Soft Tissue Volume Research Articles

Conceptualizing Scaffold Guided Breast Tissue Regeneration in a Preclinical Large Animal Model.

Scaffold-guided breast tissue regeneration (SGBTR) can transform both reconstructive and cosmetic breast surgery. Implant-based surgery is the most common method. However, there are inherent limitations, as it involves replacement of tissue rather than regeneration. Regenerating autologous soft tissue has the potential to provide a more like-for-like reconstruction with minimal morbidity. Our SGBTR approach regenerates soft tissue by implanting additively manufactured bioresorbable scaffolds filled with autologous fat graft. A pre-clinical large animal study was conducted by implanting 100 mL breast scaffolds (n = 55) made from medical-grade polycaprolactone into 11 minipigs for 12 months. Various treatment groups were investigated where immediate or delayed autologous fat graft, as well as platelet rich plasma, were added to the scaffolds. Computed tomography and magnetic resonance imaging were performed on explanted scaffolds to determine the volume and distribution of the regenerated tissue. Histological analysis was performed to confirm the tissue type. At 12 months, we were able to regenerate and sustain a mean soft tissue volume of 60.9 ± 4.5 mL (95% CI) across all treatment groups. There was no evidence of capsule formation. There were no immediate or long-term post-operative complications. In conclusion, we were able to regenerate clinically relevant soft tissue volumes utilizing SGBTR in a pre-clinical large animal model.

Multiethnic growth standards for fetal body composition and organ volumes derived from 3D ultrasonography

BackgroundA major goal of contemporary obstetrical practice is to optimize fetal growth and development throughout pregnancy. To date, fetal growth during prenatal care is assessed by performing ultrasonographic measurement of two-dimensional fetal biometry to calculate an estimated fetal weight. Our group previously established two-dimensional fetal growth standards using sonographic data from a large cohort with multiple sonograms. A separate objective of that investigation involved the collection of fetal volumes from the same cohort. ObjectiveThe Fetal 3D Study was designed to establish standards for fetal soft tissue and organ volume measurements by three-dimensional ultrasonography and compare growth trajectories with conventional two-dimensional measures where applicable. Study DesignThe NICHD Fetal 3D Study included research-quality images of singletons collected in a prospective, racially and ethnically diverse, low-risk cohort of pregnant individuals at 12 U.S. sites, with up to five scans per fetus (N=1,730 fetuses). Abdominal subcutaneous tissue thickness was measured from two-dimensional images and fetal limb soft tissue parameters extracted from three-dimensional multiplanar views. Cerebellar, lung, liver and kidney volumes were measured using virtual organ computer aided analysis (VOCAL). Fractional arm and thigh total volumes, and fractional lean limb volumes were measured, with fractional limb fat volume calculated by subtracting lean from total. For each measure, weighted curves (5th, 50th, 95th percentiles) were derived from 15-41 weeks’ using linear mixed models for repeated measures with cubic splines. ResultsSubcutaneous thickness of the abdomen, arm, and thigh increased linearly, with slight acceleration around 27-29 weeks. Fractional volumes of the arm, thigh, and lean limb volumes increased along a quadratic curvature, with acceleration around 29-30 weeks. In contrast, growth patterns for two-dimensional humerus and femur lengths demonstrated a logarithmic shape, with fastest growth in the 2nd trimester. The mid-arm area curve was similar in shape to fractional arm volume, with an acceleration around 30 weeks, whereas the curve for the lean arm area was more gradual. The abdominal area curve was similar to the mid-arm area curve with an acceleration around 29 weeks. The mid-thigh and lean area curves differed from the arm areas by exhibiting a deceleration at 39 weeks. The growth curves for the mid arm and thigh circumferences were more linear with some decelerations. Cerebellar two-dimensional diameter increased linearly, whereas cerebellar three-dimensional volume growth gradually accelerated until 32 weeks and then decelerated. Lung, kidney, and liver volumes all demonstrated gradual early growth followed by a linear acceleration beginning at 25 weeks for lungs, 26-27 weeks for kidneys, and 29 weeks for liver. ConclusionGrowth patterns and timing of maximal growth for three-dimensional lean and fat measures, limb and organ volumes differed from patterns revealed by traditional two-dimensional growth measures, suggesting these parameters reflect unique facets of fetal growth. Growth in these three-dimensional measures may be altered by genetic, nutritional, metabolic or environmental influences and pregnancy complications, in ways not identifiable using corresponding two-dimensional measures. Further investigation into the relationships of these three-dimensional standards to abnormal fetal growth, adverse perinatal outcomes, and health status in postnatal life is warranted.

