Anterior Belly Of Digastric Muscle Research Articles

Comparison between botulinum toxin type A injection on masseter muscle only and additional injection on anterior belly of digastric muscle in sleep bruxism patients: A clinical trial.

This study aims to evaluate the effects on bite force and muscle thickness of the botulinum toxin (BoNT) injection for patients with sleep bruxism (SB) by comparing injections into the masseter muscle only and both the masseter and the anterior belly of the digastric muscle (ABDM) in a clinical trial. Twelve SB patients received BoNT-A injections using US-guided techniques into the masseter muscle only (Group A), while the remaining 12 SB patients received injections into both the masseter and ABDM (Group B). Bite force and muscle thickness were measured before injection, as well as 1 and 2 months after injection. The bite force and masseter muscle thickness decreased in both Group A and Group B before injection, and at 1 and 2 months after injection. However, there was no significant difference (p > .05, repeated measures analysis of variance) between the two groups, and there was also no significant difference in ABDM thickness (p > .05, repeated measures analysis of variance). This study is the first to assess the short-term effects of BoNT injected into ABDM for SB control. Results show no influence on SB reduction, suggesting the need for further research on BoNT's effectiveness in controlling intense ABDM contractions during sleep and assessing suprahyoid muscle potential impact on rhythmic masticatory muscle activity occurrence.

Double Chin Concerns afterEn Bloc Mandibular U-ShapedOsteotomy: Submental-Cervical Soft Tissue Changes and Anterior Belly of Digastric Muscle Assessment.

To assess submental-cervical soft tissue changes afteren bloc mandibularU-shapedosteotomy and examine alterations in the anterior belly of digastric muscle (ABDM). A retrospective study analyzed 20 patients who underwent en bloc mandibularU-shaped osteotomy from 2018 to 2023. Preoperative (Tp) and long-term follow-up (Tf) CT data were collected for analysis, measuring mandibular volume, soft tissue thickness at menton (Mes) and cervicale (C), and ABDM parameters (length, cross-sectional area (CSA), volume, distance from centroid point to the mandibular margin). Correlation analyses were performed to investigate the connection between soft tissue thicknesschanges, ABDM changes, and mandibular osteotomy volume. Long-term follow-up revealed a significant increase in soft tissue thickness at the Mes and C points after U-shaped mandibular osteotomy, especially at the C point. The adaptive length of ABDM decreased, CSA increased, and volume decreased, but the ABDM centroid point shifted downward relative to the mandibular margin, indicating drooping protrusion. The increment of soft tissue thicknesswas moderately positively correlated with the amount of osteotomy, and the decrement of ABDMlength and volume were slightly positively correlated with the amount of osteotomy. The degree of soft tissue relaxation afterU-shaped osteotomy is related to the extent of osteotomy. Notably, the protrusion of ABDM relative to the mandibular margin affects submental-cervical contour aesthetics. Prior to U-shaped osteotomy, it is crucial to assess the soft tissue condition of the patient's lower face, and the individualized design of the osteotomy volume should be carried out cautiously and safely. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Morphological study of the anatomical variations of anterior belly of digastric muscle in Brazilian cadavers.

Cases of variations in anterior belly of the digastric muscle must be carefully identified to avoid misinterpretations and assist in the correct surgical or aesthetic procedure and help in the teaching of anatomy. The aim of this study was to describe the anatomical variations of anterior belly of digastric muscle in Brazilian cadavers. Thirty-one human heads were selected, from adult cadavers (18-80 years, 29 males and 2 females). The morphology of the anterior belly of the digastric muscle was observed, identifying the possible anatomical variations that were characterised and classified according to the amount of muscle bellies, fibre direction and place of origin and insertion. The morphometric measurements were performed using a digital calliper. To analyse the data obtained, photographic documentation, anatomical description and individual morphometric description of each muscle belly were performed. The incidence of anatomical variation was obtained in percentage (%). The anatomical variation of the anterior belly of the digastric muscle was present in 6 cadavers (19.31%; 1 female and 5 male). All anatomical variations presented an accessory belly to the anterior belly. However, these accessory bellies were configured differently in the location, direction of muscle fibres and in their dimensions (length and width). The gross anatomy of the anterior belly of the digastric muscle and their variations is important to assist in surgical procedures, pathological or diagnostic function. In addition, asymmetrical variations in the submental region must be carefully identified to avoid misinterpretations.

