Mandibular Surgery Research Articles

Modelling the Upper Airways of Mandibular Advancement Surgery: A Systematic Review

Obstructive sleep apnea syndrome is a conceivably hazardous ailment. Most end up with non-reversible surgical techniques, such as the maxillomandibular advancement (MMA) procedure. MMA is an amazingly obtrusive treatment, regularly connected to complexities and facial change. Computational fluid dynamic (CFD) is broadly utilized as an instrument to comprehend the stream system inside the human upper airways (UA) completely. There are logical inconsistencies among the investigations into the utilizations of CFD for OSAS study. Thus, to adequately understand the requirement for OSAS CFD investigation, a systematic literature search was performed. This review features the necessary recommendations to accurately model the UA to fill in as an ideal predictive methodology before mandibular advancement surgery.

Anaesthetic Management of Pyelolithotomy Patient with Restricted Mouth Opening due to Previous Mandibular Surgery- A Case Report

Anaesthetic management of a patient with compromised kidney function, who had restricted mouth opening due to previous surgery for mandibular fracture requiring general anaesthesia, is a challenge for anaesthesiologists. This is a case report of a 45- year-old male patient with renal calculus who underwent left pyelolithotomy surgery under general anaesthesia at our institution. He was admitted with left loin pain of two weeks' duration. Airway control was difficult due to limited mouth opening resulting from mandibular fracture four months prior, for which he underwent open reduction and internal fixation at a different hospital. We anticipated difficulty in securing the airway due to mandibular plate fixation. The airway was secured with orotracheal intubation using a levitan optical stylet under airway block. This case report highlights the importance of optical stylet in the plan B of managing a difficult airway, when a fiberoptic bronchoscope is not available in a critical situation.

Cases of Maxillofacial Trauma Treated at Hospitals in a Large City in Northeastern Brazil: Cross-Sectional Study

Maxillofacial trauma is associated with facial deformation, loss of function, emotional and social impacts, and high financial costs. This study investigated cases of maxillofacial trauma in a large Brazilian city through a cross-sectional study conducted at two public and two private hospitals. Primary data of 400 patients were collected through a questionnaire, clinical examination, and tomography. Statistical analysis at the 5% significance level was performed. Motorcycle accident was the major cause of trauma (41%); the most frequent trauma and treatment were mandibular fracture (24.3%) and surgery (71%), respectively. The female sex was more affected only regarding domestic accidents (p = 0.041) and falls (p < 0.001). Motorcycle accidents were more prevalent among 20 to 29 year-olds (p < 0.001), followed by physical aggression (p < 0.001) and sports accidents (p = 0.004). Falls were more frequent among 40 to 59 year-olds (p < 0.001). Mandibular fracture affected males and 20 to 29 year-olds more and was mainly associated with motorcycle accidents (48.2%) and physical aggression (22.7%) (p = 0.008). Nose fracture was more frequent in falls (29.6%), physical aggression (22.5%), and sports accidents (21.1%) (p < 0.001). Compound fracture was associated with motorcycle accidents (84.2%; p = 0.028). Maxillofacial trauma (mandibular, nasal, and zygomatic fractures) was associated with motorcycle accidents, physical aggression, and falls. Surgical treatment, hospital care, and public services were the most frequent.

Accuracy of mandibular repositioning surgery using new technology: Computer-aided design and manufacturing customized surgical cutting guides and fixation plates

Recent 3-dimensional technology advancements have resulted in new techniques to improve the accuracy of intraoperative transfer. This study aimed to validate the accuracy of computer-aided design and manufacturing (CAD-CAM) customized surgical cutting guides and fixation plates on mandibular repositioning surgery performed in isolation or combined with simultaneous maxillary repositioning surgery. Sixty patients who underwent mandibular advancement surgery by the same surgeon were retrospectively evaluated by 3-dimensional surface-based superimposition. A 3-point coordinate system (x, y, z) was used to identify the linear and angular discrepancies between the planned movements and actual outcomes. Wilcoxon rank sum test was used to compare the outcomes between the mandible-only and the bimaxillary surgery groups with significance at P<0.05. Pearson correlation coefficient compared planned mandible advancement to the outcome from advancement planned. The centroid, which represents the mandible as a single unit, was computed from 3 landmarks, and the discrepancies were evaluated by the root mean square error (RMSE) for clinical significance set at 2 mm for linear discrepancies and 4° for angular discrepancies. There was no statistically significant difference between the planned and actual position of the mandible in either group when considering absolute values of the differences. When considering raw directional data, a statistically significant difference was identified in the y-axis suggesting a tendency for under-advancement of the mandible in the bimaxillary group. The largest translational RMSE for the centroid was 0.77 mm in the sagittal dimension for the bimaxillary surgery group. The largest rotational RMSE for the centroid was 1.25° in the transverse dimension for the bimaxillary surgery group. Our results show that the precision and clinical feasibility of CAD-CAM customized surgical cutting guides and fixation plates on mandibular repositioning surgery is well within clinically acceptable parameters. Mandibular repositioning surgery can be performed predictably and accurately with the aid of CAD-CAM customized surgical cutting guides and fixation plates with or without maxillary surgery.

