Effects of RNA m6A writer METTL3 and hDPSCs on the peripheral nerve regeneration: In vitro and in vivo study.

PURPOSE: This study aimed to investigate whether RNA m6A participated in the differentiation and proliferation of dental pulp stem cells and improved peripheral nerve regeneration using a rat model of crushed mental nerve injury. MATERIALS AND METHODS: The components of RNA m6A were analyzed through qRT-PCR, while cell proliferation of different groups, including over-expression METTL3 (OE-METTL3) hDPSCs group, knock-down METTL3 (KD-METTL3) hDPSCs group and hDPSCs group in vitro, was clarified by MTT assay. Five groups were designed, namely, Control group, Sham group, hDPSCs group, OE-METTL3 group and KD-METTL3 group. After crushed right mental nerve injury, cells of different groups were transplanted into the lesion area (6 ul in volume). At one, two and three weeks later, histomorphometric analysis and sensory test were conducted in vivo. RESULTS: qRT-PCR results showed that "METTL3" was participated in the differentiation of dental pulp stem cells. There were differences (P < 0.05) between OE-METTL3 group and control group in MTT results in the third, fourth and sixth days. Moreover, the sensory test revealed significant differences (P < 0.05) in difference score and gap score between OE-METTL3 group and KD-METTL3 group in the first and third weeks. The axon counts and retrograde labeled neurons significantly increased in OE-METTL3 group compared with KD-METTL3 group. CONCLUSIONS: These results demonstrated that RNA m6A participated in the differentiation and proliferation of dental pulp stem cells, and that OE-METTL3 group exhibited the greater ability to improve peripheral nerve regeneration than KD-METTL3 group and hDPSCs group.

Transoral endoscopic thyroidectomy vestibular approach as a novel technique for pediatric populations: Results from a single surgeon.

Background: The transoral endoscopic thyroidectomy vestibular approach (TOETVA) is increasingly being adopted worldwide because of its many advantages. However, there are few reports on the effectiveness and safety of TOETVA in children. In this study, we report the results of the application of TOETVA on 27 pediatric patients in Vietnam. To the best of our knowledge, this is also the largest sample size of the TOETVA technique performed by a single surgeon on pediatric patients worldwide. Patients and methods: From June 2020 to February 2022, we performed TOETVA on 27 pediatric patients (≤ 18 years old). The outcomes of the procedure were retrospectively reviewed. Results: Our study was conducted on 27 pediatric patients, of whom 24 were female (88.9%). The mean age was 16.3 ± 2 (range 10-18). Fifteen patients had benign thyroid nodules with a mean nodule size of 31.6 ± 7.1 (range 20-50mm), and 12 patients had papillary thyroid carcinoma with a mean nodule size of 10.2 ± 5.6 (range 4-19mm). All 27 patients underwent successful TOETVA without any conversion to open surgery. The 15 patients with benign thyroid nodules had lobectomies with a mean operative time of 83.3 ± 10.5 (range 60-105 minutes). Among the 12 patients diagnosed with thyroid cancer, ten had a lobectomy, isthmusectomy, and central neck dissection, with a mean operative time of 89.8 ± 5.7 (range 80-100 minutes). The other two underwent total thyroidectomy with central lymph node dissection with a mean operative time of 132.5 minutes. The mean hospital stay was 4.7 ± 0.9 (range 3-7 days). No patient had permanent complications, such as hypocalcemia, recurrent laryngeal nerve injury, or mental nerve injury. The rates of temporary recurrent laryngeal nerve injury and mental nerve injury were 3.7% and 11.1% respectively. Conclusions: TOETVA may be a feasible and safe surgical method for children with thyroid disease. However, we recommend that only high-volume thyroid surgeons with experience in TOETVA should perform TOETVA on the pediatric population.

Parestesia do nervo alveolar inferior decorrente de procedimentos cirúrgicos e suas formas de tratamentos / Paresthesi of the lower alveolar nerve resulting from surgical procedures and its forms of treatment

Nas cirurgias odontológicas é possível que ocorra alguns acidentes ou complicações que podem interferir no dia a dia do paciente. A lesão do nervo alveolar inferior é uma complicação decorrente de cirurgias orais que podem causar um distúrbio de sensibilidade transitória ou persistente, na região do lábio inferior e na região delimitada do forame mentoniano e hemi-arco da mucosa. O diagnóstico da parestesia pode ser feito através de testes mecanoceptivos e nocioceptivos em que o profissional escolherá para qual melhor se adapte no paciente. O objetivo do presente trabalho foi abordar por meio de uma revisão de literatura as formas de diagnóstico e tratamento da parestesia do nervo alveolar inferior decorrentes de cirurgias orais. As bases de dados utilizadas para confecção desta revisão são encontradas nas bibliotecas virtuais eletrônicas: BVS (Biblioteca Virtual em Saúde), LILACS (Literatura Latino-Americana e do Caribe em Ciências da Saúde) e Pubmed. Como critério de inclusão foram selecionados artigos publicados de 2012 a 2022 em língua inglesa, portuguesa e espanhola. Após a leitura do título e resumo dos resultados da pesquisa e aplicação dos critérios de inclusão e exclusão dentre eles foram excluídos 883, pois não se enquadravam no nosso critério de inclusão. No final, foram selecionados 13 estudos por meio de base de dados, que serviram de base para esta revisão. Concluímos que as formas de tratamento para a parestesia na literatura, são um pouco escassas e conflitantes, mas relata que o uso da laserterapia e acupuntura tem sido uma forma de tratamento com um bom índice de sucesso, e para os casos que não sejam suficientes tais tratamentos, pode-se optar por uma cirurgia(AU)