Surface Electromyographic Analysis of Masticatory and Neck Muscles in Skeletal Class II Division 1 Malocclusion with EMG Indices - A In Vivo Study

Background amp Objectives To evaluate the activity of oro-facial and neck muscles in skeletal class II division 1 malocclusion with horizontal and vertical growth patterns using surface electromyography.Methods Twenty non-growing patients comprising males and females 18-30 years were selected and grouped into horizontal and vertical growth patterns using lateral cephalograms. sEMG of masseter temporalis sternocleidomastoid and anterior belly of digastric muscles were performed and percentage overlapping coefficient activity Index asymmetry Index and torque Index were recorded.Results The percentage overlapping coefficient was recorded as 112.3 in horizontal and 92.35 in vertical growers. The activity index for horizontal growers was 14.28 microVsec indicating a predominance of the masseter muscle and in vertical growers it was -8.94 microVsec indicating a predominance of anterior temporalis. The asymmetry index for horizontal growers observed was 17.75 microVsec indicating the predominance of rightside muscles and was -10.77 microVsec showing the dominance of left-side muscles in vertical growers. Torque index in horizontal and vertical growth patterns were 24.56 and -43.76 respectively inferring a right-sided mandibular movement in horizontal growers and vice versa. The mean value of sternocleidomastoid muscle observed was 18.74 microVsec in horizontal growers and 14.15 microVsec in vertical growers. The mean values of the anterior belly of digastric muscles were 18.87 microVsec in horizontal growth pattern and 19.57 microVsec in vertical growers.Conclusion There was symmetry between muscles and an increased predominance of the masseter group in horizontal growers while an increased predominance of the temporalis muscle was observed in vertical growers. There was increased activity of right-sided muscles and right-sided mandibular movement in horizontal growers while an increased activity of left-sided muscles and left-sided mandibular movements was noted in vertical growers.

Repair of postoperative defects of oral cancer with submental island flaps based on vascular pedicles of different states: a multicenter retrospective study

Submental island flap has certain advantages in repairing postoperative defects of oral cancer, and it can often achieve similar or even better effects compared with those of the free tissue flap. In this study, according to the different characteristics of patients and postoperative defects of oral cancer, submental island flaps with different states of vascular pedicle were prepared, and its repair methods, safety, and clinical effects in treating postoperative defects of oral cancer were investigated. 83 patients with oral cancer who met the inclusion criteria were selected. According to the different characteristics of the patients and postoperative defects of oral cancer, the traditional submental island flap vascular pedicle was modified into three different states: submental artery perforator flap, vascular pedicled flap with the anterior belly of digastric muscle but without the submandibular gland (SIF with anterior belly of DM), and vascular pedicled flap with the anterior belly of the digastric muscle and the submandibular gland (SIF with anterior belly of DM and SG). The types of the submental artery and the drainage vein, flap survival, and complications, were observed. The flap was successfully harvested for all patients, and the submental artery could be found or separated for all of them, with the venous drainage to the internal jugular vein in 57 (57/83, 68.67%), to the external jugular vein in 18 (18/83, 21.69%), and to the anterior jugular vein in eight (8/83, 9.64%) cases. Submental artery perforator flap was used for 11 cases, complete necrosis occurred in two cases (2/11, 18.18%), partial necrosis occurred in one case (1/11, 9.09%); SIF with anterior belly of DM was used for 49 cases, complete necrosis occurred in one case (1/49, 2.04%), partial necrosis occurred in four cases (4/49, 8.16%); SIF with anterior belly of DM and SG was used for 23 cases, including chimeric flap combining the submental island flap and the submandibular gland used for 15 cases, there were no cases of complete or partial necrosis. Submental island flap was effective in repairing postoperative defects of oral cancer. Submental island flaps with three different states of vascular pedicle could repair oral cancer-affected tissues with different defect characteristics.

