Complex Surgery Research Articles

Risk factors for benign uretero-enteric anastomotic strictures after open radical cystectomy and ileal conduit.

Radical Cystectomy (RC) is one of the most common and complex surgical procedures in urologic surgery, and benign ureteroenteric anastomosis strictures (UAS) are complications described in about 15% of patients undergoing RC with different urinary diversion (UD). The aim of this study is to evaluate and analyze risk factors related to the development of ureteral stenosis after RC. All consecutive patients who underwent RC with ileal conduit from December 2019 to December 2022 were included. According to the guidelines patients with hydronephrosis were investigates with CT-scan or Ultrasound and blood tests at 3-6-12 months and then early. UAS was confirmed with CT-scan and eventually treated with nephrostomies with (with or without descendent pyelography). Several potential risk factor releated to UAS were analyzed by univariate analysis including preoperative, intraoperative and postoperative variables. In total 116 patients were included. At 30 months mean follow up, 21 patients (19%) were diagnosed with UAS. Median time from RC to diagnosis of benign UAS was 6 months (IQR: 4-9). At the univariable analysis previous abdominal surgery (OR 13.5 CI 3.4-63.4, p < 0.001) had the strongest association with shorter time to stricture development and six-fold highest risk of UAS development (OR 6.41, IC 95%; 2.16-21.1, p < 0.001). Also, gender, age, body mass index, lower albumin serum level, higher fibrinogen serum level showed statistically significant association (p < 0.05). Patients with preoperative lower albumin serum level, lower albumin/fibrinogen ratio and higher fibrinogen level are more likely to develop UAS. Moreover, having a history of PAS significantly increases the risk of strictures formation.

Implantation of a sutureless aortic valve into the ring of a mechanical valve: an extreme solution for extreme cases.

Reoperations due to dysfunction of artificial mechanical aortic valves represent a complex and high-risk surgical procedure, particularly for elderly patients. In this report, we present a case of an 81-year-old female patient where, due to structural degeneration of the mechanical valve, an emergency surgical procedure was indicated. After the removal of the valve leaflets, a sutureless aortic valve was implanted within the mechanical ring. In our case, we demonstrate that such an approach is a safe alternative for high-risk patients, who cannot undergo percutaneous procedures. By reducing the duration of cardiopulmonary bypass and aortic clamping, the surgical outcomes and complication rates can be significantly improved.

Impact of pregnancy termination law reforms in Ireland on pregnancy termination rates in the setting of fetal congenital heart disease: A trend analysis.

Prior to 2019, termination of pregnancy (TOP) was unlawful in Ireland. We sought to examine the impact of legislative change on TOP for major congenital heart disease (CHD) and its effect on parental decision-making regarding the options of complex surgery, TOP, or palliative perinatal care. This was a trend analysis of second-trimester TOP for major CHD before and after the law reforms relating to pregnancy termination in Ireland. Retrospective data were collected on pregnancies complicated by major CHD at the largest tertiary referral obstetric center in Ireland from January 2017 to December 2023. Suspected CHD cases were referred to a dedicated fetal medicine/cardiology service. Major CHD was defined as an expected requirement for cardiac intervention in the first year of life. Genetic testing was performed where required, counseling was offered, and individualized care plans were developed. In a consecutive unselected cohort, 269 of 60 871 screened pregnancies fulfilled criteria for a diagnosis of major CHD. Major CHD was an isolated abnormality in 55% (147/269) of cases, while an extracardiac diagnosis was identified in 45% (162/269). TOP was chosen in 21% (16/76) of cases prior to legislative change and in 20% (39/193) of cases after legislative change (P = 0.158). The TOP rate was 8% (13/147) in isolated CHD cases, compared with 34% (42/122) in the setting of additional abnormalities (structural or genetic). We observed no difference in the rate of TOP for major CHD before and after TOP law reforms in Ireland on the grounds of fetal abnormality.

