Obstacles in spatial evaluation of CBCT-reformatted panoramic imaging.

OBJECTIVES: Conventional panoramic radiography (cPR) underlines procedure-related limitations in the display of objects. CBCT is presumed to overcome these constraints. To virtualize a cPR view, reformatted panoramic images (rPIs) can be generated. This study evaluated the rPI with regard to its susceptibility to sterical object deposition in comparison with cPR. METHODS: A specially developed implant model with dental implants each of 4.0-mm diameter and 11.0-mm length was depositioned by shift, rotation and tilt of 5.00 mm (±0.01 mm) of horizontal shift and 5.0° (±0.167°), respectively, on a highly precise goniometer rotation table, and cPRs and rPIs were generated. Automated evaluation of the cPRs was carried out using a specially developed software. rPIs were processed and analyzed by a semi-automated image analysis. RESULTS: Object deposition lead to distortive effects in the rPI analogue to cPR, but they appear in display only. Objects illustrated in the rPI were dimensionally correct, but sterical relations are elusive. Results are obtained for the horizontal shift, declination and reclination, lateral tilt and rotation. CONCLUSIONS: Distortions within the rPI represent the illustration of the hyperbolic-shaped layer out of the three-dimensional data set. With this study, we demonstrated these procedure-related inherent but practically underestimated consequences. Effects of sterical object malpositioning must be compensated by the observer by adequate virtual adjustment of the processed layer. Accurate virtual adjustment leads to vertical dimensions. Sterical relations, e.g. angulation of two objects, are irretraceable unless precisely referenced.

Prospective biomechanical analysis of donor-site morbidity after fibula free flap.

PURPOSE: The fibula free flap (FFF) is a standard method for osseous reconstruction. The purpose of this study was to investigate functional deficits after harvesting a free fibula flap. MATERIAL AND METHODS: We designed and implemented a prospective clinical cohort study. The study sample consisted of patients undergoing mandible resection and reconstruction with a fibula free flap. The primary endpoint was the time-dependent difference in maximum peak power per body mass (MPP). In addition, balance ability, American Orthopedic Foot and Ankle Society (AOFAS) score, sensory limitations, general surgical complications, and the range of motion were recorded. RESULTS: A total of 27 patients were examined pre- and postoperatively (8 months on average). MPP and balance ability were significantly reduced (p < 0.001) postoperatively. Furthermore, a deficit in dorsal extension and a considerable reduction of the AOFAS score were recorded. For the primary outcome, there were no significant predictors on multivariate analysis. CONCLUSIONS: Our results indicate a postoperative reduction of lower limb performance with a relevant impact on everyday activities, equivalent to the average loss of 7 life years of a healthy, fit individual. However, these data do not challenge the value of this commonly used microvascular graft. Future efforts should focus on the development of strategies to minimize the associated donor-site morbidity.

Prospective biomechanical evaluation of donor site morbidity after radial forearm free flap.

Although the radial forearm free flap (RFF) is a commonly-used microvascular flap for orofacial reconstruction, we are aware of few prospective biomechanical studies of the donor site. We have therefore evaluated the donor site morbidity biomechanically of 30 consecutive RFF for orofacial reconstruction preoperatively and three months postoperatively. This included the Mayo wrist score, the Disabilities of the Arm, Shoulder and Hand (DASH) score, grip strength, followed by tip pinch, key pinch, palmar pinch, and range of movement of the wrist. Primary defects were all closed with local full-thickness skin grafts from the donor site forearm, thereby circumventing the need for a second defect. Postoperative functional results showed that there was a reduction in hand strength measured by (grip strength: -24.1%, in tip pinch: -23.3%, in key pinch: -16.5, and in palmar pinch: -19.3%); and wrist movement measured by extension (active=14.3% / passive= -11.5%) and flexion = -14.8% / -8.9%), and radial (-9.8% / -9.8%) and ulnar (-11.0% / -9.3%) abduction. The Mayo wrist score was reduced by 9.4 points (-12.9%) and the DASH score increased by 16.1 points (+35.5%) compared with the same forearm preoperatively. The local skin graft resulted in a robust wound cover with a good functional result. Our results show that the reduction in hand strength and wrist movement after harvest of a RFF is objectively evaluable, and did not reflect the subjectively noticed extent and restrictions in activities of daily living. Use of a local skin graft avoids a second donor site and the disadvantages of a split-thickness skin graft.