Mylohyoid nerve revisited

The mylohyoid nerve is also called nerve to mylohyoid (muscle). This nerve is a branch from the inferior alveolar nerve, which is very familiar to our dentists due to the frequently used block anesthesia for mandibular tooth treatment. The motor fiber is known to be the main component of the nerve that is distributed in the my-lohyoid muscle and anterior belly of digastric muscle. In this review article, the following contents will be discussed: the naming story based on the etymology, the general route and main function of the nerve, the research related to the failure of inferior alveolar nerve block anesthesia, and finally other miscellaneous anatomical research results and their clinical significance.

P.129 Radiofrequency rhizotomy for trigeminal neuralgia under general anaesthetic with intraoperative neuromonitoring

Background: Radiofrequency rhizotomy is an efficacious technique for treatment of trigeminal neuralgia that is classically performed with the patient awake. Previous studies have investigated methods for both anatomic and neurophysiologic optimization for nerve targeting. Methods: We performed a retrospective review of prospectively collected data on patients undergoing radiofrequency rhizotomy under a general anesthetic. Electrodes are placed in the temporalis, masseter and one of mylohyoid or anterior belly of digastric muscles. We then localize of the correct subdivision of the trigeminal nerve. The division of the trigeminal nerve with pain shows a muscle response, which is not present in normal subdivisions. Results: A total of 23 radiofrequency rhizotomies were performed under general anesthetic. Abnormal conduction reflexes were present in all cases, and dissipated after lesioning. Pre-operative BNI pain scores were 4.1 ± 0.3, which dropped to 1.8 ± 1.9 post-op (p=0.003). Number of pain medications (2.9 ± 0.6 v. 1.3 ± 1.3, p=0.007) and number of patients with opioid usage (78.7% v. 21.7%, p=0.007) both decreased after rhizotomy. Conclusions: Using a novel conduction pathway, we have successfully been able to monitor radiofrequency rhizotomy in patients operated on under a general anesthetic, with promising preliminary results. Further work is needed to better evaluate this intervention.

Lower lip depressor reanimation using anterior belly of digastric muscle transfer improves psychological wellbeing in facial palsy patients

The authors previously published positive peer-reviewed (21 raters using the Terzis scale) and photogrammetric (Emotrics) outcomes in patients who had undergone two-stage lower lip reanimations up to 2018. Other series have published surgeon and peer-rated results, but we know of only two (n=12) that have assessed patients’ views using patient satisfaction surveys. This paper presents patient-rated outcomes (PROMS) in an 11-year series of both single and two-stage anterior belly of digastric muscle (ABDM) lower lip reanimations. Demographics, paralysis characteristics, operative details, and complications were recorded. Patients were telephoned and requested to complete the Glasgow Benefit Inventory (GBI) to assess patient-rated outcomes. Thirty-two patients were eligible (mean age 36.4 years). Twenty-one (63.6%) completed the GBI (mean score +33.3). More patients reported benefit than detriment (95.2% vs 4.8%). Complications were infrequent and included three cases of superficial infections and one of dermatitis. Four patients (12.5%) underwent minor revisions, mostly lipofilling of lip notches. The median (range) duration of follow up was 2.8 (0.3 – 8.5) years. ABDM transfer for lower lip reanimation is a safe, low morbidity procedure that enhances the psychological wellbeing of patients with facial palsy.

Lower Lip Reanimation: Experience Using the Anterior Belly of Digastric Muscle in 2-stage Procedure.

