beam computed tomography: presence and type of NSD, nasal width, inferior conchae, hard palate and nasal septum thickness, maxillary bone and nasal airway volumes. RESULTS: NSD was detected in 77% and 50% of PDC and NDC subjects, respectively. Within the PDC subjects, significant differences between the displaced and nondisplaced sides were detected. Palate thickness was increased in the canine region and reduced in the molar region. Compared with the control group, PDC subjects had reduced palate thickness and lower nasal airway volume. Two predictors were significant for predicting the odds of PDC occurrence: NSD and maxillary bone volume. CONCLUSIONS: NSD is more frequent in PDC subjects. PDC subjects have reduced palate thickness and decreased nasal airway volume. In the presence of NSD, the odds of developing PDC increase by 3.35 times, and for each one-unit increase in the maxillary bone volume, the odds of developing PDC decrease by 20%.

Technical note: Does scan resolution or downsampling impact the analysis of trabecular bone architecture?

The "gold standard" for the assessment of trabecular bone structure is high-resolution micro-CT. In this technical note, we test the influence of initial scan resolution and post hoc downsampling on the quantitative and qualitative analysis of trabecular bone in a Gorilla tibia. We analyzed trabecular morphology in the right distal tibia of one Gorilla gorilla individual to investigate the impact of variation in voxel size on measured trabecular variables. For each version of the micro-CT volume, trabecular bone was segmented using the medical image analysis method. Holistic morphometric analysis was then used to analyze bone volume (BV/TV), anisotropy (DA), trabecular thickness (Tb.Th), spacing (Tb.Sp), and number (Tb.N). Increasing voxel size during initial scanning was found to have a strong impact on DA and Tb.Th measures, while BV/TV, Tb.Sp, and Tb.N were found to be less sensitive to variations in initial scan resolution. All tested parameters were not substantially influenced by downsampling up to 90 µm resolution. Color maps of BV/TV and DA also retained their distribution up to 90 µm. This study is the first to examine the effect of variation in micro-CT voxel size on the analysis of trabecular bone structure using whole epiphysis approaches. Our results indicate that microstructural variables may be measured for most trabecular parameters up to a voxel size of 90 µm for both scan and downsampled resolutions. Moreover, if only BV/TV, Tb.Sp or Tb.N is measured, even larger voxel sizes might be used without substantially affecting the results.

Clinical-statistical study on oral rehabilitation methods using dental implants.

Background and aims: The development of dental implantology is based on a thorough examination of the interaction of implants with the surrounding tissues, as well as methods of stimulating osteogenesis around implants. The most common approach to restore lost dentition in terms of function and aesthetics is now represented by implants. The objective of our study was to comparatively assess the efficiency of prosthetic treatments performed on implants alone versus on implants in conjunction with abutment teeth. Methods: The study was carried out over seven years (2016-2023), with evaluations at one, two, three, and five years. For this analysis, MedCalc® version 12.5.0.0 (MedCalc® Software, Mariakerke, Belgium) was utilised as the medical statistical software. Results and conclusions: When using dental implants and natural teeth abutments for prosthodontic reconstruction, the failure rates rise approximately 43 times when compared to dental implant rehabilitation; similarly, osteoporosis and diabetes mellitus increase failure rates by 32 and 20 times, respectively. Gingival inflammation is a frequent event (almost 50% frequency) observed during follow-up of patients who had prosthetic restoration using dental implants alone as well as implants and abutment teeth. For both groups, difficulties usually arise two years later.

Effect of interproximal enamel reduction on interradicular bone volume in clear aligner therapy: a three-dimensional cone-beam computed tomography study.