Efficacy of Fentanyl Transdermal Patch in Impacted Mandibular Third Molar Surgery-A Comparative Study.

Removal of mandibular third molars surgically is one of the most frequently performed oral surgical procedures which are often accompanied with post-operative pain, swelling and trismus. Despite general progress in pain management, moderate to severe acute post-operative pain after removal of lower third molars remains a problem. Fentanyl is an extremely effective drug in the treatment of severe chronic pain such as cancer pain and post-operative pains which acts by increasing patient's tolerance to pain. Fentanyl Transdermal System (FTS) is a rectangular transdermal patch which contains high concentration of fentanyl, a potent short-acting Schedule II opiate. In this study the efficacy of transdermal fentanyl for management of post-operative pain after impacted mandibular 3rd molar surgery is evaluated. 20 patients within the age group of 18-40 years with asymptomatic impacted mandibular third molars were equally divided into 2 groups as group A & group B which underwent surgery in Local Anaesthesia. In every patient one side belonged to group A and other side belonged to group B. 50 μg FTS was applied in group A while placebo patch was applied in group B. Patients in group A performed significantly better than group B in terms of mean pain intensity scores assessed by VAS and VRS along with minimum need of post-operative rescue analgesics. It was found that FTS resulted in significantly better pain relief, longer pain-free intervals, and lesser post-operative analgesic consumption.

Les troisièmes molaires dans la décision thérapeutique en orthodontie

Despite a high prevalence of agenesis, third molars should frequently be considered in our orthodontic treatment plans. The aim of this study was to describe, according to the literature, the therapeutic possibilities of third molar management. The avulsion isn't systematic. The French National Authority for Health has updated its guidance about it. Indeed, surgical procedures can present with potentially irreversible risks (nerve damage, bone necrosis). It is necessary to assess the benefit/risk balance and to inform the patient accordingly. Whether symptomatic or not, pathological third molars are among the most obvious indication for avulsion as well as third molars that may lead to resorption or carious lesion of the adjacent molar. On the other hand, it is not recommended to avulse third molars to prevent the appearance of anterior crowding or in case of a favorable evolution. Some of our orthodontic therapies can lead to the avulsion of the third molars: the orthognathic surgery (especially mandibular surgery) or the distalization. They can be placed by transplantation, by mesialization, sometimes with the help of bone anchors, or by straightening the axis for a prosthetic or implant-prosthetic restoration. In the adolescent, the germs of the third molars would not limit the amount of distalization; these molars would continue to grow despite the distalization of the more anterior molars. Wisdom teeth should be considered as third molars in their own right and can thus be used in edentulous situations.

Evaluation of Nutrient Canals in the Anterior Region of the Mandible in Patients Referring to Radiology Department of Islamic Azad University of Isfahan by Using Cone-Beam Computed Tomography