Volumetric Analysis of a Novel Chimeric Gracilis and Profunda Artery Perforator Flap.

The presence of a chimeric gracilis and profunda artery perforator (PAP) flap with a common arterial pedicle has been demonstrated on computed tomography angiography in up to 59% of patients and confirmed in a cadaveric model. Already utilized for head and neck reconstruction by Heredero et al, this novel flap could provide more volume than either flap alone which is advantageous, particularly in patients with sizable defects. The purpose of this study was to determine the average tissue volume that can be utilized from this chimeric flap. CT Angiogram imaging studies exhibiting chimeric flap anatomy were reviewed over a 7-year period at a single institution utilizing Visage Version 7.1, a radiology picture archiving and communication system. This software was used to trace the flap pedicles and to capture estimated soft tissue volumes of each respective flap. A total of 31 patients, consisting of 52 lower extremity gracilis and PAP chimeric flaps, underwent tissue volume analysis. The average total volume of soft tissue supplied by the gracilis flap was found to be 70.21 cm3 (standard deviation [SD] = 26.99). The average volume of the PAP flap was 31.73 cm3 (SD = 26.12). The average total volume captured by the chimeric gracilis and PAP flap was 101.94 cm3 (SD = 62.40). The potential soft tissue volume that can be harvested from a chimeric gracilis and PAP flap is significantly greater than solitary gracilis or PAP flaps. This chimeric flap may serve as a viable and advantageous reconstructive option for patients requiring large volume soft tissue coverage, particularly if other sizable options are not available.

3D extraoral morphometric changes after implant surgery: an exploratory pilot study using stereophotogrammetry.

This pilot study aimed to evaluate, for the first time, the changes in facial tissues following the placement of a single dental implant. Patients were scanned with a 3D facial scanner (3dMD) before implant surgery, immediately after surgery (T1), at 7 days postoperatively (T2), and at the impression stage (T3). Acquired images were processed using the 3dMDvultus (3dMD) software program and volume differences and linear depth measurements were calculated to determine the morphometric changes over time. A total of 11 patients were included in the analyses. Descriptive statistics were employed to analyze the data. The volumetric changes and maximum depth differences indicated an initial increase, followed by a progressive decrease in tissue volume after implant placement in the area of the surgery. The volume change values ranged between 2.5 and 3.9 cm3 for T1, whereas for T2, the volume change decreased to a range of 0.8 to 1.8 cm3. Maximum depth differences ranged between 2.06 and 2.80 mm in the soft tissues immediately after the implant surgery and reduced to around 2.01 to 0.55 mm at the impression stage. The amount of painkiller used was not related to the magnitude of linear depth measurements at any assessed time point. There was a longitudinal decrease in soft tissue volume and depth difference in extraoral soft tissues in the region of implant placement after surgery up to 6 weeks. The use of a facial scanner is a promising noninvasive method to monitor 3D morphometric changes after implant surgery.

Cellularized Biomaterials Used as Gingival Connective Tissue Substitutes In Vivo: A Systematic Review.

