Topography of the location of mental foramen in dried edentulous human mandible and its clinical implication

The mental foramen is an oval or round opening on external surface of mandible and transmits mental nerve and vessels. Mostly located at apex of second mandibular premolar or between the apices of premolars. The study was commenced on 60 dried edentulous mandibles with the aim to determine location of mental foramen(MF) with reference to surrounding anatomical landmarks. By measuring its distance from midline (symphysis menti), posterior border of ramus of mandible, lower border of mandible. Length of lower border (Base) of mandible was also measured. In present study most common shape of mental foramen was round (70%). The mean distances of MF from midline are 24.36mm on right side and 24.15mm left side. From posterior border of ramus are 64.45mm on right side and 64.15mm on left side. From base of mandible are 12.29mm on right side and 12.48mm on left side. Length of base mandible (midline to angle of mandible) is 83.27mm right side and 83.12mm left side. Ratio of distance from symphysis menti to MF and length of base of mandible are same on both sides that are 0.29. There is statistically significant positive correlation between distance from symphysis menti to MF and length of base of mandible.The MF plays a very important role in treatment planning and its location needs to be considered prior to placement of dental-implants, regional anesthesia, osteotomy-surgeries and during complete denture-fabrication in order to avoid MN injury and related complications.

Ideal Anatomical Landmark Points for Thoracic Esophagus Segmentation in the Chinese Population

Introduction: The standards of esophagus segmentation remain different between the Japan Esophageal Society (JES) guideline and the Union for International Cancer Control (UICC)/American Joint Committee on Cancer (AJCC) guideline. This study aimed to present variations in the location of intrathoracic esophageal adjacent anatomical landmarks (EAALs) and determine an appropriate method for segmenting the thoracic esophagus based on the relatively fixed EAALs.Patients and Methods: The distances from the upper incisors to the upper border of the esophageal hiatus, lower border of the inferior pulmonary vein (LPV), tracheal bifurcation, lower border of the azygous vein (LAV), and thoracic inlet were measured in the patients undergoing thoracic surgery. The median distances between the EAALs and the specified starting points, as well as reference value ranges and ratios, were obtained. The variation coefficients of distances and ratios from certain starting points to different EAALs were calculated and compared to determine the relatively fixed landmarks.Results: This study included 305 patients. The average distance from the upper incisors to the upper border of the cardia, the midpoint between the tracheal bifurcation and esophageal hiatus (MTBEH), LPV, LAV, tracheal bifurcation, and thoracic inlet were 41.6, 35.3, 34.8, 29.4, 29.5, and 20.3 cm, respectively. The distances from the upper incisors or thoracic inlet to any intrathoracic EAALs in men were higher than in women. In addition, the height, weight, and body mass index (BMI) were correlated with the distances. The ratio of the distance between the upper incisors and tracheal bifurcation to the distance between the upper incisors and upper border of the cardia and the ratio of the distance between the thoracic inlet and tracheal bifurcation to the distance between the thoracic inlet and upper border of the cardia possessed relatively smaller coefficients of variation.Conclusion: The distances from the EAALs to the upper incisors vary with height, weight, BMI, and gender. Compared with distance, the ratios are more suitable for esophagus segmentation. Tracheal bifurcation and MTBEH are ideal EAALs for thoracic esophagus segmentation, and this is consistent with the JES guideline recommendation.

Is Perpendicular Double Two-Hole Plates Fixation Superior to Single Four-Hole Plate Fixation to Treat Mandibular Symphysis Fracture?—A Finite Element Study

The effectiveness of a single four-hole plate (S4HP), perpendicularly oriented four-hole and two-hole plate (Per4H2HP), and perpendicularly oriented double two-hole plate (PerD2HP) for the fixation of a mandibular fracture was studied. A finite element analysis of the mandibular symphysis fractures treated with S4HP, Per4H2HP, and PerD2HP was performed. All surface nodes were fixed in the mandibular condyle region and occlusal muscle forces were applied. The maximal von Mises stress (MaxVMS) values of the plates, screws and screw holes were investigated. The displacement of the fracture site on the lower border of the mandibular symphysis was recorded. The displacement on the lower border of the fracture sites in the S4HP group was greater than that in the Per4H2HP group and the PerD2HP group. There was no eversion at the fracture site among all groups. Both the S4HP and Per4H2HP groups showed stress concentrations on the screws close to the fracture site. The MaxVMS increased when the number of screw holes on the mandibular anterior lower border decreased. The displacement of the fracture site and eversion with Per4H2HP and PerD2HP were far lower than those with S4HP. PerD2HP is a stable and green fixation technique for mandibular symphysis fractures.