Introduction: The nutrient canals in the anterior region of the mandible are derived from the incisive branch of the inferior neurovascular bundle the damage of which in any surgery could lead to more hemorrhage and postoperative paresthesia. Evaluating the incidence and anatomical location of these canals using dental CBCT is the purpose of this study.&#x0D; Materials &amp; Methods: In this study, the CBCT scans of 196 patients- consist of 89 women and 107 men with a mean age of 49.1 from the archive of the radiology department of Isfahan Islamic Azad University were scrutinized. Sex, location, number, size (mesial-distal and buccal-lingual diameter), shape (round or ovoid) of nutrient canals were recorded. Results were analyzed using Mann-Whitney, Independent T-test, and Kruskal-Wallis test. (p value &lt; 0.05).&#x0D; Results: There are nutrient canals in 83.6% of the cases, in most of the cases (73.4 %), two nutrient canals in the anterior region of the mandible were detected. The independent t test showed that the average mesial-distal (p value = 0.48) and buccal-lingual (p value = 0.40) nutrient foramen diameter in between dentate and edentulous ones had no meaningful relation. The number of nutrient canals in the anterior region of the mandible in dentate was statistically higher than the edentulous ones (p value &lt; 0.001).&#x0D; Conclusion: There were nutrient canals present in most of the cases. There was no significant correlation between age and the number of nutrient canals in the anterior region of the mandible. There was no significant correlation between sex and the number of nutrient canals in the anterior region of the mandible. There was significant correlation between dentate and edentulous ones and the number of nutrient canals in the anterior region of the mandible. Preoperative knowledge of these findings via CBCT scans would be useful to prevent the complications of mandibular surgery.

Maxillary and Mandibular Healing after Facial Allotransplantation

PURPOSE: Facial transplantation has emerged as a viable option in treating devastating facial injuries. Despite the high healing rate of Le Fort I-II-III and bilateral sagittal split osteotomies (BSSO) in non-transplant patients (with reported non-union rates of 1.6% and 2.6%, respectively),[1,2] previous studies have reported nonunion between the allograft and the recipient’s bone at the area of maxillary and mandibular osteotomies. [3,4] This suboptimal bone healing remains unexplained and is still yet to be investigated. In this study, we present three patients that received facial transplantation at our institution with a focus on the healing of the mandibular and maxillary osteotomies after osteocutaneous face transplantation. METHOD: A retrospective chart review was conducted of facial allotransplantation patients at the Cleveland Clinic from December 2008 to inception. Demographics such as age, date of birth, and sex were recorded. Additional variables included procedures, revisions, reoperations, medications, and bone stability and healing. Computed tomography (CT) images assessed alignment of skeletal components, bony union quality, and stability of fixation. RESULTS: Three patients receiving facial allotransplantation at our institution were included in our study: two had Le Fort III segment transplantation, and one had transplantation of both a Le Fort III segment and mandibular BSSO. The Le Fort III segment in all three patients exhibited mobility and fibrous union at the Le Fort III osteotomy on CT. In contrast, the BSSO healed uneventfully after transplantation and revision surgery, with bony union confirmed by both CT and histology of the fixation area between the donor and recipient mandible bilaterally. No patients with midfacial fibrous union required revision of the nonunion as they were clinically asymptomatic. CONCLUSION: Le Fort osteotomies demonstrated inferior healing in patients undergoing facial transplantation compared to Le Fort osteotomies in patients treated for malocclusion. Interestingly, the mandible healed uneventfully after facial transplantation, likely due to the amount of rich cancellous bone in the mandible. This similarly reflects bone healing rates in patients undergoing mandibular surgery for correction of malocclusion or hand transplantation at the level of the humerus, radius, and ulna. Nonunion of the midface does not require revision unless the patient is clinically symptomatic. REFERENCES: 1. Imholz B, Richter M, Dojcinovic I, and Hugentobler M, Non-union of the maxilla: a rare complication after Le Fort I osteotomy. Revue de stomatologie et de chirurgie maxillo-faciale. 2010; 111(5-6): p. 270-275. 2. Chin M and Toth BA, Le Fort III advancement with gradual distraction using internal devices. Plast Reconstr Surg. 1997; 100(4): p. 819-30; discussion 831-2. 3. Lantieri L, Grimbert P, Ortonne N, et al., Face transplant: long-term follow-up and results of a prospective open study. Lancet. 2016; 388(10052): p. 1398-1407. 4. Goutard M, Lellouch AG, Dussol B, and Lantieri LA, Facial Trauma 8 years after a Face Transplantation. Plast Reconstr Surg Glob Open. 2021; 9(5): p. e3575.

