Kern's six-step approach allows for meaningful implementation of an orthognathic surgery training course.

OBJECTIVES: This study investigated the effectiveness of simulation training in improving the confidence and competency of oral and maxillofacial surgery (OMS) residents in performing orthognathic surgery (OGS). METHODS: Kern's six-step approach was applied when designing the simulation training for OMS residents. The difficulties encountered by the residents when learning OGS were considered when designing the training program. A training course consisting of didactic sessions, hands-on training on three-dimensional training models, and an assessment tool was implemented for OMS residents. Improvement in the confidence and competence of OMS residents in performing OGS, fidelity of the three-dimensional models, and satisfaction with the course was evaluated. RESULTS: All OMS residents (10/10) completed the course. The perceived difficulty in learning OGS was mainly related to the manipulation of the jawbones. While there were improvements in the median confidence and competence scores (3/5 to 4/5), only the differences in competence were found to be statistically significant (p < 0.01, Wilcoxon signed-rank test). Improvements in confidence and competence did not correlate. The mean fidelity scores of both the maxillary and mandibular models were adequate at 3.2 out of 5. Overall, satisfaction with the course was high (5/5). CONCLUSIONS: The six-step approach provides a guided process for educators to formulate a training course directed toward the perceived needs of students. Targeted training can significantly enhance the students' competence. Greater efforts should also be put in place to allow simultaneous developments in the students' confidence along with their competence.

Total Wrist Replacement Outcomes in the Asian Pacific Population - A Single-Centre Result.

Background: Total wrist replacement (TWR) is rarely done in the Asia-Pacific region. The aim of this study is to report the surgical outcomes and experience of TWR in patients with advanced arthritis. Methods: This is a retrospective review of all TWR patients in the Department of Orthopaedics and Traumatology, Prince of Wales Hospital, Hong Kong, which is a university tertiary centre, from January 2004 to March 2023. Recorded demographic parameters include gender, age upon surgery, pathology, types of implants and follow-up period. The surgical outcome parameters include range of motion, grip strength, wrist function assessment, radiological and clinical complications and any related secondary operations. Postoperative X-ray and clinical notes were reviewed. All wrist function assessments were performed by specialised occupational therapists according to protocol. Results: The study included a total of 12 wrists of 10 patients, all Chinese-Asian, with a mean age of 61.4 years at surgery. Larsen grade V arthritis constituted 50% and grade IV 16.7% of the patients, amongst which 33% had volar subluxation. The mean follow-up period was 97.4 months (21-205 months). The mean grip strength was 64.2% of the unaffected side. The mean postoperative Disabilities of Arm, Shoulder and Hand (DASH) score was 41.12% and patient-rated wrist/hand evaluation (PRWE) score 18.0. Complication incidence was 16.67% for loosening, 8.3% for metallosis and 8.3% for infection. One patient required conversion to total wrist arthrodesis due to metallosis. No patient suffered from dislocation, periprosthetic fracture and infection. Conclusions: TWR is an effective and safe alternative to total wrist arthrodesis with comparable outcomes. Our series outcomes are satisfactory and in line with literature. With meticulous soft tissue release and balancing, volar subluxation can also be corrected and may not be a contraindication. Level of Evidence: Level IV (Therapeutic).

Validation of low-cost mobile phone applications and comparison with professional imaging systems for three-dimensional facial imaging: A pilot study.

PURPOSE: The objective of this study was to investigate the accuracies of three-dimensional (3D) facial scanning mobile phone applications as compared to professional 3D facial imaging systems. MATERIALS AND METHODS: A manikin head model was used as the subject for comparing six 3D facial imaging systems which comprised three professional 3D scanners (3dMDface, Artec Eva and Vectra H2) and three mobile phone applications (Bellus3D, ScandyPro and Hedges). For each system, five scans were taken to analyse (1) linear accuracy using 9 measurements (2) global and (3) regional 3D accuracy of the scanned surface by root mean square (RMS) and colour map analysis. Another set of five scans was repeated by a second operator to evaluate the inter-operator reproducibility for each system. RESULTS: All the facial imaging systems had absolute errors lesser than 1.0 mm for the linear measurements. The technical error of measurement (TEM) for inter-examiner and intra-examiner linear measurements were within acceptable limits. Artec Eva, Vectra H2 and Scandy Pro had poor global 3D trueness (RMS > 1.0 mm) but good 3D regional trueness (RMS < 1.0 mm). 3dMDface, Bellus3D Face App and Heges had good global and regional 3D trueness. All the facial imaging systems had good global and regional 3D precision and reproducibility (RMS < 1.0 mm). CONCLUSION: This study demonstrated that mobile phone 3D scanning applications had comparable trueness, precision and reproducibility to professional systems. Colour map analysis supplemented the use of the RMS value to demonstrate facial regions of significant deviation. Clinicians should also consider the specific area or region of inaccuracies for each system to determine whether the chosen system is appropriate for the clinical condition or procedure. CLINICAL SIGNIFICANCE: Mobile phone 3D facial imaging applications may be as accurate as 3D professional facial scanning systems for craniomaxillofacial purposes. However, the choice of the system may vary depending on the specific area of interest.