OBJECTIVES: To assess the effect of inter-proximal enamel reduction (IPR) on interradicular bone volume and incisal inclination in patients undergoing clear aligner therapy (CAT). MATERIALS AND METHODS: The study sample consisted of 60 cases which underwent orthodontic CAT, in a private clinic in Dammam, KSA. A total of 120 CBCT scans (60 pre-treatment and 60 post- treatment) were measured using the CS 3D Imaging software to examine bone volume (using height, width, and depth of the interproximal area) and incisal inclination. The corresponding ClinCheck models were collected to determine the amount and locations of interproximal reduction performed. Little's Irregularity Index values were measured using OrthoCAD software. Paired sample t-test was used to address the measurements of bone height, width, depth, bone volume, and inclination of upper and lower incisors before and after IPR. RESULTS: IPR did not affect the upper or lower bone volume except at LR3-2 and UL 2 - 1 where a significant difference between the bone volume with and without IPR was detected (p = 0.02 and p = 0.04 respectively). Upper and lower incisor inclination showed a statistically significant decrease after IPR. There was no correlation between IPR and bone volume difference between upper and lower teeth except at LR3-2 and UL 2 - 1. CONCLUSIONS: IPR had no significant effect on inter-radicular bone volume except at areas of lower right canine-lateral and at areas of upper left central-lateral. There was a positive correlation between the amount of IPR and incisal inclination. CLINICAL RELEVANCE: The current study findings suggest that while IPR has a minimal and localized effect on bone volume in certain areas, it plays a role in adjusting incisal inclination, highlighting its significance in the careful planning of orthodontic treatment using clear aligners.

Assessment of the relationship between the three-dimensional precise location of the mandibular third molar and the volume ratio of the impacted mandibular third molar to the mandibular angle, and the patterns of mandibular angle fracture: A retrospective study.

This study aimed to evaluate the relationship between the precise three-dimensional location of the third molar (M3) and mandibular angle fracture (MAF) patterns and to assess the effect of the volume ratio occupied by M3 in the mandibular angle on fracture patterns. The location of M3 was assessed in 218 patients with MAF using computed tomography reconstruction. The bone volume of the mandibular angle and the bone volume occupied by M3 were measured to calculate the volume ratio of M3 to the mandibular angle (M3/MA). MAF patterns were categorized into simple fracture (Type I), displaced fracture (Type II), and comminuted fracture (Type III) based on fracture severity. The results showed that the location of M3 significantly influenced MAF patterns (vertical position: P = .001; horizontal position: P = .002; angulation: P = .027, respectively) and the volume ratio of M3/MA was significantly higher for Type III fracture than Types I and II (P < .001). Regression analysis showed that the horizontal position and angulation of M3 and the volume ratio of M3/MA were the main predictors for comminuted MAF. A larger volume ratio (odds ratio [OR], 1.201; 95% confidence interval [CI], 1.037-1.391; P < .014), Class III position (OR, 7.978; 95% CI, 1.275-49.910; P < .026), and horizontal angulation (OR, 7.212; 95% CI, 1.028-50.581; P < .047) of the M3 were more prone to comminuted MAF than simple fracture. Our findings indicate that the location of M3 significantly affects MAF patterns, and that M3 may weaken the mandibular angle by occupying more bone space, thereby increasing the risk of a comminuted fracture.

Advantages of customization of osseointegrated implants in transfemoral amputees: a comparative analysis of surgical planning.

BACKGROUND: Commercially available osseointegrated devices for transfemoral amputees are limited in size and thus fail to meet the significant anatomical variability in the femoral medullary canal. This study aimed to develop a customized osseointegrated stem to better accommodate a variety of femoral anatomies in transfemoral amputees than off-the-shelf stems. Customization is expected to enhance cortical bone preservation and increase the stem-bone contact area, which are critical for the long-term stability and success of implants. METHODS: A customized stem (OsteoCustom) was designed based on the statistical shape variability of the medullary canal. The implantability of the OsteoCustom stem was tested via 70 computed tomography (CT) images of human femurs and compared to that of a commercial device (OFI-C) for two different resection levels. The evaluations included the volume of cortical bone removed and the percentage of stem-bone contact area for both resection levels. Statistical significance was analyzed using paired and unpaired t tests. RESULTS: The OsteoCustom stem could be virtually implanted in all 70 femurs, while the OFI-C was unsuitable in 19 cases due to insufficient cortical thickness after implantation, further emphasizing its adaptability to varying anatomical conditions. The OsteoCustom stem preserved a greater volume of cortical bone than did the OFI-C. In fact, 42% less bone was removed at the proximal resection level (3.15 cm³ vs. 5.42 cm³, p ≤ 0.0001), and 33% less at the distal resection level (2.25 cm³ vs. 3.39 cm³, p = 0.003). The stem-bone contact area was also greater for the OsteoCustom stem, particularly at the distal resection level, showing a 20% increase in contact area (52.3% vs. 32.2%, p = 0.002) compared to that of the OFI-C. CONCLUSIONS: The OsteoCustom stem performed better than the commercial stem by preserving more cortical bone and achieving a greater stem-bone contact area, especially at distal resection levels where the shape of the medullary canal exhibits more inter-subject variability. Optimal fit in the distal region is of paramount importance for ensuring the stability of osseointegrated implants. This study highlights the potential benefits of customized osseointegrated stems in accommodating a broader range of femoral anatomies, with enhanced fit in the medullary canal.