Evaluation of Adjunctive Low Level Laser Therapy in Postoperative Management of Pain, Swelling, Trismus Following Surgical Removal of Impacted Mandibular Third Molars

Our aim is to evaluate the effectiveness of Low Level Laser Therapy (LLLT) in the control of postoperative pain, swelling, and trismus associated with the surgical removal of impacted mandibular third molars. This study was carried out as a single centre, prospective study with a sample size of 30 patients to evaluate the effectiveness of LLLT following surgical removal of impacted third molars. Patients were randomly divided into two groups of 15 each. Group 1(Study /LLLT group) consisted of patients undergoing LLLT and with the use of postoperative analgesics and antibiotics. Group 2 (Control) included patients who were administered postoperative analgesics and antibiotics without the concurrent use of LLLT. The predictor variable was the LLLT application following mandibular third molar impaction surgery. The outcome variables namely pain, swelling, and trismus were evaluated on the day of surgery and 1st, 3rd, and 7th postoperative days (POD).Results:The pain was highest on POD 1 and gradually reduced by POD 7 in the study group when compared to the control group. Swelling showed a steep increase on POD 1 and thereafter a gradual reduction was observed on POD 7, when compared to the control group, the study group showed a significant decrease in swelling. Mouth opening was the lowest on POD1 and gradually increased by POD 7 in the study group than in the control group. Conclusion: The results of the study suggest that the application of LLLT to impacted mandibular third molar sockets helps eliminate/or reduce postoperative pain, swelling, and trismus.

Evaluation of the distribution characteristics of the mandibular lingual foramen and its potential risks during implant surgery using cone-beam computed tomography a cross-sectional, retrospective study.

The lingual foramen is a risk factor for implantation and other mandibular surgeries, but there are few systematic studies on the anatomical and distribution characteristics of the lingual foramen in the entire mandible. A retrospective study was performed using 405 CBCT images. The anatomical characteristics and symmetrical distribution of the mandibular lingual foramen were analyzed. All patients had at least one lingual foramina. According to the positional relationship between the mandibular lingual foramen and the root apex of tooth, the mandibular lingual foramen is divided into the upper lingual foramen and the lower lingual foramen. Upper lingual foramen were divided into three types according to its running direction, namely Type 1 (Enters the mandible and descend in the direction of the lower edge of the mandible), Type 2 (Enters the mandible and descends in the direction of the lower edge of the mandible with branches), and Type 3 (It enters the mandible and divides into two branches, one ascends toward the crest of the alveolar ridge, and the other descends toward the lower edge of the mandible). And their respective prevalence are 84.0% [95% Tolerance Limit (TL) 81.2%-86.8%], 9.9% [95% TL 7.6%-12.1%], and 6.1% [95% TL 4.3%-8.0%]. In addition, the 81.8% [95% TL 79.0%-84.7%] of the upper lingual foramen is distributed in the central incisor area. Lower lingual foramen were divided into three categories according to the running direction, namely Category 1 (Enters the mandible and ascends toward the buccal bone plate), Category 2 (Enters the mandible and descends toward the buccal bone plate), and Category 3 (Go straight into the mandible toward the buccal bone plate). And their respective prevalence are 29.6% [95% TL 26.4%-32.7%], 50.9% [95% TL 47.5%-54.4%] and 19.5% [95% TL 16.8%-22.3%]. The frequency of lower lingual foramen distributed anteriorly to the mental foramen is 55.8% [95% TL 52.3%-59.2%], mid-mental foramen is 21.4%[95% TL 18.5%-24.2%], and posterior to the mental foramen is 22.8% [95% TL 20.0%-25.8%]. Both the upper and lower lingual foramina should be evaluated in the anterior, middle, and posterior regions of the mental foramen before implant surgeries.

Application of 3D-printed Surgical Cutting Guide in Anterior Mandibular Body Ostectomy.

Complications in mandibular surgeries involve nerve and root injuries. Due to the variation of the intraosseous pattern of the inferior alveolar nerve and roots among patients, the risk of injury remains high in complex cases of mandibular body surgeries. This technical note aims to introduce a novel design of surgical cutting guide used in anterior mandibular body ostectomy. Roots of neighboring teeth and the inferior alveolar nerve are segmented and visualized in 3-dimension. Osteotomy planes designed in virtual surgical planning provide an accurate safety distance to the nerve and roots. These planes are translated to a bone-based cutting guide to ensure the osteotomy is conducted as planned. Application of the cutting guide offers protection to the neighboring structures and the simplified structure requires limited preoperative design time of the cutting guide. Therefore, the authors believe this surgical cutting guide would bring accuracy and efficiency to mandibular surgeries.