Developing an in vitro model of gingival connective tissue that mimics the original structure and composition of gingiva for clinical grafting is relevant for personalized treatment of missing gingiva. Using tissue engineering techniques allows bypassing limitations encountered with existing solutions to increase oral soft tissue volume. This review aims to systematically analyze the different currently existing cellularized materials and technologies used to engineer gingival substitutes for invivo applications. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed. An electronic search on PubMed, Scopus, Web of Science, and Cochrane Library databases was conducted to identify suitable studies. In vivo studies about gingival substitutes and grafts containing oral cells compared with a control to investigate the graft remodeling were included. Risk of bias in the included studies was assessed using the Systematic Review Center for Laboratory animal Experimentation (SYRCLE) 10-item checklist. Out of 631 screened studies, 19 were included. Animal models were mostly rodents, and the most used implantation was subcutaneous. According to the SYRCLE tool, low-to-unclear risk of bias was prevalent. Studies checked vascularization and extracellular remodeling up to 60 days after implantation of the cellularized biomaterial. Cells used were mostly fibroblasts and stem cells from oral origin. Grafts presenting vascularization potential after implantation were produced by tissue engineering technologies including cell seeding or embedding for 14, cell sheets for 2, microsphere for 1, and extrusion 3D bioprinting for 2. Components used to build the scaffold containing the cells are all naturally derived and are mainly fibrin, gelatin, collagen, agarose, alginate, fibroin, guar gum, hyaluronic acid, and decellularized extracellular matrix. The most recurring crosslinking method was using chemicals. All studies except one reported vascularization of the graft after implantation, and some detailed extracellular matrix remodeling. Current solutions are not efficient enough. By assessing the relevant studies on the subject, this systematic review showed that a diversity of cellularized biomaterials substituting gingival connective tissue enables vascularization and extracellular remodeling. Taking the results of this review into account could help improve current bio-inks used in 3D bioprinting for invivo applications compensating for gingival loss.

Long-term Follow-up of Implant Installation Following Multiple Distraction Osteogenesis in Maxillofacial Gunshot Wounds.

Distraction osteogenesis (DO) is a reconstruction technique developed in the fields of oral and maxillofacial surgery and plastic surgery, addressing both vertical and horizontal bone deficiencies and enhancing soft tissue volume to facilitate subsequent dental implant placement. In this treatment method, devices are placed to stretch the bone gradually to stimulate the formation of new bone, effectively filling the existing defect to treat maxillofacial deformities or repair posttraumatic injuries. This case report presents an almost 20-year long-term follow-up of jaw defect reconstruction resulting from a gunshot injury, using DO with multiple distractors. Details on the frequency, period of DO, and subsequent implant installation in the distracted anterior jaw area are outlined. This case exhibits DO treatments that reconstructed effectively severe bone defects in the jaws. The quality of bone generated during the DO process was both functionally and esthetically satisfactory for subsequent implant rehabilitation.

Association Between Soft Tissue Measures From Computed Tomography and Upper Airway Collapsibility on Drug-Induced Sleep Endoscopy.

Positive airway pressure (PAP) titration during drug-induced sleep endoscopy (DISE) provides objective measures of upper airway collapsibility. While skeletal measurements relate to collapsibility measures on DISE, the influence of soft tissue dimensions on upper airway collapsibility is not known. We analyzed the relationship of measures of upper airway soft tissue volumes, specifically soft palate, pharyngeal lateral walls, and tongue, with metrics of collapsibility. Cross-sectional analysis from a prospective cohort. Academic medical center. Patients seeking PAP alternative therapies for obstructive sleep apnea (OSA) underwent standardized supine computed tomography (CT) acquisition and DISE protocols. The CT analysis primarily focused on soft tissue volumes and, secondarily, on airway and skeletal volumetric measures. DISE with PAP administration (DISE-PAP) enabled the determination of the pressure at which inspiratory airflow first commenced (pharyngeal critical pressure, PcritA) and the pressure at which inspiratory flow limitation was abolished (pharyngeal opening pressure, PhOP). Both unadjusted and adjusted correlation analyses were performed to understand the relationship between upper airway anatomy and either PcritA or PhOP. One hundred thirty-nine subjects completed both CT and DISE-PAP. On average, patients were male (70.5%), white (84.2%), middle-aged (56.6 ± 13.5 years), and overweight (29.6 ± 4.7 kg/m2), with moderate-severe apnea-hypopnea index (29.7 ± 21.3 events/h). Adjusted for age, sex, body mass index, and skeletal volumes, soft palate, and lateral pharyngeal wall volumes were not associated with PhOP or PcritA, but a larger tongue was associated with more positive PhOP (⍴ = 0.20, P = .02), and more positive PcritA (⍴ = 0.16, P = .07). Exploratory analyses revealed smaller minimum cross-sectional retropalatal area and intramandibular volume were also associated with increased collapsibility measures. After controlling for clinical factors and skeletal volume, greater tongue volume was associated with more severe collapsibility during DISE. These results, in concert with previous work, suggest that greater tongue volume in a smaller skeletal dimensions contribute to the severity of airway collapsibility, a key driver of OSA pathogenesis.

