Mean Bone Volume Research Articles

In vivo validation of osteoinductivity and biocompatibility of BMP-2 enriched calcium phosphate cement alongside retrospective description of its clinical adverse events

PurposeAlthough bone morphogenetic protein-2 (BMP-2) possesses potent osteoinductivity, there have been some concerns on the safety of BMP-2 and BMP-2-incorporated bone substitutes used for bone formation. On the other hand, BMP-2-loaded calcium phosphate cement (BMP-2@CPC) has been developed and used for bone regeneration in oral implantology. Therefore, this study aims to investigate this product's biocompatibility and clinical safety after being used in maxillofacial surgery.Materials and methodsA rat model was employed to assess the osteoinduction and biocompatibility of BMP-2@CPC. Further, a retrospective investigation was carried out: 110 patients who received BMP-2@CPC treatment after their maxillofacial surgery were recruited to describe relative adverse events.ResultsIn vivo, BMP-2@CPC showed a significantly higher mean bone volume density and osteoblasts volume density (15 ± 2% and 3 ± 1%)than those of the CPC group (p < 0.05) after being implanted in the dorsal area of rats. Regarding biocompatibility, the mean fibrous tissue volume density was significantly lower in the BMP-2@CPC group (20 ± 5% compared to 31 ± 6%, p = 0.026). The retrospective clinical study showed that only five mild/moderate adverse events were identified in four patients based on the medical records of 110 patients, including swelling, bony mass, and wound dehiscence. This adverse event occurrence was not affected by gender, age, the dose of filled materials, and operations in the study (p > 0.05).ConclusionsBMP-2-loaded CPC has osteoinductivity and more promising biocompatibility than pure CPC. However, its degradation is slower than CPC. The safety of BMP-2-loaded CPC with 0.5 or 1 mg BMP-2 is promising in oral maxillofacial surgery.Clinical implicationsThis study confirmed the promising safety of this BMP-2 incorporated CPC used in dental clinical practice, which can promote its reassuring application for dental implant placement in bone insufficient areas.Graphical

Transdermal delivery of bisphosphonates using dissolving and hydrogel-forming microarray patches: Potential for enhanced treatment of osteoporosis

As of 2023, more than 200 million people worldwide are living with osteoporosis. Oral bisphosphonates (BPs) are the primary treatment but can cause gastrointestinal (GI) side effects, reducing patient compliance. Microarray (MAP) technology has the potential to overcome GI irritation by facilitating the transdermal delivery of BPs. This study examines the delivery of alendronic acid (ALN) and risedronate sodium (RDN) using dissolving and hydrogel-forming MAPs for osteoporosis treatment. In vivo testing on osteoporotic female Sprague Dawley rats demonstrated the efficacy of MAPs, showing significant improvements in mean serum and bone alkaline phosphatase levels, bone volume, and porosity compared to untreated bilateral ovariectomy (OVX) controls. Specifically, MAP treatment increased mean bone volume to 55.04 ± 2.25 % versus 47.16 ± 1.71 % in OVX controls and reduced porosity to 44.30 ± 2.97 % versus 52.84 ± 1.70 % in the distal epiphysis of the femur. In the distal metaphysis, bone volume increased to 43.32 ± 3.24 % in MAP-treated rats compared to 24.31 ± 3.21 % in OVX controls, while porosity decreased to 55.39 ± 5.81 % versus 75.69 ± 3.21 % in OVX controls. This proof-of-concept study indicates that MAP technology has the potential to be a novel, patient-friendly alternative for weekly osteoporosis management.

A three-dimensional quantitative assessment on bony growth and symmetrical recovery of mandible after decompression for unicystic ameloblastoma