In dental surgeries it is possible to have some accidents or complications that can interfere with the patient's day. Injury to the inferior alveolar nerve is a complication resulting from oral surgeries that can cause a disturbance of sensitivity that can be transient or persistent in the region of the lower lip and in the delimited region of the mental foramen and hemiarch of the mucosa. The diagnosis of paresthesia can be made through mechanoceptive and nocioceptive tests that the professional will choose, which best suits the patient. The objective of the present work is to approach, through a literature review, the forms of diagnosis and treatment aimed at inferior alveolar nerve paresthesia resulting from oral surgeries. The databases used for this review are found in the virtual electronic libraries: VHL (Virtual Health Library), LILACS (Latin American and Caribbean Literature on Health Sciences) and Pubmed. As inclusion criteria, articles published from 2012 to 2022 in English, Portuguese and Spanish were selected. After reading the title and summary of the research results and applying the inclusion and exclusion criteria, 883 were excluded, as they did not meet our inclusion criteria. In the end, 13 studies were selected from the database, which served as the basis for this review. We conclude that the forms of treatment for paresthesia in the literature are a little scarce and conflicting, but it reports that the use of laser therapy and acupuncture has been a form of treatment with a good success rate, and for cases that are not enough, such treatments, one can opt for surgery(AU)

The ambulatory transoral endoscopic thyroidectomy vestibular approach is safe and economical for patients with thyroid nodules.

Background: Ambulatory thyroid surgery has been increasingly performed in recent years. However, the feasibility of the ambulatory transoral endoscopic thyroidectomy vestibular approach (TOETVA) has not been evaluated. We aimed to evaluate the safety, economy, and mental health outcomes of ambulatory TOETVA. Methods: We retrospectively reviewed the data of patients who underwent TOETVA between March 2019 and August 2022. The procedure was performed by a skilled surgical team from the Department of Thyroid Surgery of the affiliated Yantai Yuhuangding Hospital of Qingdao University. Patients were enrolled in the ambulatory (n=166) and conventional (n=290) groups, based on their chosen procedure. We analyzed patients' clinical characteristics, surgical outcomes, Hamilton Anxiety Rating Scale (HAM-A) scores, and hospitalization costs. Results: Of 456 patients, 166 underwent ambulatory TOETVA and 290 underwent conventional TOETVA. No significant differences were found in clinical and surgical characteristics between the groups, including sex (P=0.363), age (P=0.077), body mass index (P=0.351), presence of internal diseases (P=0.613), presence of Hashimoto's thyroiditis (P=0.429), pathology (P=0.362), maximum tumor diameter (P=0.520), scope of surgery (P=0.850), or operative time (P=0.351). There were no significant differences in maximum tumor diameter (P=0.349), extrathyroidal tissue invasion (P=0.516), number of retrieved central lymph nodes (P=0.069), or metastatic central lymph nodes (P=0.897) between the groups. No significant differences were found in complications, including transient hypoparathyroidism (P=0.438), transient vocal cord palsy (P=0.876), transient mental nerve injury (P=0.749), permanent mental nerve injury (P=0.926), and other complications (P=1.000). Ambulatory patients had shorter hospital stays (P<0.001) and reduced hospitalization costs (P<0.001). There was no significant difference in HAM-A scores between the groups (P=0.056). Conclusions: Ambulatory TOETVA is a safe, feasible, and cost-effective procedure for selected patients. This procedure resulted in shorter hospital stays, decreased medical costs, and did not increase patient anxiety. To ensure patient safety, surgical teams must inform patients of the indications, when to seek help, and how to receive the fastest medical attention.

Assessment of Panoramic Radiographic Variables as Predictors of Inferior Alveolar Nerve Injury During Third Molar Extraction

ABSTRACT Objective: To assess the role of radiological predictive markers on orthopantomogram for inferior alveolar nerve (IAN) injury related to the removal of mandibular third molar surgery and the occurrence of post-operative IAN paresthesia. Material and Methods: This prospective observational study was conducted on 60 patients (aged 17-35 years) indicated for extraction and showed one or more of the seven previously known panoramic radiographic risk signs of IAN injury. Variables such as age, sex, tooth angulation, and relationship with the inferior alveolar canal (IAC) were assessed to see their outcome on IAN injury. Data analysis is presented through tables and descriptive methods. Results: Among patients, 26 were male and 34 were female, with a mean age of 26.17 years. Out of seven radiological predictive markers, only six were found in this study, whereas one marker, viz. interruption of white line of the canal was not found. After surgical removal of the lower third molar, only two patients with radiographic signs showing the deflection of roots and darkening of roots continued with sensory deficit 5 weeks post-operatively. Conclusion: The risk of inferior alveolar nerve injury during lower third molar surgery is very low, even in patients with radiological predictive markers.