Progress of Degradable Synthetic Polymers in Adipose Tissue Engineering-A Review

Breast cancer stands as the foremost prevalent malignancy affecting women worldwide. The restoration of soft tissue volume is often necessary in cases of soft tissue loss, such as burn defects, surgical area defects, or posttumor resection defects, particularly in breast cancers. Conventional surgeries interventions, such as flap transplantation, can result in various complications and malformations, while prosthesis implantation may not be suitable due to skin weakness caused by radiation therapy. Autologous fat transplantation to the breast exhibits limited efficacy due to the unpredictable of resorption and low graft survival rates. Tissue engineering has emerged as a promising field offering novel therapeutic possibilities in regenerative medicine over the past two decades. Extensive exploration has been conducted on synthetic materials for adipose tissue engineering applications. This review delineates the current advancements and future directions in adipose tissue engineering strategies, cell applications, adipogenesismechanisms, and key factors, while focusing on the utilization of degradable synthetic polymers and the integration of 3D printing technologies.

Treatment of Bisphosphonate-related Osteonecrosis of Jaw (BRONJ) in Rabbit Model: A Proof-of-concept Animal Study Comparing Angiogenesis Factor Versus Autologous Bone Marrow-derived Osteoblasts (ABMDO)

Objective We created Bisphosphonate-related Osteonecrosis of Jaw (BRONJ) in rabbits and treated them with an angiogenesis factor or autologous bone marrow derived osteoblasts (ABMDO) to assess the efficacy of the treatment by Micro-computerized Tomography (M-CT) and histopathology. Materials and Methods Thirty female New Zealand rabbits were procured and were divided into three groups of 10 animals each. The number of animals to achieve statistical significance was based on the reported studies. Group I was control group (C), Group II was Osteoblast group (O), and Group III was angiogenesis group (P). In all Groups, BRONJ was produced. At 8 weeks of tooth extraction, BRONJ was confirmed histologically and radiologically in two rabbits from each group of animals. Group I received 0.5 of normal saline, Group II received a single dose of 5 million osteoblasts suspended in 0.5 ml, and Group III received 5 mg of angiogenesis factor thrice weekly for three weeks. The healing of BRONJ was assessed using M-CT and histopathology. Results In O and P groups, the extraction sockets healed and closed with normal-looking tissue, whereas in the C (control) group, suppuration with an area of necrosis was observed. Micro-CT analysis of socket revealed an exaggeration on non-mineralized soft tissue volume in the C group, whereas most of the bone promotion parameters were improved in the O and P groups with statistical difference (P<0.001) for the parameters bone volume, bone surface area, trabecular number and trabecular thickness. Histologically, the element of healing was represented by reactive bone formation and fibrosis, which were more prominent in groups O and P as compared to the control group. Conclusion Our study shows that ABMDO and angiogenesis factor have a robust potential to heal BRONJ. Clinical Relevance The study shows angiogenesis factor and osteoblasts heals BRONJ and warrant sincere human trials to tackle this unrelenting complication of bisphosphonates use.