Design and implementation of a surgical planning system for robotic assisted mandible reconstruction with fibula free flap.

Free fibula flap is the gold standard for the treatment of mandibular defects. However, the existing preoperative planning protocol is cumbersome to execute, costly to learn, and poorly collaborative with the robot-assisted cutting of the fibular osteotomy plane. A surgical planning system for robotic assisted mandibular reconstruction with fibula free flap is proposed in this study. A fibular osteotomy planning algorithm is presented so that the virtual surgical planning of the fibular osteotomy segments can be obtained automatically with selected mandibular anatomical landmarks. The planned osteotomy planes are then converted into the motion path of the robotic arm, and the automatic fibula osteotomy is completed under optical navigation. Surgical planning was performed on 35 patients to verify the feasibility of our system's virtual surgical planning module, with an average time of 13min. Phantom experiments were performed to evaluate the reliability and stability of this system. The average distance and angular deviations of the osteotomy planes are 1.04 ± 0.68mm and 1.56 ±1.10°, respectively. Our system can achieve not only precise and convenient preoperative planning, but also safe and reliable osteotomy trajectory. The clinical applications of our system for mandibular reconstruction surgery are expected soon.

Effect of Dexmedetomidine Added to Lidocaine Cartridge on the Level of Patient Sedation, Cooperation, and Patient and Surgeon Satisfaction during Mandibular Third-Molar Extraction Surgery: A Randomized Double-Blind Controlled Trial.

Background Various methods have been introduced for anxiety control during third-molar extraction surgery. Dexmedetomidine (DEX) is known to have analgesic, anxiolytic, and sympatholytic properties with minimal adverse effects. This study aimed to evaluate the impact of the local injection of the combination of DEX and Lidocaine on patients' anxiety and the surgeon's satisfaction during third-molar extraction surgery. Methods A total number of 26 healthy volunteers with symmetrical bilateral impacted mandibular third-molar teeth indicated for surgical removal were included in this double-blind randomized controlled trial. A single experienced surgeon performed two surgical extraction procedures within at least four-week time intervals using anesthetic cartridges containing “DEX + LIDO” or “LIDO alone” used randomly on each side for each patient. The Visual Analog Scale and the SDFQ index were used to evaluate patients' anxiety and surgeon satisfaction during the procedure. Results SDFQ reports showed that patients in the “DEX” group were 1.5 times more relaxed than those in the “LIDO alone” group. As a result, the level of sedation was considered statistically significant between the two groups (Wilcoxon test, P value <0.019). Wilcoxon test results also showed significant differences between the two groups regarding patients' overall cooperation in terms of interfering movement and verbal presentation of discomfort (P value <0.05); however, this difference was not considered significant regarding nonverbal signs of discomfort (P value >0.05). Moreover, both the surgeon and the patients reported a significantly higher satisfaction rate in the DEX group (paired T-test, df = 25, P value <0.05). Conclusions It was inferred from the outcomes of the present study that the application of DEX added to the LIDO local anesthesia cartridge could significantly benefit anxious patients with previous unpleasant dental treatment experiences. Trial Registration. This trial is registered with the clinical trial registration number: IRCT20200406046966N.

