Mucosal cyst aspiration in conjunction with maxillary sinus elevation: A clinical cohort study.

INTRODUCTION: Patients with mucosal cysts in the maxillary sinus require special consideration in patients who require implant therapy for the restoration when undergoing implant therapy for the restoration of the posterior maxillary dentition. Treatment strategies for these clinical situations remain controversial in the literature. Thus, this study seeks to describe a safe and effective therapeutic strategy for sinus augmentation in patients with pre-existing maxillary antral cysts. METHODS: A total of 15 patients and 18 sinuses were consecutively enrolled in this cohort study and underwent maxillary antral cyst treatment by needle aspiration and simultaneous maxillary sinus augmentation (MSA). During surgical procedures, threeimplants (Zimmer Biomet, Indiana, USA) were positioned in 11 sinuses and two implants (Zimmer Biomet, Indiana, USA) were positioned in 5 sinuses. RESULTS: Overall implant success and survival rates were 100% and 97.8%, respectively at 1 year and 5-year follow-ups. Crestal bone resorption averaged 0.3 ± 0.2 mm 5-year post-loading, showing bone stability. Implant survival rate at 5-year follow-up expressed predictability of the technique comparable to historical data when MSA was performed alone. Crestal bone resorption averaged 0.3 ± 0.2 mm 5 years post-loading and shows bone stability utilizing mucosal cyst aspiration with concomitant MSA procedures. Quality of life evaluation at 1-week post-op showed similar results to published historical data. In 81% (13 sinuses), the CBCT examination at 5-year follow-up showed no cyst reformation, in 19% (3 sinuses) cyst reformation was visible, but smaller in size when compared to the pre-op CBCT evaluation, and all the patients were asymptomatic. CONCLUSIONS: Maxillary sinus mucosal cyst aspiration with concomitant MSA, may be a viable option to treat maxillary sinus cyst.

Indications for implant-supported rehabilitation of the posterior atrophic maxilla: A multidisciplinary consensus among experts in the field utilising the modified Delphi method.

PURPOSE: To establish consensus-driven guidelines that could support the clinical decision-making process for implant-supported rehabilitation of the posterior atrophic maxilla and ultimately improve long-term treatment outcomes and patient satisfaction. MATERIALS AND METHODS: A total of 33 participants were enrolled (18 active members of the Italian Academy of Osseointegration and 15 international experts). Based on the available evidence, the development group discussed and proposed an initial list of 20 statements, which were later evalu-ated by all participants. After the forms were completed, the responses were sent for blinded ana-lysis. In most cases, when a consensus was not reached, the statements were rephrased and sent to the participants for another round of evaluation. Three rounds were planned. RESULTS: After the first round of voting, participants came close to reaching a consensus on six statements, but no consensus was achieved for the other fourteen. Following this, nineteen statements were rephrased and sent to participants again for the second round of voting, after which a consensus was reached for six statements and almost reached for three statements, but no consensus was achieved for the other ten. All 13 statements upon which no consensus was reached were rephrased and included in the third round. After this round, a consensus was achieved for an additional nine statements and almost achieved for three statements, but no consensus was reached for the remaining statement. CONCLUSION: This Delphi consensus highlights the importance of accurate preoperative planning, taking into consideration the maxillomandibular relationship to meet the functional and aesthetic requirements of the final restoration. Emphasis is placed on the role played by the sinus bony walls and floor in providing essential elements for bone formation, and on evaluation of bucco-palatal sinus width for choosing between lateral and transcrestal sinus floor elevation. Tilted and trans-sinus implants are considered viable options, whereas caution is advised when placing pterygoid implants. Zygomatic implants are seen as a potential option in specific cases, such as for completely edentulous elderly or oncological patients, for whom conventional alternatives are unsuitable.

Microbial Upcycling of Waste PET to Adipic Acid.

