Automated 3-D Computer-Aided Measurement of the Bony Orbit: Evaluation of Correlations among Volume, Depth, and Surface Area.

(1)The study aimed to measure the depth, volume, and surface area of the intact human orbit by applying an automated method of CT segmentation and to evaluate correlations among depth, volume, and surface area. Additionally, the relative increases in volume and surface area in proportion to the diagonal of the orbit were assessed. (2) CT data from 174 patients were analyzed. A ball-shaped mesh consisting of tetrahedral elements was inserted inside orbits until it encountered the bony boundaries. Orbital volume, area depth, and their correlations were measured. For the validation, an ICC was used. (3) The differences between genders were significant (p < 10-7) but there were no differences between sides. When comparing orbit from larger to smaller, a paired sample t-test indicated a significant difference in groups (p < 10-10). A simple linear model (Volume~1 + Gender + Depth + Gender:Depth) revealed that only depth had a significant effect on volume (p < 10-19). The ICCs were 1.0. (4) Orbital volume, depth, and surface area measurements based on an automated CT segmentation algorithm demonstrated high repeatability and reliability. Male orbits were always larger on average by 14%. There were no differences between the sides. The volume and surface area ratio did not differ between genders and was approximately 0.75.

Combination of Rigid and Nonrigid Fixation Versus Nonrigid Fixation for Bilateral Mandibular Fractures: A Multicenter Randomized Controlled Trial.

PURPOSE: We aimed to compare complication rates and functional outcomes in patients with bilateral mandibular fractures treated with different degrees of internal fixation rigidity. PATIENTS AND METHODS: This international, multicenter randomized controlled trial included adults with bilateral mandibular fractures located at either the angle and body, angle and symphysis, or body and symphysis. Patients were treated with either a combination of rigid fixation for the anterior fracture and nonrigid fixation for the posterior fracture (mixed fixation) or nonrigid fixation for both fractures. The primary outcome was complications within 6 weeks after surgery. Secondary outcomes were complications within 3 months, Helkimo dysfunction index, and mandibular mobility at 6 weeks and 3 months after surgery. RESULTS: Of the 315 patients enrolled, 158 were randomized to the mixed fixation group and 157 to the nonrigid fixation group. The overall complication rate at 6 weeks in the intention-to-treat population was 9.6% (95% confidence interval [CI], 5.3% to 15.6%) in the mixed fixation group and 7.8% (95% CI, 4.0% to 13.5%) in the nonrigid fixation group. With an unadjusted odds ratio of 1.25 (95% CI, 0.51 to 3.17), there were no statistically significant differences in complication rates between the 2 groups (P = .591). A multivariable model for complication risk at 6 weeks found no significant differences between treatment groups, but patients with moderate or severe displacement had a higher complication rate than those with no or minimal displacement (adjusted odds ratio, 4.58; 95% CI, 1.16 to 18.06; P = .030). There were no significant between-group differences in complication rates at 3 months. Moreover, no significant differences in Helkimo dysfunction index and mandibular mobility index at 6 weeks and 3 months were found between groups according to treatment allocated and treatment received. CONCLUSIONS: A combination of rigid and nonrigid fixation in patients with bilateral mandibular fracture has similar complication rates and functional outcomes to nonrigid fixation for both fractures.

The Comprehensive AO CMF Classification System for Mandibular Fractures: A Multicenter Validation Study.