A report on the impact of CGF on hard and soft tissues around endo-perio lesion.

There is an increased chance of further periodontal deterioration due to severe intrabony defect. There are s different patho physiologies for perio-endo lesions, ranging from quite basic to rather complicated but to make the right diagnosis, one must be aware of various illness processes also a careful history taking, examination, and the application of specialized tests can help achieve this. Each form of endodontic-periodontal illness has a different prognosis and course of therapy and all kinds of endo-perio lesions require endodontic and periodontal treatments are necessary for primary periodontal disease with subsequent endodontic involvement and real mixed endodontic-periodontal disorders. The severity of the periodontal disease and how well the patient responds to therapy will determine how these situations turn out. Because autologous platelet concentrates are enriched with growth factors, such as concentrated growth factor (CGF), they may enhance surgical outcomes. CGF is inserted into the appropriate intrabony defect following traditional flap debridement. Following flap surgery, the tooth in question had a root canal operation. Volumetric analysis was performed on both groups before to surgery and nine months after the procedure. It has been discovered that the defect area has a much larger bone volume due to the high levels of CGF, a regenerative and reconstructive growth factor that promotes early and high bone fill.

Bone volume and height changes for lateral window sinus floor elevation using two types of deproteinized bovine bone mineral: A retrospective cohort study of 1-4 years.

OBJECTIVE: To compare bone volume and height changes of two types of deproteinized bovine bone mineral (DBBM) for lateral window sinus floor elevation (LSFE) with simultaneous implant placement. MATERIALS AND METHODS: This retrospective cohort study involved 72 patients who underwent LSFE using low-temperature sintered cancellous bone-derived DBBM (C-DBBM) or high-temperature two-step sintered epiphyseal-derived DBBM (E-DBBM). Cone-beam computed tomography (CBCT) was acquired preoperatively, immediately postoperatively, 6 months and 1-4 years post-surgery. Bone volume (BV), apical bone height (ABH), endo-sinus bone gain (ESBG), and crestal bone level (CBL) were evaluated through three-dimensional fitting and superimposition. Linear mixed models (LMM) were employed to analyze factors influencing the reduction of BV (ΔBV) and ESBG (ΔESBG). RESULTS: The E-DBBM group showed no significant change in BV 1-4 years post-surgery, while the C-DBBM group demonstrated a significant reduction (p = .006) with volume stability of 85.86%. Bone height in the E-DBBM group increased at 6 months and subsequently decreased at 1-4 years (p = .003). In the C-DBBM group, it decreased at 6 months (p = .014), then further decreased at 1-4 years (p = .001). ΔESBG was lower in the E-DBBM group than the C-DBBM group from immediate postoperative to 1-4 years (p = .009). LMM showed graft material type was the primary factor influencing ΔBV (p = .026) and ΔESBG (p = .003). CONCLUSIONS: Within the limitations of this study, both types of DBBM could achieve favorable clinical outcomes. E-DBBM demonstrated enhanced stability in maintaining bone volume and height.

Efficacy of the Sausage Technique in Rebuilding the Crestal Buccal Bone Thickness: A Retrospective Analysis.