Histological and immunohistochemical analysis of autografts and xenografts synergy in rectifying attached keratinized gingiva deficiency

Relevance. The complex, multi-stage surgical procedure aimed for replacing missing teeth often results in a deficiency of attached keratinized gingiva (AKG) in the intervened area. Despite numerous methods available for soft tissue volume and esthetics reconstruction, only a few demonstrate considerable long-term stability post-surgery. The quest to address this intricate issue has led to the combined utilization of autografts and xenografts Consequently, there is a need to evaluate the tissue structure obtained through this synergy via histological and immunohistochemical examination of the oral mucosa in the reconstructed region.Materials and methods. This study involved analyzing 87 biopsies of oral mucosa obtained from 57 patients aged 28 to 59 years who had undergone previous soft tissue volume and esthetics reconstruction in the AKG zone. Histological and immunohistochemical examinations were conducted on these biopsies, collected six weeks post soft tissue operation. A section of oral mucosa from the hard palate served as the reference sample.Results. The epithelial structure in the examined groups exhibited a well-defined basal layer with a continuous structure comprising two layers of cells without notable atypia, indicating a high cell proliferation capability. Immunohistochemical analysis targeting protein molecules revealed an absence of inflammation. The expression results of the Ki-67 antigen suggested the preservation of cell proliferation capacity and, consequently, the maintenance of tissue regenerative potential at a high level during the remote postoperative period, up to six weeks.Conclusion. This research showcases the efficacy of employing a combination of autografts and xenografts, a conclusion drawn from comprehensive histological and immunohistochemical analyses. Consequently, this approach presents a promising and innovative alternative to conventional methods for soft tissue volume and esthetics reconstruction.

Effect of Customized and Prefabricated Healing Abutments on Peri-Implant Soft Tissue and Bone in Immediate Implant Sites: A Randomized Controlled Trial

This study aimed to evaluate the effect of customized healing abutments compared to prefabricated healing abutments in immediate implant sites. Twelve patients requiring single immediate implant placement were divided into two groups: a prefabricated group received prefabricated titanium healing abutments, and a customized group received a polyetheretherketone (PEEK) customized healing abutments fabricated based on the individuals’ digital impressions. Outcomes, including peri-implant horizontal and vertical soft tissue alteration, bone level change, volume change, pain score, and pink esthetic score (PES) change, were evaluated at the 1-, 4-, and 6-month follow-ups compared to pre-extraction teeth. At the 1- and 4-month follow-ups, the customized group had a significantly lower buccal volume variation (BVv). At the 6-month follow-up, neither group showed any significant difference in the marginal bone change; however, the customized group had a significantly lower PES change and a lower pain score. In the anterior and premolar regions, the customized group showed the preservation of peri-implant buccal horizontal soft tissue and buccal volume, while in the molar regions, the preservation of papilla height and midfacial height was observed. The morphology of the customized healing abutment demonstrated a better trend in preservation of peri-implant soft tissue, esthetic outcomes, and lower patient discomfort in immediate implant sites.

Utilizing a Second Flap to Address the Effect of Postradiotherapy Soft Tissue Fibrosis in Head and Neck Malignancy.

Background Late effects of adjuvant radiation therapy (RT) on soft tissues can lead to hair loss, pigmentary changes, loss of tissue volume, and fibrosis, which appear months to years after the treatment. These changes are often progressive and are because of tissue hypoxia due to radiation-induced capillary endothelial damage. Tissue hypoxia may be compounded by subclinical infection following minor trauma, exposed hardware, or associated osteoradionecrosis. The combined effect of these factors causes significant deformities in soft tissue, affecting both function and appearance. Such changes are also seen in primarily transferred flaps, which have been radiated, resulting in severe, progressive soft tissue fibrosis, compromising function and aesthetics. In selected cases, a second flap may be needed to restore function and volume. Methods Data of patients who underwent secondary soft tissue transfers for postradiotherapy-related soft tissue changes were collected from the hospital electronic medical records, from January 2019 to 2023. Details regarding the primary surgery, dose, duration of adjuvant RT, time interval between adjuvant RT and secondary soft tissue transfer, indications, and the choice of the second flap were analyzed. Results Twenty-one patients had undergone secondary soft tissue transfer for extensive soft tissue fibrosis. In addition, associated compounding features like exposed implant and volume loss were observed. Two patients with osteoradionecrosis also had associated extensive soft tissue fibrosis necessitating replacement. Out of these 21 patients, 13 had undergone free tissue transfers, while 7 locoregional tissue transfers. Conclusion Late sequelae of adjuvant RT changes usually present from 6 months onwards. The radiated hypoxic tissue, due to capillary damage, leads to a chronic progressive fibrotic stage, causing loss of soft tissue volume and fibrosis. Replacing this tissue with a vascularized flap helps to restore volume and correct these secondary changes, improving overall quality of life.