The AO CMF has recently launched the first comprehensive classification system for craniomaxillofacial (CMF) fractures. The AO CMF classification system uses a hierarchical framework with three levels of growing complexity (levels 1, 2, and 3). Level 1 of the system identifies the presence of fractures in four anatomic areas (mandible, midface, skull base, and cranial vault). Level 2 variables describe the location of the fractures within those defined areas. Level 3 variables describe details of fracture morphology such as fragmentation, displacement, and dislocation. This multiplanar radiographic image-based AO CMF trauma classification system is constantly evolving and beginning to enter worldwide application. A validation of the system is mandatory prior to a reliable communication and data processing in clinical and research environments. This interobserver reliability and accuracy study is aiming to validate the three current modules of the AO CMF classification system for mandible trauma in adults. To assess the performance of the system at the different precision levels, it focuses on the fracture location within the mandibular regions and condylar process subregions as core components giving only secondary attention to morphologic variables. A total of 15 subjects individually assigned the location and features of mandibular fractures in 200 CT scans using the AO CMF classification system. The results of these ratings were then statistically evaluated for interobserver reliability by Fleiss' kappa and accuracy by percentage agreement with an experienced reference assessor. The scores were used to determine if the variables of levels 2 and 3 were appropriate tools for valid classification. Interobserver reliability and accuracy were compared by hierarchy of variables (level 2 vs. level 3), by anatomical region and subregion, and by assessor experience level using Kruskal-Wallis and Wilcoxon's rank-sum tests. The AO CMF classification system was determined to be reliable and accurate for classifying mandibular fractures for most levels 2 and 3 variables. Level 2 variables had significantly higher interobserver reliability than level 3 variables (median kappa: 0.69 vs. 0.59, p < 0.001) as well as higher accuracy (median agreement: 94 vs. 91%, p < 0.001). Accuracy was adequate for most variables, but lower reliability was observed for condylar head fractures, fragmentation of condylar neck fractures, displacement types and direction of the condylar process overall, as well as the condylar neck and base fractures. Assessors with more clinical experience demonstrated higher reliability (median kappa high experience 0.66 vs. medium 0.59 vs. low 0.48, p < 0.001). Assessors with experience using the classification software also had higher reliability than their less experienced counterparts (median kappa: 0.76 vs. 0.57, p < 0.001). At present, the AO CMF classification system for mandibular fractures is suited for both clinical and research settings for level 2 variables. Accuracy and reliability decrease for level 3 variables specifically concerning fractures and displacement of condylar process fractures. This will require further investigation into why these fractures were characterized unreliably, which would guide modifications of the system and future instructions for its usage.

Regeneration of Cystic Bone Cavities and Bone Defects With Bioactive Glass S53P4 in the Upper and Lower Jaws.

Cysts and tumors are common lesions in the jaws. To be able to retain a good volume of the alveolar ridge during healing as well as strengthening the angle and body of the mandible and provide an instant improved support for adjacent teeth, reliable long-term bone regeneration is needed. The purpose of this prospective study was to promote bone regeneration by filling bony defects in the upper or lower jaw with granules of the bioactive glass S53P4 (BAG), which have osteostimulative and antimicrobial properties.The authors treated 20 patients (21 defects) surgically; benign tumors, cysts, or infection related to impacted teeth in the maxilla or mandible. The tumor or cyst was removed or enucleated and thorough cleaning of the infected area was performed. The bone cavity was filled with granules of the BAG S53P4 despite signs of chronic infection in the area at the time of surgery. The patients were followed up for an average of 34 months clinically and with cone beam computerized tomography for 28 months. In 20 defects the final outcome was successful. Despite infection at the time of surgery in 65% of the patients, no material associated infection was seen during the follow-up. The BAG S53P4 granules were radiologically remodeled into bone after 2 years follow-up. The use of granules of the BAG S53P4 in the treatment of large bone defects provides infection-free reliable bone regeneration despite chronic infection at the time of surgery, which improves the prognosis of adjacent teeth.

Rapid prototyped patient specific guiding implants in critical mandibular reconstruction.

Large tumours of the mandible need immediate reconstruction to provide continuity of the mandible, satisfactory function of the jaw, as well as an acceptable aesthetic outcome. In this prospective study we described the immediate reconstruction of the mandible using computer aided design and 15 rapid prototyped patient specific implants (PSI) in 14 patients suffering from benign or malignant tumours demanding continuity resection of the mandible. The scaffold PSI was filled with ß-tricalcium phosphate granules and autologous bone. Microvascular reconstruction was additionally needed in 12/15 cases. The clinical follow up was on average 33 months and the radiological follow up was on average 21 months. In nine cases the healing was uneventful. One patient lost the microvascular flap during the first postoperative week and one patient needed a revision due to perforation of the mucosa at the site of the PSI. Four patients had a major complication due to perforation of the mucosa leading to infection, which resulted in the total or partial removal of the PSI. The PSI seems to be a promising solution for treatment of patients demanding large reconstruction after mandible resection. The benefits are decreased rate of donor site complications and more accurate and prompt surgical procedure.