Unicystic ameloblastoma (UAM) of the jaw can be effectively reduced in volume through decompression, which promotes bone regeneration and restores jaw symmetry. This study quantitatively evaluated changes in mandible volume and symmetry following decompression of mandibular UAM. This study included 17 patients who underwent surgical decompression followed by second-stage curettage for mandibular UAM. Preoperative and postoperative three-dimensional computed tomography (CT) images were collected. Bone volume and the area of cortical perforation were measured to assess bone growth during decompression. Mandibular volumetric symmetry was analyzed by calculating the volumetric ratio of the two sides of the mandible. Twelve pairs of landmarks were identified on the surface of the lesion regions, and their coordinates were used to calculate the mean asymmetry index (AI) of the mandible. Paired t-tests and the Mann–Whitney U test were used for statistical analysis, with p < 0.05 considered indicative of statistical significance. The mean duration of decompression was 9.41 ± 3.28 months. The mean bone volume increased by 8.07 ± 2.41%, and cortical perforation recovery was 71.97 ± 14.99%. The volumetric symmetry of the mandible improved significantly (p < 0.05), and a statistically significant decrease in AI was observed (p < 0.05). In conclusion, UAM decompression enhances bone growth and symmetry recovery of the mandible. The present evaluation technique is clinically useful for quantitatively assessing mandibular asymmetry.

Macrophages modulate mesenchymal stem cell function via tumor necrosis factor alpha in tooth extraction model.

Mesenchymal stem cells (MSCs) and macrophages collaboratively contribute to bone regeneration after injury. However, detailed mechanisms underlying the interaction between MSCs and inflammatory macrophages (M1) remain unclear. A macrophage-depleted tooth extraction model was generated in 5-wk-old female C57BL/6J mice using clodronate liposome (12.5mg/kg/mouse, intraperitoneally) or saline injection (control) before maxillary first molar extraction. Mice were sacrificed on days 1, 3, 5, 7, and 10 after tooth extraction (n = 4). Regenerated bone volume evaluation of tooth extraction socket (TES) and histochemical analysis of CD80+M1, CD206+M2 (anti-inflammatory macrophages), PDGFRα+MSC, and TNF-α+ cells were performed. In vitro, isolated MSCs with or without TNF-α stimulation (10ng/mL, 24h, n = 3) were bulk RNA-sequenced (RNA-Seq) to identify TNF-α stimulation-specific MSC transcriptomes. Day 7 micro-CT and HE staining revealed significantly lower mean bone volume (clodronate vs control: 0.01mm3 vs 0.02mm3, p<.0001) and mean percentage of regenerated bone area per total TES in clodronate group (41.97% vs 54.03%, p<.0001). Clodronate group showed significant reduction in mean number of CD80+, TNF-α+, PDGFRα+, and CD80+TNF-α+ cells on day 5 (306.5 vs 558.8, p<.0001; 280.5 vs 543.8, p<.0001; 365.0 vs 633.0, p<.0001, 29.0 vs 42.5, p<.0001), while these cells recovered significantly on day 7 (493.3 vs 396.0, p=.0004; 479.3 vs 384.5, p=.0008; 593.0 vs 473.0, p=.0010, 41.0 vs 32.5, p=.0003). RNA-Seq analysis showed that 15 genes (|log2FC| > 5.0, log2TPM > 5) after TNF-α stimulation were candidates for regulating MSC's immunomodulatory capacity. In vivo, Clec4e and Gbp6 are involved in inflammation and bone formation. Clec4e, Gbp6, and Cxcl10 knockdown increased osteogenic differentiation of MSCs in vitro. Temporal reduction followed by apparent recovery of TNF-α-producing M1 macrophages and MSCs after temporal macrophage depletion suggests that TNF-α activated MSCs during TES healing. In vitro mimicking the effect of TNF-α on MSCs indicated that there are 15 candidate MSC genes for regulation of immunomodulatory capacity.

Application of sticky bone combined with concentrated growth factor (CGF) for horizontal alveolar ridge augmentation of anterior teeth: a randomized controlled clinical study.

This study was designed to estimate the effect of sticky bone combined with concentrated growth factor (CGF) on anterior alveolar horizontal augmentation during implantation. Twenty-eight patients were randomly assigned to either the test group (Group 1, n = 14) or the control group (Group 2, n = 14). Patients in Group 1 and Group 2 underwent GBR using sticky bone combined with CGF and bone powders mixed with saline, respectively. On postoperative Day 7, the patients completed the visual analogue scale (VAS). Three-dimensional models of maxillary alveolar bone were reconstructed from CBCT data at different periods, and the bone volume conversion rate was calculated with the assistance of a measurement marker guide. Labial bone thickness before and after trauma closure and bone density at six months postoperatively were also measured. The mean bone volume conversion rate for Group 1 (72.09 ± 12.18%) was greater than that for Group 2 (57.47 ± 9.62%, P = 0.002). The VAS score was lower for Group 1 than for Group 2 (P = 0.032). At six months postoperatively, greater bone density was found in patients in Group 1 than in those in Group 2, although the difference was not statistically significant (P > 0.05). The change in the thickness of the labial bone graft material in Group 1 was smaller than that in Group 2 (P = 0.025). Sticky bone combined with CGF was able to achieve better bone augmentation than conventional GBR. With excellent mechanical properties and the capacity to release growth factors, sticky bone is an ideal material for bone grafting. The study was registered at the Chinese Clinical Trial Registry on 10/04/2022 (Identification number: ChiCTR2200058500).

