BACKGROUND: The analgesia after lower third molar alveolectomy is based on the use of non-steroidal anti-inflammatory drugs (NSAIDs) that have significant risks, and are contraindicated in the third trimester of pregnancy. Aiming to reduce NSAIDs use after this surgery, we quantified analgesic effects of ultrasound (US)-guided extraoral mandibular nerve block.
METHODS: Thirty-six patients were equally allocated to the experimental or control group, based on their willingness to receive experimental US-guided extraoral mandibular nerve block for postoperative analgesia. The experimental block applied prior to lower third molar alveolectomy, was followed by standard intraoral inferior alveolar nerve block. In the control group, patients received only intraoral block of inferior alveolar nerve. All patients reported pain level (visual analogue scale, VAS) right after the application of blocks. The next day, patients reported duration of pain-free time and the use of analgesic.
RESULTS: The US-guided extraoral mandibular nerve block prolonged the pain-free time to 8 h (vs. 4 in control group, P < 0.001) and reduced NSAIDs use (12 patients needed analgesic in experimental vs. 17 patients in control group, P = 0.038). The application of experimental block was less painful (VAS = 2) than the application of intraoral inferior alveolar nerve block (VAS = 4, P = 0.011). In 8/18 patients in the experimental group US-guided extraoral mandibular nerve block solely achieved adequate surgical anesthesia.
CONCLUSIONS: US-guided extraoral mandibular nerve block prolonged pain-free period and reduced the use of NSAIDs after lower third molar alveolectomy, thus proving to be successful analgesia method for this dental surgery.
BACKGROUND: https://classic.
RESULTS: gov/ct2/show/NCT06009302 , identification number: NCT06009302, date of registration: 18/08/2023.

UNASSIGNED: Mandibular reconstruction has historically been challenging due to the complex, highly functional, and esthetic nature of the anatomy. The most common etiologies of these defects requiring resection include trauma, benign tumors, and malignant pathology. Mandibular defects have been treated with little consideration for neural reconstruction, leaving patient\'s orally incompetent with associated social stigma. Although recent advances in reconstructive techniques improve oral rehabilitation, immediate inferior alveolar nerve (IAN) reconstruction has not been widely adapted.
UNASSIGNED: Here-in we seek to discuss the innovations of neural reconstruction of large segment mandibular defects and associated IAN defects and present an example case performed at Naval Medical Center San Diego (NMCSD).
UNASSIGNED: Pertinent literature discussing maxillofacial reconstruction and nerve repair using autogenous nerve harvest and allograft was queried from available online resources.
UNASSIGNED: Six patients have received immediate reconstruction of the IAN using processed nerve allograft over the past three years. All obtained sensation to S3 within six months of surgery.
UNASSIGNED: IAN repair using nerve allografts in conjunction with free flap reconstruction for large mandibular defects is a viable treatment and should be the new paradigm in maxillofacial reconstruction as it provides substantial quantifiable and qualitative improvements in social, functional, and esthetic outcomes of care.