Linear accuracy and reliability of volume data sets acquired by two CBCT-devices and an MSCT using virtual models: a comparative in-vitro study.

OBJECTIVE: To discriminate clinically relevant aberrance, the accuracy of linear measurements in three-dimensional (3D) reconstructed datasets was investigated. MATERIALS AND METHODS: Three partly edentulous human skulls were examined. Landmarks were defined prior to acquisition. Two CBCT-scanners and a Quad-slice CT-scanner were used. Actual distances were physically measured with calipers and defined as a reference. Subsequently, from digital DICOM datasets, 3D virtual models were generated using maximum intensity projections (MIPs). Linear measurements were performed by semi-automated image analysis. Virtual and analogue linear measurements were compared using repeated measurements in a mixed model (p ≤ 0.05). RESULTS: No significant difference was found among all of the digital measurements when compared to one another, whereas a significant difference was found in matched-pairs analysis between CBCT and calipers (p = 0.032). All digitally acquired data resulted in lower mean values compared to the measurements via calipers. A high level of inter-observer reliability was obtained in the digital measurements (inter-rater correlation = 0.988-0.993). CONCLUSIONS: The reconstructed datasets led to highly consistent values among linear measurements. Yielding sub-millimeter precision, these modalities are assumed to reflect reality in a clinically irrelevant altered manner. During data acquisition and evaluation, a maximum of precision must be achieved.

Long-term biomechanical analysis of donor site morbidity after radial forearm free flap.

BACKGROUND: Although the radial forearm free flap (RFF) is a commonly used microvascular graft for head and neck reconstruction, long-term biomechanical results regarding donor site morbidity are rare. PATIENTS AND METHODS: In a prospective panel study, 32 patients were included. Biomechanical assessment was performed preoperatively, three months postoperatively and two years postoperatively. The primary endpoint of the study was grip strength. In addition, the Mayo wrist score, DASH score (disabilities of the arm, shoulder and hand score), fine motor skill strengths (tip pinch, key pinch, palmar pinch) and the range of motion were analysed. Primary defects were closed with local full-thickness skin grafts (FTSG) from the donor site forearm avoiding a secondary defect site. RESULTS: In the long-term analysis, grip strength was reduced in both arms. A significant improvement over time was found only for the donor arm. A persistent deficit of tip pinch strength and dorsal extension was recorded. Persistent sensory limitations occurred in four cases. Patient contentment after two years of follow-up was high and daily life routine was not restricted. CONCLUSION: Gross and fine motor skill limitations are reversible short-term effects after RFF harvesting and do not restrict daily routine in the long term. These findings substantiate the value of the RFF as a workhorse in reconstructive surgery.

Thromboelastometry: A contribution to perioperative free-flap management.

BACKGROUND: Microvascular tissue transfer is a fundamental part of reconstructive surgery. Different perioperative anticoagulation regimens exist, influencing hemostatic parameters. Since bleeding and thrombosis are major reasons for revision procedures and flap loss, current practice regarding anticoagulative treatment needs further refinement. Thromboelastometry has been demonstrated as worthwhile in the determination of alterations of the anticoagulation cascade. We evaluated this aspect of thromboelastometry for free flap surgery. METHODS: Thirty-five patients undergoing free-flap surgery were enrolled in this study. Blood samples were obtained at three time points: at the beginning of surgery, at time of anastomosis and after 24 h. At each time point, thromboelastometry with special regard to clotting times for the intrinsic and extrinsic paths of coagulation was immediately performed. Global coagulation markers and clinical parameters were collected simultaneously. RESULTS: Hemostatic changes were deducible using thromboelastometry perioperatively. Measured parameters differed significantly over time (p < 0.05). Heparin therapy showed a significant effect on the measured slope of INTEM-clotting times (p < 0.001). Altered values of thromboelastometry suggested non-inferiority to standard testing. Neither standard testing nor thromboelastometry were capable of predicting adverse events such as thrombosis, bleeding or flap loss (p > 0.05). CONCLUSIONS: Thromboelastometry monitors hemostatic effects almost in real-time and could serve as a supplementary tool in microvascular tissue transfer once its use has been standardized. The utilization of thromboelastometry allows for assessment of the anticoagulation needs of individual patients undergoing free flap surgery, which is frequently accompanied by hemostatic changes in the perioperative setting. Our findings implicate further validation of thromboelastometry in free-flap surgery.