Three-dimensional soft tissue reconstruction and volume measurement used for the diagnosis of dysthyroid optic neuropathy.

Dysthyroid optic neuropathy (DON) leads to vision loss. This study aimed to investigate a new method that can directly evaluate the change in muscle cone inner volume (MCIV) and distinguish DON orbits from non-DONs. This study included 54 patients (108 orbits) who were diagnosed with thyroid eye disease and treated at the Beijing Tongren Hospital between December 2019 and September 2021. The extraocular muscle volume (EOMV), orbital fat volume (OFV), and bony orbit volume (BOV) of the patients were measured using three-dimensional reconstruction. MCIV was measured using artificially defined boundaries. The associations between these volumes and clinical indicators were studied, and the diagnostic efficacy of these volumes for DON was described using receiver operating characteristic (ROC) curves. The ROC curve showed that the area under the curve of MCIV/BOV (%) combined with EOMV/BOV (%) reached 0.862 (p < 0.001), with a sensitivity of 85.7% and a specificity of 76.1%. The combination of MCIV/BOV (%) and EOMV/BOV (%) is a good indicator for the diagnosis of DON, which aids in the early detection and intervention of DON.

Impact of long-term nasal airflow deprivation on sinonasal structures and chronic rhinosinusitis in total laryngectomy patients.

Total laryngectomy (TL) patients are good models in which to evaluate the effects of nasal airflow cessation on the sinonasal tract. Here, we evaluated changes in sinonasal structures and association with sinus opacification in the computed tomography (CT) images 3 years post-TL. Patients who underwent TL from 2005 to 2017 in a teaching academic center were reviewed retrospectively. Patients with a final follow-up CT taken less than 3 years after TL, tracheoesophageal puncture, inadequate CT image, or history of sinonasal surgery were excluded. The control group included patients who underwent a partial laryngectomy or hypopharyngectomy without requiring a tracheotomy for more than a month. Altogether, 45 TL patients and 38 controls were selected. The volume of all four paranasal sinuses, inferior turbinate soft tissue volume (ITSTV), maxillary sinus natural ostium (MSNO) mucosal width, and Lund-Mackay scores (LMS) were measured on preoperative and postoperative CT scans. The mean duration between surgery and the final CT scan was 6.3 ± 2.4 and 5.5 ± 2.3 years for the TL and control groups, respectively. Neither group showed significant changes in the four paranasal sinuses' volume or MSNO mucosa width. The ITSTV decreased significantly, from 4.6 ± 1.3 to 2.8 ± 1.1 mL (p < .001), in the TL group, regardless of the presence of nasal septal deviation, showing ITSTV reduction on both concave and convex sides. By contrast, the control group showed no significant changes in ITSTV. Postoperative LMS changes in both groups were insignificant. The number of patients with LMS aggravation or alleviation was the same in both groups, regardless of preoperative sinus opacification. Paranasal sinus structures and sinus opacification are not affected significantly by nasal airflow cessation; however, the inferior turbinate mucosa is affected by long-term discontinuation of nasal airflow. 4 (case-control study).

A new lymphedema treatment using pyro-drive jet injection.