Mapping out the surgical anatomy of the lingual nerve: a systematic review and meta-analysis.

Objectives: Understanding the lingual nerve's precise location is crucial to prevent iatrogenic injury. This systematic review seeks to determine the lingual nerve's most probable topographical location in the posterior mandible. Materials and Methods: Two electronic databases were searched, identifying studies reporting the lingual nerve's position in the posterior mandible. Anatomical data in the vertical and horizontal dimensions at the retromolar and molar regions were collected for meta-analyses. Results: Of the 2,700 unique records identified, 18 studies were included in this review. In the vertical plane, 8.8% (95% confidence interval [CI], 1.0%-21.7%) and 6.3% (95% CI, 1.9%-12.5%) of the lingual nerves coursed above the alveolar crest at the retromolar and third molar regions. The mean vertical distance between the nerve and the alveolar crest ranged from 12.10 to 4.32 mm at the first to third molar regions. In the horizontal plane, 19.9% (95% CI, 0.0%-62.7%) and 35.2% (95% CI, 13.0%-61.1%) of the lingual nerves were in contact with the lingual plate at the retromolar and third molar regions. Conclusion: This systematic review mapped out the anatomical location of the lingual nerve in the posterior mandible, highlighting regions that warrant additional caution during surgeries to avoid iatrogenic lingual nerve injuries.

Maxillary Impaction Does Not Negatively Affect the Nasal Airway: A Systematic Review With Meta-Analysis.

PURPOSE: Le Fort I maxillary impaction is an orthognathic surgical procedure to reposition the maxillary complex superiorly. The objective of this study is to investigate if maxillary impaction negatively affects the nasal airway. METHODS: A systematic review with meta-analysis was performed to investigate the effects of maxillary impaction on the nasal cavity. PubMed, Embase, and Cochrane Library databases were accessed. Observational studies, nonrandomized, and randomized controlled trials were included if Le Fort 1 maxillary impaction and nasal airway outcomes assessments were performed. Studies were excluded if maxillary impaction or nasal airway outcome assessment was not performed or if the study included patients with cleft or craniofacial syndromes, previous nasal surgeries, or active respiratory tract. The demographic data, study methodology, magnitude of maxillary impaction, and outcomes related to the nasal airway were collected. These outcomes includes anatomical changes (evaluated by rhinoscopy, acoustic rhinometry, and computed tomography), changes to nasal airflow and resistance (evaluated by rhinomanometry) and changes to quality of life. RESULTS: The search yielded 7517 studies. Ten studies were included after the application of the selection criteria. A total of 126 patients underwent pure maxillary impaction, 97 underwent maxillary impaction and advancement, and 12 had impaction with setback. Despite that maxillary impactions decreased the nasal cavity volume by +21.7%, the cross-sectional area of the narrowest parts of the cavity was only reduced by -8.4%. Maxillary impactions generally increases the nasal airflow (+12.6%) while reducing nasal resistance (-20.2%). Rhinoscopies also showed a reduction in nasal obstruction. CONCLUSION: Maxillary impaction did not negatively affect the nasal airway. The surgeries did not lead to the reduction of the cross-sectional area at the strictures of the nasal cavities. The nasal airflow and resistance was not decreased and increased, respectively. The quality of life of the patients was also not shown to have worsened.

Tooth autotransplantation with 3D-printed replicas as part of interdisciplinary management of children and adolescents: Two case reports.

The management of missing teeth as a result of dental trauma or associated with hypodontia in children and adolescents presents as a clinical challenge for the dental team. One of the options that is regaining popularity is dental autotransplantation. To improve autotransplantation outcomes, careful interdisciplinary planning, surgical simulation using cone beam computed tomography images and three-dimensional-printed teeth replicas should be undertaken for presurgical preparation. This case report showcases two applications of autotransplantation, with emphasis on interdisciplinary management, presurgical preparation and postsurgical orthodontic and aesthetic management to deliver a good long-term, sustainable, biological outcome, as a part of a comprehensive rehabilitation treatment plan in children.