Comparative evaluation of Bailey manoeuvre of deep extubation with conventional awake extubation technique - A randomized clinical study

Background: Extubation is a critical procedure in anesthesia and critical care, often accompanied by complications, such as bucking, coughing, and hemodynamic instability, particularly after major surgeries. The Bailey manoeuvre, involving deep extubation with the i-gel laryngeal mask airway (LMA), may mitigate these issues. The study was planned to compare the hemodynamic effects and side effect profiles of conventional awake endotracheal extubation and exchange extubation with the i-gel LMA. Aims and Objectives: The study was designed to compare hemodynamic stress response and respiratory complication between the conventional extubation group and the following exchange extubation group. Materials and Methods: In a prospective, randomized, single-blinded controlled study, 60 patients undergoing surgery under general anesthesia were divided into two groups: Group T (awake extubation) and Group L (exchange extubation with the i-gel LMA). Hemodynamic parameters and side effects were recorded and analyzed. Results: Group L exhibited significantly lower heart rates, systolic and diastolic blood pressures, and mean arterial pressures at various time points post-extubation compared to Group T. The incidence of hypertension was significantly higher in Group T (90%) versus Group L (50%). Bucking and coughing less in the i-gel LMA exchange group compared to the standard endotracheal tube extubation group. Conclusion: Exchange extubation with the i-gel LMA offers better hemodynamic stability and a lower incidence of hypertension compared to conventional awake extubation. This technique may be particularly beneficial for high-risk patients and those undergoing complex surgeries.

Advances in beyond total mesorectal excision surgery: Behind the scenes

The management of locally advanced rectal cancer involving adjacent organs and extending beyond the surgical planes of total mesorectal excision has evolved over the past few decades both in terms of the effectiveness of preoperative treatments and surgical innovation. The use of a robotic platform is increasing, even in complex surgery such as pelvic exenteration together with the advantages of minimally invasive procedures. However, satisfactory surgical, oncological, and functional outcomes are achieved not only minimizing the impact of a demolitive surgery but also when a multidisciplinary specialized team focuses on experienced surgeons, mandatory rules of surgical oncology, appropriate medical treatments, accurate preoperative planning, and an acceptable quality of life.

Intraoperative Optical Coherence Tomography (OCT)-Guided Femtosecond Laser-Assisted Descemet Membrane Endothelial Keratoplasty (iFAD)

We describe retrospectively the indications and outcomes of nine patients who present with varying degrees of deep posterior stromal scarring or endothelial failure following deep anterior lamellar keratoplasty (DALK). These patients underwent a surgical strategy coined Intraoperative Optical Coherence Tomography Guided Femtosecond Laser-Assisted Descemet Membrane Endothelial Keratoplasty (iFAD). This strategy can be used to address suboptimal visual outcomes following primary DALK. Patients undergoing iFAD first had femtosecond laser-assisted trephination of the underlying posterior lamella using the liquid keratoplasty system on the Femto LDV Z8 platform (Zeimer Ophthalmic Systems AG, Port, Switzerland). A Descemet Membrane Endothelial Keratoplasty (DMEK) graft was subsequently transplanted in place of the removed lamella. Out of nine cases, major indications for seven included post-infective, blepharokeratoconjunctivitis (BKC) and deep stromal scarring related to stromal dystrophy. The remaining two had endothelial failure following primary DALK. The main benefits of this surgical approach are (1) Utilization of integrated real-time iOCT on the femtosecond laser platform allows for precise calibration of a wide range of vertical posterior trephination depths (96–329 microns) from the endothelial surface. (2) Femtosecond laser trephination utilizing a non-applanation liquid interface preserves trephination geometries and maximises precision-based surgical outcomes. (3) iFAD is a viable and straightforward technique for surgeons addressing patients who might otherwise require complex surgery to address residual deep stromal scars post-DALK.

Extraperitoneal Open Radical Cystectomy: A New Standard in Frail Patients with Muscle-Invasive Bladder Cancer?