Retrospective analysis of 2-stage lower lip reanimations between 2010 and 2018 was performed. Demographics, etiology, and operative details were recorded. Videos were graded pre/postoperatively using a 5-point Likert scale by 21 independent observers. Objective changes of symmetry were analyzed using Photogrammetry (Emotrics). Twenty-seven patients were identified (median age 34.9 years, range 6-64). The mean duration between the 2 stages was 15.1 months. Follow-up ranged from 18-72 months. There were minor complications in 4 patients, and 1 case was abandoned due to insufficient length of anterior belly of digastric muscle. Average peer-reviewed scores improved from 2.1 to 3.2 (P < 0.05). Emotrics did not show improvement in static symmetry (P > 0.05). However, during open-lip smiling, lower lip height improved significantly (P < 0.05) whilst dental show improvements approached significance (P < 0.08). Lower lip symmetry was also improved during lower lip depression, as shown by improvements in lower lip height (P < 0.05), smile angle, and dental show (both P < 0.05). These results show the safety and efficacy of 2-stage lower lip reanimation using anterior belly of digastric muscle transposition. This procedure is our choice for longstanding lower lip paralysis and provides coordinated spontaneous lower lip depression, thus enhancing the overall perioral animation and smile.

Thin submental artery perforator flap for upper lip reconstruction: A case report

Reconstruction of upper lip defects can be challenging even for experienced surgeons. In order to restore both function and morphology, the use of quality soft tissue is essential. To this effect, the most common solution is the use of local flaps, or, in extreme situations, a free flap. However, a thin cutaneous upper lip defect may require a different approach. Perforator flaps are versatile and may allow an efficient reconstruction of soft tissue defects using adjacent similar tissues, providing the benefit of "like with like" coverage. We present the case of a 41-year-old female with a 1 × 1.5 cm basal cell carcinoma of the right-side upper lip, initially treated with a full thickness skin graft. Due to poor aesthetic and functional result, a thin submental artery perforator (SMAP) flap reconstruction was performed. Flaps' dimensions were 6 cm long and 4 cm wide and it was based on a perforator arising from the submental artery. Dissection was conducted above the platysma muscle, and the SMAP flap was transferred into the defect through a subcutaneous tunnel created below the mandible and posterior to the anterior belly of digastric muscle. The pedicle length of 6.5 cm was adequate for a tension free inset of the flap. Postoperative course was uneventful and the patient was discharged after 2 days. The 4-month follow-up showed a satisfying functional and aesthetic outcome with a concealed donor site scar. This report points out the coverage potential of the thin SMAP flap, which can be successfully used for a harmonious reconstruction in both color and texture of the upper lip.

Effects of Chewing Exerciser on the Recovery of Masticatory Function Recovery after Orthognathic Surgery: A Single-Center Randomized Clinical Trial, a Preliminary Study.

Background and Objectives: The aim of this study was to evaluate the effects of the chewing exerciser (CE) on the functional recovery of the masticatory muscles after orthognathic surgery. Material and Methods: This randomized clinical trial was conducted in patients undergoing bimaxillary orthognathic surgery including bilateral sagittal split ramus osteotomy. Postoperative physiotherapy (PT) was performed for 3 weeks starting 3 weeks after the surgery. The patients were randomly divided into two groups: control (Con) (conventional PT) group and CE group (use of CE in addition to conventional PT). The masticatory function was evaluated based on three standards: bite force (BF), amount of mouth opening (MO), and surface electromyography (sEMG) of the anterior temporal muscle (TA), masseter muscle (MM), sternocleidomastoid muscle, and anterior belly of digastric muscle before, 3 weeks (before PT) and 6 weeks after the surgery (after PT). Results: Finally, 22 subjects participated in this study: 10 patients for Con group and 12 patients for CE group. In both groups, the BF, which was reduced significantly after the surgery, recovered after the PT similar to that before the surgery. In both groups, the MO was also significantly reduced by the surgery. However, it did not recover as much, as it was before the surgery after applying the PT. There was no difference in BF and MO between the two groups. All muscles did not show significant changes in sEMG by surgery and PT at both resting and clenching states. Conclusion: Applying CE as a PT after orthognathic surgery did not cause any harmful side effects. In both groups, the weakened muscle activity after orthognathic surgery (OGS) was adequately restored 6 weeks after the surgery. However, CE did not offer a statistically significant benefit to the masticatory function in the recovery process after OGS.