Intraosseous heat generation during sonic, ultrasonic and conventional osteotomy.

OBJECTIVES: To assess heat generation in osteotomies during application of sonic and ultrasonic saws compared to conventional bur. METHODS: Two glass-fiber isolated nickel-chromium thermocouples, connected to a recording device, were inserted into fresh bovine rib bone blocks and kept in 20 ± 0.5 °C water at determined depths of 1.5 mm (cortical layer) and 7 mm (cancellous layer) and 1.0 mm away from the planned osteotomy site. Handpieces, angulated 24-32°, were mounted in a vertical drill stand, and standardized weights were attached to their tops to exert loads of 5, 8, 15 and 20 N. Irrigation volumes of 20, 50 and 80 ml/min were used for each load. Ten repetitions were conducted using new tips each time for each test condition. The Mann-Whitney-U test was used for statistical analysis (p < 0.05). RESULTS: Both ultrasonic and sonic osteotomies were associated with significantly lower heat generation than conventional osteotomy (p < 0.01). Sonic osteotomy showed non-significantly lower heat generation than ultrasonic osteotomy. Generated heat never exceeded the critical limit of 47 °C in any system. Variation of load had no effect on heat generation in both bone layers for all tested systems. An increased irrigation volume resulted in lower temperatures in both cortical and cancellous bone layers during all tested osteotomies. CONCLUSION: Although none of the systems under the conditions of the present study resulted in critical heat generation, the application of ultrasonic and sonic osteotomy systems was associated with lower heat generation compared to the conventional saw osteotomy. Copious irrigation seems to play a critical role in preventing heat generation in the osteotomy site.

Is immediate bony microsurgical reconstruction after head and neck tumor ablation associated with a higher rate of local recurrence?

The purpose of this retrospective study was to examine the possible effect of immediate bony microvascular free flap reconstruction of mandibular defects after radical tumor resection of oral squamous cell carcinoma (OSCC) on the rate of local relapse. Our own data regarding recurrence rates for 1-step immediate reconstruction were compared to the published recurrence rates of 2-step reconstructions. A total of 21 patients (aged 45-77 years) with OSCC who underwent a primary surgical therapy with subsequent immediate bony microvascular free flap reconstruction of mandibular defects were followed up for 18-38 months. Four local relapses (19%) were recorded, all in patients with initial tumor stage of T4. Although intraoperative histological findings were R0 in all 21 cases, definitive histology later detected R1 status in the resected bone in 2 cases (10%). Immediate bony free flap reconstruction of mandibular defects after radical surgical resection of OSCC does not seem to increase the risk of local recurrence nor affect patient survival when compared with the 2-step surgical approach.

Virtual planning of complex head and neck reconstruction results in satisfactory match between real outcomes and virtual models.

