Soft Expansion Research Articles

Double-soft limits of gluons and gravitons

The double-soft limit of gluon and graviton amplitudes is studied in four dimensions at tree level. In general this limit is ambiguous and we introduce two natural ways of taking it: a consecutive double-soft limit where one particle is taken soft before the other and a simultaneous limit where both particles are taken soft uniformly. All limits yield universal factorisation formulae which we establish by BCFW recursion relations down to the subleading order in the soft momentum expansion. These formulae generalise the recently discussed subleading single-soft theorems. While both types of limits yield identical results at the leading order, differences appear at the subleading order. Finally, we discuss double-scalar emission in $$ \mathcal{N}=4 $$ super Yang-Mills theory. These results should be of use in establishing the algebraic structure of potential hidden symmetries in the quantum gravity and Yang-Mills S-matrix.

Use of a Titanium Mesh "Shelter" Combined with the Soft Tissue Matrix Expansion (Tent Pole) Grafting in the Reconstruction of a Severely Resorbed Edentulous Mandible. Technical Note.

Patients wearing complete dentures for a long time usually exhibit lack of bone and keratinized mucosa in the bearing area due to bone resorption. The patients suffering from this phenomenon usually have unstable and non-retentive complete denture, which result in constant trauma to the mucosa, pain, functional limitations and worsening of facial esthetics. An innovative technique has been described in which a novel surgical approach using osseointegrated dental implants as "tent poles" was applied concomitant with particulate autogenous bone graft. The authors claim that the control and maintenance of the surgically expanded soft tissue volume should prevent graft resorption in the long term. Nevertheless, resorption of the bone graft is usually more significant where the bone mass is poorer, in the mandibular body. This paper describes a case of severely resorbed edentulous mandible in which the "tent pole" technique was applied with some modifications. Use of the titanium mesh "shelters" and two additional implants was effective in "protecting" the bone graft in the posterior portion of the mandibular body increasing bone mass volume in this area. Furthermore, we believe that this kind of graft "protection" on the whole residual alveolar ridge can increase the width of bone mass gain optimizing the "tent pole" technique.

A note on soft factors for closed string scattering

In this note, it is shown that closed string graviton scattering amplitudes obey the same subleading soft limit as field theory graviton scattering amplitudes. The result is derived using a combination of recent results and methods including the subleading soft expansion for type I open string gluon disk scattering amplitudes, the single value projection for multiple ζ values, and the KLT relations in field and string theory.

Rehabilitation of a Severely Atrophic Mandible Using Soft Tissue Matrix Expansion (Tent-Pole).

Abstract Abstract It is a demanding process to restore edentulous patients with a severely resorbed mandible. These patients using complete dentures may have many problems such as poor retention, soreness of the soft tissues, and difficulties with eating and speech. Implant-supported restorations are a known solution for them. However, there are some edentulous patients with extreme resorption of the mandibular alveolar bone in whom the bone volume is so minimal, and it is impossible to place implants without performing bone grafting procedures. Soft tissue matrix expansion technique using dental implants as tent-poles has been presented to increase bone height. This clinical report explains how to perform soft tissue matrix expansion technique step by step and describes the rehabilitation of a patient with soft tissue matrix expansion approach, implants and a mandibular implant-supported fixed dental prosthesis.

Constraining subleading soft gluon and graviton theorems

We show that the form of the recently proposed subleading soft graviton and gluon theorems in any dimension are severely constrained by elementary arguments based on Poincar\'e and gauge invariance as well as a self-consistency condition arising from the distributional nature of scattering amplitudes. Combined with the assumption of a local form as it would arise from a Ward identity the orbital part of the subleading operators is completely fixed by the leading universal Weinberg soft pole behavior. The polarization part of the differential subleading soft operators in turn is determined up to a single numerical factor for each hard leg at every order in the soft momentum expansion. In four dimensions, factorization of the Lorentz group allows to fix the subleading operators completely.

Real-virtual contributions to the inclusive Higgs cross-section at N3LO

Abstract We compute the contributions to the N3LO inclusive Higgs boson cross-section from the square of one-loop amplitudes with a Higgs boson and three QCD partons as external states. Our result is a Taylor expansion in the dimensional regulator ϵ, where the coefficients of the expansion are analytic functions of the ratio of the Higgs boson mass and the partonic center of mass energy and they are valid for arbitrary values of this ratio. We also perform a threshold expansion around the limit of soft-parton radiation in the final state. The expressions for the coefficients of the threshold expansion are valid for arbitrary values of the dimension. As a by-product of the threshold expansion calculation, we have developed a soft expansion method at the integrand level by identifying the relevant soft and collinear regions for the loop-momentum.