Risco de lesão do ramo mandibular do nervo trigêmeo na fratura de mandíbula: um estudo anatômico / Risk of injury to the mandibular branch of the trigemal nerve in jaw fracture: an anatomical study

O nervo mandibular V3 é a terceira divisão do nervo trigêmeo, apresenta fibras motoras e sensitivas, sendo a ramificação mista deste nervo. Seus ramos eferentes são responsáveis pela motricidade dos músculos mastigatórios, inerva os músculos milo-hióideo, ventre anterior do digástrico, tensor do véu palatino e tensor do tímpano. Suas fibras aferentes são responsáveis pela sensibilidade da região inferior da face e cavidade oral, dentes inferiores, parte da língua e propriocepção da cápsula da articulação temporomandibular ATM. O objetivo deste estudo é explanar as possíveis lesões no nervo mandibular, suas ramificações e estruturas adjacentes no caso de fraturas na mandíbula, colaborando com informações detalhadas para posterior estudo de acadêmicos e cirurgiões dentistas. Foi realizada uma pesquisa de campo, exploratória e descritiva, com abordagem quanti-qualitativa, para descrição e análise do trajeto do V3 até a sua chegada no osso mandibular, assim como de estruturas que compõem a topografia adjacente a mesma utilizando uma hemiface intacta de um cadáver do sexo masculino no Laboratório de Anatomia Humana das Faculdades Nova Esperança, na cidade de João Pessoa. Devido à proximidade do nervo mandibular com o processo coronoide, fraturas nesta parte do osso mandíbula, podem ocasionar lesões no V3, além de traumas no osso temporal, e consequentemente de todo o gânglio trigeminal. Além destas, estruturas adjacentes como a glândula parótida, artérias maxilar e facial, ATM, e os nervos alveolar inferior, mentual e lingual, podem ser lesionadas em uma fratura mandibular. As lesões nestes nervos, podem resultar em redução grave da qualidade de vida e dor crônica, gerando desconfortos para o paciente. Diante do exposto fica evidente a importância de conhecer a anatomia topográfica da mandíbula e suas estruturas vasculonervosas, seu trajeto e a localização. Houve dificuldade na discussão devido à escassez da literatura em relação à temática proposta. Dessa forma, é necessário motivar novos estudos sobre a temática a fim de ampliar o conhecimento dos profissionais de saúde e estimular novas técnicas para diagnóstico precoce e melhorar os resultados terapêuticos, impactando positivamente na sobrevida de pacientes com fraturas de mandibulares(AU)

The mandibular nerve V3 is the third division of the trigeminal nerve, has motor and sensory fibers, being the mixed branch of this nerve. Its efferent branches are responsible for the motricity of the masticatory muscles, innervating the mylohyoid muscles, anterior belly of the digastric, soft palate tensor and tympanic tensor. Its afferent fibers are responsible for the sensitivity of the lower face and oral cavity, lower teeth, part of the tongue and proprioception of the capsule of the temporomandibular joint TMJ. The aim of this study is to explain the possible injuries to the mandibular nerve, its ramifications and adjacent structures in the case of mandible fractures, collaborating with detailed information for further study by academics and dentists. A field research, exploratory and descriptive, with a quantitative-qualitative approach, was carried out to describe and analyze the path of the V3 until its arrival in the mandibular bone, as well as structures that make up the topography adjacent to it using na intact hemiface of a male cadaver at the Human Anatomy Laboratory of Faculdades Nova Esperança, in João Pessoa city. Due to the proximity of the mandibular nerve with the coronoid process, fractures in this part of the mandible bone can cause injuries to the V3, in addition to trauma to the temporal bone, and consequently to the entire trigeminal ganglion. In addition to these, adjacent structures such as the parotid gland, maxillary and facial arteries, TMJ, and the inferior alveolar, mental and lingual nerves can be injured in a mandibular fracture. Damage to these nerves can result in severely reduced quality of life and chronic pain, causing discomfort for the patient. Given the above, the importance of knowing the topographic anatomy of the mandible and its vascular-nervous structures, its path and location is evident. There was difficulty in the discussion due to the scarcity of literature regarding the proposed theme. Thus, it is necessary to motivate further studies on the subject in order to expand the knowledge of health professionals and encourage new techniques for early diagnosis and improve therapeutic results, positively impacting the survival of patients with mandibular fractures(AU)

Effect of No-ozone Cold Plasma on Regeneration after Crushed Mental Nerve Injury in rats.