Microorganisms can be genetically engineered to transform abundant waste feedstocks into value-added small molecules that would otherwise be manufactured from diminishing fossil resources. Herein, we report the first one-pot bio-upcycling of PET plastic waste into the prolific platform petrochemical and nylon precursor adipic acid in the bacterium Escherichia coli. Optimizing heterologous gene expression and enzyme activity enabled increased flux through the de novo pathway, and immobilization of whole cells in alginate hydrogels increased the stability of the rate-limiting enoate reductase BcER. The pathway enzymes were also interfaced with hydrogen gas generated by engineered E. coli DD-2 in combination with a biocompatible Pd catalyst to enable adipic acid synthesis from metabolic cis,cis-muconic acid. Together, these optimizations resulted in a one-pot conversion to adipic acid from terephthalic acid, including terephthalate samples isolated from industrial PET waste and a post-consumer plastic bottle.

Staged Extra-Articular Deformity Correction in the Setting of Total Knee Arthroplasty.

Background: Extra-articular lower-leg deformities mandate unique considerations when planning total knee arthroplasty (TKA). Poor limb alignment may increase perioperative complications and cause early implant failure. This study reports on the safety and efficacy of staged, extra-articular deformity correction about the knee in the setting of osteoarthritis and TKA. Methods: A retrospective review was conducted from December 2007 to December 2019 identifying 30 deformities in 27 patients (average age: 52.7 years; range 31-74) who underwent staged surgical correction of extra-articular deformity in preparation for TKA. Patient demographics, surgical details, clinical and radiographic measurements, severity of knee arthritis, and complications were collected. Results: There were 17 femur and 12 tibia deformities. There was an average improvement of 14.7° of deformity measured in the coronal plane and 12.7° of deformity in the sagittal plane in the femur and 13.5° in the coronal plane and 10.3° in the sagittal plane in the tibia. Leg length discrepancies improved by 26 mm on average (1-100 mm). After an average 3.1-year follow-up, 12 out of 27 patients proceeded with primary or revision TKA. There were no cases of blood transfusion, nerve palsy, or compartment syndrome, and all patients achieved bony union. Conclusions: Staged, extra-articular deformity correction is a safe and effective approach to improve limb alignment in the setting of knee osteoarthritis and TKA.

Biocompatible α-Methylenation of Metabolic Butyraldehyde in Living Bacteria.

Small molecule organocatalysts are abundant in all living organisms. However, their use as organocatalysts in cells has been underexplored. Herein, we report that organocatalytic aldol chemistry can be interfaced with living Escherichia coli to enable the α-methylenation of cellular aldehydes using biogenic amines such as L-Pro or phosphate. The biocompatible reaction is mild and can be interfaced with butyraldehyde generated from D-glucose via engineered metabolism to enable the production of 2-methylenebutanal (2-MB) and 2-methylbutanal (2-MBA) by anaerobic fermentation, and 2-methylbutanol (2-MBO) by whole-cell catalysis. Overall, this study demonstrates the combination of non-enzymatic organocatalytic and metabolic reactions in vivo for the sustainable synthesis of valuable non-natural chemicals that cannot be accessed using enzymatic chemistry alone.

How to avoid intraoperative and postoperative complications in maxillary sinus elevation.

Maxillary sinus floor elevation, via the lateral approach, is one of the most predictable bone augmentation procedures performed in implant dentistry. but both intra- and postoperative complications can occur, and some of them are severe. Our aim is as follows: To review the pertinent literature on the topic, especially assessing the risk factors related to complications. To give clinical recommendations to minimize intra- and postoperative complications with the ultimate scope of improving the standard of clinical care and patient safety.

Overproduction of Native and Click-able Colanic Acid Slime from Engineered Escherichia coli.