The Impact of the Financial Crisis on EU Economic Governance: A Struggle between Hard and Soft Law and Expansion of the EU Competences?

The EU’s crisis response of introducing stricter economic governance has broadened its scope of interference in national policies significantly. This triggers questions on the effectiveness and legitimacy of hard and soft governance in a multi-level setting. Based on two examples the article illustrates the changing role of law in a globalised world and the consequential tensions. It thus provides input to further explore the concept of global law.

The Tent Pole Splint: A Bone-Supported Stereolithographic Surgical Splint for the Soft Tissue Matrix Expansion Graft Procedure

This report details the use of computer-aided planning and intraoperative stereolithographic direct-bone-contact surgical splints for the accurate extraoral placement of dental implants in the soft tissue matrix expansion (tent pole) graft of the severely resorbed mandible.

Poster 11: The Tent Pole Splint: A Bone-Supported Stereolithographic Surgical Splint for Extra-Oral Dental Implant Placement With the Soft Tissue Matrix Expansion Graft (Tent Pole) Procedure

Statement of the Problem: The dental implant rehabilitation of the severely resorbed mandible utilizing the soft tissue matrix expansion graft can be complicated due to the extraoral placement of the dental implants. Without direct visualization of the opposing arch during surgery, misangulation and malposition of the implants may occur. This is a description of a technique that allows for fabrication of a bone-supported stereolithographic surgical implant splint, the tent pole splint, for use during the extraoral endosseous implant placement during the soft tissue matrix expansion graft (tent pole) procedure for the reconstruction of the severely resorbed mandible.

Severely Resorbed Mandible Treated by Soft Tissue Matrix Expansion (Tent Pole) Grafts: Case Report

The functional rehabilitation for severely resorbed mandibles has been a challenge for dentists and oral surgeons. We present a 2-year follow-up case of severely resorbed mandibles successfully treated by soft tissue matrix expansion and cranial bone graft with nonremovable screw-retained acrylic resin prosthesis supported by 4 dental implants.

Kelvin waves with helical Beltrami flow structure

In this work we show that when an inviscid axisymmetric Rankine flow experiences a soft expansion, rotating Kelvin waves can be excited. Downstream of the region where the expansion occurs (the transition region) the resulting flow can be expressed as the addition of a Rankine and a Beltrami flow. The Beltrami constant is determined from the Rankine upstream flow, and the helix pitch of the n=1 mode results from the boundary conditions downstream. Finally, a discussion of the process leading to oscillatory flow and a conjecture about the topological background that sustains the Beltrami flow structure are offered.

Metastatic Mandibular Retinoblastoma in a Child Reconstructed With Soft Tissue Matrix Expansion Grafting: A Preliminary Report

Retinoblastoma is a congenital malignant neoplasm of retinal tissue. Reports of metastasis to the mandible are rare. Successful retinoblastoma management has led to a dramatic improvement in survival rates. Increasing numbers of surviving patients require reconstruction of the defects caused by the ablation of such metastasis. This article describes the management of a pediatric mandibular defect secondary to the resection of a metastatic retinoblastoma. A unique application of the soft tissue matrix expansion technique, otherwise known as the "tent-pole" graft, which has been previously described in adults with severe mandibular atrophy, was utilized in the pediatric patient. The soft tissue matrix expansion grafting technique can be successfully utilized in the reconstruction of ablative defects in pediatric patients.

The fabrication and use of an extraoral surgical guide for implant placement coincident with soft tissue matrix expansion grafts: A clinical report

During soft tissue matrix expansion (tent pole) graft (STMEG) surgery, the traditional intraoral surgical guide for dental implant placement cannot be used because the surgery is initiated and maintained outside the oral cavity. The essential records established from an intraoral surgical guide must be transferred to an extraoral surgical guide. This clinical report describes the fabrication and use of an extraoral surgical guide employed during STMEG surgery.