The goal was to evaluate the efficacy of the sausage technique in reconstructing the crestal buccal bone thickness, focusing on the distribution shape of the regenerated volume. Ten implants were placed in five patients with Cawood-Howell class IV defects. A cone beam computed tomography (CBCT) was executed at T0 (before surgery). Guided bone regeneration (GBR) with the sausage technique utilized a resorbable collagen membrane, made of a 50% autologous bone and a 50% anorganic bovine bone matrix (ABBM) mixture. After 6 months, a CBCT (T1) was performed before implant placement. Using CBCT software, a plane parallel to the implant axis intersected perpendicular planes every 1.5 mm from the crest level. T0 and T1 CBCT sections were analyzed, yielding 140 measurements. Statistical analysis via SPSS revealed a significant increase in thickness (average 2.82 ± 1.79 mm). Maximum gains occurred at 4.5 mm from the coronal crest line (3.8 ± 1.51 mm). The GBR sausage technique was effective with minimal post-operative complications, yielding the biggest gain at the mid-ridge sagittal area. Within the analysis limitations, it can be assumed that the sausage technique is effective for horizontal GBR in the maxilla, but a lesser volume might be achieved at the crestal level because it seems to follow a bowed regeneration shape.

Rejuvenation of bone volume with CGF and i-PRF in intra-osseous defects.

The risk of further periodontal breakdown increases with a deep intrabony defect. Non-surgical periodontal therapy could pose a challenge and surgical intervention is mainly required to manage the defect. Autologous platelet concentrates such as Injectable platelet rich fibrin (i-PRF) and concentrated growth factor (CGF) may improve surgical outcome due to its enrichment with growth factors. Total of 04 patients involved in this study. After conventional flap debridement of intrabony defects, CGF is placed in 2 patients and the other 2 patients received i-PRF in their respective intrabony defects. Volumetric analysis was done pre-operative and 6 months post operatively in both the groups. Bone volume is significantly increased in both CGF and i-PRF group but higher in CGF group when compared to i-PRF group has high regenerative and reconstructive growth factors which helps aids in early and high bone fill when compared to i-PRF.

Quantitative analysis of change in bone volume 5 years after sinus floor elevation using plate-shaped bone substitutes: a prospective observational study.

PURPOSE: Tricalcium phosphate (TCP) has osteoconductive ability and reportedly offers similar clinical results as autogenous bone grafts in dental implant treatment. However, few reports quantify temporal changes in augmented bone volume after sinus augmentation. We aimed to establish a three-dimensional (3D) quantification method to assess bone volume after sinus augmentation and to evaluate biocompatibility of the TCP plate. METHODS: Maxillary sinus floor augmentation was performed employing the lateral window technique, and plate-shaped ß-TCP (TCP plate) was used instead of granular bone grafting materials. After lifting the sinus membrane, the TCP plate was inserted and supported by dental implants or micro-screws. The changes in bone volumes in the maxillary sinus before and after surgery were recorded using cone-beam computed tomography, saved as Digital Imaging and Communications in Medicine-formatted files, and transformed to Standard Triangle Language (STL)-formatted files. Pre- and post-operative STL data of bone volume were superimposed, and the augmented bone volume was calculated. Moreover, changes in bone volumes, TCP plate resorption rates, and bone heights surrounding the implants were three dimensionally quantified. RESULTS: Fifteen implants in nine subjects were included in this study. TCP plates secured long-term space making, with results similar to those of granular bone substitutes. Newly formed bone was identified around the implant without bone graft material. TCP plate was absorbed and gradually disappeared. CONCLUSIONS: A novel 3D quantification method was established to evaluate changes in bone volume. Clinical application of TCP plate in sinus augmentation could be a better procedure in terms of prognosis and safety.

Trabecular bone morphology in big cats reflects the complex diversity of limb use but not home range size or daily travel distance.

A relationship exists between mechanical loading and bone morphology. Although studies show a relationship between trabecular bone morphology and locomotor strategy in mammals, none of them have studied trabecular bone morphology in felid species occupying disparate and overlapping habitats. We investigate trabecular bone volume fraction (BVF) in the femoral and humeral heads, and distal tibia of four felid species (mountain lions, jaguars, cheetahs, and leopards) to identify whether there is a relationship between BVF and locomotor behavior. This study's goals are to identify whether felid species with high daily travel distance or large home range size have greater BVF compared with those with small daily travel distance or home range size, and whether BVF is correlated among the three elements of the fore and hindlimb studied. We quantified BVF in micro- and peripheral computed tomography images and found no significant differences across species in the femoral and humeral head (p > 0.05). However, in the distal tibia, results showed that leopards, mountain lions, and cheetahs have significantly greater (p < 0.05) BVF than jaguars. Despite differences in home range size and daily travel distance, the proximal elements did not reflect differences in BVF; however, the distal-most element did, suggesting decreased loading among jaguars. These findings suggest that the observed pattern of trabecular bone morphology is potentially due to the diversity in locomotor strategy of the forelimb. Additionally, these results imply that neither home range size nor daily travel distance are clear indicators of activity levels. A cautious approach is warranted in studying how loading influences trabecular morphology.