The fundamental biology and application of bacterial exopolysaccharides is gaining increasing attention. However, current synthetic biology efforts to produce the major component of Escherichia sp. slime, colanic acid, and functional derivatives thereof have been limited. Herein, we report the overproduction of colanic acid (up to 1.32 g/L) from d-glucose in an engineered strain of Escherichia coli JM109. Furthermore, we report that chemically synthesized l-fucose analogues containing an azide motif can be metabolically incorporated into the slime layer via a heterologous fucose salvage pathway from Bacteroides sp. and used in a click reaction to attach an organic cargo to the cell surface. This molecular-engineered biopolymer has potential as a new tool for use in chemical, biological, and materials research.

Induced Membrane Technique Is Effective for the Management of Acute Traumatic Bone Loss in Both Diaphyseal and Metaphyseal Lower Extremity Fractures.

OBJECTIVE: To compare outcomes of Masquelet-induced membrane technique (IMT) in metaphyseal and diaphyseal fractures with acute bone loss. DESIGN: Retrospective cohort study. SETTING: Four Level 1 Academic Trauma Centers. PATIENTS/PARTICIPANTS: Patients acutely treated with IMT for traumatic lower extremity bone loss at 4 Level 1 trauma centers between 2010 and 2020. INTERVENTION: Operative treatment with placement of cement spacer within 3 weeks of initial injury followed by staged removal and bone grafting to the defect. MAIN OUTCOME MEASUREMENTS: Fracture union, infection, revision grafting, time to union, and amputation. RESULTS: One hundred twenty fractures met inclusion criteria, including 43 diaphyseal fractures (DIM) and 77 metaphyseal fractures (MIM). Demographic characteristics were not significantly different, except for age (DIM 34 years vs. MIM 43 years, P < 0.001). Union after treatment with IMT was 89.2% overall. After controlling for age, this was not significantly different between DIM (41/43, 95.3%) and MIM (66/77, 85.7%) ( P = 0.13) nor was the rate of infection between groups. There was no difference in any secondary outcomes. CONCLUSIONS: The overall union rate in the current series of acute lower extremity fractures treated with the induced membrane technique was 89%. There was no difference in successful union between patients with diaphyseal bone loss or metaphyseal bone loss treated with IMT. Similarly, there was no difference in patients with tibial or femoral bone loss treated with induced membrane. Defect size after debridement may be more prognostic for secondary operations rather than the limb segment involved or the degree of soft-tissue injury. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

A New PETase from the Human Saliva Metagenome and Its Functional Modification via Genetic Code Expansion in Bacteria.

The discovery and engineering of new plastic degrading enzymes is an important challenge in chemical biotechnology to enable transition to a more sustainable and circular plastics economy. This field has so far yielded a range of enzymes and microbial pathways for the recycling and valorization of plastic waste. New research from Uttamapinant et al. reports the discovery of a novel polyethylene terephthalate (PET) hydrolase from the human saliva metagenome that displays improved properties and catalytic performance over previously characterized PET hydrolases (PETases). The authors also demonstrate the site-specific incorporation of a photocaged unnatural amino acid, 2,3-diaminopropionic acid (DAP), which upon photodecaging enables covalent binding of DAP to the PET surface. Thus, this work highlights metagenomic datasets as an untapped source of new PET degrading enzymes and the chemical modification of PETases via genetic code expansion, enabling new biotechnologies for the circular plastics economy.

Engineering biology for sustainable 1,4-butanediol synthesis.

Over the past decade, numerous approaches have been taken to replace unsustainable chemical syntheses with green biosynthetic alternatives. In a landmark paper, Yim et al. utilised an in silico-to-in vivo workflow to enable the high-level bioproduction of the unnatural small molecule 1,4-butanediol in the bacterium Escherichia coli.

Bread waste - A potential feedstock for sustainable circular biorefineries.