Gingival swelling and diffuse mandibular osteolysis in a 57-year-old woman

A 57-year-old woman was referred from her hematologist for evaluation of a left mandibular gingival swelling of 1 week's duration. The hematologist expressed concern about odontogenic infection owing to the patient’s prolonged immunosuppressive chemotherapy for the management of treatment-resistant multiple myeloma (MM). The diagnosis of MM had been made in 2017, and since then she had received multiple rounds of chemotherapy, undergone autologous stem cell transplantation, and received intravenous zoledronic acid (Zometa; Novartis). Her health history was also significant for type 2 diabetes mellitus, hypertension, and a distant history of mandibular orthognathic surgery. Results of the extraoral examination did not indicate any pathology. The intraoral examination revealed a firm, sessile, nonmobile, 1-cm mass on the buccal gingiva between teeth nos. 21 and 22 (Figure 1). The results of pulpal and periapical testing of adjacent teeth were unremarkable. No evidence of purulent drainage or hemorrhage from the lesion was seen. A cone-beam computed tomographic scan revealed multiple missing teeth in the maxillary and mandibular right quadrants as well as hardware in place from a bilateral sagittal split osteotomy. In addition, multiple ill-defined radiolucencies were notable across the mandible, with cortical perforation apparent in the anterior and left mandible (Figures 2 and 3) without evidence of tooth resorption or displacement. An excisional biopsy was performed of the gingival soft-tissue lesion in the area of teeth nos. 21 and 22 under local anesthesia. The histopathologic examination revealed a gingival soft-tissue lesion composed of an unremarkable superficial squamous mucosa with extensive and diffuse submucosal infiltrates of mature plasma cells (Figure 4). Immunohistochemical staining showed that the plasma cells were positive for cluster of differentiation 138, and in situ hybridization for κ and λ light chains showed that the plasma cells were κ-restricted (Figure 5). 1 O’Connell F.P. Pinkus J.L. Pinkus G.S. CD138 (syndecan-1), a plasma cell marker: immunohistochemical profile in hematopoietic and nonhematopoietic neoplasms. Am J Clin Pathol. 2004; 121: 254-263https://doi.org/10.1309/617DWB5GNFWXHW4L Crossref PubMed Scopus (214) Google Scholar Dr. Barawi is a resident, Department of Oral and Maxillofacial Surgery, University of Illinois at Chicago, Chicago, IL. Mr. Shah is a student, College of Dentistry, University of Illinois at Chicago, Chicago, IL. Dr. Cabay is an associate professor of clinical pathology, Department of Pathology, College of Medicine; a clinical associate professor, Department of Otolaryngology, College of Medicine; and an associate professor, Department of Oral Medicine and Diagnostic Sciences, College of Dentistry, University of Illinois Hospital, University of Illinois at Chicago, Chicago, IL. Dr. Callahan is an assistant professor, Department of Oral and Maxillofacial Surgery, University of Illinois at Chicago, Chicago, IL.

A Comparison between the Outcomes of Wound Closure by Primary and Secondary Healing after Mandibular 3rd Molar Impaction Surgery

Background: The one of the most frequently performed procedure by the surgeon in the oral and maxillofacial surgeries is removal of mandibular third molar. Objective: The study aimed to compare the process of primary and secondary wound closure outcomes after the surgical removal of impacted mandibular third molar. Study design: It is a comparative study conducted at Armed Forces Institute of Dentistry, Rawalpindi for the duration of six months from Jan 2022 to June 2022. Material and Methods: The 65 patients visited the oral and maxillofacial surgery department of hospital were included in the study. According to the inclusion criteria, these patients had impacted their third molar and they were medically fit and ready to come for follow ups after the operation as well. The patients were divided into two groups. The group A had 33 patients, the average age of these patients was 30 years and proportion of male and female among these 33 patients was 40% male (13) and 60% female (20). Group B had 32 patients and among those 32 patients there were 46% male (14) and 53% female (18) and the average age of the participants was 27. Results: The percentage incidence of swelling and pain was higher in the group A. The values was statistically significant. The mouth opening was highly observed in the group B patients. The post-operative pain was measured at first day, third day and 7th day by making use of the visual analog scale. The comparison was made. The mean pain score on third day was 4.9 and 3.5 and on the seventh day the mean pain score was 3.2 and 1.5 respectively for group A and B. the overall variation in pain scores were significantly high. Conclusion: In this study, the conclusion is made that the secondary closure was a suitable option then the primary closure for the post-operative pain and swelling. There was no variation found in case of periodontal healing irrespective of the closure procedure used, but the risk of infection and food impaction is more in case of secondary closure. Therefore, if patients have poor hygiene conditions secondary closure is not suitable for them. Keywords: wound closure, healing type and mandibular third molar.