Background/Objectives: Radical cystectomy (RC) represents one of the most complex and morbid surgical procedures in the field of Urology. Extraperitoneal open RC has emerged as an alternative to the traditional transperitoneal approach for the treatment of muscle-invasive bladder cancer. Frailty is one of the most important risk factors for perioperative morbidity and mortality, and this category of patients can benefit the most from the extraperitoneal approach. The purpose of this study was to evaluate the feasibility and the safety of extraperitoneal open RC in our experience; Methods: We retrospectively collected the data of 75 frail patients who underwent an extraperitoneal open RC, performed by a single experienced surgeon. We assessed their frailty status using the simplified frailty index (sFI). We recorded data regarding general characteristics, intraoperative, pathological, and postoperative complications, and mortality (within 90 days); Results: We analyzed 61 males and 14 females with an sFI equal to or higher than 3. The median age was 77 years. Fifty-one patients had an ASA score of 3 or more. Sixty procedures were with radical intention, while fifteen were palliative. Cutaneous ureterostomy was performed in 70 cases and extraperitonized ileal conduit in five cases. The median operative time was 150 min. The median blood loss was 400 mL. The median time to flatus was 2 days. The median postoperative stay was 7 days. Thirteen patients had Clavien-Dindo III or IV complications. Two patients died in first 90 days postoperatively; Conclusions: The extraperitoneal open RC in frail patients was demonstrated to be a feasible and safe alternative approach in definitive treatment or a palliative setting in our experience.

MÉTODOS DIAGNÓSTICOS PARA O TRATAMENTO DA ENDOMETRIOSE

Endometriosis is an inflammatory disease that affects around 10% to 15% of women of reproductive age and can be asymptomatic or present symptoms of great relevance affecting the woman’s social life. Thus, among the most reported manifestations, chronic abdominal pain, dysmenorrhea, dyspareunia, urinary and/or bowel movements symptoms and infertility stand out. Pelvic ultrasound and magnetic resonance imaging examinations may reveal consistent foci of endometrioma or deep infiltrative endometriosis. However, these imaging tests do not have the specificity necessary for the diagnosis of superficial peritoneal endometriosis. The measurement of the CA-125 marker is the most used laboratory test to investigate the disease. CA-125 is a blood protein that at high levels can be indicative of endometriosis, with a sensitivity of 75% sufficient to indicate the disease. However, the exam that presents a definitive diagnosis of endometriosis characterized by a gold standard procedure is laparoscopy and anatomopathological analysis, which consists of a risky and high-cost procedure, but of great importance in the diagnosis and treatment of the disease. Endometriosis is a chronic, benign and progressive disease, early diagnosis is extremely important to avoid further complications for women, such as highly complex surgery and infertility.

Current trends in types of pancreatoduodenectomy: Focus on the advancement of robot-assisted pancreatoduodenectomy with 630 consecutive cases.

Pancreatoduodenectomy (PD) is a complex abdominal surgery, and the adoption of robotic PD has been on the rise because of its numerous benefits. This study aimed to investigate the current PD trends, focusing on advancements in robotic surgery. Between 2015 and 2023, 1231 patients underwent open PD, whereas 630 underwent robot-assisted PD (RAPD). Demographics and surgical outcomes were analyzed according to the time period. Moreover, a propensity score-matched (PSM) analysis was performed to evaluate the clinical outcomes. The proportion of RAPD cases gradually increased from 6.3% in 2015 to 50.9% in 2020, reaching a plateau of >50% thereafter. The proportion of patients receiving neoadjuvant chemotherapy increased during the late period (11.4% vs. 17.6%), with many of these patients undergoing open PD. Additionally, RAPD was performed in patients with a high probability of postoperative pancreatic fistula. However, the two groups demonstrated no significant difference in the occurrence of clinically relevant postoperative pancreatic fistula (10.6% vs. 9.5%, p = .532). Among periampullary cancer cases, RAPD demonstrated comparable survival outcomes to open PD after PSM (5-year survival rate: 61.8% vs. 49.8%, p = .189). RAPD has become a stable approach, accounting for over 50% of all PD cases in high-volume centers, and it can be safely performed. However, open PD remains important owing to the development of neoadjuvant therapy and the aging population. Therefore, establishing appropriate indications to maximize the benefits of both RAPD and open PD is necessary.