Multidisciplinary Approach to Management of Temporal Bone Giant Cell Tumor.

Background Giant cell tumors (GCTs) are rare osseous tumors that rarely appear in the skull. Methods We review the clinical course of a 28-year-old previously healthy woman with a complicated GCT. Results The reviewed patient presented with a middle cranial fossa tumor acutely complicated by reactive mastoiditis. Left tympanomastoidectomy was performed for drainage of the mastoiditis and for biopsies of the tumor. Due to the challenging tumor location, the patient was treated with denosumab, a fully humanized monoclonal antibody against receptor activator of nuclear factor kappa-B ligand, for 7 months, which resulted in significant preoperative tumor shrinkage. Extensive temporal craniotomy and resection of the tumor followed utilizing a temporomandibular joint total endoprosthesis for reconstruction. A recurrence of the tumor was detected on computed tomography at 19 months after surgery and treated with transtemporal tumor resection, parotidectomy, and mandible re-reconstruction. Conclusion A multidisciplinary approach resulted in a good functional result and, finally, an eradication of the challengingly located middle cranial fossa tumor.

Rapid prototyping modelling in oral and maxillofacial surgery: A two year retrospective study.

BACKGROUND: The use of rapid prototyping (RP) models in medicine to construct bony models is increasing. MATERIAL AND METHODS: The aim of the study was to evaluate retrospectively the indication for the use of RP models in oral and maxillofacial surgery at Helsinki University Central Hospital during 2009-2010. Also, the used computed tomography (CT) examination - multislice CT (MSCT) or cone beam CT (CBCT) - method was evaluated. RESULTS: In total 114 RP models were fabricated for 102 patients. The mean age of the patients at the time of the production of the model was 50.4 years. The indications for the modelling included malignant lesions (29%), secondary reconstruction (25%), prosthodontic treatment (22%), orthognathic surgery or asymmetry (13%), benign lesions (8%), and TMJ disorders (4%). MSCT examination was used in 92 and CBCT examination in 22 cases. Most of the models (75%) were conventional hard tissue models. Models with colored tumour or other structure(s) of interest were ordered in 24%. Two out of the 114 models were soft tissue models. CONCLUSIONS: The main benefit of the models was in treatment planning and in connection with the production of pre-bent plates or custom made implants. The RP models both facilitate and improve treatment planning and intraoperative efficiency. KEY WORDS: Rapid prototyping, radiology, computed tomography, cone beam computed tomography.

Imaging characteristics of ameloblastomas and diagnostic value of computed tomography and magnetic resonance imaging in a series of 26 patients.

OBJECTIVES: To evaluate the imaging characteristics of ameloblastomas and to analyze the diagnostic value of computed tomography (CT) and magnetic resonance imaging (MRI) compared with conventional dentoalveolar imaging. STUDY DESIGN: In this observational retrospective study, the panoramic radiographs (n = 25) and the CT (n = 26) and MRI (n = 5) images of histopathologically verified ameloblastomas in 26 patients were reviewed. RESULTS: Characteristic findings were multilocularity, marked expansion of the cortical plate, perforation at an earlier stage, and extensive root resorption. On contrast-enhanced CT or MRI, the majority (14 of 17) of the nonunicystic ameloblastomas contained a mixed cystic and solid pattern. Unicystic ameloblastomas (n = 6) and ameloblastomas derived from the cyst epithelium (n = 2) showed thick rim enhancement or a mural solid component in an otherwise cystic lesion. CONCLUSIONS: Contrast-enhanced CT and MRI greatly aid in distinguishing between ameloblastomas and other cystlike lesions because they allow for visualization of the mixed cystic and solid content characteristic of nonunicystic ameloblastomas. The differential diagnostic value of CT and MRI is significant with regard to unicystic ameloblastomas.

The use of anatomically drop-shaped bioactive glass S53P4 implants in the reconstruction of orbital floor fractures--A prospective long-term follow-up study.