Background: This experimental research aimed to determine whether No-ozone Cold Plasma (NCP) has regenerative effect on crushed injured sensory nerves in a rat model (Wistar A) and to evaluate whether NCP can be used as an alternative treatment method for sensory nerve injury in the oral-maxillofacial region. Methods: A total of 10 Wistar A rats were used for this experiment. They were divided into three groups according to whether the mental nerve of the left mandible was injured and NCP was applied or not: group 1 (n=3) (non-mental nerve damage, non-MD) - the left mental nerve was exposed and non-damaged; group 2 (n=3) (mental nerve damage, MD) - the left mental nerve was exposed and damaged, NCP was not applied; and group 3 (n=4) (mental nerve damage and NCP, MD-NCP) - the left mental nerve was exposed and damaged, NCP was applied with regular intervals (three times a week). Results: For the behavior analysis, von Frey test was used. Furthermore, the nerve tissues were examined with hematoxylin and eosin (H&E) staining, and the extent of neurorecovery was evaluated with the immunofluorescence staining of certain markers. The behavioral analysis showed that the function recovery sensory nerve was faster in group 3 (MD-NCP). In the histomorphologic and immunofluorescence analyses, the expression of the factors involved in neurorecovery was much higher in group 3 than in group 2 (MD). Conclusions: The expeditious recovery of sensory nerve function as well as the higher expression of the factors indicating nerve function recovery in the NCP-treated group suggest that NCP has a positive effect on regeneration after sensory nerve crushing injury. Therefore, in the case of sensory impairment of the oral-maxillofacial region, no-ozone cold plasma can be applied for therapeutic effect.

Clinical application of transoral and submental thyroidectomy (TOaST): a series of 54 human cases.

OBJECTIVE: A new endoscopic thyroidectomy approach-transoral and submental endoscopic thyroidectomy (TOaST)-was applied in clinical practice and considered an improved approach for endoscopic thyroid surgery via the oral approach. This paper discusses the feasibility and effectiveness of this surgical method. METHODS: A retrospective analysis was performed on the clinical data of 54 patients who had undergone TOaST in the thyroid disease center of the First Affiliated Hospital of Nanchang University between December 2020 and December 2021. The surgical data and techniques, complications, and cosmetic outcomes of these patients were studied. RESULTS: Among the total 54 patients, 23 underwent unilateral subtotal thyroidectomy, 3 patients underwent bilateral subtotal thyroidectomy, 27 with unilateral thyroid cancer underwent affected thyroid + isthmus + central lymph node resection, and only 1 patient underwent total thyroidectomy. The mean operative time was 88.06 ± 12.03 min (range: 65-135 min), the mean intraoperative blood loss was 8.61 ± 4.60 ml (range: 5-20 ml), the mean postoperative drainage volume was 49.96 ± 9.88 ml (range: 30-60 ml), the mean drainage time was 36.61 ± 2.65 h (range: 32-50 h), and the mean length of hospital stay was 46.63 ± 3.28 h (range 45-70 h). One patient experienced transient recurrent laryngeal nerve injury, and another patient experienced transient parathyroid dysfunction; there was no superior laryngeal nerve injury and other complications, such as postoperative subcutaneous hematoma, hypercapnia, mental nerve injury, tracheoesophageal injury, infection, or lymphatic leakage. CONCLUSION: TOaST cannot only achieve a good therapeutic effect but also avoid mental nerve injury, reduce the discomfort of the patient's jaw, obtain a good cosmetic effect, and facilitate the operation of the operator. It is an endoscopic thyroidectomy technique with a certain clinical value.

Artificial intelligence in positioning between mandibular third molar and inferior alveolar nerve on panoramic radiography.

Determining the exact positional relationship between mandibular third molar (M3) and inferior alveolar nerve (IAN) is important for surgical extractions. Panoramic radiography is the most common dental imaging test. The purposes of this study were to develop an artificial intelligence (AI) model to determine two positional relationships (true contact and bucco-lingual position) between M3 and IAN when they were overlapped in panoramic radiographs and compare its performance with that of oral and maxillofacial surgery (OMFS) specialists. A total of 571 panoramic images of M3 from 394 patients was used for this study. Among the images, 202 were classified as true contact, 246 as intimate, 61 as IAN buccal position, and 62 as IAN lingual position. A deep convolutional neural network model with ResNet-50 architecture was trained for each task. We randomly split the dataset into 75% for training and validation and 25% for testing. Model performance was superior in bucco-lingual position determination (accuracy 0.76, precision 0.83, recall 0.67, and F1 score 0.73) to true contact position determination (accuracy 0.63, precision 0.62, recall 0.63, and F1 score 0.61). AI exhibited much higher accuracy in both position determinations compared to OMFS specialists. In determining true contact position, OMFS specialists demonstrated an accuracy of 52.68% to 69.64%, while the AI showed an accuracy of 72.32%. In determining bucco-lingual position, OMFS specialists showed an accuracy of 32.26% to 48.39%, and the AI showed an accuracy of 80.65%. Moreover, Cohen's kappa exhibited a substantial level of agreement for the AI (0.61) and poor agreements for OMFS specialists in bucco-lingual position determination. Determining the position relationship between M3 and IAN is possible using AI, especially in bucco-lingual positioning. The model could be used to support clinicians in the decision-making process for M3 treatment.

The Assessment of Neurosensory Disturbance Following Bilateral Sagittal Split Osteotomy With Subjective and Three-Dimensional Evaluation.

