Inferior border of Mandible

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Evaluation of Lingual Fracture pattern on the Mandible after Bilateral Sagittal Split Osteotomy With and Without Inferior Border Osteotomy

Evaluation of Lingual Fracture pattern on the Mandible after Bilateral Sagittal Split Osteotomy With and Without Inferior Border Osteotomy

Along with the decreased force required to split the bone, adding an osteotomy at the lower border of the mandible also improved the ability to control the splitting process. Although, the outcomes of our study have been found to be significant and favorable, application of the modified technique must be done careful as it may be technique sensitive. It is also necessary to consider the bio-mechanical characteristics of dry cadaveric human mandible would be different from that of alive human mandible. To further recommend the use of the technique in clinical operative conditions, it may be relevant to consider using instrument that could easily facilitate a safe method to make an inferior border osteotomy via intra-oral approach. A notable suggestion would be the use of piezoelectric equipment with a hooked oscillating saw to facilitate an inferior border osteotomy. A rotating or oscillating saw could be used. Wolford and Davis 50 developed areciprocating saw to cut the inferior border of the mandible in 1990. Using this they achieved mandible splitting without malleting. They described a more predictable split with fewer complications. The marginal branch of the facial nerve should be considered while attempting the technique in patients. According to the authors, this technique should only be used by experienced surgeons to avoid complications.

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Gaining surgical access for repositioning the inferior alveolar neurovascular bundle

Gaining surgical access for repositioning the inferior alveolar neurovascular bundle

This study is aimed at determining anatomical landmarks that can be used to gain access to the inferior alveolar neurovascular (IAN) bundle. Scanned CBCT (i-CAT machine) data of sixty patients and reconstructions performed using the SimPlant dental implant software were reviewed. Outcome variables were the linear distances of the mandibular canal to the inferior border and the buccal cortex of the mandible, measured immediately at the mental foramen (D1) and at 10, 20, 30, and 40 mm (D2–D5) distal to it. Predictor variables were age, ethnicity, and gender of subjects. Apicobasal assessment of the canal reveals that it is curving downward towards the inferior mandibular border until 20 mm (D3) distal to the mental foramen where it then curves upwards, making an elliptic-arc curve. The mandibular canal also forms a buccolingually oriented elliptic arc in relation to the buccal cortex. Variations due to age, ethnicity, and gender were evident and this study provides an accurate anatomic zone for gaining surgical access to the IAN bundle. The findings indicate that the buccal cortex-IAN distance was greatest at D3. Therefore, sites between D2 and D5 can be used as favorable landmarks to access the IAN bundle with the least complications to the patient.

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Fractures of the Mandible: An Urban Centre Study

Fractures of the Mandible: An Urban Centre Study

provide better visualization and access to the inferior border, but the marginal mandibular nerve may be placed at risk. Most plating companies offer specialized cheek retractors that aid in the intraoral approach to the posterior mandible. The fracture site should be adequately debrided of all fibrin and hematoma to allow tight approximation of the bone edges. Reduction can often be achieved with application of intermaxillary fixation. Additional reduction may be achieved with the use of a lower border wiring technique or bone pliers to approximate two fracture fragments. This lower border wire can then be removed once a plate has been placed across the fracture line. There continues to be debate over whether to maintain intermaxillary fixation after open reduction and internal fixation of the mandible.

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Comparison of superior border and inferior border fixation for displaced mandibular angle fractures

Comparison of superior border and inferior border fixation for displaced mandibular angle fractures

Mandibular fractures that shorten the vertical height of the ramus by their displacement (i.e., condylar fractures in patients without posterior teeth or those not placed intomaxillomandibular fixation) will cause the angle of the mandible to be more superior than it would be following reduction and fixation. Therefore, the incision should be 1.5 to 2 cm inferior to the anticipated location of the inferior border. The incision is located along a suitable skin crease in whatever anteroposterior position needed for mandibular exposure. For a fracture that extends toward the gonial angle, the incision should begin behind and above the gonial angle, extending downward and forward until it is in front of the gonial angle. For fractures located more anterior than the gonial angle, the incision does not have to extend behind and/or above the gonial angle, but may extend farther anteriorly.