An isolated fracture of the orbital floor needs reconstruction if there is a clear herniation of adipose tissue or of the rectus inferior muscle into the maxillary sinus. A prospective study was carried out treating 20 patients with an isolated blow-out fracture of the orbital floor or with a combined zygomatico-orbito-maxillary complex fracture, using a newly designed anatomically drop-shaped implants made of bioactive glass (BAG) S53P4. Computed tomography (CT) was performed immediately postoperatively to confirm the correct position of the plate. The patients were followed up for an average of 32 months clinically and radiologically with magnetic resonance imaging (MRI) for an average of 31 months. None of the patients had any signs of complications related to the implant and the clinical outcome was very good. None of the patients had persisting diplopia. The level of the pupillas was normal in 15 of 20 patients. Minor hypo-ophthalmos ranging from 0.5 to 1.0 mm was observed in three patients, and moderate hypo-ophthalmos of 2.0 mm was seen in one patient. Hyperophthalmos of 1.0 mm was seen in one patient. Minor enophthalmos on the operated side ranging from 0.5 to 1.0 mm was seen in eight patients. Mild to moderate paraesthesia of the infraorbital nerve was observed in six patients. The immediate postoperative CT and the long term follow-up MRI revealed that the drop-shaped BAG implants retained their correct position in the orbital floor and did not show any evidence of losing their original shape or material resorption. No adverse tissue reaction was associated with the material. Due to the anatomical drop shape, the implants could successfully maintain the orbital volume and compensate for the retrobulbar adipose tissue atrophy.

MMP-7, MMP-8, and MMP-9 in oral and cutaneous squamous cell carcinomas.

OBJECTIVES: Oral squamous cell carcinoma (OSCC) and cutaneous squamous cell carcinoma (CSCC) are epithelial neoplasms, of which OSCC has a worse prognosis. Matrix metalloproteinases (MMPs) are involved in the initiation, invasion, metastasis, and defense of cancer. This study aimed to compare differences in MMP expression in these cancers. STUDY DESIGN: Sixty-one patients with early-stage (T1-T2 N0 M0) cancers, of which 36 were OSCC and 25 CSCC, were enrolled into this study. Immunohistochemical staining was performed with MMP-7, MMP-8, and MMP-9 antibodies. RESULTS: MMP-7 expression was stronger in OSCC than in CSCC, mainly in the invasive front. MMP-8 was absent and MMP-9 was mildly expressed in OSCC and CSCC cells. However, MMP-8 and MMP-9 were positive in peritumoral inflammatory cells in both cancers. In addition, MMP-7, MMP-8, and MMP-9 were not associated with the overall survival of patients with OSCC and CSCC patients. CONCLUSIONS: The increased expression of MMP-7 in the invasive front may partly explain the aggressiveness of OSCC.

Toll-like receptors -4 and -5 in oral and cutaneous squamous cell carcinomas.

BACKGROUND: Oral squamous cell carcinoma (OSCC) has a worse prognosis than cutaneous squamous cell carcinoma (CSCC). Toll-like receptor- 4 (TLR-4) and TLR-5 are transmembrane proteins that recognize endogenous and microbial agents. Their activation has been connected to cancer invasion. OBJECTIVE: The aim was to study the expression of TLR-4 and TLR-5 in OSCC and CSCC samples, and the effects of TLR-5 ligand flagellin on the proliferation, migration, and invasion of different mucocutaneous cell lines in vitro. METHODS: Samples of early-stage tumors (T1-T2N0M0) from 63 patients with OSCC and CSCC were obtained, in addition to eight normal mucosa and skin tissues from healthy subjects. Oral-cavity-derived highly aggressive HSC-3, less invasive SAS, and HPV-transformed benign IHGK as well as C-ha-ras-transformed (HaCat) skin carcinoma II-4 and non-invasive A5 cell lines were used. Flagellin-induced mucocutaneous cell lines were compared by using BrdU-proliferation, scratch migration, and myoma organotypic invasion assays. RESULTS: TLR-4 expression was similar in OSCC and CSCC tumors. TLR-5 was more abundant in OSCC than in CSCC samples. Flagellin induced the proliferation of SAS, II-4 and A5, migration of IHGK, II-4 and A5, and the invasion of II-4 cells. It had no effect on HSC-3 cells. CONCLUSIONS: Flagellin, a TLR-5 agonist, induced the migration and invasion of less aggressive mucocutaneous cell lines, but it had no effect on the most invasive oral carcinoma cells. The more aggressive clinical behavior of OSCC compared to CSCC may partially be related to the differences in the expression of TLR-5 in these malignancies.

