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OBJECTIVES: The aims of this study were to test whether or not the application of an in situ-formed synthetic polyethylene glycol hydrogel (PEG) used as a biodegradable membrane for guided bone regeneration with a variety of graft materials and ambient oxygen or hyperbaric oxygen (HBO) environments would result in enhanced bone regeneration, and to observe the histologic and histomorphometric aspects of bone healing of the calvarial defects with and without a PEG membrane. STUDY DESIGN: Thirty adult, skeletally mature, male New Zealand white rabbits were randomly divided into 3 groups of 10 animals each. Bilateral 15-mm-diameter critical-size defects were created in the parietal bones of each animal. Group 1 served as a control with unfilled bilateral calvarial defects, group 2 had bilateral calvarial defects filled with morcelized autogenous calvarial bone, and group 3 had bilateral calvarial defects filled with a biphasic calcium phosphate ceramic. One of the calvarial defects was randomly protected with a PEG resorbable liquid membrane in each animal. Five animals from each group underwent a course of HBO treatment (2.4 ATA 100% oxygen for 90 minutes 5 days a week for 4 weeks) and the other 5 served as control and did not receive any supplemental oxygen (normobaric). The animals were killed 6 weeks after their surgery, and their parietal bones were harvested. The specimens were analyzed with microscopic computerized tomography (microCT) scans and histomorphometrics. RESULTS: The unfilled normobaric control bony defects did not heal, proving the critical-size nature of these defects. The presence of autogenous bone or bone ceramic in the defects increased the bone volume fraction and bone mineral density of the defects (P < .001). The presence of a membrane in the ungrafted and autogenous bone grafted defects resulted in a decrease in the corrected bone volume fraction (P = .002) but not in the bone ceramic grafted defects (P = .580). Bony healing of defects where the membrane was unsupported was compromised; the membrane did not maintain the desired bone regeneration volume with the unfilled and autogenous bone grafted groups. The PEG resorbable liquid membrane worked best with the bone ceramic material. HBO did not ameliorate the healing of the autogenous bone graft or ceramic filled defects in the 6-week time period of this study. CONCLUSIONS: Although the PEG resorbable liquid membrane is easy to use and forms an occlusive layer, caution is recommended when using the membrane over an unsupported defect. HBO did not ameliorate bony healing with the membrane at the early 6-week time point. The authors recommend future assessment with HBO at the 12-week time point. [ABSTRACT FROM AUTHOR]

Objectives: To implement and evaluate the accuracy of a prototype dynamic computer-assisted surgery (CAS) system for implant osteotomy preparation and compare its accuracy vs. three commercial static CAS systems and the use of an acrylic stent., Material and Methods: Eight osteotomies were prepared in radiopaque partially edentulous mandible and maxilla typodonts. After cone-beam CT acquisition, DICOM files were imported into a prototype dynamic, and three static CAS systems (NobelClinician, Simplant, and CoDiagnostiX). Implant placements were planned to replicate the existing osteotomies and respective guides were requisitioned, along with one laboratory-made acrylic guide. The eight osteotomies per jaw were transferred to one typodont pair mounted in a manikin in a clinical setting and the process was repeated for four additional pairs. The 80 (two jaws × eight holes × five pairs) osteotomies were filled with radiopaque cement in-between the testing series. Three clinicians experienced with the use of the static CAS softwares used in this study prepared each 400 (80 holes × five modalities) osteotomies. One clinician repeated the experiment twice, resulting in a total of 2000 (five clinicians × 400) osteotomies. The lateral, vertical, total, and angular deviations of the actual vs. the original osteotomies in the master typodonts were measured using stereo optical tracking cameras. Linear regression statistics using generalized estimating equations were used for comparisons between the five modalities and omnibus chi-square tests applied to assess statistical significance of differences., Results: The prototype dynamic CAS system was as accurate as other implant surgery planning and transfer modalities. The dynamic and static CAS systems provide superior accuracy vs. a laboratory-made acrylic guide, except vertically. Both dynamic and static CAS systems show on average <2 mm and 5 degrees error. Large deviations between planned and actual osteotomies were occasionally observed, which needs to be considered in clinical practice., Conclusions: The prototype dynamic CAS system was comparably accurate to static CAS systems., (© 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Osteopetrosis is one cause of osteosclerosis and may result in such serious oral complications as osteomyelitis and exposed necrotic bone. Dentists should be aware of patients with the disease because of its effect on osteoclast function, which results in impaired wound healing. The purpose of this paper is to review the causes, pathogenesis and differential diagnosis of osteopetrosis and to provide guidance to dentists on the management of patients with osteopetrosis.

Bisphosphonate-associated osteonecrosis (BON) may result in serious oral complications, such as osteomyelitis and chronic exposure of necrotic bone. Dentists must be familiar with this disorder and pay special attention to all patients on bisphosphonate therapy due to their defective osteoclast function and reduced osseous tissue vascularity, leading to impaired wound healing. The purpose of this paper is to review the history and pathogenesis of BON, discuss its differential diagnosis, provide guidance to dentists on possible measures to prevent BON and review the management of patients with BON.

In a previous paper, the nature of venous sequelae were described, and the etiologic factors of mechanical and drug injury related to the development of superficial vein thrombosis were addressed. This paper deals with additional factors that may be involved or that have been exposed for reducing or eliminating the problem.

Maxillary nerve blockade is not commonly used by general practitioners due to a lack of experience with the techniques involved and the fear of iatrogenic damage. Nevertheless, it represents an excellent method of producing profound anesthesia in the maxilla, with definite indications in selected instances. The anatomy and techniques associated with the maxillary block, as well as the indications, contraindications and complications are reviewed, and the use of the greater palatine foramen approach to treat a patient with a facial abscess is described.

Idiopathic myelofibrosis is a hematologic myeloproliferative disorder characterized by progressive marrow fibrosis, extramedullary hematopoiesis, and a leukoerythroblastic anemia. Consequently there are frequent secondarily precipitated multiple systems problems. This is the first report of this entity presenting with orofacial findings. The histopathogenesis, clinical presentation, and the therapeutic goals of treatment are reviewed.