Short-term Outcomes of a Dedicated Pelvic Exenteration Unit in a Tertiary Hospital in Malaysia

Background : Pelvic exenteration offers potentially curative resection for locally advanced pelvic malignancy. A dedicated unit performing this complex surgery is recommended to achieve optimal outcomes. Objectives : The aim of this paper is to show that pelvic exenterations can be performed with acceptable oncological and safe perioperative results in an appropriately resourced specialist centre. Methods : Patients undergoing pelvic exenteration in the Colorectal Unit, Hospital Kuala Lumpur between January 2017 and January 2024 were included. Patients operated in the initial setup period of the unit (January 2017 – July 2020) were compared to the second half (August 2020 – January 2024) with univariate analysis. Results : A total of 30 patients were included, with a significant increase in the unit caseload over the study period (n = 11 versus n = 19). There was an increased use of neoadjuvant therapy and an increase in stage of disease at presentation (p = 0.014) in the second half of the study period. More complex procedures were performed in the latter period, involving both bony and pelvic side wall resections. There was no difference in complication severity (Clavien Dindo) (p = 0.257) and R0 resection was achieved in 76.7% of operated cases. Conclusion : The development of a dedicated pelvic exenteration unit, leads to an increase in patient volume and an increase in the complexity of the procedures performed, without compromising short term outcomes and safety.

OGC SO09 - Embracing change: Reproducible protocol for enhanced recovery after esophagectomy

Abstract Background Esophagectomy for cancer of the oesophagus is a complex surgery with significant morbidity. Protocols have been proposed to enhance recovery and reduce morbidities after this surgery. A decade ago, we have introduced major changes to the traditional perioperative management of esophagectomy patients and have been able to introduce these changes and reproduce the same results in three different countries. Method While working in the NHS, the main author has introduced many changes in the perioperative management of esophagectomy patients. The major changes included: 1- Injection of 200 units of Botox into the pylorus in the week prior to surgery. 2- No use of thoracic epidural and use of intercostal block instead. 3- Hybrid minimally invasive esophagectomy(HMIO) (Laparoscopic abdominal part and right thoracotomy). 4- Use of Heimlich valve instead of under-water seal bottle. 5- Avoidance of Opiate use and walking the patient on day 1 postoperatively. These changes were introduced in two other countries namely; Egypt and Dubai. Results We studied 151 consequtive cases of esophagectomy from January 2014 till April 2024 (102 cases were performed in NHS Wales and 49 cases were performed in Egypt and Dubai). Median age was 69 and range of 38 - 83 years. 94% had adenocarcinoma and 88% were stage 2b -3b. Neoadjuvant chemotherapy were given to 91% of patients. All patients had the described changes applied. Overall complication rate is 17.2% with Clavien-Dindo score of ≥ 3a in 8%. Anastomotic leak and 90-day mortality were 2.6%. Median hospital length of stay is 5 days. There were no difference of outcomes in the three countries. Conclusion Preoperative injection of Botox into the pylorus, use of Heimlich valve instead of under-water seal bottle, use of intercostal block instead of thoracic epidural and avoidance of Opiate use when applied to HMIO significantly improve the short-term outcomes after esophagectomy. These changes and outcomes are reproducible.

