Relationship of maxillary and mandibular effective base length, arch length and dental crowding in different vertical growth pattern

Objectives: The objectives of the study were to assess, measure, and correlate the maxillary and mandibular effective base length, arch length to the amount of dental crowding in different vertical growth pattern patients. Materials and Methods: Sample comprising 100 pre-treatment lateral cephalograms and study models (age group – 16–25 years) was randomly selected. The sample was divided into two groups, that is, clockwise (50) and anticlockwise (50) rotation based on the measurement of the gonial angle. The gonial angle and maxillary and mandibular effective lengths were measured on pre-treatment lateral cephalograms. Dental crowding and arch length were measured on the pre-treatment dental casts. Intergroup comparisons of effective base length, arch length, and crowding were performed with unpaired t-tests. Correlations between effective base length, arch length, and dental crowding were examined by means of Pearson’s correlation coefficient (P < 0.05). Results: Subjects with clockwise rotation significantly had more mandibular dental crowding and significantly decreased mandibular arch length compared to the anticlockwise group. An inverse correlation was found between maxillary and mandibular effective base length, arch length, and dental crowding while a positive correlation was found between maxillary and mandibular base length and arch length in both the groups. Conclusion: Clockwise rotation of the mandible along with skeletal and dental factors such as decreased effective base lengths and arch length, respectively, constitutes an important factor leading to dental crowding.

Paleomagnetic Results from Western Anatolia: Evidence of Microblock Rotations after Emplacement of the Lower Miocene Yuntdağ Volcanic Rocks

The eastern Aegean region has undergone north dipping subduction in the Oligocene, continental collision and then Miocene-Pliocene extension, which is associated with widespread Miocene volcanism. The aim of this study is to assess the possibility of block rotations due to stress variations in the Dikili (İzmir) province, Western Anatolia, based on paleomagnetic data obtained from 35 independent sites in addition to results from 19 sites in earlier studies. The lower Miocene Yuntdağ volcanic rocks were emplaced in three different structural blocks, the Dikili, Zeytindağ and Bergama blocks. Clockwise rotation is found in the Dikili and Zeytindağ blocks that varies from R (± DR) = 12.5° (± 7.4°) in the west to R (± DR) = 35.6°± (13.2°) in the east, respectively. In contrast, a counterclockwise rotation of R (± DR) =-38.1° (± 6.4°) resulted in the Bergama block, in the north of the Dikili and Zeytindağ blocks. A scissor-like basin evolution is suggested during the opening of the Bakırçay graben which led to counterclockwise rotation of the Bergama block and clockwise rotation of the Dikili and Zeytindağ blocks after lower Miocene to present. The rotation pattern derived from results of this study demonstrates that localized small scale deformation due to basin evolution besides regional affects must be considered as part of the deformation matrix in this area.

Video-assisted thoracoscopic parenchymal sparing “rotational” bronchoplasty for managing bronchial carcinoid tumor

We present a modified bronchoplasty technique involving rotation of the bronchial structures. Our goal was to reconstruct the bronchus without using any foreign material while fully preserving the parenchyma. We used a biportal VATS approach. The centrally located bronchial tumor at the juncture between the right main bronchus, the right upper lobe bronchus, and the bronchus intermedius was first resected. The right upper lobe bronchus was rotated caudally, toward the bronchus intermedius, together with a slight clockwise rotation posteriorly to facilitate the approximation and tension-free closure of the bronchial defect. This video tutorial demonstrates the operative steps and explains how the rotational aspect is achieved.

Paleomagnetic Rotation Study of Woodlark-Australia plate motions in the Woodlark Rift, SE Papua New Guinea