Surgical anatomy of vascularized submental lymph node flap: Sharing arterial supply of lymph nodes with the skin and topographic relationship with anterior belly of digastric muscle.

Development of vascularized submental lymph node (VSLN) flap has encountered dilemmas; (a) whether to include skin paddle, (b) how to reduce the harvest area while gaining most lymph nodes. To answer, these structures were studied; submental perforator, lymph nodes in neck-level I and anterior belly of digastric muscle (ABDM). Forty VSLN flaps were harvested from 23 cadavers. The lymph nodes and arterial supply were studied macro- and microscopically. The nodes were classified by arterial supplies, location along the longitudinal axis and relationship with ABDM. VSLN flap had 4.4 lymph nodes by average (range 1-8) predominantly located in the posterior three-quarter of the flap. Half of the submental perforators were originated deep to ABDM. they circumvent the muscle, supplied much of the nodes in neck sublevel Ia before reaching the skin. While sublevel Ib located the most surgically accessible submental nodes. Most of their arterial supply was branched from submental perforator lateral to ABDM, not directly from the submental artery. The flap could be reduced to the posterior three-quarter of the original area. Skin paddle should be included to serve as an indirect lymph node monitor. If Ia lymph nodes are to be included, ABDM should be sacrified.

MUSCULAR ABNORMALITIES IN SUBMENTAL TRIANGLE – VARIATIONS OF ANTERIOR BELLY OF DIGASTRIC MUSCLE

The aim of this study is to highlight some unusual morphology of the digastric muscle anterior belly. During dissection of the bodies used in the practical lessons for second year medical students we found abnormal pattern of the suprahyoid region in the necks of two adult male cadavers. Both were with variable anterior bellies of digastric muscles. Case 1 presented a unilateral left variation, with an anomalous anterior belly. Case 2 presented bilateral variation, with the presence of two supernumerary bellies. Though multiplicity of anterior belly is common we provide interesting variations with anatomical and clinical importance. The different variants of the anterior belly of the digastric muscle can be found during the routine dissection or surgical procedure or imaging techniques. Anatomical variations of the anterior bellies of the digastric muscles can be easily confused with pathological conditions in CT and MR imaging. It is necessary to recognize that variants of the digastric muscle may happen in order to escape confusion when diagnosing abnormal lesions of the floor of the mouth and submental region.

The management of submental flap in the reconstruction of the oral cavity and skin of face defects

One of the most current problems in surgical treatment of the head and neck malignant neoplasms is the necessity for plastic replacement of defects that occur after tumor removal. The management of a submental flap in 34 patients with squamous cell cancer of the oral cavity and skin cancer of the face has been analyzed. There were 29 males and 5 females. The average age of patients was 56.9±5.23 years. The squamous cell cancer of the tongue was diagnosed in 18 patients, the floor of mouth — 7, the mucous of the cheek — 5, the retromolar triangle — 1 and skin basaloma of face in 3 patients. Single-stage reconstruction of postoperative defects after removal of the primary tumor was carried out simultaneously with the neck dissection. The submental flap with orthograde blood supply was used for reconstruction of the oral cavity defects in 31 patients and submental flap with the retrograde variant of blood supply was used to replace skin defects of face in 3 patients. The flap, which included skin, subcutaneous fat and the anterior belly of digastric muscle was used in 25 patients. A submental flap that included skin, subcutaneous fat, anterior belly of digastric muscle, and the fragment of the mylohyoid muscle was used in 9 patients. Total flap failure was observed in 2 patients and partial flap failure was observed in 3 patients. To replace the defect the supraclavicular artery skin and fascial flap were used in patients with total flap failure. Completion of primary plastics was 94%. Salivary fistula was observed in 2 patients and orostoma was not observed. Oral nutrition was restored for all 33 patients with oral cancer after surgery on 7–8 day. The hematoma in the donor’s site was diagnosed in 1 patient and partial sutures failure was observed in 4 patients. The obtained results allow us to recommend the submental flap as an effective way to reconstruct the defects of the oral cavity and the skin of the face after the removal of malignant tumors.