OBJECTIVE: The aim of the study is reducing the risks of surgical injury to the inferior alveolar nerve, by taking into account individual topographic and anatomical features, improving diagnostic methods, and techniques for removing retinated teeth with a close fit to the mandibular canal.
METHODS: An examination was conducted in the Department of Surgical Dentistry (CBCT/OPG) and surgical treatment of 223 patients, with a close fit of the roots of the retinated lower third molar to the mandibular canal. Microslips of teeth with roots intact during removal (n=96) of the main group and the control group (n=52) were prepared with a Micromet Remet manual petrographic machine. The sections were carried out along the longitudinal axis of the tooth with the capture of the area of close fitting of the nerve, the teeth from the control group were sawed longitudinally along the axis of the root. The measurement of the macroanatomic features of the roots was carried out with a micrometer (MCC-MP-100 0.001 electronic «CHEESE», manufactured in the Russian Federation), measurements of the thickness of dentine and cement tissues on macroglyphs were carried out using a microscope calibration ruler with an accuracy of 0.01 mm.
RESULTS: In the main group, three types of attachment of the mandibular canal to the root of the third molars were distinguished: 20 (96) cases of inter-root attachment of the mandibular canal, 42 (96) apical, 34 (96) lateral (buccal and lingual). A number of anomalies in the structure of the roots of the third molars have been revealed, which are a factor in injury to the neurovascular bundle of the mandibular canal during tooth extraction. The surface of the roots, as well as the microscopes of the tooth sections adjacent to the mandibular canal, were studied under a microscope.
CONCLUSIONS: A number of specific anomalies of the roots of retinated third molars formed by root dilaceration, thinning of cement tissues, hypercementosis, which are formed at the site of the mandibular canal.In the presence of a deep indentation on the root of the tooth, as well as in the presence of areas of apical hypercementosis in the form of a «spike», the probability of nerve injury during tooth extraction increases many times, which must be taken into account when removing retinated third molars.
UNASSIGNED: Снижение риска операционной травмы нижнего альвеолярного нерва путем учета индивидуальных топографо-анатомических особенностей, совершенствования способов диагностики и техники удаления ретинированных зубов с тесным прилеганием к нижнечелюстному каналу (НЧК).
UNASSIGNED: В отделении хирургической стоматологии проведены обследование (конусно-лучевая компьютерная томография/ортопантомограмма) и хирургическое лечение 223 пациентов с тесным прилеганием корней ретинированного нижнего третьего моляра к НЧК. Микрошлифы зубов с неповрежденными при удалении корнями (n=96) основной группы и группы контроля (n=52) приготавливали ручным петрографическим станком Micromet Remet. Срезы проводили продольно оси зуба с захватом области тесного прилегания нерва, зубы из группы контроля распиливали продольно оси корня. Измерение макроанатомических особенностей корней проводили микрометром (МКЦ-МП-100 0,001 электронный ЧИЗ, РФ), измерения толщины тканей дентина и цемента на макрошлифах — с помощью калибровочной линейки микроскопа с точностью до 0,01 мм.
UNASSIGNED: В основной группе выделено 3 типа прилегания НЧК к корню третьих моляров: 20 случаев межкорневого, 42 — апикального и 34 — бокового (щечного и язычного) прилегания НЧК. Выявлен ряд аномалий строения корней третьих моляров, которые являются фактором травмы сосудисто-нервного пучка НЧК при операции удаления зуба. Под микроскопом изучена поверхность корней, а также микрошлифы участков зуба в месте прилегания к НЧК.
UNASSIGNED: Выявлен ряд специфических аномалий корней ретинированных третьих моляров, образованных дилацерацией корней, истончением тканей цемента, гиперцементозом, которые формируются в месте прилегания НЧК. В случае глубокого вдавления на корне зуба, а также наличия участков апикального гиперцементоза в виде «шипа» многократно увеличивается вероятность травмы нерва при операции удаления зуба, что необходимо учитывать в ходе удаления ретинированных третьих моляров.

BACKGROUND: Iatrogenic mandibular nerve damage resulting from oral surgeries and dental procedures is painful and a formidable challenge for patients and oral surgeons alike, mainly because the absence of objective and quantitative methods for diagnosing nerve damage renders treatment and compensation ambiguous while often leading to medico-legal disputes. The aim of this study was to examine discriminating factors of traumatic mandibular nerve within a specific magnetic resonance imaging (MRI) protocol and to suggest tangible diagnostic criteria for peripheral trigeminal nerve injury.
METHODS: Twenty-six patients with ipsilateral mandibular nerve trauma underwent T2 Flex water, 3D short tau inversion recovery (STIR), and diffusion-weighted imaging (DWI) acquired by periodically rotating overlapping parallel lines with enhanced reconstruction (PROPELLER) pulse sequences; 26 injured nerves were thus compared with contra-lateral healthy nerves at anatomically corresponding sites. T2 Flex apparent signal to noise ratio (FSNR), T2 Flex apparent nerve-muscle contrast to noise ratio (FNMCNR) 3D STIR apparent signal to noise ratio (SSNR), 3D STIR apparent nerve-muscle contrast to noise ratio (SNMCNR), apparent diffusion coefficient (ADC) and area of cross-sectional nerve (Area) were evaluated.
RESULTS: Mixed model analysis revealed FSNR and FNMCNR to be the dual discriminators for traumatized mandibular nerve (p < 0.05). Diagnostic performance of both parameters was also determined with area under the receiver operating characteristic curve (AUC for FSNR = 0.712; 95% confidence interval [CI]: 0.5660, 0.8571 / AUC for FNMCNR = 0.7056; 95% confidence interval [CI]: 1.011, 1.112).
CONCLUSIONS: An increase in FSNR and FNMCNR within our MRI sequence seems to be accurate indicators of the presence of traumatic nerve. This prospective study may serve as a foundation for sophisticated model diagnosing trigeminal nerve trauma within large patient cohorts.