OGC SO08 - Optimising Analgesia in Sub-total Oesophagectomy: A Dose of Success

Abstract Background Sub-total oesophagectomy (STO) is a complex and major surgery with significant associated burdens for our patients. Our centre in North-East England completes 70-80 STOs annually. In the peri-operative period, good analgesia management and delivery is key. Analgesia strategy has evolved across the UK over the past decade, influenced by multi-modal analgesia, progressing surgical approaches towards minimally invasive operations alongside the ongoing drive for enhanced recovery programmes endorsing early mobilisation. Surgical approach in our patient cohort now comprises a combination of Open-Open, combined Open-Minimally invasive and entirely minimally invasive techniques. Our analgesia strategy combines single shot intrathecal diamorphine and regional anaesthesia. Method We engaged our multi-professional (Acute Pain Specialist Nurses, Anaesthesia Consultants and Surgical Consultants) team in a PDSA cycle. A guidance analgesia package was agreed after review of retrospective cases. This package was delivered to our baseline group of 10 patients. We used subjective patient reported abdominal and thorax pain scores on a 0-10 scale, recorded by our pain team each day for post-operative days 1-5. Following analysis, we implemented a single change to Intrathecal diamorphine dosing - changing from uniform delivery of 1000micrograms intrathecal diamorphine to a dose calculated on Ideal Body Weight of 15-20micrograms/kg up to 1500micrograms maximum dose Results Our baseline group of 10 patients all received 1000micrograms of intrathecal diamorphine - mean dose 15.9mcg/kg. Our intervention group of 12 patients received doses based upon their ideal body weight - mean dose 18.9mcg/kg. Overall, there was a trend of reduced pain scores following our intervention. Thoracic reported overall pain scores were significantly lower (p=0.04) following the intervention. No significant difference was demonstrated specifically in the first 24 or 48hours in overall, abdominal or thoracic pain scores. Importantly, there were no reported adverse events related to our higher dosing regime and no recorded side effects such as pruritis or nausea. Conclusion There is little evidence with regards the use of higher dose intrathecal diamorphine in the literature. The sample sizes in our groups are small but overall reduction in patient reported pain scores appear to be associated with use of the higher dose of intrathecal diamorphine, based upon ideal body weight and importantly without any adverse effect. Continued evolution of our analgesia strategies is essential alongside that of surgical techniques. The next iterations of our guidance and PDSA cycle will consider our regional techniques to identify if further advances can be made.

Primary Nasosinus Melanoma: A Case Report

Naso-sinusal mucosal melanoma is a highly aggressive but uncommon tumor. It is often diagnosed late, making treatment complex (surgery and/or radiotherapy---), with a generally poor prognosis. The absence of an established etiological factor and a specific clinical appearance make diagnosis difficult at an early stage. This tumor frequently affects women, with a predilection for the 6th decade of life. In this articl, we report a new case of nasosinus melanoma.

BIOM-65. ELEVATED MMP9 EXPRESSION IN ADHERENT AND LARGE VESTIBULAR SCHWANNOMAS: A PROMISING THERAPEUTIC TARGET

Abstract Vestibular schwannoma (VS) is the most common tumor of the cerebellopontine angle affecting up to 1 in 2000 adults and presents significant treatment challenges, especially when the tumor is adherent to the brainstem and cranial nerves. These tumors often require complex surgeries with high risks of complications such as hearing loss, facial paralysis, and incomplete tumor resection. Previous studies have linked immune cell infiltration and protease activation to aggressive VS. MMP9, a protease involved in extracellular matrix (ECM) remodeling, is associated with cancer invasion and progression, suggesting its potential as a biomarker and therapeutic target. This study explores whether MMP9 can classify VS and improve surgical outcomes. METHODS Fresh tumors were collected from patients undergoing surgery to establish primary VS cultures. Transcriptomic profiling was performed to examine expression of genes related to ECM remodeling, protease activation, and immune cell infiltration. MMP9 expression during schwannoma progression was validated using immunofluorescence staining and ELISA. Transwell invasion assays were performed to evaluate the role of MMP9 in schwannoma invasion. The efficacy of small molecule inhibitors against eIF4F (a transcription factor that binds to 5’ UTR of MMP9) and against MMP9 was tested in a mouse model of schwannoma. RESULTS MMP9 was the most abundantly expressed protease in VS. MMP9 expression increased with tumor size, and was higher in adherent than non-adherent VS (49.7 vs. 13.8 ng/mL, p=0.014). MMP9 expression was abundant in perivascular regions in adherent VS. Inhibition of eIF4F reduced schwannoma cell invasion mediated by MMP9.MMP9 inhibition in vivo- reduced tumor burden by 50% in mice. CONCLUSIONS MMP9 is a highly active protease in VS growth and adherent VS. Developing MMP9-targeted therapies could be a breakthrough in managing these challenging tumors.