<p>The Woodlark Rift in SE Papua New Guinea is a continental rift to the west of active oceanic spreading in the Woodlark Basin, which separates the Australian Plate to the south from the relatively anticlockwise rotating Woodlark Plate to the north. During Pliocene to Recent times the Woodlark Rift has been the setting for rapid exhumation of the world’s youngest UHP rocks (Baldwin et al., 2004, 2008; Gordon et al, 2012; Little et al., 2011), and is currently one of few places on the globe where active continental breakup is occurring ahead of a propagating oceanic spreading centre. While the Woodlark Basin contains a record of oceanic spreading since ˜6 Ma (Taylor et al., 1999), and GPS data describe present-day crustal motions (Wallace et al., manuscript in review), the Neogene temporal and kinematic evolution of continental extension in the Woodlark Rift is less well constrained. We compare Characteristic magnetization directions for six formations, Early Miocene (˜20 Ma) to Late Pliocene (3 ± 0.5), with contemporaneous expected field directions corresponding to Australian Plate paleomagnetic pole locations. We interpret declination anomalies (at 95% confidence) to estimate finite vertical-axis rotations of crustal blocks with respect to a fixed Australian Plate. Temporal and spatial relationships between declination anomalies for six formation mean directions, across four paleomagnetic localities, provide new evidence to constrain aspects of the Miocene to Recent history of the Woodlark Rift. We obtained 250 oriented core samples from Miocene to Pliocene aged rocks at four localities in the Woodlark Rift. Components of Characteristic Remanent Magnetization (ChRM) have been determined from step-wise thermal and alternating field demagnetization profiles of >300 individual specimens. A total of 157 ChRM components contribute to the calculation of representative paleomagnetic directions for six formations, which have undergone vertical-axis rotations with respect to the Australian Plate associated with development of the Woodlark Rift. Pliocene volcanic rocks at two key localities near the northern extent of the rift record that: 1) The Amphlett Islands has experienced 10.1 ± 7.6° of anticlockwise rotation since 3 ± 0.5 Ma; 2) NW Normanby Island has undergone a 16.3 ± 9.5° clockwise rotation during the same time interval. Sedimentary rocks at Cape Vogel Peninsula on the northern coast of the mainland Papuan Peninsula, record variable anticlockwise finite rotations of 28.4 ± 10.9° and 12.4 ± 5.5° for Early and Middle Miocene rocks respectively, in contrast to a younger clockwise rotation of 6.5 ± 11.2° for Late Miocene rocks. At the Suau Coast locality, on the south eastern coast of the Papuan Peninsula, Late Miocene dikes record 22.7 ± 13.3° of anticlockwise rotation. At the Amphlett Islands and NW Normanby localities paleomagnetic data are consistent with current GPS plate motions, suggesting the current kinematics in the rift were established by at least ˜3 Ma. The Amphlett Islands result is consistent with the rate of Pliocene sea floor spreading in the Woodlark Basin, suggesting that locality can be considered as fully on the Woodlark Plate. The clockwise rotation indicated at NW Normanby Island may record development of an incipient dextral transfer fault within an active part of the Woodlark Rift. Time-varying declination anomalies from the Cape Vogel Peninsula suggest that rifting began there by ˜15 Ma, 7 Ma earlier than previously inferred based on stratigraphic evidence. Furthermore, paleomagnetic data from the south coast of the Papuan Peninsula suggests that early rifting extended further south, and has since contracted to where continental extension is currently accommodated north of the Papuan Peninsula.</p>

Paleomagnetic Rotation Study of Woodlark-Australia plate motions in the Woodlark Rift, SE Papua New Guinea