Lymphedema, resulting from impaired lymphatic drainage, causes inflammation, fibrosis and tissue damage leading to symptoms such as limb swelling and restricted mobility. Despite various treatments under exploration, no standard effective therapy exists. Here a novel technique using the pyro-drive jet injection (PJI) was used to create artificial clefts between collagen fibers, which facilitated the removal of excess interstitial fluid. The PJI was used to deliver a mixture of lactated Ringer's solution and air into the tail of animals with secondary skin edema. Edema levels were assessed using micro-CT scanning. Histopathological changes and neovascularization were evaluated on the injury-induced regenerative tissue. Regarding tissue remodeling, we focused on connective tissue growth factor (CTGF) and vascular endothelial growth factor (VEGF)-C. PJI markedly diminished soft tissue volume in the experimental lymphedema animals compared to the non-injected counterparts. The PJI groups exhibited a significantly reduced proportion of inflammatory granulation tissue and an enhanced density of lymphatic vessels and α-smooth muscle actin (αSMA)-positive small vessels in the fibrous granulation tissue compared to the controls. In addition, PJI curtailed the prevalence of CTGF- and VEGF-C-positive cells in regenerative tissue. In a lymphedema animal model, PJI notably ameliorated interstitial edema, promoted lymphatic vessel growth, and bolstered αSMA-positive capillaries in fibrous granulation tissue. PJI's minimal tissue impact post-lymph node dissection indicates significant potential as an early, standard preventative measure. Easily applied in general clinics without requiring specialized training, it offers a cost-effective and highly versatile solution to the management of lymphedema.

The possibilities of additive technologies for targeted tissue regeneration and implantation in a patient with a mandibular defect. A clinical case

After injury or removal of neoplasms, bone, soft tissue scar defects and deformities are formed. Methods of reconstructive bone surgery do not reliably allow to restore defects in full. The main problem is constriction, subsequent atrophy and deformation of soft tissues in the defect area. Dental implant-prosthetic rehabilitation in the area of significant bone defects requires the use of design and prototyping of the final result using computer programs and diagnostic models. The clinical experience of using an individual temporary endoprosthesis, a «tissue expander» made by layer-by-layer synthesis (3D printing) of biologically inert plastic according to CT data of the patient is presented. The expander is made in the form of a 3D element for the formation of the necessary volume of soft tissues in the patient for a period of 2–4 months, fixed under the periosteum, in the area of the lateral defect of the lower jaw with intraosseous screws. Dental implants are installed in front. Intraoperative direct prosthetics was performed. A temporary screw prosthesis is installed in the mouth. After 3 months, 3 implants were installed and bone grafting was performed. Final prosthetics 7 months after the start of treatment.

Soft-tissue volume augmentation using a connective tissue graft and a volume-stable collagen matrix with polydeoxyribonucleotide for immediate implant placement: a pilot study in a dog model.

The aims of this study were 1) to investigate the effects of a subepithelial connective tissue graft (SCTG) and a volume-stable collagen matrix (VCMX) on soft-tissue volume gain in the immediate implant placement protocol, and 2) to determine whether polydeoxyribonucleotide (PDRN) can enhance the effects of a VCMX. Dental implants were placed in 4 mongrel dogs immediately after extracting the distal roots of their third and fourth mandibular premolars. The gap between the implant and the buccal bone plate was filled with synthetic bone substitute particles. The following soft-tissue augmentation modalities were applied buccally: 1) control (no augmentation), 2) SCTG, 3) VCMX, and 4) VCMX/PDRN. After 4 months, histomorphometric analysis was performed. Tissue changes were evaluated using superimposed standard tessellation language (STL) files. Wound dehiscence was found in more than half of the test groups, but secondary wound healing was successfully achieved in all groups. Histomorphometrically, tissue thickness was favored in group SCTG at or above the implant platform level (IP), and group SCTG and the groups with VCMX presented similar tissue thickness below the IP. However, the differences in such thickness among the groups were minor. The keratinized tissue height was greater in group VCMX/PDRN than in groups SCTG and VCMX. Superimposing the STL files revealed a decrease in soft-tissue volume in all groups. Wound dehiscence after soft-tissue volume augmentation might be detrimental to obtaining the expected outcomes. PDRN appears not to have a positive effect on the soft-tissue volume gain.

A Multicenter Pilot Study of a Novel Allograft Adipose Matrix in Malar and Prejowl Volume Restoration.

