Incidental findings on craniomaxillofacial cone beam computed tomography in orthodontic patients.

PURPOSE: Cone beam computed tomography (CBCT) in orthodontics is increasingly used for detecting impacted or ectopic teeth or for orthognathic and cleft lip and palate treatment. Incidental findings (IFs) are frequently encountered and often relevant. The aim of this study was to detect the prevalence of relevant pathologies on CBCT scans of orthodontic patients. METHODS: Over a 6-year period, incidental imaging findings were analyzed in 345 CBCT scans (181 men; 164 women; age 16.3 ± 8.4 years), and subdivided into dental (Group 1), skeletal (Group 2), sinunasal (Group 3), and infrequent other pathologies (Group 4). RESULTS: A total of 502 IFs were detected in 345 patients (1.4 IFs per patient, on average). Most IFs were found in Group 1 (358 IFs; 71.3%), followed by Group 2 (129 IFs; 25.7%), Group 3 (14 IFs; 2.8%), and Group 4 (1 IF; 0.2%). There were 119 (34.5%) patients with a missing wisdom tooth, 94 (27.3%) with dental aplasia, 71 (20.6%) with dislocations, 33 (9.6%) with partial opacifications, and 27 (7.8%) with signs of sinusitis. CONCLUSIONS: This study found that IFs in orthodontic CBCT scans are frequently encountered, even in younger orthodontic patients. When interpreting CBCT scans, orthodontists should be aware of potential relevant IFs that may require further investigation, change patients' treatment or affect their quality of life.

Possible pulmonary Rhizopus oryzae infection in a previously healthy child after a near-drowning incident.

This article reports on a previously healthy 17-month-old boy who developed pulmonary mucormycosis after a near-drowning incident in a goose pond. The patient survived without neurological sequelae and recovered, under treatment with amphotericin B, from the rare and often invasive fungal infection with Rhizopus spp., usually occurring in immunodeficient patients.

Options in virtual 3D, optical-impression-based planning of dental implants.

If a 3D radiograph, which in today's dentistry often consists of a CBCT dataset, is available for computerized implant planning, the 3D planning should also consider functional prosthetic aspects. In a conventional workflow, the CBCT is done with a specially produced radiopaque prosthetic setup that makes the desired prosthetic situation visible during virtual implant planning. If an exclusively digital workflow is chosen, intraoral digital impressions are taken. On these digital models, the desired prosthetic suprastructures are designed. The entire datasets are virtually superimposed by a "registration" process on the corresponding structures (teeth) in the CBCTs. Thus, both the osseous and prosthetic structures are visible in one single 3D application and make it possible to consider surgical and prosthetic aspects. After having determined the implant positions on the computer screen, a drilling template is designed digitally. According to this design (CAD), a template is printed or milled in CAM process. This template is the first physically extant product in the entire workflow. The article discusses the options and limitations of this workflow.

Cerec meets Galileos--integrated implantology for completely virtual implant planning.

The greatest key to successful implant therapy is proper placement of the implant in the jaw bone. The key to proper placement is careful preoperative planning. When planning implant treatment, it is important to take the relevant anatomical features and their later prosthetic consequences into account. This is done using a radiographic template of the planned restoration, which until now had to be made by a dental technician. The radiographic template must be inserted in the patient's mouth during radiographic imaging so that the dentist can visualize the prosthetic plan. Implant planning is thus performed according to the backward planning principle. In the novel, fully digital approach to dental implant planning presented here, the prosthetic proposal is designed using computer-aided design software and integrated into a three-dimensional radiograph. This article explains how the technology works and reviews the available data. In addition, the clinical workflows for the SiCAT Optiguide and Sirona Cerec Guide virtual implant planning methods will be described and compared with conventional implant planning methods. Finally, the indications and countraindications for the two methods will be discussed.

Accuracy of chairside-milled CAD/CAM drill guides for dental implants.