OBJECTIVES: The reconstruction of large facial bony defects using microvascular transplants requires extensive surgery to achieve full rehabilitation of form and function. The purpose of this study is to measure the agreement between virtual plans and the actual results of maxillofacial reconstruction. MATERIALS AND METHODS: This retrospective cohort study included 30 subjects receiving maxillofacial reconstruction with a preoperative virtual planning. Parameters including defect size, position, angle and volume of the transplanted segments were compared between the virtual plan and the real outcome using paired t test. RESULTS: A total of 63 bone segments were transplanted. The mean differences between the virtual planning and the postoperative situation were for the defect sizes 1.17 mm (95 % confidence interval (CI) (-.21 to 2.56 mm); p = 0.094), for the resection planes 1.69 mm (95 % CI (1.26-2.11); p = 0.033) and 10.16° (95 % CI (8.36°-11.96°); p < 0.001) and for the planes of the donor segments 10.81° (95 % CI (9.44°-12.17°); p < 0.001) The orientation of the segments differed by 6.68° (95 % CI (5.7°-7.66°); p < 0.001) from the virtual plan; the length of the segments differed by -0.12 mm (95 % CI (0.89-0.65 mm); not significant (n.s.)), respectively, while the volume differed by 73.3 % (95 % CI (69.4-77.6 %); p < 0.001). The distance between the transplanted segments and the remaining bone was 1.49 mm (95 % CI (1.24-1.74); p < 0.001) and between the segments 1.49 mm (95 % CI (1.16-1.81); p < 0.001). CONCLUSIONS: Virtual plans for mandibular and maxillofacial reconstruction can be realised with excellent match. CLINICAL RELEVANCE: These highly satisfactory postoperative results are the basis for an optimal functional and aesthetic reconstruction in a single surgical procedure. The technique should be further investigated in larger study populations and should be further improved.

Impact of malpositioning on panoramic radiography in implant dentistry.

OBJECTIVES: The widely used panoramic radiography as a special kind of tomography underlies intrinsic procedural restrictions such as poor definition, inconsistent magnification, geometric distortion and spatial depositioning of objects situated outside the focal trough. This results in a non-anatomic display of the radiographed anatomic structures. Individual mandibular angle and width of the jaws, adjustment of the focal trough, jaw incongruence as well as patient positioning increase the inconsistency in display of the radiographed objects. This study precisely evaluated the quantitative impact of object malpositioning on the display in panoramic radiography. MATERIALS AND METHODS: A special dental implant model was highly accurate three dimensionally malpositioned and panoramic radiographs were taken. Automated image analysis was performed to exclude subjective assessment error. RESULTS: Precise and retraceable object deposition of up to 5 mm or 5° resulted in relevant deposition of objects and significant changes in object size and inter-object distances in the panoramic image. Unidirectional malpositioning lead to multiple errors in display. CONCLUSIONS: The extent of malpositioning-related display errors additionally to the known physicotechnical insufficiencies of the panoramic radiography demonstrates its limitations in precisely interpreting spatial relationships. CLINICAL RELEVANCE: Measurements within the panoramic radiography must not claim reliability. For a single object securely positioned in the focal trough and perpendicular to the central X-ray beam, measurements may be trustworthy on clinical scale. Once sterical relationships to other structures are evaluated, reliability must be questioned.

Imaging of the midfacial and orbital trauma.

The severity of midfacial and orbital injuries depends on the one hand on cause, force vector, load point, or area and on the other hand on the bony and soft tissue resistance as well as individual anatomy. These variables result in a variety of possible injuries of the midfacial and orbital complex. The time critical choice of an adequate imaging modality of these injuries is influenced by the possible severity of concomitant injuries. Besides the confirmation of a clinical diagnosis, the need for high-resolution three-dimensional imaging for preoperative planning of facial reconstruction using intraoperative navigation has become more and more important in the past years. To achieve optimal functional and esthetic outcomes, the anatomical complexity of the midface has to be addressed and the adequate imaging modality has to be chosen keeping the upcoming surgical treatment in mind. The current imaging modalities for midfacial and orbital trauma are presented and critically evaluated depending on the indications. Furthermore, new strategies to support surgeons in achieving best possible midfacial reconstructions are discussed. An algorithm to choose the adequate imaging modality in midfacial and orbital traumatology is provided.

Evaluation of four different optimized magnetic-resonance-imaging sequences for visualization of dental and maxillo-mandibular structures at 3 T.