The high frequency and complexity of mandibular third molar (M3M) surgery have led several authors to the development of classification systems for better evaluation and management in oral surgery. This study compared the classifications of Juodzabalys and Daugela et al. (JD), Sammartino et al., Chang et al., Jhamb et al., Maglione et al., and Nemsi et al. to understand the concordance between the scores of M3M surgery. Two types of analysis were conducted: the relationship between the M3M and the inferior alveolar nerve (IAN), and the overall difficulty score based on the tooth\'s angulation and its spatial position with the adjacent structure. The analysis of the classifications on the relationship between M3M and IAN resulted in a concordance of 26.1%. In the pairwise comparisons, the classifications of Nemsi et al. and Jhamb et al. showed the highest concordance of 59.5%. Analyzing the total scores difficulty, the JD et al., Chang et al., and Sammartino et al. classifications demonstrated a concordance level of 25.5%. A pairwise assessment revealed a higher concordance degree between the classifications of Sammartino et al. and Chang et al. (57.4%). The results highlight the limits in establishing a comprehensive and objective classification for the surgical difficulty of M3M, possibly attributed to variations in the methodology for computing total scores. An objective, automated, and non-operator-dependent classification method for assessing the surgical difficulty of M3M is still needed.

UNASSIGNED: The mental nerve, the extended part of the inferior alveolar nerve, is often injured during dentoalveolar, orthognathic, or tumor surgery. Numerous therapeutic interventions, including surgery and pharmacotherapy, have been used to enhance the recovery of nerve injuries. Dental pulp stem cells (DPSCs) represent an easily accessible source of adult stem cells that can be isolated from the pulp of extracted teeth. This study evaluated the effect of DPSCs on the regeneration of the mental nerve injury model of rabbits.
UNASSIGNED: In this presented study, DPSCs were cultured and cell characterizations were performed by using flow cytometry and immunostainings. Bilateral mental nerve injury models of rabbits were created. In the control group (n = 10), saline was applied, and in the study group (n = 10), 2 × 106 DPSCs were applied to the repaired nerve areas. After 3 weeks, animals were killed and histological examination was obtained by using Masson\'s trichrome staining. An unpaired Student\'s t test was used when comparing the groups. Differences were considered to be statistically significant at P values of less than 0.05.
UNASSIGNED: The DPSCs demonstrated a homogeneous population of mesenchymal stromal cells which expressed cluster of differentiation CD44, CD73, CD90, and CD105 and lack of CD34, CD45, and HLA-DR. Our finding clearly demonstrated that a lower number of cross-sectioned axons were founded in the control group (60.18 ± 2.52) compared to the study group (72.96 ± 2.43) (p = 0.00).
UNASSIGNED: DPSCs promote mental nerve axonal regeneration. These results suggest that DPSCs provide an important accessible source of adult stem cells for mental nerve regeneration.

OBJECTIVE: The aim of this study is to delineate the safety zone concerning the anteriorization of the AL and correlate it with the behavior of the AL, analyzing its feasibility.
METHODS: Adhering to the Joanna Briggs Institute (JBI) manual guidelines, both the protocol and this review were conducted based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR) checklist. MeSH terms, combined with free terms, were utilized to search for articles in the following databases: Embase, LILACS, LIVIVO, PubMed/MEDLINE, Scopus, Web of Science, and grey literature.
RESULTS: Fifteen articles were select following the eligibility criteria. An average safe zone of 4.75 mm in humans was observed, with a prevalence 60.8% and average anterior length of the AL of 2.09 mm in humans.
CONCLUSIONS: The AL has varied patterns across different populations, then, it could not be asserted a 100% safe zone. Preoperative analysis of the AL with CBCT is always necessary. While it could be stated that a safe zone should be employed as an inviolable region, stipulated measures of a safe zone should be regarded as an area of greater attention in preoperative planning.