Rapid prototyped patient specific implants for reconstruction of orbital wall defects.

Defects of orbital walls can be reconstructed using implants. The authors report a safe and accurate method to reconstruct bone defects in the orbital area using patient specific implants. A detailed process description of computer aided design (CAD) reconstructive surgery (CRS) is introduced in this prospective study. The 3D volumetric virtual implant was design using MSCT data and PTCProEngineer™ 3D software. The intact orbital cavity of twelve patients was mirrored to the injured side. Specific ledges steered the implant into correct place. Postoperatively the position was assessed using image fusion. One implant (8%) was rejected due to chemical impurities, two (16%) had a false shape due to incorrect CAD. Data of thin bone did not transfer correctly to CAD and resulted in error. One implant (8%) was placed incorrectly. Duration of the CRS was in average 1.17 h, correspondingly 1.57 h using intraoperative bending technique. The CRS process has several critical stages, which are related to converting data and to incompatibility between software. The CRS process has several steps that need further studies. The data of thin bone may be lost and disturb an otherwise very precise technique. The risk of incorporating impurities into the implant must be carefully controlled.

Update on mandibular reconstruction: computer-aided design, imaging, stem cells and future applications.

PURPOSE OF REVIEW: The development of three-dimensional (3D) computerized modelling has been rapid during the last years. The computer technology in addition to computer-aided manufacturing (CAM) has given tools for surgeons to plan, practice virtually the surgery and to design and manufacture the implants needed for the surgery. RECENT FINDINGS: Bone tissue regeneration seems to be dependent on several critical factors. These include biocompatible patient-specific scaffolds and matrices, osteogenic cells and osteoinductive and angioinductive growth factors. At present, modern 3D computer-aided design (CAD) software and additive manufacturing technology enable patient-specific scaffold and matrix manufacturing. The scaffold, matrix or implant replaces the missing part of the jaw and allows osteogenic cells to generate bone accordingly and allows anatomic and symmetrical restoration. An increasing number of studies, both experimental and clinical, have been published that show bone formation in mandible defects after reconstruction with matrix-osteogenic cell combination. Ideally, matrix (bone substitute material) should be biocompatible, bioresorbable, osteoconductive, osteoinductive, structurally similar to bone, easy to use, cost-effective and nonanimal derived. SUMMARY: It is still unknown which type of osteogenic cell is the most efficient. Are added cells in bone regeneration process necessary? One of the crucial issues is the vascularization of forming ectopic bone. More studies are needed on how to generate adequate vascularization for the survival of cells and formation of bone. Further studies are also needed to find more and better materials for additive manufacturing (CAD-CAM) of scaffolds, matrices and implants.

A novel classification and online platform for planning and documentation of medical applications of additive manufacturing.

Additive manufacturing technologies are widely used in industrial settings and now increasingly also in several areas of medicine. Various techniques and numerous types of materials are used for these applications. There is a clear need to unify and harmonize the patterns of their use worldwide. We present a 5-class system to aid planning of these applications and related scientific work as well as communication between various actors involved in this field. An online, matrix-based platform and a database were developed for planning and documentation of various solutions. This platform will help the medical community to structurally develop both research innovations and clinical applications of additive manufacturing. The online platform can be accessed through http://www.medicalam.info.

Epithelial and stromal syndecan-1 and -2 are distinctly expressed in oral- and cutaneous squamous cell carcinomas.