Biodegradable Stents: A Breakthrough in the Management of Complex Biliary Tract Injuries: A Case Report

Background and Clinical Significance: Biliary tract injuries are a recognized complication of laparoscopic cholecystectomy. Early diagnosis and prompt management are crucial to minimize complications such as bile leaks, strictures, and fistula formation. This case report highlights the use of a biodegradable biliary stent in managing a complex biliary injury and discusses the impact of delayed diagnosis on treatment outcomes. Case Presentation: We present the case of a 30-year-old male who sustained a Strasberg E2 biliary tract injury during a laparoscopic cholecystectomy. Initially misdiagnosed, the injury was only recognized on the fourth postoperative day. The patient underwent a Roux-en-Y hepaticojejunostomy and subsequently developed a postoperative biliary fistula, which was managed with percutaneous drainage. A biodegradable biliary stent was later placed to address a stricture and minimize the need for future interventions. One year later, the patient presented with symptoms of cholangitis, and radiological findings revealed a narrowing of the biliary lumen. The stricture was resolved and an endoscopic gastrojejunal shunt was placed to prevent further complications. The patient is currently in good condition with no signs of further complications. Conclusions: This case emphasizes the importance of early diagnosis in managing biliary tract injuries and highlights the potential of biodegradable stents to reduce the need for repeat interventions. Despite a delayed diagnosis necessitating complex surgical procedures, the use of a biodegradable stent proved effective in managing postoperative complications. Further studies are needed to evaluate the long-term efficacy of biodegradable stents in similar clinical scenarios.

Design of a Novel Macro-Micro Integrated Brain Surgery Robot Based on Modular Parallel Mechanisms

The advancement and development of medical surgical robots have provided new technological support for brain surgery and neurosurgical procedures, improving the reliability of highly complex and precise surgeries. In turn, this urges the design and development of novel surgical robots to possess higher precision, stability, and enhanced motion capabilities. In response to this practical demand, this paper introduces a macro-micro integrated medical brain surgery robot system based on the concept of modular PMs (parallel mechanisms), which have a total of 13 active DOFs (degrees of freedom). This system divides the motion process of brain surgery into a large-scale macro-motion space and a small-scale high-precision motion space for design and planning control. The introduction of the design concept that combines multiple modular parallel sub-mechanisms has brought a significant level of decoupling characteristics to the mechanism itself. A comprehensive introduction and analysis of the surgical robot are provided, covering aspects such as design, kinematics, motion planning, and performance indicators. To address the pose allocation and coordination of motion between the macro platform and the micro platform, a pose allocation algorithm based on the decoupling and non-decoupling characteristics in various dimensions of the macro-micro platform is proposed. The designed measurement experiments have demonstrated that the repeatability in positioning accuracy of the macro and micro platform reaches the level of micron and submicron respectively. Practical experiments of motion control and simulated brain electrode implantation validate the excellent performance and stability of the entire surgical robot system. This research contributes innovative insights to the development of medical surgical robot systems, particularly in the domain of mechanism design.

Penile inversion vulvo-vaginoplasty with scrotal graft for trans women: surgical technique and results of initial experience.

A significant proportion of trans women is demanding for a genital gender-affirming surgery, with vulvo-vaginoplasty being the most frequently requested procedure. The gold standard for primary vaginoplasty in trans women is the penile skin inversion technique with scrotal skin graft, which allows for increased depth of the vaginal cavity. The assessment of vulvo-vaginoplasty outcomes utilizing penile skin inversion and scrotal skin graft in individuals assigned male at birth in the surgeon's learning curve involves evaluating aesthetics, functionality, and sexual aspects. A total of 76 individuals assigned male at birth were included in 2 French university hospitals from 2020 to 2022. They underwent vulvo-vaginoplasty following 8 key steps: scrotal skin excision; bilateral orchiectomy; dissection between the rectum, bladder, and prostate; penile dissection; clitoroplasty; urethroplasty; penile skin inversion with scrotal skin graft; labioplasty. The average follow-up period was 12.4months, with participants averaging 35.7years of age. Each patient was invited to complete a questionnaire during follow-up. The study's outcomes encompassed the assessment of both early and late surgical complications, postoperative sexuality, aesthetic results, and voiding satisfaction. Of the total patients, 15.8% experienced major early postoperative complications, while 3% encountered major late postoperative complications. No complication was classified 4 or 5 in Clavien-Dindo scale. Most early complications were related to issues in vulvar healing, which did not compromise long-term aesthetic results. Patients-reported satisfaction was 82% after the procedure. Vulvo-vaginoplasty utilizing penile skin inversion and scrotal skin graft for individuals assigned male at birth is a reproductive surgery procedure that can be successfully performed by experienced urologist. It achieves high patient-reported satisfaction even during the learning curve. The surgical procedures were consistent, and the sizable cohort of patients accurately reflects the learning curve of both surgeons. However, extrapolating long-term complications is challenging due to the relatively brief follow-up period. Additionally, there is a lack of self-reported sexual function data, and the scales used to assess patient-reported quality of life and urinary satisfaction are not specifically validated for transgender patients. Vulvo-vaginoplasty utilizing penile skin inversion and scrotal skin graft for individuals assigned male at birth is a complex surgical procedure. It appears to be achievable by experienced urologists during their learning curve, resulting in similar functional and surgical outcomes, along with high patient satisfaction.