PURPOSE: Inferior alveolar neurosensory disturbance (IAND) is the most common complication of bilateral sagittal split osteotomy (BSSO). The aim of the present study was to evaluate IAND with subjective tests postoperatively and assess the relationship between three-dimensional measurements of the mandibular canal (MC) and IAND. METHODS: Eighteen patients (Mean age: 24.05 ±â€Š5.85 years) treated with BSSO were retrieved from the archive. Subjective tests (light touch, tactile sensitivity, 2-point discrimination, brush-stroke directional discrimination, sharp/blunt discrimination, dental vitality, questionnaire) and three-dimensional measurements related to MC and fixation screws were done postoperatively (on average 20.43 ±â€Š8.76 months after surgery). Statistical significance was set at P  < 0.05. RESULTS: Subjective test results were found compatible with each other except brush-stroke directional discrimination test. According to the questionnaire, IAND was apparent in all patients immediately after surgery, and recovery after 1 to 2 years was statistically significant ( P  < 0.05). Preoperative ramus width, medial and lateral cancellous bone lengths, the decrease in MC length, and the presence of screw in MC were not related to IAND ( P  < 0.05). CONCLUSIONS: There is a high incidence of IAND following BSSO, and the subjective tests are efficient to evaluate the disturbance. Spontaneous recovery of the nerve occurs during the follow-up periods. Instead of preoperative measurements of bone thickness, MC length, and the position of fixation screws, the surgical procedure seems to be more important in IAND occurrence.

Vestibular landmarks to minimize injury to the mental nerve during transoral endoscopic thyroidectomy-vestibular approach (TOETVA) procedure: an anatomical study / Puntos de referencia vestibulares para minimizar la lesión del nervio mentoniano durante el procemiento de abordaje vestibular de tiroidectomía endoscópica transoral (TOETVA): un estudio anatómico

SUMMARY: The aim of this study is to reveal the morphometry of the mental nerve to describe a safe zone for minimizing mental nerve damage during transoral endoscopic thyroidectomy-vestibular approach (TOETVA). This study was performed on 12 cadavers. Localization of mental foramen according to teeth, distances of buccogingival sulcus-lip (BG-L), mental foramen-midline (MF-Midline), mental foramen - buccogingival sulcus (MF - BG), commissure - branching point (Cm - Br), branching point - vertical projection of branching point on lower lip (Br - LVP), vertical projection of branching point on lower lip - commissure (LVP - Cm), commissure - midline (Cm - midline), angles of mental (AM), angular (AA) and labial branches (AL) and branching patterns were recorded. Type 1 was mostly found as branching pattern in this study (45.8 %). A new branching pattern (type 9) was found on one cadaver. Mental foramen was mostly located at level of second premolar teeth. According to morphometric results of this study; supero- lateral to course of angular branch and infero-medial to course of mental branch of mental nerve on lower lip after exiting the mental foramen were described as safe zones during surgery for preserving mental nerve and its branches.

RESUMEN: El objetivo de este estudio fue revelar la morfometría del nervio mental o mentoniano para describir una zona segura y de esta manera, minimizar el daño de este nervio durante la tiroidectomía endoscópica transoral-abordaje vestibular (TOETVA). Este estudio se realizó en 12 cadáveres. Se realizó la localización del foramen mentoniano según los dientes, distancias surco gingival-labio (BG-L), foramen mentoniano-línea mediana (MF-Midline), foramen mentoniano-surco gingival (MF-BG), comisura-punto de ramificación (Cm-Br), punto de bifurcación - pro- yección vertical del punto de bifurcación en el labio inferior (Br - LVP), proyección vertical del punto de bifurcación en el labio inferior - comisura (LVP - Cm), comisura - línea mediana (Cm - línea mediana), ángulos del mentón (AM). Se registraron ramos angulares (AA) y labiales (AL) y patrones de ramificación. El tipo 1 se encontró principalmente como patrón de ramificación en el 45,8 %. Se describe un nuevo patrón de ramificación (tipo 9) encontrado en un cadáver. El foramen mentoniano se localizaba mayoritariamente a nivel de los segundos premolares. Según los resultados morfométricos, supero-lateral al curso de la rama angular e infero-medial al curso de la rama mentoniana del nervio mentoniano en el labio inferior, después de salir del foramen mentoniano, se describieron las zonas seguras, para la cirugía y preservación del nervio mentoniano y de sus ramos.

Factors affecting root migration after coronectomy of the mandibular third molar.

ABSTRACT: Nerve injury especially inferior alveolar nerve (IAN) is the one of the complications that occur when the mandibular third molar (M3) is extracted and in case of high risk patients, coronectomy might be an alternative to tooth extraction. The purpose of this retrospective study was to analyze root migration and its influencing factors at 6 months after coronectomy in both 2- and 3-dimensions using periapical view and cone-beam computed tomography (CBCT). We analyzed 33 cases of root remnant after coronectomy and measured the amount of migration in CBCT. The following factors that could possibly affect root migration were also analyzed: age, gender, number of M3 roots, shape of M3s, Pell, and Gregory classification, mesiodistal (MD) angulation, buccolingual (BL) angulation, contact point with the second molar, root curvature, and complete removal of the coronal portion. Migration of greater than 2 mm was found in 64% of the roots in the 2-dimensional (2D) analysis, and the average root migration was 4.11 mm in the 3-dimensional (3D) analysis. The factors affecting migration were the root morphology, complete removal of the coronal portion, impaction depth, and MD angulation in the 2D analysis, and MD and BL angulation in the 3D analysis. Ensuring sufficient space for root migration especially considering angulation, depth and complete removal of the coronal portion might be important factors after coronectomy of the M3. Root remnant after coronectomy of M3 may migrate in young patients who has sufficient empty coronal space and this may reduce the nerve damage by the separation of IAN and M3.