Cross sectional study on the competence and confidence of dental students and graduates in the management of medically compromised patients and acute medical emergencies.

A rapidly aging population means many people have multiple health issues leading to an increased risk of acute medical emergencies. The objective of this study was to evaluate how essential experiential learning is in developing dental graduates' ability to manage medically compromised patients. Three hundred and twenty-seven students and graduates were invited to participate in an online survey to rate their confidence in managing medically compromised patients and acute medical emergencies using a 5-point Likert scale. Competence of knowledge was evaluated using 30 multiple choice questions (MCQs) across six domains. The respondents were also asked whether a theory-only training adequately prepared them to manage medically compromised patients, or whether it must be supplemented with clinical training. Two-hundred and sixty-four responses were collected from 75 undergraduates (UG), 96 junior dental officers (JDO) and 93 senior dental officers (SDO). The UG reported that they infrequently managed medically compromised patients, whereas both the JDO and SDO reported having frequent encounters with these patients. The mean confidence scale in the management of medically compromised patients were 2.62, 3.50 and 3.69 (out of 5), respectively. In contrast, their confidence scale in the management of acute medical emergencies was 2.05, 2.33 and 2.50 (out of 5), respectively. The MCQ scores were 25.51, 26.44 and 26.86 out of 30, respectively. The outcomes of the JDO and SDO were significantly better than the UG (t-tests, p<0.05). All three groups responded that a theory-only training in dental school did not adequately prepare them to manage medically compromised patients. Both the JDO and SDO felt that their clinical work experience better prepared them to manage these patients. Experiential learning from "real-life" clinical experience is an essential component in developing graduates' confidence and competence in the management of medically compromised patients. A dental curriculum with theory-only training in this aspect is inadequate.

Orthognathic Surgery for Obstructive Sleep Apnea.

Obstructive sleep apnea (OSA) involves obstruction or reduction of an individual's airway during sleep and is associated with several comorbidities. Patient evaluation includes detailed history, clinical and radiographic examination, endoscopy, and polysomnography. Management may be nonsurgical or surgical, and Phase II of the Stanford Protocol of surgical management involves maxillomandibular advancement (MMA). Surgical considerations (eg, degree of movement, timing of surgery) and potential complications specific to MMA are discussed in this review. With adequate planning and communication with the patient, MMA is effective in treating OSA, as measured with objective and subjective measures.

Mapping out the surgical anatomy of the lingual nerve:a systematic review and meta-analysis

Objectives@#Understanding the lingual nerve’s precise location is crucial to prevent iatrogenic injury. This systematic review seeks to determine the lingual nerve’s most probable topographical location in the posterior mandible. @*Materials and Methods@#Two electronic databases were searched, identifying studies reporting the lingual nerve’s position in the posterior mandible.Anatomical data in the vertical and horizontal dimensions at the retromolar and molar regions were collected for meta-analyses. @*Results@#Of the 2,700 unique records identified, 18 studies were included in this review. In the vertical plane, 8.8% (95% confidence interval [CI], 1.0%-21.7%) and 6.3% (95% CI, 1.9%-12.5%) of the lingual nerves coursed above the alveolar crest at the retromolar and third molar regions. The mean vertical distance between the nerve and the alveolar crest ranged from 12.10 to 4.32 mm at the first to third molar regions. In the horizontal plane, 19.9% (95% CI, 0.0%-62.7%) and 35.2% (95% CI, 13.0%-61.1%) of the lingual nerves were in contact with the lingual plate at the retromolar and third molar regions. @*Conclusion@#This systematic review mapped out the anatomical location of the lingual nerve in the posterior mandible, highlighting regions that warrant additional caution during surgeries to avoid iatrogenic lingual nerve injuries.

The Provision of Dental Care to COVID-19 Survivors: A Concise Review.