PURPOSE: To describe a chairside method for producing implant guides based solely on digital data and present a first assessment of in vitro accuracy on plaster models. MATERIAL AND METHODS: Twenty-four implants were planned and pilot drillings were performed according to a new protocol, which is based on the registration of CBCT and CAD/CAM data. Chairside-milled one-piece drill guides were used to transfer the virtual plan into reality. Accuracy measurements were acquired. RESULTS: Chairside-milled drill guides were successfully fabricated and accuracy for pilot drillings was between 0.17 and 1.3 mm. CONCLUSION: Within the limits of this experimental study, chairside-milled drill guides are feasible and do not require any preparation before CBCT scanning.

A paradigm shift in orthognathic surgery? A comparison of navigation, computer-aided designed/computer-aided manufactured splints, and "classic" intermaxillary splints to surgical transfer of virtual orthognathic planning.

PURPOSE: Advances in computers and imaging have permitted the adoption of 3-dimensional (3D) virtual planning protocols in orthognathic surgery, which may allow a paradigm shift when the virtual planning can be transferred properly. The purpose of this investigation was to compare the versatility and precision of innovative computer-aided designed and computer-aided manufactured (CAD/CAM) surgical splints, intraoperative navigation, and "classic" intermaxillary occlusal splints for surgical transfer of virtual orthognathic planning. MATERIAL AND METHODS: The protocols consisted of maxillofacial imaging, diagnosis, virtual orthognathic planning, and surgical planning transfer using newly designed CAD/CAM splints (approach A), navigation (approach B), and intermaxillary occlusal splints (approach C). In this prospective observational study, all patients underwent bimaxillary osteotomy. Eight patients were treated using approach A, 10 using approach B, and 12 using approach C. These techniques were evaluated by applying 13 hard and 7 soft tissue parameters to compare the virtual orthognathic planning (T0) with the postoperative result (T1) using 3D cephalometry and image fusion (ΔT1 vs T0). RESULTS: The highest precision (ΔT1 vs T0) for the maxillary planning transfer was observed with CAD/CAM splints (<0.23 mm; P > .05) followed by surgical "waferless" navigation (<0.61 mm, P < .05) and classic intermaxillary occlusal splints (<1.1 mm; P < .05). Only the innovative CAD/CAM splints kept the condyles in their central position in the temporomandibular joint. However, no technique enables a precise prediction of the mandible and soft tissue. CONCLUSIONS: CAD/CAM splints and surgical navigation provide a reliable, innovative, and precise approach for the transfer of virtual orthognathic planning. These computer-assisted techniques may offer an alternate approach to the use of classic intermaxillary occlusal splints.

PET/MR in children. Initial clinical experience in paediatric oncology using an integrated PET/MR scanner.

Use of PET/MR in children has not previously been reported, to the best of our knowledge. Children with systemic malignancies may benefit from the reduced radiation exposure offered by PET/MR. We report our initial experience with PET/MR hybrid imaging and our current established sequence protocol after 21 PET/MR studies in 15 children with multifocal malignant diseases. The effective dose of a PET/MR scan was only about 20% that of the equivalent PET/CT examination. Simultaneous acquisition of PET and MR data combines the advantages of the two previously separate modalities. Furthermore, the technique also enables whole-body diffusion-weighted imaging (DWI) and statements to be made about the biological cellularity and nuclear/cytoplasmic ratio of tumours. Combined PET/MR saves time and resources. One disadvantage of PET/MR is that in order to have an effect, a significantly longer examination time is needed than with PET/CT. In our initial experience, PET/MR has turned out to be an unexpectedly stable and reliable hybrid imaging modality, which generates a complementary diagnostic study of great additional value.

Accuracy of cone beam computed tomography in assessing peri-implant bone defect regeneration: a histologically controlled study in dogs.

