If G is a connected graph, then HA(G) = ∑ u6=v(deg(u) + deg(v))/d(u, v) is the additively Harary index and HM (G) = ∑ u6=v deg(u) deg(v)/d(u, v) the multiplicatively Harary index of G. G is an apex tree if it contains a vertex x such that G − x is a tree and is a k-apex tree if k is the smallest integer for which there exists a k-set X ⊆ V (G) such that G − X is a tree. Upper and lower bounds o...

Introduction: The exact measurement of the root canal length is of great importance in root canal therapy. Although, determination of the root canal length through radiography is the most common method, recently electronic apex locators are being used to determine working length and decrease the number of radiographs. The purpose of this study was to compare the accuracy of an electronic apex l...

Field Ion Microscopy (FIM) and Scanning Tunneling Microscopy (STM) have found a wide application in nanotechnology. These microscopes use a metallic nanotip for image acquisition. Resolution of FIM and STM images depends largely on the radius of nanotip apex; the smaller the radius the higher the resolution. In this research, for tungsten nanotip fabrication, electrochemical etching of tungsten...

This study investigates how tissue Doppler imaging (TDI) and speckle tracking echocardiography (STE) describe regional myocardial deformation during controlled reductions of left anterior descending (LAD) coronary artery perfusion pressure. In eight anesthetized pigs, a shunt with constrictor was installed from the brachiocephalic artery to the LAD. Data were obtained with open shunt, followed ...

during endodontic treatment, clinicians may face endodontic procedural mishaps such as broken instruments, which is a complex situation especially when the file breaks beyond the apex. this condition is associated with potential risk of contamination, which compromises the healing process. management of a broken instrument beyond the apex is difficult and time consuming and requires creativity ...

The conventional method of apexification with calcium hydroxide has certain disadvantages such as very long period of treatment, tooth fracture and an incomplete calcification of the bridge. Mineral trioxide aggregate (MTA) as an apical sealing material has gained importance as an alternative treatment for open apices. We report a case of complete healing of a periapical abscess after placement...

Introduction: Knowledge of the internal anatomy of the tooth, apical foramen (AF) and mental foramen (MF) is considered a basic prerequisite before root canal surgical and non-surgical treatments. The aim this study is evaluation the distance and situation of AF & MF to anatomic apex of mandibular  premolar. Materials & Methods: In this cross-sectional study, CBCT images of mandibular p...