Zoledronic acid enhances tumor growth and metastatic spread in a mouse model of jaw osteosarcoma.

Investigation of the therapeutic effect of zoledronic acid (ZA) in a preclinical model of jaw osteosarcoma (JO). The effect of 100 μg/kg ZA administered twice a week was assessed in a xenogenic mouse model of JO. The clinical (tumor growth, development of lung metastasis), radiological (bone microarchitecture by micro-CT analysis), and molecular and immunohistochemical (TRAP, RANK/RANKL, VEGF, and CD146) parameters were investigated. Animals receiving ZA exhibited an increased tumor volume compared with nontreated animals (71.3 ± 14.3 mm3 vs. 51.9 ± 19.9 mm3 at D14, respectively; p = 0.06) as well as increased numbers of lung metastases (mean 4.88 ± 4.45 vs. 0.50 ± 1.07 metastases, respectively; p = 0.02). ZA protected mandibular bone against tumor osteolysis (mean bone volume of 12.81 ± 0.53 mm3 in the ZA group vs. 11.55 ± 1.18 mm3 in the control group; p = 0.01). ZA induced a nonsignificant decrease in mRNA expression of the osteoclastic marker TRAP and an increase in RANK/RANKL bone remodeling markers. The use of bisphosphonates in the therapeutic strategy for JO should be further explored, as should the role of bone resorption in the pathophysiology of the disease.

Alveolar Ridge Preservation Using the One-Piece Autologous Tuberosity Graft: A Clinical, Radiological, and Histological Pilot Study.

This prospective study investigated clinically and radiologically the effectiveness of the use of a combined hard and soft tissue graft retrieved from the maxillary tuberosity and designed for alveolar ridge preservation following tooth extraction. Seven patients scheduled for a single mono-rooted tooth extraction were included in the study. After atraumatic extraction, sockets were filled with a "one-piece" dual tissue graft harvested from the tuberosity using an adjusted trephine. CBCTs were performed before the extraction and 4 months after ridge preservation, to analyze the vertical and horizontal alterations of the ridge, using ITK-Snap software. Clinical measurements of both soft and hard tissues were also assessed during the extraction and implant placement. All sites healed uneventfully. After 4 months, the 3D super-imposition of both CBCTs showed a mean bone volume resorption of 65 ± 76.7 mm3 (10.2 ± 10%). The mean horizontal reduction at 2, 4, and 6 mm from the top of the crest was respectively 1.5 ± 1.3 mm, 0.47 ± 1.4 mm and 0.57 ± 0.7 mm, while the mean vertical loss was 0.026 mm ± 2 mm. The mean soft tissue horizontal gain was 1.73 ± 1.12 mm. The "one-piece" autologous tuberosity graft was proven to be a safe and effective alveolar ridge preservation technique and may represent a feasible, user-friendly, time saving, low-cost solution for minimizing dimensional loss following tooth extraction.

Evaluation of Guided Bone Regeneration Using Xenograft/APRF Mixture in Atrophic Posterior Mandible (Clinical and Radiographic Study)