OBJECTIVE: To assess the accuracy of cone-beam computed tomography (CBCT) in terms of buccal bone-wall configuration and peri-implant bone defect regeneration after guided bone regeneration (GBR). MATERIAL AND METHODS: Titanium implants were inserted into standardized box-shaped defects in the mandible of 12 foxhounds. Defects of one side were augmented following the principle of GBR, while the other side was left untreated. Radiological evaluation was performed using CBCT and compared with histomorphometrical measurements of the respective site serving as a validation method. RESULTS: Non-augmented control sites providing a horizontal bone width (BW) of<0.5 mm revealed a significantly lower accuracy between the radiological and the histological evaluation of the buccal defect depth (1.93 ± 1.59 mm) compared with the group providing a BW of >0.5 mm (0.7 ± 0.7 mm) (P<0.05, Mann-Whitney U-test). In GBR-treated defects, the subgroup <0.5 mm (1.49 ± 1.29 mm) revealed a significantly higher difference between CBCT and histology compared with >0.5 mm (0.82 ± 1.07) (P>0.05, Mann-Whitney U-test). However, a radiological discrimination between original bone, integrated and non-integrated bone substitute material was not reliable. Additionally, it was found that a minimum buccal BW of 0.5 mm was necessary for the detection of bone in radiology. CONCLUSION: The evaluation of peri-implant bone defect regeneration by means of CBCT is not accurate for sites providing a BW of <0.5 mm. Moreover, a safe assessment of the success of the GBR technique is not possible after the application of a radiopaque bone substitute material.

Evaluation of maxillary sinus anatomy by cone-beam CT prior to sinus floor elevation.

PURPOSE: Surgical complications during sinus floor elevation are frequently caused by septa in the maxillary sinus. In this study, the prevalence of septa was retrospectively determined via three-dimensional imaging to assess the necessity for appropriate imaging prior to sinus floor elevation. MATERIALS AND METHODS: The cone-beam computed tomography scans of 1,029 consecutive patients were evaluated to assess the prevalence of septa, taking into account patient age and sex as well as the number and orientation of septa and their locations. If septa were present, the height was measured and the orientation was determined. RESULTS: Septa were found in 47% of patients and 33.2% of sinuses. There was no statistical difference in prevalence with respect to age, sex, or side. Most patients with septa showed one septum in one sinus (24.6%); 13.7% showed one septum in each sinus. Other combinations (up to three septa per sinus) were found in 8.7% of patients. Septa were most commonly located in the first molar region (256 septa), followed by the second molar region (225 septa), the third molar region (144), second premolar region (136), the first premolar region (44), and the canine region (5). The mean septal height was 11.7 +/- 6.08 mm for septa in a sagittal orientation (n = 206, 25.3%; maximum height of 37 mm) and 7.3 +/- 5.08 mm for those oriented transversely (n = 608, 74.7%; maximum height of 36 mm). The variance was larger for the sagittal orientation group (37.03 mm) than for transversely oriented septa (25.9 mm). CONCLUSION: Septa were found in 47% of the patients in this sample. Appropriate imaging prior to performing sinus surgery seems justified, since complications and the success rate of sinus floor elevation are clearly related to the presence of septa. Int J Oral Maxillofac Implants 2010;25:258-265.

Accuracy of a newly developed integrated system for dental implant planning.

OBJECTIVES: To evaluate the accuracy of the first integrated system for cone-beam CT (CBCT) imaging, dental implant planning and surgical template-aided implant placement. MATERIALS AND METHODS: On the basis of CBCT scans, a total of 54 implant positions were planned for 10 partially edentulous anatomical patient-equivalent models. Surgical guides were ordered from the manufacturer (SICAT). Two different types of guidance were assessed: for assessment of the SICAT system inherent accuracy vendor's titanium sleeves of 2 mm internal diameter and 5 mm length were utilized for pilot drills. The guide sleeves of the NobelGuide system were implemented for fully guided surgery and implant insertion. Deviations perpendicular to the implant axes at the crestal and apical end, as well as the angle deviations between the virtual planning data and the surgical results, were measured utilizing a follow-up CBCT investigation and referential marker-based registration. RESULTS: The SICAT system inherent mean deviation rates for the drilled pilot osteotomies were determined to be smaller than 500 mum even at the apical end. Mean angle deviations of 1.18 degrees were determined. Utilizing the NobelGuide sleeve-in-sleeve system for fully guided implant insertion in combination with the investigated template technology enabled to insert dental implants with the same accuracy. Crestal deviations, in general, were significantly lower than the apical deviations. CONCLUSION: Although hardly comparable due to different study designs and measurement strategies, the investigated SICAT system's inherent accuracy corresponds to the most favourable results for computer-aided surgery systems published so far. In combination with the NobelGuide surgical set for fully guided insertion, the same accuracy level could be maintained for implant positioning.