The Effect of Platelet-Rich Plasma on Bone Volume in Secondary Alveolar Bone Grafting in Alveolar Cleft Patients: A Systematic Review.

This systematic review aims to investigate the impact of platelet-rich plasma (PRP) in conjunction with bone grafting on bone volume outcomes in secondary alveolar bone grafting (SABG) procedures among alveolar cleft patients. An exhaustive search involving PubMed, Cochrane, and Google Scholar databases yielded 20 relevant titles, ultimately leading to the inclusion of four articles meeting all specified criteria. Based on the Cochrane risk of bias in systematic reviews (ROBIS) tool, the studies showed a high risk of bias. The primary outcome, bone volume assessment, was analyzed across these articles. While the Cochrane ROBIS tool deemed the included articles to have a high risk of bias, the comparison between PRP and Non-PRP groups did not reveal a significant difference in bone volume. Radiographic data illustrated an initial three-month period of bone resorption post-graft, regardless of PRP application, followed by a six-month phase of heightened bone density, particularly discernible in the PRP groups. To sum up, our findings indicate an absence of substantial bone density increase in cleft patients undergoing SABG with PRP augmentation. Nonetheless, there was a modest trend that suggests potential incremental bone density improvement with PRP usage, underscoring the need to conduct rigorously designed, randomized controlled trials (RCTs) with low bias to validate these observations.

The efficacy of alveolar ridge split on implants: a systematic review and meta-analysis.

OBJECTIVES: To evaluate the effects of the alveolar ridge split (ARS) technique on gained horizontal width of the alveolar ridge and implant survival rate. MATERIALS AND METHODS: Electronic searching was performed in six electronic databases (Pubmed, Embase, the Cochrane Central Register of Controlled Trials, Web of Science, China National Knowledge Infrastructure, and SIGLE) from January 1, 2010, to November 1, 2023. Two authors performed study selection, data extraction, and study qualities (ROBINS-I and RoB 2.0) independently. Meta-analysis was performed by Comprehensive meta-analysis 3.0. RESULTS: 24 included studies were observational, and 1 study was a randomized controlled trial (RCT). 14 studies investigated the gained width of the horizontal alveolar ridge, and 17 examined the implants' survival rate. For assessment of risk of bias, nine studies were high risk of bias and 16 studies were moderate risk of bias. Meta-analysis demonstrated that the pooled gained alveolar ridge width was 3.348 mm (95%CI: 4.163 mm, 2.533 mm), and the implant survival rate was 98.1% (95%CI: 98.9%, 96.9%). Seven studies showed seven different complications including exposure, infection, bad split, dehiscence, fracture, paresthesia and soft tissue retraction. CONCLUSION: Recent ARS technique seems to be an effective method of bone augmentation with enough gained width and a high implant survival rate. Further long-term and RCTs research remains needed to enhance the study quality. CLINICAL RELEVANCE: The ARS technique could generate sufficient bone volume, and implants had a high-level survival rate. Therefore, ARS has been proposed to be a reliable horizontal bone augmentation technique that creates good conditions for the implantation of narrow alveolar crests.

Effect of Selective Serotonin Reuptake Inhibitor (Paroxetine) on Newly Formed Bone Volume: Real-Time In Vivo Micro-computed Tomographic Analysis.