Introduction: The rehabilitation of the posterior mandible with dental implants represents a hard challenge for clinicians today due to the lack of supporting bone. Different surgical techniques are currently being used to augment the posterior mandible, where GBR is considered the most commonly used. Materials and Methods: Fifteen patients were selected to treat mandibular alveolar ridge resorption with guided bone regeneration using a titanium-reinforced membrane and a filling mixture of xenograft bovine bone and PRF. The membrane was fixed using a Meisinger pin control kit and Profix 3mm microscrews. A PRF membrane was used to cover the Ti-d-ptfe.&#x0D; Results: Swelling, pain, and numbness were evaluated using the mixture of PRF/xenograft as well as PRF membranes. The results showed promising results in terms of primary wound healing, whereas a significant bone quantity with a mean bone volume of 5.78 ± 0.81 was reported after 6 months. The primary implant stability recorded high values and significantly increased at a period of 6 months post-insertion (p = 0.037). Conclusion: It could be concluded that the PFR/xenograft mixture can be promising when used with the titanium-reinforced d-ptfe membrane in 3D ridge reconstruction of the atrophic posterior mandible; moreover, using the PRF membrane to cover the TI-d-ptfe membrane could enhance soft tissue healing as well as prevent soft tissue dehiscence due to the concentration of growth factors that can be released during primary wound healing. The xenograft/PRf mixture can be consistently utilized for the creation of new bone in severely atrophic ridges if used in GBR. The high ISQ at primary implant placement and at a period of 6 months post-insertion, according to Osstell, can explain the successful application of this mixture in 3D bone augmentation of the atrophic posterior mandible.

Changes in Volume and Bone Density of Calvarial Grafts After Two Years of Orbital Reconstruction.

One of the greatest challenges in orbital reconstruction is to obtain adequate orbital volume and globe projection after traumatic injury. Autologous bone graft has been considered the gold standard for orbital floor reconstruction, but the harvesting yields many possible complications, such as donor site morbidity. Bone resorption is a frequent problem that can lead to insufficient volume after graft placement. There is a theoretically lower resorption rate of skull bone grafts, even though the exact amount is not known yet. This study is the first to evaluate bone volume and density changes of calvarial split bone grafts after orbital floor reconstruction with a 2-year follow-up. Bone volume and density of calvarial split grafts were determined using computed tomography scans and the software program RadiAnt Dicom Viewer in a total of 10 patients with orbital floor fracture reconstruction. Computed tomography scans taken immediately after surgery (T0) and after a postoperative period of 2 years (T1) were evaluated. The authors found a mean bone volume reduction of 34.25% after 2 years. Bone density was still high after 2 years (over 850 HU), with a mean reduction of 8%. Based on these findings, calvarial split bone grafts represent the ideal reconstruction material for orbital floor fractures.

Photofunctionalization of Dental Implant Surfaces - A Histomorphometric Animal Study.

To compare and evaluate the degree of osseointegration of UV-treated (photo functionalized) and non-treated dental implants surface coated with Calcium phosphate using the Resorbable Blast Media (RBM) technique in an animal model. Evaluative-Animal study design. Six titanium dental implants of diameter 3.2 mm and length of 8 mm with Calcium phosphate coated surface using RBM or resorbable blast media technology (Implant Genesis: Genesis Normo Implant system) were placed epicrestally into the proximal femoral condyle of New Zealand white female rabbits such that each animal received two implants. Before implantation, one out of the two dental implants was photo functionalized with intense UV light for 15 minutes. After twelve weeks of healing, the animals were euthanized and the harvested specimens were analyzed using histomorphometric light microscopy to assess two parameters bone-implant contact and bone volume density. SPSS version 23. P less than 0.05 is considered statistically significant. Tests used ANOVA followed by Tukey post hoc test. All six dental implants were osseointegrated. The overall mean bone-implant contact area (BIC) was 57.76% for non-UV treated whereas 88.4367% for UV-treated dental implants. The overall mean bone volume density (BVD) was 32.2333% for non-UV treated whereas 67.7533% for UV-treated dental implants. Significant effects were observed on the osseointegration of dental titanium implants within twelve weeks after UV photo functionalization. The UV photo functionalization of dental titanium implants in the current study significantly altered the BIC and bone density on osseointegration when observed over twelve weeks.

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.

Usefulness of quantitative bone SPECT/CT for evaluating medication-related osteonecrosis of the jaw treatment response.