The management of staggering volume of food waste generated (∼1.3 billion tons) is a serious challenge. The readily available untapped food waste can be promising feedstock for setting up biorefineries and one good example is bread waste (BW). The current review emphasis on capability of BW as feedstock for sustainable production of platform and commercially important chemicals. It describes the availability of BW (>100 million tons) to serve as a feedstock for sustainable biorefineries followed by examples of platform chemicals which have been produced using BW including ethanol, lactic acid, succinic acid and 2,3-butanediol through biological route. The BW-based production of these metabolites is compared against 1G and 2G (lignocellulosic biomass) feedstocks. The review also discusses logistic and supply chain challenges associated with use of BW as feedstock. Towards the end, it is concluded with a discussion on life cycle analysis of BW-based production and comparison with other feedstocks.

Explaining the black-box smoothly-A counterfactual approach.

We propose a BlackBox Counterfactual Explainer, designed to explain image classification models for medical applications. Classical approaches (e.g., , saliency maps) that assess feature importance do not explain how imaging features in important anatomical regions are relevant to the classification decision. Such reasoning is crucial for transparent decision-making in healthcare applications. Our framework explains the decision for a target class by gradually exaggerating the semantic effect of the class in a query image. We adopted a Generative Adversarial Network (GAN) to generate a progressive set of perturbations to a query image, such that the classification decision changes from its original class to its negation. Our proposed loss function preserves essential details (e.g., support devices) in the generated images. We used counterfactual explanations from our framework to audit a classifier trained on a chest X-ray dataset with multiple labels. Clinical evaluation of model explanations is a challenging task. We proposed clinically-relevant quantitative metrics such as cardiothoracic ratio and the score of a healthy costophrenic recess to evaluate our explanations. We used these metrics to quantify the counterfactual changes between the populations with negative and positive decisions for a diagnosis by the given classifier. We conducted a human-grounded experiment with diagnostic radiology residents to compare different styles of explanations (no explanation, saliency map, cycleGAN explanation, and our counterfactual explanation) by evaluating different aspects of explanations: (1) understandability, (2) classifier's decision justification, (3) visual quality, (d) identity preservation, and (5) overall helpfulness of an explanation to the users. Our results show that our counterfactual explanation was the only explanation method that significantly improved the users' understanding of the classifier's decision compared to the no-explanation baseline. Our metrics established a benchmark for evaluating model explanation methods in medical images. Our explanations revealed that the classifier relied on clinically relevant radiographic features for its diagnostic decisions, thus making its decision-making process more transparent to the end-user.

A New PETase from the Human Saliva Metagenome and Its Functional Modification via Genetic Code Expansion in Bacteria.

The discovery and engineering of new plastic degrading enzymes is an important challenge in chemical biotechnology to enable transition to a more sustainable and circular plastics economy. This field has so far yielded a range of enzymes and microbial pathways for the recycling and valorization of plastic waste. New research from Uttamapinant et al. reports the discovery of a novel polyethylene terephthalate (PET) hydrolase from the human saliva metagenome that displays improved properties and catalytic performance over previously characterized PET hydrolases (PETases). The authors also demonstrate the site-specific incorporation of a photocaged unnatural amino acid, 2,3-diaminopropionic acid (DAP), which upon photodecaging enables covalent binding of DAP to the PET surface. Thus, this work highlights metagenomic datasets as an untapped source of new PET degrading enzymes and the chemical modification of PETases via genetic code expansion, enabling new biotechnologies for the circular plastics economy.

Palladium Nanoparticles from Desulfovibrio alaskensis G20 Catalyze Biocompatible Sonogashira and Biohydrogenation Cascades.

Transition-metal nanoparticles produced by living bacteria are emerging as novel catalysts for sustainable synthesis. However, the scope of their catalytic activity and their ability to be integrated within metabolic pathways for the bioproduction of non-natural small molecules has been underexplored. Herein we report that Pd nanoparticles synthesized by the sulfate-reducing bacterium Desulfovibrio alaskensis G20 (DaPdNPs) catalyze the Sonogashira coupling of phenyl acetylenes and aryl iodides, and the subsequent one-pot hydrogenation to bibenzyl derivatives using hydrogen gas generated from d-glucose by engineered Escherichia coli DD-2. The formal hydroarylation reaction is biocompatible, occurs in aqueous media at ambient temperature, and affords products in 70-99% overall yield. This is the first reported microbial nanoparticle to catalyze the Sonogashira reaction and the first demonstration that these biogenic catalysts can be interfaced with the products of engineered metabolism for small molecule synthesis.