OBJECTIVES: The purpose of this study was to evaluate four in-house optimized, non-contrast enhanced sequences for MRI-investigation of maxillo-mandibular and dental structures by use of 3 T. METHODS: 12 volunteers with different dental status were examined by using a 3 T MRI with a 20-channel standard head-and-neck coil. All images performed were evaluated by using 3D-techniques, with different slice-thicknesses, in 3D T1- and T2-weighted sequences, as well as by using new techniques of image depictions. In addition phantom measurements were performed to estimate the extent of image artefacts caused by retainers and metal implants. RESULTS: Mean age of the participants was 33 years (range, 25.5-62.75 years), and the sex ratio was 5 females to 7 males. We identified different techniques to improve osseous and dental structures, despite problems caused by dental implants, tooth crowns or braces. CONCLUSION: The sequences evaluated offered excellent visualization in 2D and 3D of osseous and dental structures. Anatomical, osseous and dental structures were described at their ROI, in relation to patients with dental and head and neck pathologies. The ability to detect and distinguish pathological processes as soon as possible in 3D with excellent image quality avoiding ionizing radiation remains a challenging domain.

Outcome of microvascular free flaps in a high-volume training centre.

PURPOSE: Microvascular free tissue transfer allows major ablative defects following oncologic surgical and traumatic reasons to be reliably reconstructed in the head and neck region. A retrospective analysis of the microvascular flap procedures which were performed within one year in a high volume training centre was performed. PATIENTS AND METHODS: The microvascular free flap procedures of the year 2011 were reviewed and followed up until the 31st December 2012. The type and indication of the reconstructive procedure, operation time, operating team, experience and level of training of the surgeons involved, postoperative IMC (intermediate care unit) and/or ICU (intensive care unit) time, inpatient time, flap revisions, further postoperative complications, preoperative and postoperative radiation of the patients, the placement of dental implants were studied. RESULTS: From 1st of January 2011 to 31st of December, 2011, the data of 101 patients with 103 microvascular free flap procedures were analysed of which 72% (84 flaps) were harvested by residents. The patients ranged in age from 14 to 89 years (mean age 59 years, 71 males and 40 females). The mean operation time was 591 min with the longest operation times for scapular flaps (744 min) and the shortest operation times for ALT flaps (455 min). Mean inpatient time was 34.2 days with a minimal time for the fibular flaps of 27.2 days and a maximum of 45.7 days for the latissimus dorsi flaps. 24 flaps (23.3%) in total had to be revised with bleeding being the main cause of immediate revisions (41.7% of all revisions). 5 flaps (4.85% of all flaps) were lost despite a revision procedure meaning a successful revision rate in 79.2% of all revisions. CONCLUSION: Microvascular reconstruction procedures are safe and should be considered as standard procedures for reconstruction of large defects especially in high volume training centres. Intensive flap monitoring and early revisions maximize the flap outcome.

Numb chin syndrome: a rare and often overlooked symptom.

Numb chin syndrome (NCS) describes a sensory neuropathy characterized by numbness in the distribution of the terminal branch of the mandibular division of the trigeminal nerve. Benign as well as malignant diseases are known to cause NCS. This is often misdiagnosed, and in some cases the symptom may lead to a late detection of malignancy. Reports of 10 cases in which NCS was the presenting and isolated symptom, caused by extracranial malignancies, drugs, or dental/surgical interventions, are presented. This article outlines the symptoms and the diagnostic approaches taken, provides a short review of the etiology and pathogenesis, and proposes diagnostic criteria and treatment of NCS. Both medical practitioners and dentists need to be aware of the relationship between malignancies and paresthesia of the chin or complete loss of sensation in partial segments of the jaw. In addition, dentists should be aware of the diagnostic limitations of an orthopantomogram to detect underlying diseases beyond localized dental disorders.

Lack of evidence for predictive and prognostic value of cyclin D1 gene polymorphism CCND1 G870A for oral squamous cell carcinoma.