For assessment of therapeutic response in medication-related osteonecrosis of the jaw (MRONJ) cases, the clinical usefulness of quantitative bone single-photon computed tomography-computed tomography (SPECT/CT) results was investigated. Sixteen patients (18 lesions) with a clinical diagnosis of MRONJ underwent bone SPECT/CT scanning before and during/after anti-inflammatory therapy given for 3 or more months. The GI-BONE software package was used to determine standard uptake values (SUVs), including maximum (SUVmax), peak (SUVpeak), and mean (SUVmean), and metabolic bone volume (MBV) and also total bone uptake (TBU). In both responders (downstage) and non-responders (upstage or no change), differences in quantitative values between the first and second SPECT/CT examinations were analyzed using a Wilcoxon test. Following therapy, significant reductions in SUVmax, SUVpeak, SUVmean, MBV and TBU values for 11 lesions were noted in the responders after therapy (p = 0.003, p = 0.006, p = 0.004, p = 0.003, and p = 0.002, respectively). On the other hand, those for the seven lesions in the non-responder group were not significantly different (p = 0.17, p = 0.16, p = 0.26, p = 0.96, and p = 0.12, respectively). Results for SUVmax change showed sensitivity and specificity values of 45.5% and 85.7%, respectively, for differentiating responders from non-responders, with -37.3% the optimal cutoff value. Those for MBV change were 72.7 and 85.7%, respectively, with -29.4% the optimal cutoff value. Those for TBU change were 81.8% and 85.7%, respectively, with -36.3% the optimal cutoff value. The present findings showed that therapeutic response in MRONJ cases could be determined by use of quantitative SUV, MBV, and TBU values based on bone SPECT/CT findings.

Comparison of the efficacy of intra-articular injections of hyaluronic acid and lactoferrin in mono-iodoacetate-induced temporomandibular joint osteoarthritis: A histomorphometric, immunohistochemistry, and micro-computed tomography analysis.

This study aims to evaluate the efficacy of high-molecular-weight hyaluronic acid (HMWHA) and lactoferrin (LF) injections on temporomandibular joint (TMJ) cartilage and subchondral bone in mono-iodoacetate (MIA)-induced temporomandibular joint osteoarthritis model in rats. In this in vivo study, a total of 24 rats were divided into three groups as follows: saline group (Group 1), HMWHA group (Group 2), and LF group (Group 3) including eight rats in each group. The intra-articular injections were administered once a week for three weeks after osteoarthritis was induced. All animals were euthanized 28 days after induction of osteoarthritis, and TMJs were harvested for histomorphometric, immunohistochemical, and micro-computed tomography (CT) analysis. There was no significant difference between the HMWHA and LF groups in terms of the histomorphometric and immunohistochemical analysis results (p>0.05). According to the micro-CT analysis, the LF group had the highest mean bone volume fraction (74.9±0.5) and trabecular thickness (0.122±0.002), while the saline group had the lowest mean values (55.0±0.3 and 0.071±0.002, respectively) (p<0.001). There was no significant difference between the HMWHA and LF groups according to the micro-CT analysis (p>0.05). Both groups had better healing effects than the saline group in all analyses. Lactoferrin has a healing effect at least as much as HMWHA in MIA-induced TMJ osteoarthritis. We suggest that LF may be evaluated in future clinical studies as a promising agent in the treatment of osteoarthritis.

Micro-CT evaluation of bone grow concept of an implant with microstructured backtaper crestally and sub-crestally placed. Preliminary study in New Zealand rabbits tibia at one month

&lt;abstract&gt; &lt;p&gt;The primary purpose of this study was to determine the accuracy of micro-computed tomography (micro-CT) as a novel tool for the 3D analysis of bone density around dental implants in tibia rabbits. Six male New Zealand rabbits were used in our evaluation. One Copa SKY® (Bredent Medical GmbH &amp;amp; Co. K.G.) with a 3.5 mm diameter by 8.0 mm in length was placed within 12 tibia rabbits divided into two experimental groups: Group A (crestal placement) and Group B (sub-crestal placement). The animals were sacrificed at four weeks. Micro-CT evaluations showed a high amount of bone around all implants in the tibia rabbit bone. There was an increased formation of bone around the Copa SKY implants, mainly in the implants that were placed crestally. The most frequent density found in most implants was a medullary bone formation surrounding the implant; the density three (D3) was the most common type in all implants. The 3D model analysis revealed a mean bone volume (B.V.) of 31.24 ± 1.24% in crestal implants compared with the 43.12 ± 0.43% in sub-crestal implants. The mean actual contact implant to bone (B.I.C.) in the sub-crestal group was 51.76 ± 0.86%, compared to the 42.63 ± 0.75% in the crestal group. Compared to crestal implants, the Copa Sky implant placed sub-crestally allows for the formation of bone on top of the neck, thereby stimulating bone growth in tibia rabbits.&lt;/p&gt; &lt;/abstract&gt;

Application of Tissue Engineering in Manufacturing Absorbable Membranes to Improve the Osteopromoting Potential of Collagen.