Comparison of cone-beam imaging with orthopantomography and computerized tomography for assessment in presurgical implant dentistry.

PURPOSE: To establish a basis for weighing the potential diagnostic and therapeutic benefits of three-dimensional cone-beam (CB) data sets in contrast to digital orthopantomography (OPG) and computerized tomography (CT) in implant dentistry. MATERIALS AND METHODS: Twenty-seven patients requiring implant surgery received a single presurgical CB scan. A follow-up digital OPG was taken within a maximal postsurgical period of 2 weeks. For comparison purposes, a control group of 29 patients receiving CT as well as CB diagnosis was analyzed. Image quality of the different modalities was ranked retrospectively by five experienced examiners (from excellent to insufficient) for up to 10 defined criteria, including general image quality and several specific structures. The results were analyzed statistically, and interobserver agreement was calculated using intraclass correlation coefficients (ICCs). RESULTS: The median rating for all investigated criteria was good for CB imaging and between good and insufficient for OPG in the dental implant group. Except for general image quality, statistical analysis showed that CB imaging was significantly superior to OPG imaging for all investigated anatomic structures. With a few exceptions, all investigated anatomic structures in CT and CB imaging were rated excellent in the control group. No significant difference between CT and CB imaging was detected in the control group for all investigated criteria. With a few exceptions, ICCs were higher for CB images than for OPG. In the control group, ICCs for CT and CB images were similar, with a few exceptions. CONCLUSION: The results of the present study confirm superior radiographic visualization for all important high-contrast structures in presurgical implant dentistry assessment for CB imaging in contrast to OPG and a CT-like degree of information for high-contrast structures in CB data sets. Clinically, however, the elevated radiation dosages transmitted by CB imaging must be taken into account.

Sleep-disordered breathing in orthodontic practice: Prevalence of snoring in children and morphological findings.

OBJECTIVES: The purpose of this work was to evaluate the prevalence of snoring and its correlation with cranial and upper airway morphology in young individuals with orthodontic treatment need. PATIENTS AND METHODS: Parents of 379 children were consecutively interviewed, using eight questions from a more comprehensive questionnaire about sleep behavior. A total of 100 patients (54 girls, 46 boys, average age 11.3 years) met the inclusion criteria. Based on the parents' interviews, the sample was divided into snorers (n = 53) and nonsnorers (n = 47). Using cephalograms obtained for initial orthodontic diagnostics, airway morphology was measured based on hyoid position and on the posterior airway space (PAS) dimensions at the maxillary, occlusal, and mandibular plane levels (PAS_NL, PAS_OCCL, PAS_ML). Mann-Whitney U testing, ANOVA, and Spearman's rank correlation coefficient were used for statistical analysis. RESULTS: Snoring was reported by 53 % of parents for 63 % (n = 29) of the boys and 44 % (n = 24) of the girls. Significant morphological differences were noted between snorers and nonsnorers. PAS dimensions were significantly reduced in the snorers compared to the nonsnorers at all three anatomical levels tested, which remained statistically significant when adjusted for age and gender. No differences between the two groups emerged for hyoid position or any of the vertical cranial parameters. A significant correlation between sagittal maxillary position (SNA) and PAS_NL was noted, indicating that larger SNA values were mildly associated with larger sagittal PAS dimensions at the maxillary level. CONCLUSION: This random sample of young patients with orthodontic treatment need was found to involve a high prevalence of parent-reported snoring. Characteristic features in cranial and upper airway morphology and thus differences between the snorers and nonsnorers were found.