AIMS: It has been reported that there are a certain percentage of COVID-19 patients who recover but suffer from devastating permanent organ damage or failure. Others suffer from long Covid syndrome, with prolonged symptoms that persist more than 12 weeks. However, there is scarcity of literature regarding the provision of dental treatment for these two groups of patients. This manuscript reviews the impact of multi-system involvement on the provision of dental care to these patients. MATERIALS AND METHODS: A search of literature was done in PubMed-Medline and Scopus databases to review the available literature on COVID-19 impacts on pulmonary, cardiovascular, haematologic, renal, gastrointestinal, endocrine, and neurologic systems and respective management in dental clinical settings. RESULTS: The literature search from PubMed-Medline and Scopus databases resulted in 74 salient articles that contributed to the concise review on COVID-19 effects on pulmonary, cardiovascular, haematologic, renal, gastrointestinal, endocrine, and neurologic systems and/or its respective dental management recommendations. CONCLUSIONS: This concise review covers the management of post COVID-19 patients with pulmonary, cardiovascular, haematologic, renal, gastrointestinal, endocrine, or neurologic system complications.

Post Laparoscopy Pain Reduction Project I (POLYPREP I): intraperitoneal normal saline instillation-a randomised controlled trial.

OBJECTIVES: To evaluate the effect of intraperitoneal normal saline instillation (INSI) of 15 mL/kg body weight on postoperative pain after a gynaecological laparoscopic procedure. DESIGN: Randomised controlled trial. SETTING: University Hospital in Kuala Lumpur, Malaysia. PARTICIPANTS: Patients aged 18-55 years, with American Society of Anaesthesiologists (ASA) classification I-II, scheduled for an elective gynaecological laparoscopic procedure for a benign cause. INTERVENTION: The patients were randomly allocated to two groups. In the intervention group, 15 mL/kg body weight of normal saline was instilled intraperitoneally, while the control group received the conventional combination of open laparoscopic trocar valves with gentle abdominal pressure to remove the retained carbon dioxide. MAIN OUTCOME MEASURES: The outcomes measured were the mean pain scores for shoulder and upper abdominal pain at 24 h, 48 h, and 72 h postoperatively. RESULTS: A total of 68 women completed the study, including 34 women in each group. There was no difference in the shoulder pain score at 24 h, 48 h, and 72 h postoperatively. However, a significant improvement in the upper abdominal pain score after 48 h (95% confidence interval [CI] 0.34-1.52, p = 0.019) and 72 h (95% CI 0.19-0.26, p = 0.007) postoperatively were observed. CONCLUSIONS: INSI of 15 mL/kg body weight does not lower postoperative shoulder pain compared to no fluid instillation. A modest pain score improvement was observed in the upper abdominal area at 48 h and 72 h after surgery. An INSI of up to 30 mL/kg body weight may be required to eliminate shoulder pain. Care must be taken before administering a higher amount of INSI, considering the potential risk of peritoneal adhesions. Clinical registration ISRCTN Identifier: 87898051 (Date: 26 June 2019) https://doi.org/10.1186/ISRCTN87898051.

Mechanical properties and in vitro cytocompatibility of dense and porous Ti-6Al-4V ELI manufactured by selective laser melting technology for biomedical applications.

The Ti-6Al-4V alloy is the most common biomaterial used for bone replacements and reconstructions. Despite its advantages, the Ti-6Al-4V has a high stiffness that can cause stress-shielding. In this work, we demonstrated that the selective laser melting (SLM) technology could be used to fabricate porosity in Ti-6Al-4V extra low interstitial (ELI) to reduce its stiffness while improving cell adhesion and proliferation. With a porosity of 14.04%, the elastic modulus of the porous Ti-6Al-4V ELI was reduced to 80 GPa. The compressive stress and the 3-point-bending flexural tests revealed that the porous Ti-6Al-4V ELI possessed a brittle characteristic. The additional pores within the beams of the lattice structures of porous Ti-6Al-4V ELI increased its surface arithmetic average roughness, Ra = 3.94 µm. The in vitro cytocompatibility test showed that the SLM printing process and the post-processes did not cause any toxicity in the MC3T3-E1 cells. The in vitro cell proliferation test also showed that the porous Ti-6Al-4V ELI increased the proliferation rate of osteogenic induced MC3T3-E1 cells on Day 7. The findings from this study would provide engineers and researchers with both the mechanical information and biological understanding of SLM printed porous Ti-6Al-4V ELI, and SLM printed dense Ti-6Al-4V ELI towards biomedical applications.

Dangers with cementation under low-viscosity state: Cement arterio-venogram and bone cement implantation syndrome.