<p>The Woodlark Rift in SE Papua New Guinea is a continental rift to the west of active oceanic spreading in the Woodlark Basin, which separates the Australian Plate to the south from the relatively anticlockwise rotating Woodlark Plate to the north. During Pliocene to Recent times the Woodlark Rift has been the setting for rapid exhumation of the world’s youngest UHP rocks (Baldwin et al., 2004, 2008; Gordon et al, 2012; Little et al., 2011), and is currently one of few places on the globe where active continental breakup is occurring ahead of a propagating oceanic spreading centre. While the Woodlark Basin contains a record of oceanic spreading since ˜6 Ma (Taylor et al., 1999), and GPS data describe present-day crustal motions (Wallace et al., manuscript in review), the Neogene temporal and kinematic evolution of continental extension in the Woodlark Rift is less well constrained. We compare Characteristic magnetization directions for six formations, Early Miocene (˜20 Ma) to Late Pliocene (3 ± 0.5), with contemporaneous expected field directions corresponding to Australian Plate paleomagnetic pole locations. We interpret declination anomalies (at 95% confidence) to estimate finite vertical-axis rotations of crustal blocks with respect to a fixed Australian Plate. Temporal and spatial relationships between declination anomalies for six formation mean directions, across four paleomagnetic localities, provide new evidence to constrain aspects of the Miocene to Recent history of the Woodlark Rift. We obtained 250 oriented core samples from Miocene to Pliocene aged rocks at four localities in the Woodlark Rift. Components of Characteristic Remanent Magnetization (ChRM) have been determined from step-wise thermal and alternating field demagnetization profiles of >300 individual specimens. A total of 157 ChRM components contribute to the calculation of representative paleomagnetic directions for six formations, which have undergone vertical-axis rotations with respect to the Australian Plate associated with development of the Woodlark Rift. Pliocene volcanic rocks at two key localities near the northern extent of the rift record that: 1) The Amphlett Islands has experienced 10.1 ± 7.6° of anticlockwise rotation since 3 ± 0.5 Ma; 2) NW Normanby Island has undergone a 16.3 ± 9.5° clockwise rotation during the same time interval. Sedimentary rocks at Cape Vogel Peninsula on the northern coast of the mainland Papuan Peninsula, record variable anticlockwise finite rotations of 28.4 ± 10.9° and 12.4 ± 5.5° for Early and Middle Miocene rocks respectively, in contrast to a younger clockwise rotation of 6.5 ± 11.2° for Late Miocene rocks. At the Suau Coast locality, on the south eastern coast of the Papuan Peninsula, Late Miocene dikes record 22.7 ± 13.3° of anticlockwise rotation. At the Amphlett Islands and NW Normanby localities paleomagnetic data are consistent with current GPS plate motions, suggesting the current kinematics in the rift were established by at least ˜3 Ma. The Amphlett Islands result is consistent with the rate of Pliocene sea floor spreading in the Woodlark Basin, suggesting that locality can be considered as fully on the Woodlark Plate. The clockwise rotation indicated at NW Normanby Island may record development of an incipient dextral transfer fault within an active part of the Woodlark Rift. Time-varying declination anomalies from the Cape Vogel Peninsula suggest that rifting began there by ˜15 Ma, 7 Ma earlier than previously inferred based on stratigraphic evidence. Furthermore, paleomagnetic data from the south coast of the Papuan Peninsula suggests that early rifting extended further south, and has since contracted to where continental extension is currently accommodated north of the Papuan Peninsula.</p>

Neotectonics, Kinematics, and Evolution of the Vernon, Awatere, and Cloudy Faults of the Marlborough Fault System, New Zealand

<p>The coastal Awatere, Vernon, and Cloudy faults are bent and mutually intersecting, forming a complexly deforming dextral-oblique fault network. To try to explain the kinematic, paleoseismic and evolutionary complexities of this network, I present the results of an investigation into the rates, timing, and direction of slip on the faults within the network; which bifurcate eastwards from the central Awatere fault at the northeast end of the Marlborough Fault System. Displacements of dated and nondated late Quaternary features by the three faults were measured both onshore and offshore, constraining the kinematics of the fault network. The Vernon fault oddly maintains a dextral-reverse structure although it varies over 90° in strike and the Cloudy and coastal Awatere faults change from nearly pure strike slip to having a normal component eastwards. These data indicate that the fault-bounded blocks between the coastal Awatere, Vernon and Cloudy faults are rotating anticlockwise about a vertical axis relative to the block to the north of the fault system. Slip-rate data also indicate that of the 6 ± 1 mm/yr of slip on the central Awatere Fault, 1.1 ± 0.6 mm/yr has been partitioned ENE onto the coastal Awatere Fault and <4.9 mm/yr has been partitioned NNE onto the Vernon Fault. A slip-rate shortage in the splays of the Vernon Fault in the Vernon Hills is caused by a combination of unsighted faults and rotation of smaller splay-bounded blocks within the Vernon Hills. Paleoseismic records on the Vernon Fault were analysed onshore in a trench and offshore on seismic lines, with the records in good agreement. 3-5 earthquakes are recognised at different sites, with the last earthquake occurring 3.3 ka and a mean recurrence interval of 3-4 ka on the Vernon Fault. When combined with the paleseismic records from the Awatere and Cloudy faults I find that separate faults ruptured at similar times, suggesting a connectivity of the faults, as separate faults could mutually rupture during one earthquake or an earthquake could subsequently trigger an earthquake on a nearby fault. Finally I present the finite slip of geologic units and use these data as well as the late Quaternary slip data to describe the evolution of the fault network. I propose that the fault network at the NE end of the Awatere fault has stepped northwards into several splays, caused by clockwise rotation of the NE tips of the Marlborough faults.</p>