INTRODUCTION: Selective serotonin reuptake inhibitors (SSRIs) are commonly used to treat depression and anxiety. The purpose of this study was to assess in real time the effect of paroxetine, an SSRI, on newly formed bone volume (NFBV) in standardized calvarial defects (SCDs) in rats. METHODS: Fourteen Wistar albino female rats with a mean age of 7.5 months and a mean weight of 275 g were used. The animals were randomly divided into 2 groups. The experimental group was given paroxetine 8 weeks before the surgical procedure and throughout the experiment, and the control group was given a placebo 8 weeks before the surgical procedure and throughout the experiment. In each group, 14 SCDs measuring 4.6 mm in diameter were created on the parietal bone. In both groups, a Bio-Oss + collagen membrane was placed. All defects showed primary closure. The volume of the newly formed bone (NFBV) was measured using in vivo micro-computed tomographic imaging. Measurements were taken at days 0, 14, 28, 42, and 56 after surgery using real-time assessment with micro-computed tomographic imaging. RESULTS: The mean NFBV was 17.12 ± 4.52 mm3 and 12.52 ± 4.78 mm3 for the control and experimental groups, respectively, at day 56. The differences between the 2 groups were statistically significant (P < .05) at all time intervals. CONCLUSIONS: Paroxetine intake significantly reduced the amount of regenerated NFBV and the rate of new bone formation.

Retrospective analysis of three different xenografts in maxillary sinus augmentation: histologic and three-dimensional radiologic study.

OBJECTIVES: Low bone density and lack of adequate vertical bone dimension as a result of maxillary sinus pneumatization present some of the most problematic cases for endosseous implant applications in posterior maxillary regions that hinder prosthetic rehabilitation. The overall objectives of the study were to assess the histologic, histomorphometric, and radiologic evaluation of biopsies gathered from maxillary sinuses that were grafted with three different bovine bone particles (Bio-Oss, Cerabone, and Ti-Oss) and analyze the volume of the bone graft and the quantity of new bone formation. METHOD AND MATERIALS: Thirty-six patients with < 4 mm of residual ridge height unilaterally in the posterior maxilla were equally divided into three groups, each of which received different bovine bone particles for maxillary sinus augmentation. Six months later, biopsies were harvested for histologic and histomorphometric evaluations. Volumetric changes in maxillary sinus augmentation were analyzed at 1-week and 6-month time-points following maxillary sinus augmentation surgery. RESULTS: Histomorphometric and histologic analysis revealed a significant difference between the Ti-Oss group compared with the Bio-Oss and Cerabone groups (P = .011). In terms of residual graft particles and soft tissue, there were no significant differences between groups. 3D volumetric reductions between 1-week (baseline) and 6-month time-points recorded significant graft volume reduction in all groups (P < .05). Significantly greater bone resorption and lower new-bone formation were manifested in the Ti-Oss group in comparison to the other groups. CONCLUSIONS: Within the limits of this study, histologic and radiologic results indicated that Bio-Oss and Cerabone could be used efficiently in sinus augmentation procedures, while further prospective studies are needed to evaluate the Ti-Oss material in maxillary sinus augmentation.

Extracorporeal Shock Wave Therapy as a Helpful Method for Rapid Osseointegration of Dental Implants: Animal Study.

The aim of this study was to assess the multi-phasic use of extracorporeal shock wave therapy (ESWT) as an adjuvant treatment to accelerate the osseointegration of titanium dental implants. Initially, twelve titanium mini-screws were inserted in femur bones of six New Zealand rabbits in three groups; the one-time treated group, the three-time treated group, and the control group (without ESWT). Then, 1800 focused shockwaves with an energy flux density of 0.3 mJ/mm2 in every phase were used. Fourteen days after the last phase of ESWT, the animals were sacrificed to assess the osseointegration of screws via micro-computed tomography scan (micro-CT scan), biomechanical pull-out test, and histopathological analysis. Pull-out and histopathology analysis showed that the ESWT significantly increased bone regeneration and osseointegration around the implants compared to the control group (p < 0.05). Moreover, the pull-out test confirmed that the three-time treated screws needed more force to pull the bone out compared to the other two groups (p < 0.05). The mean bone volume fraction between the control group, the one-time treated group, and the three-time treatment group were not statistically significant (p > 0.05) according to the micro-CT scan results. Based on our results, ESWT can be suggested as a non-invasive and cost-effective adjuvant for osseointegration of dental implants. However, more in vivo studies and clinical trials are needed for validation of this finding.

Modeling and simulation of bone cells dynamic behavior under the late effect of breast cancer treatments.