Definitive CAD/CAM‐Guided Prosthesis for Immediate Loading of Bone‐Grafted Maxilla: A Case Report

The reconstruction of a functional occlusion in the presence of severe residual ridge resorption remains a significant challenge for maxillofacial surgeons and prosthodontists. Removable appliances are unsuccessful in severely resorbed cases and the advanced degree of bone loss precludes conventional implant-retained prostehesis. In recent years, bone graft reconstruction of the maxilla and the mandible has been advocated to reverse the debilitating effects of alveolar ridge resorption. The surgical objective was the reconstruction of the osseous platform of the jaws, thereby allowing implant-retained definitive prosthetic rehabilitation utilizing the Teeth-in-an-Hour concept within 4 months. A completely edentulous patient received bone grafts from the posterior iliac crest to augment both the maxillary and mandibular alveolar ridges. The manmandible was augmented using Marx's "soft issue matrix expansion procedure" and was restored in the conventional manor using an impression and a milled framework. The maxilla underwent "inlay/onlay" bone graft augmentation of the right and left maxilla at the same time as the mandiblular procedure. Implant placement was at 4 months post-bone graft reconstruction. Immediate loading of implants into a bone graft using Nobel Biocare's Teeth-in-an-Hour protocol prelaunch was implemented. This included CT-based implant planning, simultaneous CAD/CAM fabrication of a surgical guide, a CNC-milled framework, flapless surgical placement of the implants, and immediate placement of a pre-fabricated definitive prosthesis. This approach reduced the time necessary for an edentulous patient to transform from severely atrophic alveolar support to implant-retained maxillary and mandibular prosthetic restorations. Immediate loading with an implant retained definitive prosthesis using a bone graft-reconstructed osseous platform was also performed. The Teeth-in-an-Hour concept was utilized to restore bone grafted augmentation of the maxilla with immediate loading of a definitive prosthesis within 4 months. The remarkable accuracy of the software, minimally invasive and short surgery and treatment time, uneventful quick recovery with minimal discomfort is a benefit not only to the patient, also to the treating team.

A New Osteotomy Design for Surgical Expansion of the Maxilla: The Oblique Maxillary Sagittal Osteotomy

i o ransverse deficiency of the maxilla is not uncomon, and is often associated with other dentofacial eformities. Attempts to surgically increase the ransverse dimension of the maxilla are associated ith significant relapse potential, and are considered o be the most unstable orthognathic surgical proceure. In an attempt to overcome the relapse associted with surgical expansion of the maxilla, surgeons ave proposed a variety of modifications, including idline cuts with parasagittal mucosal releasing inciions, placement of grafts, and staging the procedure ith the use of distraction (surgical assisted palatal xpansion). Steinhauser described a midline osteotmy for maxillary expansion in 1972. However, the ost common osteotomy design includes unilateral r bilateral paramedian sagittal osteotomies as decribed by Obwegeser in 1969. Paramedian osteotoies are recommended to position the osteotomy in n area of thick palatal mucosa in an attempt to educe the incidence of soft tissue perforations and llow maximal expansion. Unfortunately, this places he osteotomy in an area of thin bone, which inreases the chance of fibrous union between the axillary segments. From 1997 to 2003, the senior uthor (D.M.C.) performed 121 segmental osteotoies using a midline osteotomy to take advantage of he thicker bone stock in this area. In December

Reconstruction of trauma, tumor, and major pre-prosthetic defects

Reconstruction of both maxillary and mandibular defects requires scientific knowledge and surgical skills in soft tissue procedures as well as bone grafting techniques. The classic mandibular continuity defect can be reconstructed today with excellent predictability using straightforward cancellous marrow with platelet rich plasma growth factor additions within crib containments of allogeneic bone, rigid reconstruction plates, or even titanium basket cribs. Each location has its own surgical approach and challenges. Reconstructing the hemimandibular defect with a missing condyle may require a costochondral graft, a titanium condylar replacement, or an allogeneic condyle in combination with cancellous marrow. Defects across the mid-line require cribs that duplicate the arch form and have unique fixation requirements. Trauma defects often require a preliminary “set-up” surgery to debride foreign bodies and sequestra as well as align the remaining bone segments. Thin severely resorbed mandibles can be reconstructed to bone heights of 15 mm with a tenting concept using dental implants along with cancellous marrow grafting techniques. Each of these examples illustrates a separate soft tissue management, bone regeneration concept and a functionality of the reconstruction to mature and maintain the bone graft. Maxillary reconstruction today may require only an obturator denture. However, in patients where the obturator denture leaks, does not seal, or lacks sufficient retention, biologic reconstruction becomes necessary. This often takes the form of a temporalis muscle flap to provide vascular soft tissue and to close any oral-antral or oral-nasal communication. Bone grafting via cortical cancellous blocks lag screwed into host maxillary bone and supplemented with additional cancellous marrow and platelet rich plasma reconstructs the alveolar processes of the maxilla with excellent outcomes. The early placement of dental implants and their immediate or early loading will mature and maintain the bone via functional loading. Maxillary contour grafting and orbital/nasal grafting is best accomplished with calvarial bone grafts, which have a similar contour to the maxilla and have a reduced remodeling volume loss due to their diploic vascular channels. References Carlson ER, Marx RE: Mandibular reconstruction with particulate bone and cancellous marrow grafts. Factors resulting in predictable reconstruction of the mandible, in Washington P, Evan J (eds): Controversies in Oral and Maxillofacial Surgery. Philadelphia, PA, Saunders, 1994, chap 24, pp 288–300 Marx RE, Schellenberger T, Wimsatt J, et al: Severely resorbed mandibles, predictable reconstruction with soft tissue matrix expansion (tent pole) grafts. J Oral Maxillofac Surg 60: 2002. Marx RE, Schiff WJ, Saunders TM: Reconstruction and rehabilitation of cancer patients, in Fonseca RA, Davis HW (eds): Reconstructive Pre-Prosthetic Oral and Maxillofacial Surgery. Philadelphia, PA, Saunders, 1995, chap 31, pp 1057–1133