Triceps Surae Lengthening in Foot and Ankle Trauma: A Survey of OTA and AOFAS Members.

Background: The prevalence, indications, and preferred methods for gastrocnemius recession and tendo-Achilles lengthening-grouped as triceps surae lengthening (TSL) procedures-in foot and ankle trauma are supported by a scarcity of clinical evidence. We hypothesize that injury, practice environment, and training heritage are significantly associated with probability of performing adjunctive TSL in the operative management of foot and ankle trauma. Methods: A survey was distributed to members of the American Orthopaedic Foot & Ankle Society and the Orthopaedic Trauma Association. Participants rated how likely they would be to perform TSL at initial management, definitive fixation, and after weightbearing in the presence and absence of a positive Silfverskiöld test in 10 clinical scenarios of closed foot and ankle trauma. Results: A total of 258 surgeons with median 14 years' experience responded. Eighty-five percent reported foot and ankle fellowship training, 24% reported traumatology fellowship training, 13% both, and 4% no fellowship. Ninety-nine percent reported performing TSL with a median 25 TSL procedures per year, 72% open gastrocnemius recession, and 17% percutaneous tendo-Achilles lengthening). Across all scenarios, we observed low overall 8% probability with fair agreement (κ = 0.246) of performing TSL (range, 1% at initial management of an unstable Weber B bimalleolar ankle fracture with negative contralateral Silfverskiöld test to 29% at definitive fixation of tongue-type calcaneus fracture with positive contralateral Silfverskiöld test). Silfverskiöld testing significantly influenced TSL probability at all time points. University of Washington training (ß = 1.5, P = .007) but not trauma vs foot fellowship training, years in practice, academic practice, urban setting, or facility trauma designation were significantly associated with likelihood of performing TSL. Conclusion: Orthopaedic traumatology and foot and ankle surgeons report similar indications, methods, and low perceived propensity to use TSL in the management of foot and ankle trauma. We found that graduates of 1 fellowship training site were more likely to perform TSL in the setting of acute trauma potentially indicating the need for better scientific data to support this practice. Level of Evidence: Level V, therapeutic.

Noninvasive Soft Tissue Expansion Strips and Wound Complications After Total Ankle Arthroplasty.

BACKGROUND: Total ankle arthroplasty through the anterior approach (TAR-AA) is an increasingly popular treatment for ankle arthritis, but it carries a known risk for wound complications. Several products have been investigated to mitigate this risk; however, most are either costly or invasive. Noninvasive skin expansion strips (NSESs) were designed to transfer tension away from the incision and induce new skin growth at the edges of the strips. We hypothesize that postoperative application of NSESs will decrease unplanned clinic visits and wound complications after TAR-AA. METHODS: This is a prospective cohort study of 41 patients at a single institution (3 surgeons) treated with NSESs after undergoing TAR-AA. An additional 41 consecutive historical patients treated without NSESs were retrospectively included as a control group. Patients received application of NSESs in the operating room after routine wound closure and again 2 weeks postoperatively. No other changes were made to the surgeons' wound closure technique, immobilization, follow-up timing, or rehabilitation protocols. Primary outcomes included (1) additional clinic visit required for wound assessment or suture removal, (2) superficial wound complication, and (3) deep infection. RESULTS: Baseline demographics did not differ significantly from our 41 consecutively treated historical controls. Additional clinic visits for suture removal or wound evaluation were significantly lower for patients treated with NSESs (15%, 6 of 41) compared to the control group (49%, 20 of 41) (P = .001). There was also a significant difference in the superficial wound complication rate in the treatment group vs control group, 2% and 12%, respectively (P = .04). There were no deep infections in either group. CONCLUSION: Noninvasive skin expansion strips placed after TAR-AA with an anterior approach have the potential to decrease wound complications and unplanned clinic visits. Further high-volume or randomized studies are needed to clarify their cost effectiveness and effect on long-term outcomes. LEVEL OF EVIDENCE: Level II, prospective cohort study.