The membranes are an important biomaterial that contribute to osteopromotion. This study aimed to evaluate the osteopromotive potential of collagen membranes associated with Hydroxyapatite (HA) in critical size calvaria rat's defects. Ninety-six Albinus Wistar rats were divided into four groups: (CG) negative control: clot only (CG); positive control: porcine collagen membrane (BG); fish collagen membrane associated with HA (CP); bovine collagen membrane associated with HA (CB), analyzed at 7, 15, 30, and 60 postoperative days. At 30 days, membrane integrity was observed in the CB and fragments in the CP and BG groups were dispersed in the center of the defect. At 60 days, BG demonstrated better results with no statistical difference for the CP group (p = 0.199) and a statistically significant difference for the CB group (p = 0.013). The inflammatory profiles of the BG and CP groups were similar. Immunohistochemistry demonstrated at 60 days moderate osteopontin staining for the BG and CP groups, light staining for the CB, and intense osteocalcin staining for the BG, while the CB and CP groups demonstrated moderate staining. Microtomography revealed the highest mean bone volume (14.247 mm3) in the BG, followed by the CB (11.850 mm3), and CP (9.560 mm3) group. The collagen membranes associated with HA demonstrated an osteopromotive potential.

Reverse shoulder arthroplasty with metallic augments to preserve bone and restore joint line in patients with glenoid bone loss

BackgroundGlenoid bone loss poses significant challenges for reverse shoulder arthroplasty. In these patients, excess reaming can lead to further bone loss and medialization of the joint line. Metallic augments have been described as a technique for addressing this issue. However, there are currently no studies evaluating the effect of metallic augments on anatomic outcomes. This study evaluates the effect of metallic augments on the glenohumeral joint line and bone preservation. We hypothesize that metallic augments can preserve bone while preventing further medialization of the joint line in patients with preoperative glenoid bone loss. MethodsA prospective single-center, 2-surgeon consecutive case series was evaluated with postoperative computed tomography scans. Three-dimensional reconstruction was used to create models of the scapula and humerus. Comparisons were made with preoperative computed tomography scans using volumetric analysis to evaluate bone loss. The base of the coracoid was used as a constant landmark to assess the joint line position and, by proxy, the center of rotation. Further evaluation of the glenoid version and inclination was measured on the reconstructed models through standardized techniques. ResultsFifteen patients (16 implants) underwent preoperative planning and reverse shoulder arthroplasty with metallic augments from January 1, 2018, to January 1, 2021. The mean follow-up time was 13.1 months. Analysis revealed that augments prevented further medialization of the joint line and corrected the deficit on average by 10.2 mm (range 6.9-14.3; standard deviation 2.0). The mean bone volume removed during surgery was 1292 mm3 (range 525-2256; standard deviation 527), with this value inclusive of the baseplate post volume (∼800 mm3). Inclination and version were restored to acceptable limits in all cases. ConclusionsReverse shoulder arthroplasty with metallic augments reliably preserves bone and prevents medialization of the joint line in patients with preoperative glenoid bone loss. Further research is required to assess the long-term and functional outcomes of this technique.

Evaluation of the Effect of Topical Melatonin Application on Immediately Placed Dental Implants Using Cone Beam Computed Tomography (CBCT).

Aims and objectiveImmediate implants provide ideal three-dimensional positioning compared to conventional implants. There may be a gap between the surface of the implant and the bone walls of the socket when it is inserted into a recently extracted alveolus. To compensate for this, various grafting materials are used. Recently, melatonin has gained significant attention because of its inhibitory action on bone resorption. So, we conducted the study to evaluate the effects of topical melatonin application on immediately placed implants.MethodsThe present study was conducted to compare the radiographic outcomes of immediately placed dental implants with and without topical application of melatonin using cone beam computed tomography (CBCT) with nine months of follow-up. A total of 14 patients were selected, of which seven were placed without the application of melatonin and seven were placed along with the application of melatonin. Within four months, all the implants were loaded functionally with permanent prostheses. Mean crestal bone levels, bone volume, and bone density are evaluated in both groups.ResultsThere was no statistically significant difference in the amount of crestal bone loss near immediately inserted implants in the melatonin group as compared to the control group. In the bone volumetric analysis and bone density, the overall mean bone volume loss is less in the melatonin group. The statistical significance of the difference was determined.ConclusionsThe present study seems to support the hypothesis that the topical application of melatonin in immediately placed dental implants provides with better osseointegration and good survival rates.