The α2δ-1-NMDAR1 interaction in the trigeminal ganglion contributes to orofacial ectopic pain following inferior alveolar nerve injury.

Orofacial ectopic pain can often arise following nerve injury. However, the exact mechanism responsible for orofacial ectopic pain induced by trigeminal nerve injury remains unknown. The α2δ-1 and glutamate N-methyl-d-aspartic acid receptor (NMDAR) interactions have been demonstrated to participate in neuropathic pain regulation in the spinal cord. In this study, a rat model of inferior alveolar nerve transection (IANX) was used to investigate the role of α2δ-1-NMDAR1 interaction in the trigeminal ganglion (TG) in regard to the regulation of orofacial ectopic pain. Western blot (WB) analysis indicated that α2δ-1 and NMDAR1 in the TG were substantially higher in IANX rats than they were in sham/naive rats. Additionally, immunofluorescence (IF) results revealed that α2δ-1 and NMDAR1 were co-expressed and distributed within neurons and activated satellite glial cells in the TG. Co-immunoprecipitation (Co-IP) results indicated that α2δ-1-NMDAR1 complex levels in the TG were higher in IANX rats than they were in sham rats. Furthermore, the results of behavioral tests demonstrated that intra-TG injection of gabapentin (α2δ-1 inhibitory ligand) or memantine hydrochloride (NMDAR antagonist) reversed the decrease in mechanical head-withdrawal threshold (HWT) in IANX rats. Moreover, inhibition of α2δ-1 by intra-TG administration of gabapentin suppressed the upregulation of the NMDAR1 protein, and the inhibition of NMDAR by intra-TG administration of memantine hydrochloride inhibited the increased expression of α2δ-1 protein induced by IANX. In conclusion, the physical and functional interaction between α2δ-1 and NMDAR1 is critical for the development of orofacial ectopic pain, indicating that α2δ-1, NMDAR1, and the α2δ-1-NMDAR1 complex may represent potential targets for the treatment of orofacial ectopic pain.

Microsurgical Repair of Inferior Alveolar Nerve Injuries Associated With Endodontic Treatment: Results on Sensory Function and Relief of Pain.

PURPOSE: An uncommon, but serious complication of endodontic treatment is inferior alveolar nerve (IAN) injury warranting operative intervention for exploration, debridement, and repair. The purpose of the study was to evaluate outcomes of microneurosurgical intervention for endotontic-related IAN injuries in terms of achievement of functional sensory recovery (FSR) and pain relief and to identify factors affecting outcomes. METHODS: A retrospective cohort study of patients who had microsurgical exploration and repair of IAN injuries sustained during endodontic therapy was performed. The primary predictor variable is time to surgery and the primary outcome variables were time to FSR, whether or not the patient regained FSR, and postoperative pain level at 12 months (1-10 on a visual analog scale). Secondary variables include intraoperative findings, surgical treatment rendered, sensory recovery, and preoperative pain level. Analyses include Kaplan-Meier estimation, Fisher exact test, 1-way and mixed-design analysis of variance, and paired t-test. RESULTS: The sample included 23 patients with a mean age of 48.6 years with a female:male ratio of 20:3. Painful sensation was present in 17 (73.9%) of 23 patients at initial consultation. Mean time to surgery was 10.9 months (median 4.8 months, standard deviation = ±16.9). FSR was achieved in 10 of 21 patients at 1 year. Pain level at 1 year following surgical intervention improved from 4.86 to 2.76 (P = .001) with no effect from other variables. CONCLUSIONS: Surgical exploration and repair of endodontic-related IAN injuries is shown to improve neuropathic pain levels, while only delivering a modest recovery of sensory function. These injuries can be severe and debilitating and present with a variety of diagnoses and surgical findings. While this study fails to identify any particular factors affecting outcome, the data presented can help with clinician recommendations for treatment in patient-centered care.

Safety and surgical outcomes of transoral endoscopic thyroidectomy vestibular approach for papillary thyroid cancer: A two-centre study.