Main clinical approaches to orthognathic surgery for class II open bite and genioplasty patients: a brief systematic review

Introduction: Orthognathic surgery (OS) is used to improve the patient's facial appearance and to correct maxillary and mandibular deformities resulting from malocclusions, disease, or trauma. In this context, genioplasty is a procedure to correct an aesthetic and functional deformity of the chin region, improving the contour. Moreover, anterior open bite (AOB) is the lack of vertical contact or negative overbite between the anterior teeth of the superior and inferior arches when the posterior teeth are in occlusion. Objective: The present study aimed to perform a brief systematic review with risk of bias analysis by funnel plot to highlight the main clinical approaches of orthognathic surgery in class II patients with open bites and also concerning genioplasty. Methods: The research was carried out from February 2022 to May 2022 and developed based on Scopus, PubMed, Science Direct, Scielo, and Google Scholar. The quality of the studies was based on the GRADE instrument and the risk of bias was analyzed according to the Cochrane instrument. Results and Conclusion: A total of 115 articles were found. In total, 57 articles were fully evaluated and 34 were included and evaluated in this study. And of the total of 34 articles, only 11 articles were developed as the main clinical results. A total of 32 articles were excluded because they did not meet the GRADE classification, and 16 were excluded because they were at risk of bias. The symmetric funnel plot does not suggest a risk of bias between the small sample size studies. A retrospective observational study compared 57 patient charts on treatment outcomes for anterior occlusion and vertical skeletal stability after maxillary or mandibular surgery to correct Class II malocclusion with a mild to moderate open bite. After surgery, 87% of Le Fort I patients and 63% of patients with bilateral sagittal split osteotomy had a positive overbite, and at the 6-month follow-up, the percentages were 90% and 74%, respectively. Another study showed Class II patients had significantly greater amounts of lateral and lower translation than class III patients. Also, genioplasty represents one of the most common auxiliary procedures and may be associated with corrective surgery for dentofacial dysmorphisms. However, care must be taken with mental nerve injuries, asymmetries, and intraoperative bleeding are the main immediate complications.

Anti-Bedsore Heel Disc for Nasotracheal Tube Stabilization during Mandibular Asymmetry Surgery and Stable Bone Osteosynthesis—Surgeon and Anesthesiologist Surgical Comfort

Nowadays, maxillo-facial surgery procedures are greatly dependent on good general anesthesia and adequate maintenance care of the airways. Nasotracheal intubation (NTI) is one of the most common ones, especially in orthognathic surgery, temporomandibular joint-related surgeries, or others. Nasotracheal intubation itself is not a problem; however, maintaining its stable and safe position, regardless of the excess of surgical maneuvers in the facial skeleton, is important. There are a lot of techniques, personal modifications, and materials used to support tube placement. It is quite common that either plaster or a bandage roll can be useful with a combination of various forms of sponges or wipes in different shapes, sizes, and elasticity to support the tube’s adequate position, especially when maintaining a good shape and position of the nose and symmetry line and avoiding unnecessary tube flexion. In the following paper, one of the tube support alternatives with an anti-bedsore heel disc will be presented.

What Is the Accuracy of Bimaxillary Orthognathic Surgery Using Occlusally-Based Guides and Patient-Specific Fixation in Both Jaws? A Cohort Study and Discussion of Surgical Techniques

The development of advanced digital orthognathic surgical protocols requires investigation to determine the accuracy of surgical outcomes. This report's purpose is to quantify 3-dimensional linear discrepancies between simulated and actual results for double-jaw orthognathic surgery utilizing occlusally-based guides in conjunction with patient-specific fixation in both jaws. This retrospective cohort study assessed the accuracy of double-jaw orthognathic surgery, in all cases performed by 1 surgeon between May 2019 and January 2021, utilizing occlusally-based guides and patient-specific fixation plates in both maxillary and mandibular surgeries. The primary outcome was absolute linear discrepancy between virtually-planned and surgically-achieved maxillary and mandibular position in 3 dimensions. Secondary outcomes were relative (directional) discrepancy, to assess if protocols erred in 1 direction of each surgical axis. Sequencing of bimaxillary surgery, age, and sex were covariates. Absolute and relative linear differences at A-point, B-point, and pogonion were evaluated using t tests. Descriptive statistics were amassed, and results were analyzed to determine if discrepancies differed from a null hypothesis of 2-mm error. Forty-nine patients were enrolled, consisting of 25 males and 24 females with a mean age of 24.8years. Thirty-five single-piece and 14 multipiece LeFort I osteotomies, 49 bilateral sagittal splits, and 35 genioplasties were studied; there were 22 maxilla-first and 27 mandible-first surgeries. Mean A-point absolute discrepancies of 0.57 (95% confidence interval: 0.41-0.73), 0.37 (0.24-0.50), and 0.45 (0.33-0.57) mm were observed in horizontal, transverse, and vertical planes, respectively. B-point discrepancies were 1.15 (0.79-1.52), 0.62 (0.47-0.78), and 1.14 (0.91-1.38) mm. Pogonion discrepancies were 1.29 (0.86-1.73), 0.85 (0.64-1.06), and 1.24 (1.00-1.49) mm. All P values were <.001. Sequencing of bimaxillary surgery did not alter absolute differences (P=.2 to>.9) with A-point discrepancies consistently smaller than B-point and pogonion discrepancies regardless of sequencing. Mandible-first surgery was associated with posterior directional error; both sequences were associated with superior directional error at B-point and pogonion. Bimaxillary orthognathic surgery utilizing a patient-specific protocol in both jaws produces results highly reproducible to planned simulated surgery and accurate below a 2-mm hypothesis, with maxillary discrepancies approaching 0.5mm and mandibular discrepancies approaching 1mm.