Whole-Body Diffusion-Weighted Imaging in Chronic Recurrent Multifocal Osteomyelitis in Children.

OBJECTIVE: Chronic recurrent multifocal osteomyelitis/ chronic non-bacterial osteomyelitis (CRMO/ CNO) is a rare auto-inflammatory disease and typically manifests in terms of musculoskeletal pain. Because of a high frequency of musculoskeletal disorders in children/ adolescents, it can be quite challenging to distinguish CRMO/ CNO from nonspecific musculoskeletal pain or from malignancies. The purpose of this study was to evaluate the visibility of CRMO lesions in a whole-body diffusion-weighted imaging (WB-DWI) technique and its potential clinical value to better characterize MR-visible lesions. MATERIAL AND METHODS: Whole-body imaging at 3T was performed in 16 patients (average: 13 years) with confirmed CRMO. The protocol included 2D Short Tau Inversion Recovery (STIR) imaging in coronal and axial orientation as well as diffusion-weighted imaging in axial orientation. Visibility of lesions in DWI and STIR was evaluated by two readers in consensus. The apparent diffusion coefficient (ADC) was measured for every lesion and corresponding reference locations. RESULTS: A total of 33 lesions (on average 2 per patient) visible in STIR and DWI images (b = 800 s/mm2 and ADC maps) were included, predominantly located in the long bones. With a mean value of 1283 mm2/s in lesions, the ADC was significantly higher than in corresponding reference regions (782 mm2/s). By calculating the ratio (lesion to reference), 82% of all lesions showed a relative signal increase of 10% or higher and 76% (25 lesions) showed a signal increase of more than 15%. The median relative signal increase was 69%. CONCLUSION: This study shows that WB-DWI can be reliably performed in children at 3T and predominantly, the ADC values were substantially elevated in CRMO lesions. WB-DWI in conjunction with clinical data is seen as a promising technique to distinguish benign inflammatory processes (in terms of increased ADC values) from particular malignancies.

How early can one diagnose Cushing's disease? An early diagnosis in a case of prepubertal Cushing's disease.

BACKGROUND: Cushing's disease is very rare in children, and the diagnosis is frequently delayed by several years. OBJECTIVE: We report a case of prepubertal Cushing's disease with a medical history of only 9 months. This case illustrates the difficulties involved in diagnosing children at the early stage of the disease. CASE PRESENTATION: An 8-year-old prepubertal boy presented with rapid weight gain accompanied by a decreasing growth velocity and hirsutism. Thyroid function tests and growth factor levels were normal, thus excluding hypothyroidism and growth hormone deficiency. Cushing's syndrome was confirmed by elevated 24-h urinary free cortisol levels, increased diurnal cortisol levels, and a lack of cortisol suppression in the low-dose dexamethasone suppression test. Further tests to investigate the source of the hypercortisolism showed the following results: Basal morning adrenocorticotropic hormone (ACTH) was normal. The high-dose dexamethasone suppression test led to a 51% decrease in cortisol level. In the corticotropin-releasing hormone (CRH) test, ACTH and cortisol increased only by 28%. Repeated magnetic resonance imaging (MRI) finally revealed a microadenoma in the anterior pituitary, thus establishng the diagnosis of Cushing's disease. Upon diagnosis, the patient underwent transsphenoidal surgery. Histological analysis confirmed an ACTH-secreting pituitary adenoma. CONCLUSION: This case illustrates the difficulties associated with the clinical, biochemical, and radiological diagnoses of Cushing's disease in children. Early diagnosis remains a challenge because test results often do not match standard diagnostic criteria.

Comparison of different autografts for aural cartilage in aesthetic rhinoplasty: is the tragal cartilage graft a viable alternative?