Cement arterio-venogram is a rare event with cement extrusion into femoral nutrient vessels. In literature it is known to be benign with no significant clinical sequelae. It is postulated that it is due to high cement implantation pressure, that results in optimal cement filling quality. All previously reported cases were female patients, and it is thought to be a female only phenomenon due to the relatively narrow femoral canal leading to higher pressures during cementation. In this case series we report 3 cases different to existing literature. All 3 patients showed a cement arterio-venogram together with bone cement implantation syndrome and hypotension intraoperatively. It was also observed that during implantation the cement was of low viscosity. We postulate low cement viscosity during implantation with pressurization is also a contributing factor to these phenomena. This case series also demonstrates the first 2 male cases, showing this the even can occur in males too. The cement arteriovenogram is located at 41%-42% femur length which is within the 'third sixth' of the length of the femur. Good cementation techniques and prevention is also highlighted in this report.

Benefits and Biosafety of Use of 3D-Printing Technology for Titanium Biomedical Implants: A Pilot Study in the Rabbit Model.

BACKGROUND: Titanium has been used in osteosynthesis for decades and its compatibility and safety is unquestioned. Studies have shown that there is release and collection of titanium in the organ systems with little note of toxicity. The gold standard is considered to be titanium osteosynthesis plate produced by milling methods. The use of customized titanium plates produced with 3D printing, specifically direct metal laser sintering, have found increasing use in recent years. It is unknown how much titanium is released in these printed titanium implants, which is known to be potentially porous, depending on the heat settings of the printer. We hypothesize that the amount of titanium released in printed titanium implants may be potentially more or equal compared to the gold standard, which is the implant produced by milling. METHODS: We studied the biosafety of this technology and its products by measuring serum and organ titanium levels after implantation of 3D-printed versus traditionally fabrication titanium plates and screws in a pilot study using the rabbit model. A total of nine rabbits were used, with three each in the control, milled and printed titanium group. The animals were euthanized after six months. Serum and organs of the reticuloendothelial system were harvested, digested and assayed for titanium levels. RESULTS: Organ and serum titanium levels were significantly higher in rabbit subjects implanted with titanium implants (milled and printed) compared to the control group. However, there was no significant difference in organ and serum titanium levels of subjects implanted with milled and traditionally fabricated titanium implants. CONCLUSIONS: The biosafety of use of 3D-printed titanium implants and traditionally fabricated titanium implants are comparable. With this in mind, 3D-printed custom implants can not only replace, but will very possibly surpass traditionally fabricated titanium implants in the mode and extent of use.

Type I, II, and III interferon signatures correspond to COVID-19 disease severity

We analyzed the plasma levels of interferons and cytokines, and the expression of interferon-stimulated genes in peripheral blood mononuclear cells in COVID-19 patients with different disease severity. Mild patients exhibited transient type I interferon responses, while ICU patients had prolonged type I interferon responses with hyper-inflammation mediated by interferon regulatory factor 1. Type II interferon responses were compromised in ICU patients. Type III interferon responses were induced in the early phase of SARS-CoV-2 infection, even in convalescent patients. These results highlight the importance of type I and III interferon responses during the early phase of infection in controlling COVID-19 progression.

Can carotid artery calcifications on dental radiographs predict adverse vascular events? A systematic review.

OBJECTIVES: To investigate the predictive value of carotid artery calcifications (CACs) seen on dental imaging for future adverse events related to cerebrovascular and cardiovascular diseases. METHODS: Electronic databases (PubMed, Embase, SCOPUS and Cochrane) and selected grey literature were searched. Outcomes included stroke, transient ischaemic attack (TIA), myocardial infarction (MI), angina, heart failure, future interventional revascularization procedures and death. Risk of bias was assessed using the Newcastle-Ottawa Scale. RESULTS: 5 studies were selected from 1011 records. All were of moderate to low risk of bias. Results were heterogeneous but showed that patients with CACs on panoramic radiographs (PANs) were more likely to experience strokes, TIA, MI and future revascularization procedures compared to control groups. The differences between groups were not all found to be statistically significant. Bilateral vessel-outlining CACs were an independent risk marker for future vascular events. Patients who are not currently being managed for cardiovascular risk factors should be referred for further evaluation. Those already being treated for atherosclerosis may not benefit from additional investigations. CONCLUSION: The evidence for the predictive value of CACs on PANs for adverse future vascular events is equivocal but can help to identify at-risk patients who require further evaluation. CLINICAL RELEVANCE: Dentists must be able to recognize CACs on PANs and make appropriate referrals for patients to be evaluated for cardiovascular risk factors, especially those who have not previously been assessed.