BACKGROUND: Oral squamous cell carcinoma (OSCC) and cutaneous squamous cell carcinoma (CSCC) are epithelial neoplasms of which OSCC has worse survival and higher risk of metastasis than CSCC. The aim of this study was to explore the differences of immunoexpressions between syndecan-1 and -2 in OSCC and head and neck CSCC. METHODS: A total of 35 patients diagnosed with OSCC and 25 with CSCC, presented T1 and T2 tumors and treated at Helsinki University Central Hospital between years 2001 and 2009, were selected into this study. The levels and locations of syndecan-1 and -2 immunostainings were analyzed using formalin-fixed and paraffin-embedded tissue samples of OSCC and CSCC cases together with clinical data. RESULTS: Cell membrane epithelial syndecan-1 expression decreased significantly compared to normal tissue in both cancer types. Cell membrane syndecan-1 expression in the invasive front had negative correlation with invasion depth of both tumors (OSCC, r = -0.339, P = 0.025; CSCC, r = -0.469, P = 0.004). In cancers over 4-mm invasion depth, the number of stromal syndecan-1-positive collagen fibers and inflammatory cells were higher in OSCC than in CSCC. Syndecan-2 expression in non-malignant stroma was higher in CSCC than in OSCC tumors. In addition, unlike syndecan-1, syndecan-2 was more often and more intensively expressed in the tumor inflammatory cells in CSCC than in OSCC. CONCLUSION: Our results suggest that variable stromal expression of syndecan-1 and -2 in OSCC compared to CSCC may at least partially explain the differences in their clinical behavior.

[Head and neck reconstructions]. / Pään ja kaulan alueen rekonstruktiot.

Tissue reconstructions of the head and neck are required both in the repair of tissue defects following the surgical excision of malignant tumors and in the treatment of various other facial deformities. While it is usually possible to repair a damaged tissue or organ region, functional restoration is very difficult. The aim is radical excision of the tumor, and successful reconstruction will provide quality of life for the patient even after an extensive surgical procedure. The goal of the new reconstructive procedures is as natural outcome as possible, but the risk for postoperative complications must be taken into account.

[Therapeutic results in oral cancer--what has been learned?]. / Suusyövän hoitotulokset--mitä on opittu?

Oral cancer is the most common head and neck cancer in Finland. The number of new cases has been on a steady rise over the last decades. Smoking and heavy drinking are the most important risk factors. The role of papilloma virus infection is under active research, albeit with a smaller role than in oropharyngeal cancer, for instance. Surgical excision of the tumor is usually the first-line treatment. Pathoanatomical investigation of the primary tumor and cervical lymph nodes is essential in evaluating the need of adjuvant therapy. The prognosis of oral cancer has improved as a result of early detection and development of treatment modalities.

Mandibular osteomyelitis in children mimicking juvenile recurrent parotitis.

OBJECTIVE: To describe pediatric cases with mandibular osteomyelitis initially diagnosed and treated as juvenile recurrent parotitis. METHODS: We reviewed the patient data of all our pediatric patients treated at Helsinki University Central Hospital, a tertiary care hospital, between 1998 and 2010 who had the initial diagnosis of recurrent parotitis which in fact was osteomyelitis. RESULTS: Over a period of 12 years, six children (aged 5-17 years, five girls) presented with mandibular osteomyelitis primarily diagnosed as recurrent parotitis. Diagnostic delay ranged from 1.5 months to 6.0 years before the final diagnosis of mandibular osteomyelitis confirmed in MRI. Of the six cases undergoing biopsies, bacterial culture showed Actinomyces or Streptococcus viridans in four cases. All patients received antimicrobial treatment. Two received hyperbaric oxygen therapy with no resolution of symptoms. Debridement was performed in these two cases as well, and in the second case persistent symptoms led to bisphosphonate treatment. CONCLUSIONS: Juvenile parotitis is in most cases a clinical diagnosis, and treatment is symptomatic. In contrast, mandibular osteomyelitis is a severe disease requiring lengthy treatment. Because symptoms of these two entities may mimic each other, unclear cases require MRI.

[Reconstruction of the oral cavity and the maxillomandibular region]. / Suuontelon ja leukojen alueen rekonstruktiot.

Traumas, tumors, congenital malformations and infections of the face and the jaws may give rise to extensive tissue defects, causing esthetic disfigurement requiring challenging reconstruction. Facial and jaw defects can be repaired with various local tissue grafts. Free bone grafts can be used alone or combined with pedunculated grafts. Free tissue grafts can be taken that contain merely the skin and the subcutaneous fat, or they can be combined with bone, muscle, or a combination of these.