Radiographic protrusion of dental implants in the maxillary sinus and nasal fossae: A multidisciplinary consensus utilising the modified Delphi method.

The aim of the present study was to generate an international and multidisciplinary consensus on the clinical management of implant protrusion into the maxillary sinuses and nasal fossae. A total of 31 experts participated, 23 of whom were experts in implantology (periodontologists, maxillofacial surgeons and implantologists), 6 were otolaryngologists and 2 were radiologists. All the participants were informed of the current scientific knowledge on the topic based on a systematic search of the literature. A list of statements was created and divided into three surveys: one for all participants, one for implant providers and radiologists and one for otolaryngologists and radiologists. A consensus was reached on 15 out of 17 statements. According to the participants, osseointegrated implants protruding radiographically into the maxillary sinus or nasal fossae require as much monitoring and maintenance as implants fully covered by bone. In the event of symptoms of sinusitis, collaboration between implant providers and otolaryngologists is required. Implant removal should be considered only after pharmacological and surgical management of sinusitis have failed.

Mathematically Directed Single-Cut Osteotomy.

A mathematically directed osteotomy (MDO) is a surgical planning technique for correcting long bone deformities. Using a mathematically derived osteotomy plane, the single-cut correction simultaneously addresses angular deformity, axial malrotation, and minor shortening. This review describes an MDO's indications for use, defines its input and output variables, includes the required graphs for osteotomy planning, and provides intraoperative tips and tricks for successful execution. Finally, the authors present a digital MDO calculator to simplify the complex computations and allow for more precise planning.

Low Window Sinus Elevation Technique: Bone Gain and Postsurgical Discomfort. A Retrospective Case Series.

Recently, the Low Window technique was proposed to facilitate sinus augmentation and reduce postsurgical patient discomfort. It was shown to be both safe and effective. This case series evaluates the postsurgical discomfort of patients undergoing Low Window sinus augmentation, the bone gain achieved, and whether these factors correlate with the osteotomy area. Records of patients (n = 26) who underwent a sinus elevation using the Low Window approach (n = 34 interventions), followed by implant placement and prosthetic rehabilitation (n = 97 implants), were assessed retrospectively. The analyzed outcomes were the medial, middle, and lateral bone gain ≥ 9 months after augmentation; pain at 5 to 6 hours postsurgery, evaluated on a visual analog scale (VAS; 0 to 100); pain, swelling, and hematoma formation every day up to 7 days postsurgery, evaluated by VAS; implant and prosthetic success and survival rates; and rate of complications. The average follow-up time was 62.1 ± 14.9 months. No intraoperative sinus membrane perforations or other complications occurred. Medial, middle, and lateral bone gains were 10.1 ± 1.7 mm, 11.6 ± 0.8 mm, and 10.7 ± 0.9 mm, respectively. At the last follow-up, the implant success rate was 99%. Postsurgical VAS pain 5 to 6 hours postsurgery was 12.3 ± 8.0 and decreased significantly thereafter. Swelling prevalence was 29.4% at 1 day postsurgery, 20.6% at 2 days, and 2.9% the following day. No swelling was observed from day 4 onward. Prevalence of hematoma was 8.8% for 2 days postsurgery, 2.9% the day after, and no hematoma was observed thereafter. Only the osteotomy area correlated with immediate postsurgical pain, but not with other discomfort outcomes or with bone gain. Low Window sinus elevation might allow bone gain and medium-term implant and prosthetic success rates similar to that of other access window designs. Prospective, comparative studies are needed to investigate whether the technique is more advantageous than traditional approaches.