Two-Axis Continuous Distractor for Mandibular Reconstruction.

The application of Distraction Osteogenesis (DO) techniques in the reconstruction of skeletal deficiencies is a relatively new topic in the fields of oral and maxillofacial surgeries. In many reconstruction applications, using DO is the preferred technique, as opposed to conventional reconstruction techniques, as there are more advantages and fewer side effects when it is used. The first generation of DO devices is made up of manual distractors that can apply an intermittent distraction force to the bone segment during the distraction process. Manual DO techniques have shown the functionality of the DO technique. Further research has recently been performed on the development of automatic devices for generating a controlled continuous force. However, the existing automatic techniques have limitations, and are yet to be used in reconstruction applications in humans. There is still a gap between the developed techniques and an ideal distractor to be used in mandibular reconstruction surgeries. In this research, a two-axis continuous distractor is proposed for use in mandibular reconstruction applications. The proposed distractor can generate two continuous distraction forces that can be applied to two independent distraction vectors. The proposed device can perform the standard distraction process using the predetermined distraction factors. The control system has a high positioning accuracy and resolution in controlling the position of the intra-oral end effectors while applying two continuous forces for moving the bone segment. The proposed two-axis continuous distractor meets the current requirements, and can be used as an ideal continuous DO device for different mandibular reconstruction applications.

Mandibular Reconstruction Using Iliac Flap Based on Occlusion-Driven Workflow Transferred by Digital Surgical Guides

The current standard for mandibular reconstruction is a contour-based approach using a fibular flap offering good cosmetic results but challenging to reconstruct using dental implants. An iliac flap is more amenable to implant placement and better suited for occlusion-driven reconstruction. We aimed to describe an occlusion-driven workflow that involves the use of digital surgical guides to perform mandibular reconstruction using an iliac flap; we also aimed to compare our results to those we achieved with conventional contour-based reconstruction. This was a retrospective cohort study. All patients who underwent mandibular reconstruction with an iliac flap at our university hospital between September 2017 and December 2019 were considered eligible for the study. The inclusion criteria included mandibular defects after tumor ablation and stable preoperative occlusal relationship. The exclusion criteria were as follows: defects involving the condyle and ramus, temporomandibular joint disease, and obvious preoperative nontumor-related facial asymmetry. To evaluate surgical outcomes, patients were assigned to 2 groups based on the implemented surgical workflow: the occlusion-driven and traditional contour-driven groups. The intermaxillary distance, intermaxillary angle, surface deviation, and implantation rates were compared between the 2 groups. The operating time, length, and number of iliac bone segments were recorded. Intergroup differences were investigated using an independent samples t test and Fisher exact test. Overall, 24 patients were included (13 in the occlusion-driven group and 11 in the contour-driven group). Implantation rate was higher in the occlusion-driven group (61.5%) compared with the contour-driven group (18.2%; P=.047). The average acceptable intermaxillary distance was greater in the occlusion-driven group (92.3±27.7%) than in the contour-driven group (47.0±47.6%; P=.01). The average intermaxillary angle was 88.2±8.4° in the occlusion-driven group and 76.4±10.3° in the contour-driven group (P<.01). Digital surgical guides can precisely transfer virtual surgical planning to real-world mandibular surgery. An occlusion-driven workflow might provide a better intermaxillary jaw relationship than traditional contour-driven surgical procedures, resulting in improved mastication.