Neotectonics, Kinematics, and Evolution of the Vernon, Awatere, and Cloudy Faults of the Marlborough Fault System, New Zealand

<p>The coastal Awatere, Vernon, and Cloudy faults are bent and mutually intersecting, forming a complexly deforming dextral-oblique fault network. To try to explain the kinematic, paleoseismic and evolutionary complexities of this network, I present the results of an investigation into the rates, timing, and direction of slip on the faults within the network; which bifurcate eastwards from the central Awatere fault at the northeast end of the Marlborough Fault System. Displacements of dated and nondated late Quaternary features by the three faults were measured both onshore and offshore, constraining the kinematics of the fault network. The Vernon fault oddly maintains a dextral-reverse structure although it varies over 90° in strike and the Cloudy and coastal Awatere faults change from nearly pure strike slip to having a normal component eastwards. These data indicate that the fault-bounded blocks between the coastal Awatere, Vernon and Cloudy faults are rotating anticlockwise about a vertical axis relative to the block to the north of the fault system. Slip-rate data also indicate that of the 6 ± 1 mm/yr of slip on the central Awatere Fault, 1.1 ± 0.6 mm/yr has been partitioned ENE onto the coastal Awatere Fault and <4.9 mm/yr has been partitioned NNE onto the Vernon Fault. A slip-rate shortage in the splays of the Vernon Fault in the Vernon Hills is caused by a combination of unsighted faults and rotation of smaller splay-bounded blocks within the Vernon Hills. Paleoseismic records on the Vernon Fault were analysed onshore in a trench and offshore on seismic lines, with the records in good agreement. 3-5 earthquakes are recognised at different sites, with the last earthquake occurring 3.3 ka and a mean recurrence interval of 3-4 ka on the Vernon Fault. When combined with the paleseismic records from the Awatere and Cloudy faults I find that separate faults ruptured at similar times, suggesting a connectivity of the faults, as separate faults could mutually rupture during one earthquake or an earthquake could subsequently trigger an earthquake on a nearby fault. Finally I present the finite slip of geologic units and use these data as well as the late Quaternary slip data to describe the evolution of the fault network. I propose that the fault network at the NE end of the Awatere fault has stepped northwards into several splays, caused by clockwise rotation of the NE tips of the Marlborough faults.</p>

Scheimpflug Topography Oriented Adequate Repositioning of a Misaligned Free Flap after Laser in situ Keratomileusis

This report describes a case of Scheimpflug topography oriented adequate repositioning of a misaligned thick free flap after laser in situ keratomileusis (LASIK). A 24-year-old patient consulted for irregular astigmatism and disoriented free right eye flap. The patient previously underwent binocular LASIK at a private clinic. During the right eye surgery, the flap was repositioned after laser ablation due to the free flap. The free flap was not repositioned to its original configuration due to insufficient preoperative corneal marking. On examination, the uncorrected visual acuity was 0.4, and refractive power was +2.00 Dsph with −4.25 Dcyl axis 66 in the right eye. Scheimpflug topography revealed irregular right eye astigmatism. The sagittal curvature of topography showed a 40° counterclockwise misalignment of the steep axis of the cornea. The free flap was repositioned by 40° clockwise rotation. After this, the refractive corneal power improved to −1.00 Dsph with −1.00 Dcyl Axis 19 in the right eye. The uncorrected and best-corrected visual acuity improved to 20/30 and 20/25 (x − 0.25Dsph −1.25 Dcyl A20), respectively. This is the first report on free flap repositioning using Scheimpflug topography. As proper flap positioning was compromised because of the free LASIK flap with no preoperative corneal marking, the flap was effectively repositioned using Scheimpflug topography.