OBJECTIVE: The transoral endoscopic thyroidectomy vestibular approach (TOETVA) has been increasingly used to treat patients with papillary thyroid cancer (PTC) with improved cosmetic outcomes. This study aimed to explore the safety and efficacy of TOETVA in patients with PTC. MATERIALS AND METHODS: This retrospective study included TOETVA patients from Yantai Yuhuangding and Xiamen Zhongshan Hospitals. Among the 297 patients studied, 84 had benign nodules (28.3%), 208 had PTC (70.0%), and five had follicular thyroid cancer (1.7%). RESULTS: The incidence of transient and permanent recurrent laryngeal nerve injury was 1.3%, while that of transient hypoparathyroidism was 1.0%. Mental nerve paraesthesia was observed in 241 cases (81.1%), while permanent mental nerve paraesthesia was noted in seven cases (2.4%). Abnormal motor function of the lower lip and chin was observed in 12 cases (4.0%). Ten of the 208 patients with PTC (4.8%) underwent total thyroidectomy (TT) and bilateral central neck dissection (CND). A mean 6.6 ± 4.1 and 10.9 ± 4.0 lymph nodes were removed in the unilateral and bilateral surgeries, respectively, with a metastasis rate of 49.0%; a mean 2.7 ± 2.3 and 3.2 ± 2.6 lymph nodes were metastatic, respectively. The parathyroid gland was inadvertently removed in 6.6% and auto-transplanted in 10.6% of patients with unilateral PTC. The non-stimulated thyroglobulin level in the TT and bilateral CND patients was below 1 ng/mL at the 6-month follow-up. CONCLUSION: TOETVA is safe in well-selected patients with unilateral PTC. However, its safety remains unclear in patients treated with TT and bilateral CND.

Numb chin syndrome in sickle cell disease: a case series of Jamaican patients.

Numb chin syndrome is an uncommon presentation that has been reported as secondary to metastatic disease, trauma, and infections of the maxilla, mandible, or oral cavity. The hypoesthesia, paraesthesia, or pain are a result of injury to the inferior alveolar nerve, which is particularly vulnerable as it exits the mandible through the mandibular foramen as the mental nerve. In persons with sickle cell disease, it has been reported as a manifestation of mandibular vaso-occlusive crisis. This case series presents 13 patients with sickle cell disease who presented with numb chin syndrome, the largest number of cases that has been described in the literature to date. The report illustrates the wide variety of presentations and therefore possible differential diagnoses to consider. In this case series, the symptoms were associated with vaso-occlusive crises, allergic reactions, dental infections, malignancy, rheumatoid arthritis, and pregnancy. Most appeared to be self-limiting; however, one patient was having his second episode, and the numbness has persisted in three patients. The series illustrates that it is important not only to ensure that the source of the local vaso-occlusive crisis is treated, but also to not miss important differentials such as metastatic disease, where this can be the first presentation of malignancy and would represent a very poor prognosis. There is no reported successful treatment for the hypoesthesia in this case series, and this presents an area for further research.

Activation of oxytocin receptor in the trigeminal ganglion attenuates orofacial ectopic pain attributed to inferior alveolar nerve injury.

This study explores the effects of oxytocin receptor (OXTR) in the trigeminal ganglion (TG) on orofacial neuropathic pain. We demonstrate that OXTR activation in the TG relieves the orofacial ectopic pain as well as inhibits the upregulated expression of calcitonin gene-related peptide (CGRP), IL-1ß, and TNFα in the TG and spinal trigeminal nucleus caudalis (SpVc) of rats with inferior alveolar nerve transection. OXTR, a G protein-coupled receptor, has been demonstrated to play a significant role in analgesia after activation by its canonical agonist oxytocin (OXT) in the dorsal root ganglion. However, the role of OXTR in the trigeminal nervous system on the orofacial neuropathic pain is still little known. In the present study, we aimed to investigate the regulation effect and mechanism of OXTR in the TG) and SpVc) on orofacial ectopic pain induced by trigeminal nerve injury. The inferior alveolar nerve (IAN) was transected to establish a ectopic pain model. A behavioral test with electronic von Frey filament demonstrated IAN transection (IANX) evoked mechanical hypersensitivity in the whisker pad from day 1 to at least day 14 after surgery. In addition, administration of OXT (50 and 100 µM) into the TG attenuated the mechanical hypersensitivity induced by IANX, which was reversed by pretreatment with L-368,899 (a selective antagonist of OXTR) into the TG. In addition, immunofluorescence showed the expression of OXTR in neurons in the TG and SpVc. Furthermore, Western blot analysis indicated that the upregulated expression of OXTR, CGRP, IL-1ß, and TNFα in the TG and SpVc after IANX was inhibited by the administration of OXT into the TG. And the inhibition effect of OXT on the expression of CGRP, IL-1ß, and TNFα was abolished by preapplication of OXTR antagonist L-368,899 into the TG.NEW & NOTEWORTHY This study explores the effects of oxytocin receptor (OXTR) in the trigeminal ganglion (TG) on orofacial neuropathic pain. We demonstrate that OXTR activation in the TG relieves the orofacial ectopic pain as well as inhibits the upregulated expression of calcitonin gene-related peptide, IL-1ß, and TNF-α in the TG and spinal trigeminal nucleus caudalis of rats with inferior alveolar nerve transection.

Avoiding Inferior Alveolar Nerve Injury during Osseous Genioplasty: A Guide for the Safe Zone by Three-Dimensional Virtual Imaging.