Biomechanical structure–function relations for human trabecular bone — comparison of calcaneus, femoral neck, greater trochanter, proximal tibia, and vertebra

MicroCT-based finite element models were used to compute power law relations for uniaxial compressive yield stress versus bone volume fraction for 78 cores of human trabecular bone from five anatomic sites. The leading coefficient of the power law for calcaneus differed from those for most of the other sites (p < 0.05). However, after normalizing by site-specific mean values, neither the leading coefficient (p > 0.5) nor exponent (p > 0.5) differed among sites, suggesting that a given percentage deviation from mean bone volume fraction has the same mechanical consequence for all sites investigated. These findings help explain the success of calcaneal x-ray and ultrasound measurements for predicting hip fracture risk.

Bone union-promoting effect of romosozumab in a rat posterolateral lumbar fusion model.

This study investigated the effect of romosozumab on bone union in a rat posterolateral lumbar fixation model. Posterolateral lumbar fixation was performed on 8-week-old male Sprague Dawley rats (n = 20). For bone grafting, autogenous bone (40 mg) was harvested from the spinous processes of the 10th thoracic vertebra until the 2nd lumbar vertebra and implanted between the intervertebral joints and transverse processes of the 4th and 5th lumbar vertebrae on both sides. Rats were matched by body weight and equally divided into two groups: R group (Evenity®, 25 mg/kg) and control (C) group (saline). Subcutaneous injections were administered twice a week until 8 weeks after surgery. Computed tomography was performed at surgery and week 8 after surgery. The area and percentage of bone trabeculae in the total area of bone fusion were calculated. Statistical analysis was performed using an unpaired t test (p < 0.05). We found that the R group rats had significantly higher mean bone union rate and volume than did the C group rats at all time courses starting week 4 after surgery. The R group had significantly higher increase rates than did the C group at weeks 4 and 6 after surgery. The percentage of bone trabeculae area in the R group was approximately 1.7 times larger than that in the C group. Thus, we demonstrated that romosozumab administration has stimulatory effects on bony outgrowth at bone graft sites. We attribute this to the modeling effect of romosozumab.

Influence of calcium ion-modified implant surfaces in protein adsorption and implant integration

BackgroundCalcium (Ca) is a well-known element in bone metabolism and blood coagulation. Here, we investigate the link between the protein adsorption pattern and the in vivo responses of surfaces modified with calcium ions (Ca-ion) as compared to standard titanium implant surfaces (control). We used LC–MS/MS to identify the proteins adhered to the surfaces after incubation with human serum and performed bilateral surgeries in the medial section of the femoral condyles of 18 New Zealand white rabbits to test osseointegration at 2 and 8 weeks post-implantation (n=9).ResultsCa-ion surfaces adsorbed 181.42 times more FA10 and 3.85 times less FA12 (p<0.001), which are factors of the common and the intrinsic coagulation pathways respectively. We also detected differences in A1AT, PLMN, FA12, KNG1, HEP2, LYSC, PIP, SAMP, VTNC, SAA4, and CFAH (p<0.01). At 2 and 8 weeks post-implantation, the mean bone implant contact (BIC) with Ca-ion surfaces was respectively 1.52 and 1.25 times higher, and the mean bone volume density (BVD) was respectively 1.35 and 1.13 times higher. Differences were statistically significant for BIC at 2 and 8 weeks and for BVD at 2 weeks (p<0.05).ConclusionsThe strong thrombogenic protein adsorption pattern at Ca-ion surfaces correlated with significantly higher levels of implant osseointegration. More effective implant surfaces combined with smaller implants enable less invasive surgeries, shorter healing times, and overall lower intervention costs, especially in cases of low quantity or quality of bone.