Severely resorbed mandible: Predictable reconstruction with soft tissue matrix expansion (tent pole) grafts

Purpose: Attempts to reconstruct the severely resorbed mandible (≤6 mm) have historically been unsuccessful and often been complicated by fracture, fistulas, and neurosensory loss. In the past, bone grafts to these severely resorbed mandibles have rapidly resorbed due to a soft tissue volume deficiency that contracts about the graft. Material and Methods: A novel surgical approach using dental implants as “tent poles,” along with bone grafting, is described, and the long-term follow-up of 64 cases is presented. Results: The results revealed that all 64 grafts maintained 15 mm of bone height, with a follow-up ranging from 3 to 10 years and a mean follow-up of 4.9 years. The starting bone heights ranged from 3 to 6 mm, with a mean height of 4.8 mm. The mean bone height gain was 10.2 mm, with a range of 9 to 13 mm. All patients progressed to a functional denture that remained in function at the time of their follow-up. Short-term parasthesia (≤3 weeks) was noted in 17.1% of patients, but no permanent neurosensory disturbance was noted. In these 64 cases, 356 dental implants were placed and 354 were osseointegrated (99.5%) and functioning at the time of follow-up (≥3 years). Conclusions: The novel strategy of this surgery whereby bone grafts consolidate and maintain their volume by dental implants that creates a tenting effect offers predictable long-term reconstruction of the severely resorbed mandible without the complications observed with other approaches. © 2002 American Association of Oral and Maxillofacial Surgeons J Oral Maxillofac Surg 60:878-889, 2002

Effect of wet incubation time and temperature on infection, and of storage time and temperature on soft rot lesion expansion in potatoes inoculated withErwinia carotovora ssp.Carotovora

Infection and lesion expansion studies were carrried out on potato tubers. In the infection study, the tubers were inoculated withErwinia carotovora ssp.carotovora (Ecc) and exposed to incubation temperatures of 10–25 °C for 3–48 h of wetness. In the lesion expansion study, the tubers were exposed to 12 h of wetness at 20 °C to establish infection, and then·stored at temperatures of 4–16 °C for 15–90 d, at 95% RH. The volume of diseased tissue was determined and the data were transformed to proportion of maximum volume diseased (PVD). Infection was close to zero for 3 and 6 h wet incubation time, regardless of incubation temperature, and reached the maximum in 12 h of wetness at 20 °C. Significant lesion expansion occurred at a storage temperature of 16 °C after about 60 d of storage time. Cubic models of infection and lesion expansion potentials explained 95 and 96% of the variations in infection and lesion expansion, respectively.

A new field theoretic approach to criticality

A reorganized perturbation expansion with a propagator of soft infrared behavior is used to study the critical behavior of the mass gap. The condition of relativistic covariance fixes the form of the soft propagator. Finite approximants to the correlation critical exponent can be obtained in every order of the modified, soft perturbation expansion. Alternatively, a convergent series of exponents in large orders of the soft perturbation expansion is provided by the renormalization group in all spatial dimensions, 1 ⩽ D ⩽ 3. The result of the ϵ-expansion is recovered in the D → 3 limit.