BACKGROUND: No consensus exists about the safest position for performing the osseous genioplasty, with 5 to 6 mm below the mental foramen being the most frequently recommended position. This study intends to generate a safe distance guide to minimize the risk of inferior alveolar nerve injury during osteotomy. METHODS: Pretreatment cone-beam computed tomography-derived three-dimensional models from adult patients with skeletal class I to III patterns and cleft lip/palate deformity who underwent orthodontic-surgical interventions (n = 317) were analyzed. A three-dimensional vertical distance between the inferior margin of the mental foramen and the lowest point of the inferior alveolar nerve canal was measured in each three-dimensional hemimandible (n = 634). Statistical analysis was performed to generate the safe distance guide in a stepwise fashion at 95, 99, and 99.99 percent confidence levels. RESULTS: Class III (4.35 ± 1.42 mm) and cleft lip/palate (4.42 ± 1.53 mm) groups presented significantly (p < 0.001) larger three-dimensional distances than class I (3.44 ± 1.54 mm) and class II (3.66 ± 1.51 mm) groups. By considering the 5- to 6-mm safe distance parameter, 6.4, 5.0, 10.6, 16, and 9.9 percent of hemimandibles were at risk of osteotomy-induced nerve injury in the class I, class II, class III, cleft lip/palate, and overall cohorts, respectively. Overall, the safe distance zone to perform the osteotomy was set at 7.06, 8.01, and 9.12 mm below the mental foramen, with risk probabilities of 2.5, 0.5, and 0.0005 percent, respectively. CONCLUSION: This study contributes to patient safety and surgeon practice by proving a safe distance guide for genioplasty.

Anatomic Variations From 120 Mental Nerve Dissections: Lessons for Transoral Thyroidectomy.

BACKGROUND: Transoral endoscopic thyroidectomy vestibular approach (TOETVA) is a promising technique for eliminating a neck incision. A new risk of TOETVA is the potential for injury to the mental nerves during placement of three oral endoscopic ports. A better understanding of the variations in mental nerve anatomy is needed to inform safer TOETVA technique. MATERIALS AND METHODS: We performed 120 dissections of mental nerve branches exiting the mental foramen in 60 human cadavers. Anatomic distances and relationships of the foramen to the midline were evaluated. Mental nerve branching patterns were studied and compared with previously reported classification systems to determine surgical safe zones free of nerve branches. RESULTS: The mean midline-to-mental foramen distance was 29.2 ± 3.3 mm, with high variability across individuals (18.8-36.8 mm). There were differences in this distance between the left and right foramina (29.8 ± 3.2 versus 28.8 ± 3.3 mm, P = 0.03). All mental nerve branches exiting the mental foramen distributed medially. The branching patterns were classified into eight distinct categories, three of which are previously undescribed. One of these novel patterns, occurring in 9.2% of cases, had a dense and wide clustering of branches traveling toward the midline. CONCLUSIONS: The location of the mental foramen and mental nerve branching patterns demonstrate high variability. To avoid mental nerve injury in TOETVA, we identify a safe zone for lateral port placement lateral to the plane of the mental foramen. Placement and extension of the middle port incision should proceed with caution, as clustering of mental nerve branches in this area can frequently be present.

Relação da exodontia de terceiros molares e a ocorrência de parestesia do nervo alveolar inferior: uma revisão narrativa / Relationship of third molar extraction and occurrence of lower alveolar nerve paresthesia: a narrative review

Terceiros molares inferiores podem apresentar uma estreita relação com o nervo alveolar inferior, aumentando as chances de lesão durante o ato cirúrgico. Objetivo: descrever a relação entre a exodontia de terceiros molares e a ocorrência da parestesia do nervo alveolar inferior. Revisão de literatura: cirurgia para exodontia de dentes terceiros molares é o procedimento mais frequentemente realizado entre as cirurgias bucais e, como todo tipo de cirurgia, possui riscos e acidentes e/ou complicações que podem acometer os pacientes tal como a parestesia. Esta é uma condição que altera a sensibilidade de determinada área e pode ocorrer em consequência de traumas diretos ao nervo ou pela compressão deste, devido a hematoma e edema, levando a desconforto e incômodo. Considerações finais: é importante o profissional cirurgião-dentista atentar para o planejamento correto, criterioso e fazer uso de exames complementares, a fim de precaver possíveis complicações durante o ato cirúrgico. Caso a parestesia aconteça, podem ser utilizados tratamentos medicamentosos, a laser ou cirúrgicos, com resultados em longo prazo positivos e reversão do caso.(AU)

Lower third molars may present a close relation with the inferior alveolar nerve increasing the chances of injury during the surgical act. In view of this, this literature review aims to describe the relationship between the extraction of molars third and the occurrence of inferior alveolar nerve paresthesia. Paresthesia is a condition that alters the sensitivity of a certain area and can occur as a result of direct trauma to the nerve or compression of the nerve due to hematoma and edema. It leads to discomfort and discomfort, and it is important for the professional to attend to the correct, judicious planning and to make use of complementary exams. If paraesthesia occurs, medical, laser or surgical treatments are used, with positive long- -term results and reversal of the case. (AU)