Allograft adipose matrix (AAM) offers a novel, off-the-shelf, and readily available natural option in the treatment of facial soft tissue volume and reconstructive deficits. AAM is a natural soft tissue supplement or replacement that can support cushioning and volume correction. A prospective multicenter pilot study evaluated AAM in facial volume restoration. Eleven women (mean age of 55.8 ± 10.9 y) with midface volume deficit were followed up for 24 weeks after AAM treatment in this institutional review board-approved multicenter pilot study. The clinical safety and efficacy of the AAM treatment were evaluated using clinical scales and three-dimensional quantitative facial photography. AAM was safe to address facial volume deficits, with minor site-related adverse events and discomfort that resolved within 2-4 weeks. Observations also revealed facial volume improvements throughout the study with 91% positive responders. At week 24, the subject facial satisfaction scores revealed an 86% increase compared to baseline, along with a statistically significantly improved midface fullness compared to baseline. AAM offers a natural and safe option for midface volume restoration and supports overall satisfaction and volume improvements.

Experimental assessment of diffusible iodine-based contrast-enhanced computed tomography (diceCT) protocols.

Diffusible iodine-based contrast-enhanced computed tomography (diceCT) is an increasingly used digital complement, supplement, or alternative to traditional dissection-based anatomical research. The diceCT protocol, which has evolved and expanded over the past decade, employs passive diffusion of Lugol's iodine (KI3) to increase soft tissue radiodensity and improve structure contrast in the CT or microCT imaging of specimens. The development and application of diceCT has focused largely on specimens under 1 kg, and the varying reporting of methods on studies of both small and large specimens has initiated, but not yet established, an effective diceCT protocol for larger specimens based on monitored experiments of several fundamental variables (e.g., Lugol's iodine concentration, duration, and impacts of Lugol's iodine on tissues). In this study, we have experimentally assessed the efficacy of diceCT protocols for imaging whole-body specimens of the 1-4.5 kg Australian brushtail possum (Trichosurus vulpecula) using sequential CT imaging assessment across experimental conditions. We assessed the impact of varying Lugol's iodine concentration, the presence/absence of skin, solution volume and agitation on tissue radiodensity changes through weekly CT-based monitoring of tissue radiodensities over an 8-week experimental period. We have also quantified tissue volumetric changes across our experiment to assess the impact of diceCT applications on subsequent analyses of imaging datasets. Our results indicate that substantial changes in both soft-tissue radiodensity and soft-tissue volume occur within the first 28 days of Lugol's iodine treatment, followed by a slower rate of progressive soft-tissue radiodensity and volume changes across the experiment duration. Our results demonstrate the negligible benefit of skinning larger specimens to improve solution diffusion, and document significant soft-tissue volumetric changes with high concentration solutions (e.g., 10%) and long-duration exposure (e.g., beyond 5 weeks) that should guide individual diceCT protocol design and/or quantification and analysis for mammal specimens above 1 kg.

Periprosthetic Knee and Hip Infection — Is It Possible to Compare Treatment Outcomes?

Background. It is known that the outcomes of patients treatment with periprosthetic joint infection (PJI) are significantly influenced by the state of the patient’s body, the nature of the pathogen, the state of tissues in the area of the infectious focus and the treatment tactics. However, topographic and anatomical features of the blood supply to the knee and hip joints, as well as the volume of soft tissues, can affect the spectrum of pathogens, manifestations of the infectious process and, as a consequence, the effectiveness of treatment.&#x0D; The aim of the study was to conduct a comparative analysis of the somatic status of patients, the etiology of the infectious process and the effectiveness of treatment of PJI depending on its localization.&#x0D; Methods. A single-center retrospective study was conducted. The cases of 337 patients were studied — 119 patients with knee and 218 patients with hip PJI who underwent treatment with a two-stage technique during the period from 2007 to 2017. A comparative analysis of the PJI pathogens structure and concomitant pathology between patients with hip and knee PJI was carried out. The frequency of infection relief in the groups following the first stage was counted.&#x0D; Results. Recurrence was diagnosed four times more frequently in patients with hip PJI compared to knee PJI. Risk factors for recurrence were gram-negative pathogens, microbial associations, and fistulous forms of the infectious process. Localization of the infectious process in the hip area was associated with a statistically significant greater volume of blood loss during the prolonged debridement surgery.&#x0D; Conclusion. Recurrences of PJI occur more frequently in the hip area compared to the knee joint. Further analysis of critical factors in recurrence development is necessary for potential intervention.