Breast Cancer (BC) treatments have been proven to interfere with the health of bones. Chemotherapy and endocrinal treatment regimens such as tamoxifen and aromatase inhibitors are frequently prescribed for women with BC. However, these drugs increase bone resorption and reduce the Bone Mineral Density (BMD), thus increasing the risk of bone fracture. In the current study, a mechanobiological bone remodeling model has been developed by coupling cellular activities, mechanical stimuli, and the effect of breast cancer treatments (chemotherapy, tamoxifen, and aromatase inhibitors). This model algorithm has been programmed and implemented on MATLAB software to simulate different treatment scenarios and their effects on bone remodeling and also predict the evolution of Bone Volume fraction (BV/TV) and the associated Bone Density Loss (BDL) over a period of time. The simulation results, achieved from different combinations of Breast Cancer treatments, allow the researchers to predict the intensity of each combination treatment on BV/TV and BMD. The combination of chemotherapy, tamoxifen, and aromatase inhibitors, followed by the combination of chemotherapy and tamoxifen remain the most harmful regimen. This is because they have a strong ability to induce the bone degradation which is represented by a decrease of 13.55% and 11.55% of the BV/TV value, respectively. These results were compared with the experimental studies and clinical observations which showed good agreement. The proposed model can be used by clinicians and physicians to choose the most appropriate combination of treatments, according to the patient's case.

Effects of obesity on talar micro- and macro-morphology.

The addition of information regarding obesity status to the forensic anthropological biological profile could significantly contribute to the identification of human skeletal remains since over 40% of the U.S. adult population is currently obese. This study examines the differences in talar shape and trabecular bone structure between obese and non-obese individuals. A sample of 20 obese and 20 non-obese divided evenly by sex was selected from the Texas State University Donated Skeletal Collection. Tali were imaged using x-ray computed tomography (voxel size: 28-38.7 µm). Image stacks were processed to produce binary images as well as trabecular thickness and spacing maps. Landmark-based geometric morphometric analyses were conducted to quantify shape variation. Shape coordinates were used to locate 100 geometrically homologous volumes of interest within each talus. Bone volume fraction, trabecular thickness, and trabecular spacing were extracted at each volume of interest. Within each sex, a one-way ANCOVA was used to determine if significant differences exist between obese and non-obese individuals in trabecular bone after controlling for age. The size of the talus as well as subtle aspects of shape were found to distinguish the sexes. The results further indicate that bone volume fraction significantly differs between obese and non-obese males. In females, bone volume fraction is correlated with age but does not differ between obese and non-obese. The study demonstrates that bone microstructure is a promising approach to estimating body mass or body mass index category but age effects diminish the potential for the talus to be used alone.

Bone-targeted bortezomib increases bone formation within Calvarial trans-sutural distraction osteogenesis.

The high rate of relapse in craniofacial disharmony treatment via trans-sutural distraction osteogenesis (TSDO) is due to the failure to form a stable bone bridge in the suture gap. Bisphosphonates (BP) have a high propensity to localize to hydroxyapatite in the bone matrix and are commonly used as targeting ligands for local delivery of therapeutics into bone microenvironment. Bone-targeted Bortezomib (BP-Btz) is chemosynthetic by linking Btz (Bortezomib) to a BP residue and could target bone tissue to promote osteoblast differentiation and inhibit osteoclastogenesis. Here, suture-derived mesenchymal stem cells (SuSCs) and osteoclasts were treated with Btz and BP-Btz. Aforesaid drugs were injected locally into the sagittal sutures to explore their effects in TSDO. Further, pharmacological properties of BP-Btz in the suture expansion model were assessed by fluorescent BP analogs and levels of total ubiquitinated (Ub)-proteins. The results showed that BP-Btz could stimulate osteogenic differentiation of SuSCs, bind to bone matrix and inhibit osteoclastogenesis. Biological effects of BP-Btz were similar with those of Btz in osteoblast differentiation and osteoclastogenesis inhibition in vitro. Activated bone metabolism were detected after 14 days in the sagittal suture expansion model. Increased osteoid area, remarkably decreased osteoclast surface and enhanced osteogenesis were detected in vivo after treatment with BP-Btz. Green fluorescence signal detection and pharmacodynamic studies revealed that BP-Btz bound to suture edge, released Btz in remodeling conditions, had a higher local concentration and sustained longer than free Btz. This study delineated the clinical potential of bone-targeted Btz conjugate as an efficacious strategy to promote trans-sutural distraction osteogenesis.