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Preserving the marginal mandibular branch of the facial nerve during submandibular region surgery: a cadaveric safety study

Preserving the marginal mandibular branch of the facial nerve during submandibular region surgery: a cadaveric safety study

The course of the marginal mandibular nerve is subjected to a wide array of anatomical variations in the subman- dibular region. Surgical anatomy of this nerve might vary among different populations. Appreciation of these varia- tions is important to reduce morbidity following surgeries involving submandibular region. Different from earlier re- ports, we found at least one ramus of each MMBFN lo- cated caudal to the inferior border of the body of the mandible. MMBFN is at highest risk of being damaged when a skin incision is placed 6.09 to 7.65 mm from the inferior angle of mandible.

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A Comparative Radiographic evaluation of occlusal plane in dentulous and edentulous subjects: A Clinical study

A Comparative Radiographic evaluation of occlusal plane in dentulous and edentulous subjects: A Clinical study

The present study had its own limitations and there is always a scope for future enhancement. In some instances the mental foramen is not distinctly visible on the panoramic radiographs. Various reasons have been sited for its conspicuous absence in the literature; some amongst them include superimposition of tooth buds in mixed dentition radiographs, inability to distinguish from the trabecular pattern in complete dentition radiographs, thin mandibular bone in edentulous radiographs, and overly dark radiographs. 69 Recent studies have questioned the constancy of the mental foramen and the inferior border of the mandible with increasing duration of edentulism but nothing conclusive has yet been put forward on this aspect. Additional studies are needed to validate this fact and draw more convincing conclusions.

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An improved technical trick for identification of the thoracodorsal nerve during axillary clearance surgery: a cadaveric dissection study

An improved technical trick for identification of the thoracodorsal nerve during axillary clearance surgery: a cadaveric dissection study

All the cadavers had bilateral single axillary veins. The LTV was present in all the specimens. All the LTVs passed lateral to the lateral border of pectoralis minor except in one specimen, where the LTV passed along the lateral border of pectoralis minor. The TDN was consistently present posterolateral to the LTV. The accessory LTVs were found in bilateral axillae of two dis- sected cadavers (n = 2, 20%). The accessory LTVs were much smaller in diameter when compared to the princi- pal LTVs so as to not cause any confusion in recognizing the main LTV. The accessory veins were seen proximal to the junction of the main trunk of the LTV with the axillary vein in all specimens. They had no communica- tions with each other and drained independently to the axillary vein. Three of the accessory LTVs were medial to the lateral border of pectoralis minor and one was lat- eral. The mean distance between the proximal accessory LTVs and the lateral border of pectoralis minor was 15 mm (±4 mm). The distal one was situated 47 mm distal to the lateral border of pectoralis minor.

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New parameters describing morphological variations in the suprascapular notch region as potential predictors of suprascapular nerve entrapment

New parameters describing morphological variations in the suprascapular notch region as potential predictors of suprascapular nerve entrapment

The proposed parameters have some limitations. Contrary to the ARC, calculation of the AOC does not require tools for area evaluation but only measurement of curves along the border of the SSN. However, this parameter does not take into account the curved inferior (STSL) or superior (ACSL) borders of the ligaments. Thus, AOC measurement can overestimate the predicted risk in ligaments with dis- tinctly curved borders. On the other hand, the SSN ambit below the ACSL is not included in the formula, which may cause the risk to be underestimated.

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The neuronal structure of the inferior colliculus in the bank vole (Clethrionomys glareolus) - Golgi and Nissl studies

The neuronal structure of the inferior colliculus in the bank vole (Clethrionomys glareolus) - Golgi and Nissl studies

The inferior colliculus (IC) of the bank vole is a well-developed mesencephalic structure. The ros- tral part of IC is made up of a thin strip of cells that extends dorsally and borders gradually the superior colliculus, which is located between IC and the peri- aqueductal grey matter. Further caudally, the supe- rior colliculus becomes smaller, disappears and is completely replaced by IC. At this level IC takes an oval shape and becomes a heterogeneous structure, consisting of 3 nuclei: the external nucleus and the pericentral nucleus, which are located on the outer border of IC, and the central nucleus, which is the largest one. On the medial side of the central nucleus lies the periaqueductal grey matter, while on the ven- tral side lie the nucleus cuneiform and the dorsal nu- cleus of the lateral lemniscus. The ventral part of the central nucleus is composed of the largest neurons, which are loosely packed, whereas the dorsal part of this nucleus shows the laminated structure. This struc- ture was not noticeable on the Nissl material, but the tissue impregnated according to the Golgi method showed it distinctly. The caudal tip of IC has the shape of a small oval, which is bordered around by cerebel- lar tissue.