Auricular cartilage is an important source of grafts for various reconstructive procedures such as aesthetic rhinoplasty. The purpose of this investigation was to compare tragal cartilage with auricular cartilage harvested from the concha and scapha, and describe its clinical viability, indications, and morbidity in rhinoplasty. A total of 150 augmentation rhinoplasties with a total of 170 grafts were included. The donor sites were tragus (n=136), concha (n=26), and scapha (n=8). The time needed to harvest the grafts, the donor site morbidity, and the indications for operation were recorded. The anthropometric changes to 4 auricular variables after the cartilage had been harvested were analysed and compared with those on the opposite side in 48 patients using Student's paired t-test. Intraobserver reliability was assessed using Pearson's intraclass correlation. The mean (SD) harvesting time was 27 (8) min for the concha, 4.5 (1.4) min for the tragus, and 5.7 (1.6) min for the scapha. The largest graft was taken from the concha (28×19 mm), followed by the tragus (20×12 mm), and the scapha (18×6 mm). The grafts were placed at the following sites: tip grafts (n=123), columella struts (n=80), shield (n=20), rim (n=17), and dorsal onlay (n=15). Harvesting tragal cartilage is safe, simple, fast, and has a low morbidity, but it can affect the patient's ability to wear earphones. Tragal cartilage is a good alternative for nasal reconstruction if a graft of no longer than 20 mm is required.

Evaluation of the course of the inferior alveolar nerve in the mental foramen by cone beam computed tomography.

PURPOSE: Implant placement in the edentulous anterior mandible is frequently performed to stabilize prosthetic superstructures. The position of the inferior alveolar nerve (IAN), especially in an atrophic mandible, has to be considered to position implants properly. In this study, the prevalence of looping of the IAN was retrospectively determined to assess the need for imaging prior to implant placement in the anterior mandible. MATERIALS AND METHODS: Cone beam computed tomography scans of consecutive patients were evaluated to assess the prevalence and size of IAN looping. The results were compared with respect to patient age and sex as well as degree of atrophy and bone height at the mental foramen. RESULTS: Scans of 1,010 patients were obtained. IAN loops were found in 31% of the patients, with a significantly higher prevalence in male patients (33.1%) than in female patients (28.1%). The average size of loops was 1.4 ± 0.70 mm, with a maximum of 4.6 mm. For male patients, the average loop size was 1.6 ± 0.74 mm (maximum 4.6 mm), and for female patients an average dimension of 1.4 ± 0.63 mm (maximum 4.4 mm) was recorded. This difference was significant (t test). A significant difference with respect to the various classes of atrophy up to class 4 was not found. CONCLUSION: Loops of the IAN occur in about one third of patients and vary in size from 0.7 to 4.6 mm. Large anterior loops put the IAN at risk when interforaminal implants are placed. Either a sufficient safety distance or three-dimensional imaging procedures should be used to detect loops and locate the incisive canal, which could be harmed during the interforaminal implant placement.

Accuracy of a newly developed open-source system for dental implant planning.

PURPOSE: To evaluate the accuracy of a newly developed open-source system for three-dimensional dental implant planning and fully guided dental implant placement. MATERIALS AND METHODS: Forty-eight implant positions were planned for eight partially edentulous anatomical patient equivalent models with an open-source implant planning system on the basis of cone beam computed tomography (CBCT) scans. The virtual software planning leads to an output of four different coordinates for each implant position; with these, surgical guides were manufactured using a coordinate-transfer apparatus. During the surgical simulation, drills and implants were fully guided as they were inserted by means of the harmonized components of the vendor's sleeve-in-sleeve system. After follow-up CBCT investigation and reference marker-based software registration, linear horizontal, vertical, and maximal 3D deviations, as well as angular deviations, between the virtual planning data and the surgical results were calculated. RESULTS: The mean three-dimensional deviation values for the final implant positions were 671 µm (95% confidence interval [CI] 452 to 891 µm) at the implant base and 808 µm (95% CI 646 to 971 µm) at the implant tip. Mean vertical deviations were 273 µm (95% CI 200 to 345 µm). Mean angular deviations of 1.9 degrees (95% CI 1.4 to 2.4 degrees) were measured. CONCLUSIONS: The open-source implant planning system described in this study demonstrated a level of accuracy that is equal or superior to most descriptions of the literature on computer-aided implant dentistry, allows for predictable implant positioning, and has the potential to reduce postoperative impairment versus conventional implant insertion.