BACKGROUND/AIM: Cyclin D1 gene (CCND1) has a G to A polymorphism at the splice donor site of exon 4, position 870. The A allele codes for a truncated variant, cyclin D1b, which may have higher transforming activity. Data regarding the predictive and prognostic value of the CCND1 G870A polymorphism in tumors are controversial. We aimed to examine this polymorphism in patients with oral carcinoma. MATERIALS AND METHODS: Genotyping of CCND1 G870A was determined by means of direct sequencing in 83 patients with oral carcinomas and in 102 healthy controls. Association with clinical outcomes was evaluated statistically. RESULTS: We failed to find any significant association of CCND1 G870A with risk of oral carcinomas in this German population, with clinical and pathological features of the tumours or with overall survival of the patients. CONCLUSION: Our results suggest that CCND1 G870A has no, or only very limited, predictive and prognostic value for oral carcinoma.

Intraoperative efficiency of fluorescence imaging by Visually Enhanced Lesion Scope (VELscope) in patients with bisphosphonate related osteonecrosis of the jaw (BRONJ).

OBJECTIVES: The purpose of this study was to determine the potential of tissue fluorescence imaging by using Visually Enhanced Lesion Scope (VELscope) for the detection of osteonecrosis of the jaw induced by bisphosphonates (BRONJ). METHODS: We investigated 20 patients (11 females and 9 males; mean age 74 years, standard deviation ± 6.4 years), over a period of 18 month with the diagnosis of BRONJ in this prospective cohort study. All patients received doxycycline as a fluorescending marker for osseous structures. VELscope has been used intraoperatively using the loss of fluorescence to detect presence of osteonecrosis. Osseous biopsies were taken to confirm definite histopathological diagnosis of BRONJ in each case. RESULTS: Diagnosis of BRONJ was confirmed for every patient. In all patients except one, VELscope was sufficient to differentiate between healthy and necrotic bone by visual fluorescence retention (VFR) and visual fluorescence loss (VFL). 19 cases out of a total of 20 showed no signs of recurrence of BRONJ during follow-up (mean 12 months, range 4-18 months). CONCLUSION: VELscope examination is a suitable tool to visualize necrotic areas of the bone in patients with bisphosphonate related osteonecrosis of the jaw. Loss of fluorescence in necrotic bone areas is useful intraoperatively as a tool for fluorescence-guided bone resection with relevant clinical interpretation.

Incidence of bisphosphonate-related osteonecrosis of the jaw in consideration of primary diseases and concomitant therapies.

BACKGROUND: Since its first description by Marx in 2003, the etiology of bisphosphonate-related osteonecrosis of the jaw (BRONJ) is the subject of numerous scientific discussions for oral and maxillofacial surgeons. Many retrospective studies on its etiology and pathogenesis have been carried out to explain pathological mechanisms; most of them just take a close look at the issue of dosage and application. Recently, attempts have been made, to identify co-factors which might promote the development of BRONJ. PATIENTS AND METHODS: The present study is based on data of 169 patients with osseous metastatic malignancies. All patients received intravenous bisphosphonate therapy. On the basis of medical history, malignancy, and primary treatment, the modality of bisphosphonate therapy, and existing comorbidities and medication were analyzed. The role of immunosuppressive drugs, influence of underlying diseases, and general factors such as age and gender were examined. The predictability of necrotic involvement, influenced by the underlying malignancy and its specific therapy, e.g. radiation and cytostatic therapy were analyzed and statistically evaluated. RESULTS: A total of 8.9% (n=15) of patients developed BRONJ. The average time between diagnosis of malignancy and BRONJ was 80 months. Nine patients suffered from breast cancer, five had prostate cancer and one renal cancer. Separation into stage and histological subtype did not show any significant correlation, nor did age or gender, to the occurrence of BRONJ. However statistical analysis did show a significant correlation concerning monocytostatic (p=0.0215) and triple-cytostatic therapy (p=0.0137). The majority of patients with BRONJ (60%) received a bisphosphonate therapy including zoledronate. Single application with one bisphosphonate was administered in 28 cases; 44 patients had a medical history of different use of bisphosphonate. Concomitant medication did not suggest possible correlation, nor did accompanying diseases, arterial hypertension (33.33%) or arterial microcirculatory disturbances (20%). CONCLUSION: The evaluation of our results is pioneering. The influence of cytostatics and combined therapy of cytotoxic drugs on the pathogenesis of BRONJ is demonstrated here statistically. We confirmed a drug- and dose-dependent occurrence of BRONJ. Further prospective studies should be performed to elucidate the role of tissue perfusion and oxygen saturation, and the influence of immunosuppressive drugs in relation to the occurrence of BRONJ, as well as on wound healing of initial lesions.