OBJECTIVE: To identify and measure the distance from the dental apices to the mandibular (MC) and mandibular incisive (MIC) canals, the diameter of the MC and the distances of the mental foramen (MF).
METHODS: In this retrospective study, cone-beam computed tomography scans of 144 adult patients (males and females) from a dental school in South Brazil were evaluated. Cross-sections were selected on the MC and the MIC paths, perpendicular to the mandibular base, and measurements were taken from the dental apices to the mandibular cortices. The measurement and location of the mandibular and mental foramen on both sides were compared. Paired t-tests compared sides, while Student\'s t-tests compared sexes (P < 0.05).
RESULTS: The distance from the dental apices to the upper wall of the MC was closest in the third molar and farthest in the central incisor region. In both sexes and sides, the path of the MC is in most cases lingually in the molar regions and moves to the buccal region from the second premolar. The MF emerges in the regions between the premolars or near the second premolar.
CONCLUSIONS: The results of this study highlight the importance of evaluating specific individual characteristics of a given population.

BACKGROUND: The mandibular foramen (MnF) and the mental foramen (MF) are essential anatomical landmarks that should be considered before any surgical procedures in the mandible. This study aimed to investigate the characteristics of the MnF and MF in relation to adjacent anatomical structures, as well as age and gender differences, using cone beam computed tomography (CBCT) projections.
METHODS: The study was conducted from August 2023 to January 2024 at the Can Tho University of Medicine and Pharmacy Hospital, Vietnam. In this retrospective study, 50 CBCT images of Vietnamese patients were randomly taken for various clinical purposes. Furthermore, relevant data, such as gender and age groups, were selected to evaluate the correlations, along with specific inclusion criteria. Patients within the age range of 18-69 with a symmetrical mandible were included.
RESULTS: The distance of the MnF-MN was 29.6±5.0 mm (right) and 30.1±4.6 mm (left) in males and 25.0±4.2 mm (right) and 26.3±5.0 mm (left) in females. The distance of the MnF-posterior border of the ramus (P) was 16.2±3.6 mm (right) and 15.0±2.3 mm (left) in males. For females, it was 17.1±2.9 mm (right) and 13.8±1.7 mm (left). The distance of the MF-body mandible (MB) was 15.4±2.4 mm (right) and 15.6±2.0 mm (left) in males and 14.0±2.1 mm (right) and 14.3±1.6 mm (left) in females. The distance of the MF-mandibular midline (MM) was 27.0±2.6 mm (right) and 27.0±2.9 mm (left) in males and 25.3±2.0 mm (right) and 25.1±2.2 mm (left) in females. These distances showed statistically significant differences depending on gender (P<0.05).
CONCLUSIONS: It can be said that CBCT provides comprehensive information about the MnF and the MF for dentists in research and clinical practice.

The present study aimed to evaluate the degree of nerve injury on inferior alveolar nerve (IAN) by different implant drills resulting from direct canal intrusion into inferior alveolar canal (IAC). A cadaveric study involving 7 human mandibles was performed to evaluate mechanical injury of canal enclosed IAN resulting from different drills. In group 1, osteotomies were created using different drills with 1 mm of intracanal intrusion, simulating accidental drill intrusion into canal. In group 2, drilling was stopped when the tip has breached into IAC, limited by tactile feedback of operator. The depth and width of nerve defects were assessed using optical coherence tomography. A significant difference in defect depth was found (p < 0.001) in group 1. A sinus lift reamer inflicted the least damage (0.068 ± 0.022 mm). It was also found that the mean defect depth was significantly different when a twist drill was used (p = 0.016). Sinus lift reamer can be used safely for osteotomy preparation in mandible when bone height is limited or when radiographic visualization of canal is poor. Bone corticalization around IAC does not provide adequate protection for IAN in the event of accidental intracanal intrusion.