Biocompatibility and biodegradation of a native porcine pericardium membrane: results of in vitro and in vivo examinations.

PURPOSE: The principle of guided tissue and bone regeneration has long been established for treating bone and periodontal defects. In addition to nonabsorbable barriers, various collagens have become accepted as membrane materials for separating the graft from soft tissue. However, collagen membranes differ significantly in their barrier function and biocompatibility. The objective of this pilot study was to examine, in vitro and in vivo, a novel native collagen membrane extracted from porcine pericardium. MATERIALS AND METHODS: The morphologic structure of two different native collagen membranes (Remotis, Thommen Medical; Bio-Gide, Geistlich Biomaterials) was examined using a scanning electron microscope. For biocompatibility testing, membranes were incubated with SaOs-2 osteoblastlike cells. After 2 hours, 3 days, and 7 days, proliferation of the cells on the membranes was determined. Evaluation of the biodegradation pattern was performed in a dog model with simultaneous bone augmentation with Bio-Oss (Geistlich Biomaterials) or Cerabone (Botiss Biomaterials) in the lateral anterior maxilla in eight animals with histologic examination after 4, 8, 12, and 24 weeks. RESULTS: An interconnective pore system was identifiable for Remotis, while Bio-Gide displayed a more fibrous structure. In vitro, Remotis showed considerable cell proliferation, which was significantly superior to that observed with Bio-Gide, especially after 7 days (2,910 ± 1,273 and 707 ± 706, respectively). In vivo, both membranes integrated into the surrounding tissue without any inflammatory reaction. Both membranes allowed early vascularization. However, considerable biodegradation was noted within 4 to 8 weeks with Bio-Gide, while Remotis resorbed generally within the first 8 to 12 week. Both membranes supported underlying bone formation. CONCLUSION: Both examined membranes indicate a high level of biocompatibility. Both are resorbed without inflammation within 8 weeks (Bio-Gide) or 12 weeks (Remotis). The compact interconnective pericardium collagen of Remotis may have stabilized the resorption process.

A comparison of multislice computerized tomography, cone-beam computerized tomography, and single photon emission computerized tomography for the assessment of bone invasion by oral malignancies.

OBJECTIVE: The aim of this study was to compare the performance of cone-beam computerized tomography (CBCT) with multislice CT (MSCT) and single photon emission CT (SPECT) in the detection of bone invasion from oral malignancies. STUDY DESIGN: In this prospective investigation, 77 patients with histologically proven malignancy of the oral cavity received MSCT, CBCT, and SPECT imaging of the head presurgically. Radiologic evaluations were compared with histopathologic examinations of the resected tumor specimens. Receiver operating characteristic (ROC) analysis as well as the sensitivity, specificity, and positive and negative predictive values were calculated. RESULTS: The sensitivity, specificity, positive predictive value, and negative predictive value for MSCT were 0.8, 1.0, 1.0, and 0.75, respectively; for CBCT 0.92, 0.965, 0.98, and 0.875; and for SPECT 0.91, 0.4, 0.7, and 0.75. ROC analysis showed area under the curve values of 0.894 (95% confidence interval [CI] 0.806-0.982) for MSCT; 0.931 (95% CI 0.835-1.000) for CBCT, and 0.716 (95% CI 0.566-0.866) for SPECT. CONCLUSION: CBCT is accurate in predicting malignancies' bone involvement and can compete with MSCT and SPECT in detecting bone invasion in patients with oral malignancies.