Cone beam computed tomography in the differential diagnosis of mental neuropathy (numb chin syndrome) in metastatic colon cancer.

Neuropathy of the mental nerve, also referred to as numb chin syndrome (NCS), is a rare finding that demands for accurate differential diagnosis and therapy. This is a report of two patients with a history of colonic cancer, who experienced a progressive hypaesthesia of one side of the corner of the mouth, lower lip and chin, associated with intermittent phases of pain some weeks prior to admission to hospital. Orthopantomograms were insufficient to disclose the relationship between the osseous lesion and the nerve canal. Cone beam computed tomography (CBCT) clearly disclosed the widely spreading, in-growing tumour of the mandible and the affection of the canal's boundary. CBCT is recommended as the imaging modality of primary choice to disclose apparent osseous affections of the mandibular canal and foramina associated with NCS, in particular in the diagnostics of outpatients admitted to specialized clinics and in the dental office.

Amplification of the PPFIA1 gene region on 11q13 in oral squamous cell carcinomas (OSCC).

INTRODUCTION: Analyzing chromosomal amplifications delivers valuable information for identification of oncogenes. For carcinomas of the oral cavity only few genes have been identified in amplified regions. The aim of this study was to search genes in amplified regions as possible biomarkers and targets for novel therapies. MATERIAL AND METHODS: DNA from 10 carcinomas of the floor of the oral cavity was examined using a 500K Array GeneChip (Affymetrix 6.0) to detect chromosomal losses, gains or amplifications. Suspicious alterations were validated on tissue microarrays using fluorescence in situ hybridization (FISH) with respective probes. RESULTS: FISH-validation on tissue arrays confirmed PPFIA1 amplifications as one of the most frequent events (32.6%). High (10-20 signals) and low (<10 signals) amplification of PPFIA1 was found in 10.9% (5/46) and 21.7% (10/46) tumours, respectively. Fine mapping with overlapping FISH probes showed co-amplification of PPFIA1 and the Cyclin D1 gene which are approximately 600 kb apart from each other, likely in the same amplicon. DISCUSSION: PPFIA1 was frequently co-amplified with the Cyclin D1 gene in oral carcinomas and could present a biomarker as well as a novel target for specific gene therapy. Further studies are necessary to investigate the role of PPFIA1 in development and pathogenesis of oral carcinomas.

Craniofacial fibrous dysplasia (CFD) of the maxilla in an 11-year old boy: a case report.

We present the case of a surgically treated 11-year old boy with a diagnosis of craniomaxillofacial fibrous dysplasia (CFD) in the maxillary sinus. When first seen in the outpatient clinic of our department he had minimal symptoms. After initial radiological diagnostics by computed tomography scans (CT-scans) the patient was treated operatively by radical excision of the tumor. The radiographs showed the typical intramedullary located and well-defined lesions, which eroded the cortical bone with the typical appearance of fibrous dysplasia. The histopathology showed the typical curved extending fibrous trabeculae in C, O and Y-shape which were embedded in a moderately cellular morphologically inconspicuous stroma, confirming the initial suspicion of fibrous dysplasia of the maxillary bone. Cone beam tomography was a valuable tool in determining the re-ossification of bone at the affected side. Local resection can be curative in limited disease.