The Role of 3D Printing in Endodontic Treatment Planning: A Comprehensive Review.

This review aims to provide an overall picture of the three-dimensional (3D) printing contributions to endodontic practice in treatment planning and execution. The methodology entails a comprehensive literature review of the technological processes and 3D printing applications in the field. Some key findings show that 3D printing is highly effective in producing the right dental models for training, helps in complex surgeries, and supports the transition toward personalized therapies. The review reveals that 3D printing has many benefits but that the broader adoption of this technology faces issues, including high technical requirements, high costs, and the need for safety standards. The study concludes that although in the future some challenges need to be addressed, the potential of 3D printing in endodontics is enormous and this means that the treatment methods of dentistry could be more efficient and innovative.

A data density-based measure of dexterity for continuum robots and its comparative study

Abstract Continuum robot-based surgical systems are becoming an effective tool for minimally invasive surgery. A flexible, dexterous, and compact robot structure is suitable for carrying out complex surgical operations. In this paper, we propose performance metrics for dexterity based on data density. Data density at a point in the workspace is higher if the number of reachable points is higher, with a unique configuration lying in a small square box around a point. The computation of these metrics is performed with forward kinematics using the Monte Carlo method and, hence, is computationally efficient. The data density at a particular point is a measure of dexterity at that point. In contrast, the dexterity distribution property index is a measure of how well dexterity is distributed across the workspace according to desired criteria. We compare the dexterity distribution property index across the workspace with the dexterity index based on the dexterous solid angle and manipulability-based approach. A comparative study reveals that the proposed method is simple and straightforward because it uses only the position of the reachable point as the input parameter. The method can quantify and compare the performance of different geometric designs of hyper-redundant and multisegment continuum robots based on dexterity.

Evaluation of the Efficacy of the HaeNaem Zero Bone Loss Kit in Indirect Sinus Lift Using Osseodensification.

Aim The purpose of this study was to evaluate alveolar height at the antral floor following dental implant placement after an indirect sinus lift using osseodensification (OD) with the HaeNaem bur system. Materials and methods A total of 12 patients seeking implant rehabilitation in the maxillary posterior region were selected for the study. Preoperative cone beam CT (CBCT) was performed to measure the residual crestal bone height (RCBH). Patients with an RCBH of 6-8 mm were included in the study. The HaeNaem Zero Bone Loss bur kit was utilized to create an osteotomy site through OD, accompanied by a simultaneous indirect sinus lift. Postoperative CBCT was obtained after four months to assess the difference in bone height and implant stability following implant placement. Results In our study, we performed a comparison of the alveolar ridge height before and after the procedure among the study participants using a paired t-test. This analysis revealed statistically significant differences (p-value <0.01) between the measurements taken before and after the procedure, indicating that the intervention yields effective results. Conclusions Based on the results of this study, it can be inferred that the indirect sinus lift procedure utilizing the OD technique with the HaeNaem Zero Bone Loss bur kit presents an effective treatment alternative for cases with insufficient bone height in the posterior maxilla. This approach is particularly advantageous when considering the increased financial feasibility of treatment options or in situations where advanced and/or time-consuming complex surgeries are contraindicated.