Withdrawals lower India-China border tensions slightly

Headline INDIA/CHINA: Withdrawals lower border tension slightly

Position of posterior superior alveolar artery in relation to the maxillary sinus using cone beam computed tomography in Indian sub-population

Purpose: To assess the location of posterior superior alveolar artery (PSAA) using CBCT in relevance to sinus lift procedure for implant placement. Patients and Methods: A retrospective study was conducted using the CBCT data of 500 patients (n = 500). Linear measurements were carried out to localize the medio-lateral and vertical position of posterior superior alveolar artery in postero-lateral wall of maxillary sinus and its proximity to the floor of maxillary sinus using CS 3D imaging 3.7.0 software program. The relative position of PSAA was determined as; (a) intra-osseous, (b) below the membrane and (c) outer-cortex of lateral sinus wall. The location of PSAA was assessed in molar region bilaterally by using following radiographic measurement; (1) distance between the lower border of posterior superior alveolar artery and alveolar crest, (2) height from the floor of maxillary sinus to alveolar crest and (3) distance from the posterior superior alveolar artery to medial wall of maxillary sinus. Results: The prevalence of the artery was observed in 99.4% of the sinuses and was mostly intraosseous (84.2%).The mean distance between the lower border of the artery and alveolar crest is significantly higher in males compared to females (P < 0.01). The distribution of artery location did not differ significantly across various age groups (P > 0.05). Discussion/Conclusion: The most common variant of PSAA was identified in the intra-osseous region and the mean distance of the vessel to crest of the residual ridge differs significantly with gender and not with age.

Is it possible to determine the place of rupture during an ectopic pregnancy?

In the hospital of St. Roha was taken unconscious, a 24-year-old worker in a factory, pale, with a haggard face. Heart sounds are clear, the lower border of the lungs is moved upward by 1 rib. The abdomen is tense, increased in volume. Tissue tension is especially pronounced in the right iliac cavity. At the lightest palpation of the abdomen, the patient's anxiety increases, and she attracts her left leg to the body; the right leg is motionless. With percussion of the abdomen, the tone is timpanic, with the exception of the right iliac cavity, where it is significantly dull.

About of the Necessary of Corrections of the NRB-99/2009 and OSPORB-99/2010

Purpose: The Basic Sanitary Rules (OSPORB-99/2010) and the Standards of Radiation Safety (NRB-99/2009) contain requirements on the treatment of radionuclide contaminated materials and waste, but non-radioactive substances and radioactive waste. The aim of this work is to develop recommendations for adjustment of OSPORB-99/2010 and NRB-99/2009 for radiation safety of current and future generations of people. Results: Identified and justified by the shortcomings of NRB-99/2009 and OSPORB-99/2010 governing the treatment of materials and waste contaminated by radionuclides, but non-radioactive substances and radioactive waste, which can lead to overexposure of present and future generations of people. Developed and justified proposals for adjustments to NRB-99/2009 and OSPORB-99/2010. Conclusions: It was proposed adjustment of NRB-99/2009 and OSPORB-99-2010: in NRB-99/2009 it was proposed to delete from paragraph 5.3.4 the provisions regulating the use of materials for road construction; in OSPORB-99/2010 the return to OSPORB-99 on establishment of the lower border of wastes and materials of limited use on total alpha and beta-activity is offered.

Computer-aided diagnosis system for osteoporosis based on quantitative evaluation of mandibular lower border porosity using panoramic radiographs

Objectives: A new computer-aided screening system for osteoporosis using panoramic radiographs was developed. The conventional system could detect porotic changes within the lower border of the mandible, but its severity could not be evaluated. Our aim was to enable the system to measure severity by implementing a linear bone resorption severity index (BRSI) based on the cortical bone shape. Methods: The participants were 68 females (>50 years) who underwent panoramic radiography and lumbar spine bone density measurements. The new system was designed to extract the lower border of the mandible as region of interests and convert them into morphological skeleton line images. The total perimeter length of the skeleton lines was defined as the BRSI. 40 images were visually evaluated for the presence of cortical bone porosity. The correlation between visual evaluation and BRSI of the participants, and the optimal threshold value of BRSI for new system were investigated through a receiver operator characteristic analysis. The diagnostic performance of the new system was evaluated by comparing the results from new system and lumbar bone density tests using 28 participants. Results: BRSI and lumbar bone density showed a strong negative correlation (p < 0.01). BRSI showed a strong correlation with visual evaluation. The new system showed high diagnostic efficacy with sensitivity of 90.9%, specificity of 64.7%, and accuracy of 75.0%. Conclusions: The new screening system is able to quantitatively evaluate mandibular cortical porosity. This allows for preventive screening for osteoporosis thereby enhancing clinical prospects.