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Ranibizumab in the treatment of choroidal neovascularization on the border of an inferior staphyloma associated with tilted disc syndrome

Ranibizumab in the treatment of choroidal neovascularization on the border of an inferior staphyloma associated with tilted disc syndrome

Severe visual loss has been reported on eyes with tilted disc syndrome when the upper-temporal border of an inferior staphyloma lies across the macula. It has been hypothesized that the sharp curve on the border of the staphyloma causes mechanical or hemodynamic changes and promotes the development of macular complications. 2 Several published

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The Clinical Anatomy of Cricothyroid Membrane – Its relevance to Emergent Subglottic Procedures.

The Clinical Anatomy of Cricothyroid Membrane – Its relevance to Emergent Subglottic Procedures.

Dover et al (1996) in his landmark study of the dimensions and structures related to the membrane, found that in the subcutaneous tissue, paired anterior jugular veins crossed the membrane in a vertical direction in the majority of specimens. He also found numerous venous tributaries of the superior and inferior thyroid veins crossing the cricothyroid membrane in 80% of 15 dissections. Deep to the sternohyoid muscles, he found that small veins from the region of the thyroid isthmus traversed the cricothyroid membrane, followed the cricothyroid and superior thyroid arteries, and drained into the internal jugular vein. He also suggests that wound bleeding due to injury of the anterior jugular vein or anterior branch of the superior thyroid artery is possible following a horizontal skin incision.

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Clinical and Imaging Analysis of a Cerebellar Watershed Infarction

Clinical and Imaging Analysis of a Cerebellar Watershed Infarction

We performed imaging for the 178 admitted cases with a cerebral infarction. For certain patients with a smaller infarct size, the infarct area location was not within an artery that supplied blood to the cerebellum, but it was localized at the border between two arteries, which is indicative of a cerebellar watershed infarction. Cerebellar watershed infarctions can be divided into two types; one has wedge-shaped lesions that affect the cortex, and the other is located deep in the cerebellum. A cerebellar watershed infarction is rarely observed in clinical practice, and its incidence has not been reported. In our study, 24% of patients with a cerebellar infarction had watershed infarctions. However, because patients with a cerebellar watershed infarction have significantly less severe symptoms compared with other cerebellar infarction patients, certain cerebellar infarction patients might have died before a vascular examination. Therefore, the cerebellar watershed infarction incidence may be lower than this value.

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Osteosarcoma of Mandible

Osteosarcoma of Mandible

The serial axial section (Fig 3a) of CT showed extension of lesion into the adjacent soft tissue and ossifications with in the tissue on the buccal side and on the lingual side there was a breach in the periosteum and it resulted in elevation of periosteum and bone deposition between elevated periosteum and adjacent normal bone.The serial coronal sections (Fig 3b), showed the radioopacity within the marrow space of left mandible compared to that of right suggestive of osteoblastic proliferation.In 3D reconstruction images (Fig 3c), we found the new bone formation both on the buccal and lingual sides. The MRI(Fig 4a) sections showed the extent of soft tissue involvement both on the buccal and lingual sides. Anterior border of masseter on the buccal side and a portion of mylohyoid on the lingual side are involved.The coronal sections (Fig 4b) showed thebucco lingual extension. And this extension appears to be connected through the extraction socket.

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Formation of Condyle-Like Structure after Treatment of Temporomandibular Joint Ankylosis: Literature Review and Long-Term Follow-Up of Two Patients

Formation of Condyle-Like Structure after Treatment of Temporomandibular Joint Ankylosis: Literature Review and Long-Term Follow-Up of Two Patients

Attaining spontaneous healing and rapid bone regen- eration by functional treatment after condyle fractures in growing patients is a well known clinical condition [2, 25, 26]. On the other hand, spontaneous bone regeneration in growing patients and in adults after resection of the large proportions of the mandible has been rarely reported by max- illofacial surgeons. At the beginning, authors reported this phenomenon as “unusual rapid bone regeneration following mandibular resection” [27–32]. In the following years, some other studies followed, speculating on reasons of the new bone formation after partial removal of the mandible [33–37]. The purpose of the presented paper is to reveal the existence of an inherent capability of the mandible, rapid bone growth of the ramus mandible, and formation of a condyle-like process after resection of the ramus for the treatment of TMJ ankylosis in two patients.

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The safe screw path along inferior border of the arcuate line at acetabular area: an anatomical study based on CT scans

The safe screw path along inferior border of the arcuate line at acetabular area: an anatomical study based on CT scans

measurement methods were performed. With several points selected along the edge of acetabulum then expended by 5.0 mm, an arc was delineated to repre- sent the subchondral bone thickness. A line through the screw entry point and tangent to the inferior edge of the arc was defined as the screw-placement direc- tion. Formed by the tangent line and the normal plane, the angle was marked as θ. The distance, de- fined as the screw length d from the screw entry point to the intersection point, was measured in section 1 and 5. Due to the similar shaping, the measurements for section 2 and section 3 were repre- sented with the same model (Figs. 3 and 4).