Anomalies of Anterior Belly of Digastric Muscle in Cadavers from South India

Anomalies of Anterior Belly of Digastric Muscle in Cadavers from South India

A morphological variant of anterior belly of digastric muscle: a cadaveric case report

Occurrence of accessory bellies of anterior belly of digastric muscle (ABD) in the submental region is not uncommon. However reporting of different pattern of accessory bellies is of tremendous clinical significance for head and neck surgeons, radiologists and plastic surgeons. Herein we report a rare asymmetrical variant of ABD in the suprahyoid region. Accessory bellies were observed on either side of midline. On the right side accessory belly had two segments; one segment extended between the lower part of the ABD and hyoid bone, other one extended between the digastric fossa of mandible to the body of hyoid bone. On the left side accessory belly extended between mylohyoid muscle and to the lower part of the ABD.Bangladesh Journal of Medical Science Vol.16(3) 2017 p.461-463

Anatomical Study and Variation of the Anterior Belly of Digastric Muscle: Case Report

Anatomical Study and Variation of the Anterior Belly of Digastric Muscle: Case Report

A study of variations of anterior belly of digastric muscle

Abstract Aim : To study the anatomical variations of anterior belly of digastric muscle. Materials &amp; Methods: In the present study, 30 human cadavers from the Department of Anatomy, Belagavi Institute of Medical Sciences, Belagavi were examined for the variations of anterior belly of digastric muscle during routine dissections of undergraduate and postgraduate students. The variations found were neatly dissected and photographs taken wherever necessary. Result: Out of 30 cadavers dissected3 specimens presented with variations. Discussion: First variation found had a unilateral accessory belly of digastric muscle on right side. Second variation was unilateral accessory belly of digastric muscle on left side and the third variation was bilateral accessory slips of digastric muscles. The details of these variations will be dealt in the article. Conclusion: As the variations of anterior belly of digastric muscle are common, the radiologists and the surgeons have to watch out for these while dealing with Sub mandibular region.

Clinical Implications of Accessory Anterior Belly of Digastric Muscle: A Case Study

Clinical Implications of Accessory Anterior Belly of Digastric Muscle: A Case Study

Botulinum Toxin Therapy versus Anterior Belly of Digastric Transfer in the Management of Marginal Mandibular Branch of the Facial Nerve Palsy: A Patient Satisfaction Survey.

BackgroundBotulinum toxin (BT) chemodenervation and anterior belly of digastric muscle (ABD) transfer are both treatment options in the management of an isolated marginal mandibular branch of the facial nerve (MMB) palsy. We compare the patient satisfaction following either BT injections or ABD transfer in the management of their isolated MMB palsy.MethodsPatients in the ABD-arm of the study were identified retrospectively from September 2007 to July 2014. The patients in the BT-arm of the study were identified prospectively from those attending the clinic. Both groups of patients completed a validated patient satisfaction survey. Statistical analysis was performed and a P-value <0.05 was considered statistically significant.ResultsSeven patients were in the ABD-arm and 11 patients in the BT-arm of the study. The patient satisfaction in both groups was high with 45% of ABD-arm patients and 40% of BT-arm patients rating their overall outcome as 'better' or 'much better', which was significantly more than the proportion rating their outcome as 'worse' or 'much worse' (P<0.001), although there was a significant trend towards those in the ABD-arm being more likely to be dissatisfied with their outcome (P=0.01).ConclusionsBT therapy is a good first-line intervention in the management of isolated MMB palsy. We have, however, shown that the overall satisfaction in both groups is high. Therefore, in patients who would prefer a more permanent solution to manage their facial asymmetry, ABD transfer remains a satisfactory treatment option with a good level of patient satisfaction.