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Normal radiological anatomy of thyroid cartilage in 600 Chinese individuals: implications for anterior cervical spine surgery

Normal radiological anatomy of thyroid cartilage in 600 Chinese individuals: implications for anterior cervical spine surgery

Preoperative positioning in anterior cervical approach surgery generally utilizes anatomical structures such as the angle of the mandible, hyoid bone, thyroid cartilage, cricoid cartilage, and carotid artery nodule [1, 6]. For ex- ample, approximately 70% of the mandibular angle is lo- cated at the interval between C2 and C3 [1], while the majority of cervical decompression surgeries are located below the C4 level [7]. Therefore, the angle of the man- dible is not suitable for the majority of positions in an- terior cervical approach surgery. The thyroid cartilage is closely associated with the cervical vertebra in terms of anatomy. It is located at the C4–C5 level, serves as a prominent anatomical landmark, and is therefore con- venient for pre-surgical positioning in the anterior cer- vical approach.

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Comparative study of lichtenstein’s hernia repair under local anaesthesia and spinal anaesthesia

Comparative study of lichtenstein’s hernia repair under local anaesthesia and spinal anaesthesia

In this repair several tissue layers are approximated , therefore the recurrence rate is less and the tesion is equally distributed.In this repair after the cord structures and sac are separated and sac ligated, the genital branch of genitofemoralnerve is divided and various layers are dissected carefully.Initially superior and inferior flap of transversalis fascia is raised above and below.

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Foramina of the anterior mandible in dentate and edentulous mandibles

Foramina of the anterior mandible in dentate and edentulous mandibles

Since placement of dental implants in the anterior mandible has been widely applied, the meticulous knowledge of the foramina topography and their content is of paramount importance for dentists and maxillofacial surgeons. In our research, the presence of at least one MLF indicates that the MLF is a con- stant structure, similarly to other studies [13, 18, 26]. A negative correlation between the MLF presence in the areas superior and medial to GT was found, indicating that usually a single foramen exists at the level of GT and above. This finding indicating that the most frequent location of the MLF was at the level of GT and above highlights the clinical significance of the MLF location during dental implants placement [13, 23, 26]. The LLF were detected in 78.4% of the mandibles (60.8% on the right and 72.2% on the left side) in our study. The LLF occurrence presents a wide range from 30% to 76% [4, 10, 13, 23] among several studies, due to the different methodology in their topography determination. In our study, the LLF were observed at the level of GT and below, similarly to Liang et al. [13] and Przystańska and Bruska [23].

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Comparative Study of Mandibular Morphology in Patients with Hypodivergent, Hyperdivergent and Average Growth Patterns: A Cephalometric Study

Comparative Study of Mandibular Morphology in Patients with Hypodivergent, Hyperdivergent and Average Growth Patterns: A Cephalometric Study

Posterior rotation of the condyles has been shown to dominate in individuals with the classic long face syndrome, and anterior inclination of the condylar head can be associated with counter clock-wise mandibular rotations. It was also reported that reduced condylar growth represents clock-wise rotators of mandible in relation to the cranial base. The proliferation of condylar cartilage and endochondral ossification of condyle occurs via complex biomechanical interactions. The magnitude, direction and duration of the resultant condylar growth may be influenced by genetic determinants as well as intrinsic and extrinsic control factors.

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High Resolution Imaging of an Ancient Egyptian Mummified Head: New Insights into the Mummification Process

High Resolution Imaging of an Ancient Egyptian Mummified Head: New Insights into the Mummification Process

It is more probable that the jaw was mobilized for some other purpose that took precedence over simply preserving the mummy’s appearance. Although this could have been done simply to gain deeper access to the oral cavity, it is more prob- able to have had some more important ritual significance. From the time of the pyramids until the last days of ancient Egyptian history, one of the most important parts of the fu- nerary ritual was the “Opening of the Mouth” ceremony. The possibility that what we have observed in the case of Djehu- tynakht was somehow related to this rite deserves consider- ation. The “Opening of the Mouth” ceremony would be diffi- cult to perform in the presence of rigor mortis; the facial mutilation described above would effectively overcome this problem by detaching the mandible from the muscles of mastication.

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