Management of anticoagulated patients in dentoalveolar surgery: a clinical comparative study.

OBJECTIVES: This prospective, comparative, clinical study analyzed the postoperative bleeding risk of patients on anticoagulation therapy (AT) who were undergoing tooth extractions and osteotomies. MATERIALS AND METHODS: Patients with the following ATs were included (test groups): (1.) platelet aggregation inhibitors (PAIs), (2.) vitamin K inhibitors, (3.) low molecular weight heparin (LMWH), and (4.) direct oral anticoagulants (DOACs). Patients in the control group were not on any AT (non-AT group). Patients were subdivided into the following treatment groups: (1.) single tooth extraction, (2.) serial extraction (≥ 2 adjacent teeth), and (3.) tooth osteotomy. Pre-, intra-, and postoperative data concerning the treatment, extent of the surgery, and bleeding were recorded and statistically evaluated. RESULTS: There were 15 postoperative bleeding events in 838 patients (1.7%): four (0.7%) in the non-AT group (n = 603 patients) and 11 (4.7%) in the AT group (n = 235 patients). The surgical procedure had no statistically significant effect on postoperative bleeding frequencies. Patients taking vitamin K inhibitors had a significantly higher risk of postoperative bleeding compared with patients without AT (p < 0.00001). Four patients were hospitalized due to the severity of the bleeding (vitamin K inhibitor group). Postoperative bleeding events were all controlled with local hemostatic measures. CONCLUSIONS: The postoperative bleeding risk after tooth extractions and osteotomies in patients continuing AT is low, and bleeding can be controlled with local hemostatic measures. CLINICAL RELEVANCE: AT should be continued in patients undergoing tooth removal procedures under the provision that local hemostatic measures are applied.

Survival benefit for patients treated in a certified head and neck tumor center.

OBJECTIVE: Increasing effort has been put in the implementation and certification of head and neck tumor centers in order to establish standardized, quality assured health care for head and neck tumor patients. This study evaluated survival rates after treatment in a certified head and neck tumor center (CHNTC) vs. a non-certified head and neck tumor center (non-CHNTC) in Middle Franconia, Germany. PATIENTS AND METHODS: Age, sex, possible obituary, and typical relevant prognostic variables were analyzed. Diagnosis was recorded according to ICD10. Clinical and pathological TNM staging, tumor grading, localization, R-stage, and morphology were assessed (ICD-0). Patients diagnosed with oral cancer (N=1047) were divided into groups based on where they received their primary treatment; CHNTCs or non-CHNTCs. RESULTS: Patients treated at CHNTCs had significantly higher survival rates vs. those treated at non-CHNTC (p=0.023) in univariate analysis. In a Cox regression model, survival rates for patients with pN0 and pN+ stage were similar at both types of centers. Men with pN0 had significantly lower survival rates (HR=0.497, p<0.001). Age had a statistically significant influence on survival rates independently from pN stage (HR=1.031 per year, p<0.001 in both groups). CONCLUSIONS: Patients treated at CHNTC had better survival rates than those treated at non-CHNTC.

Gingival esthetics and oral health-related quality of life in patients with cleft lip and palate.

While the oral health-related quality of life (OHRQoL) is known to be reduced in patients with cleft lip and palate (CLP), its inter-dependency with the soft tissue characteristics of the CLP area remains unclear. This study aimed to evaluate the soft tissue characteristics in the treated cleft area in order to investigate whether gingival esthetics correlate with OHRQoL. Thirty-six patients with unilateral or bilateral CLP (46 cleft areas) were investigated after secondary/tertiary alveolar bone grafting and orthodontic/prosthetic implant treatment using an adapted score to rate gingival esthetics (clinical esthetic score, CES). The patient's OHRQoL was determined using the German short version of the Oral Health Impact Profile questionnaire (OHIP-G14). The results showed a significantly better rating in patients with their own teeth in situ (12.05±1.10) than in patients with implants (6.95±4.78) or prosthetics (4.00±3.58). The best OHRQoL values were achieved by patients with their own teeth integrated into the cleft area (1.32±2.31), followed by patients with implants (2.33±2.33) and prosthetics (3.75±5.87). A significant (P=0.017) correlation was found between OHIP-G14 and CES scores, suggesting an increased OHRQoL in cases with higher oral esthetics in the cleft area. The therapeutic strategy contributes to both gingival esthetics and OHRQoL. The patient's subjective perception of OHRQoL can be attributed to objective gingival esthetic ratings.

Search for a reliable model for bisphosphonate-related osteonecrosis of the jaw: establishment of a model in pigs and description of its histomorphometric characteristics.

The pathogenesis of bisphosphonate-related osteonecrosis of the jaw (BRONJ) remains unknown, and the development of a reliable experimental model would help to improve our understanding of it. We used 12 domestic pigs of which 6 made up the experimental group and were treated with zoledronate 4mg intravenously weekly for 5 weeks, while the control group (n=6) were given no drugs. On day 60 the right second maxillary and mandibular third molars were extracted. Thirty days later 3 animals in each group were killed; the rest were killed 90 days later. Histopathological specimens from the extraction sites were analysed for bone density, collagen architecture, density of osteons, and the amount of non-mineralised bone. Bone density, amount of non-mineralised bone, and density of osteons differed significantly between the 2 groups (p<0.001 in each case), but the chromatic pattern dictated by the collagen architecture did not. Our results correspond to the observations that have been made in patients with BRONJ, which means that the histomorphometric conditions seen in patients can be reproduced in this experimental setting.

[Speech Ability and Psychological Outcome After Treatment of Oral Cancer]. / Sprechqualität und psychische Beeinträchtigung nach der Therapie von Mundhöhlentumoren.

BACKGROUND: In recent years interactions between surgical treatment of oral carcinoma and incidence of anxiety or depression have become a subject of discussions. This prospective study is a comparison between the extent of loss of speech intelligibility and presence of depressive symptoms or anxiety as a result of oral carcinoma. MATERIAL AND METHODS: One year after surgical therapy for oral carcinoma, 90 patients of an average age of 60±12 years were examined. Their speech intelligibility degree was measured using standardized automatic speech recognition (word recognition rate, WR). Symptoms of anxiety and depression were detected by use of HAD-Scales (HADS). Next to the relationship between WR and HADS other influential variables related to WR and HADS were statistically evaluated. RESULTS: The WR average was 53.2±17.2. Female WR was better than male. The difference between tumor classifications T1 and T4 compared to the WR reached statistical significance. Significant differences were detected between WR and "tumor localization", "graft donor site", "graft morphology", "tongue motility", and "tracheostoma" groups. There was a relationship between tongue motility and graft morphology, graft donor site and tumor localization. HAD-Scores in the mean were elevated: HADS-Total=43.3%, HADS-A=43.3% und HADS-D= 51.1%. WR correlates with HADS-D-Subscale, but not with HADS-A-Subscale. CONCLUSION: Communication disorders as a result of neoplasmic orofacial surgery may be related to extent of the treatment and to affective impairments. This should receive attention in the concept of rehabilitation.

Management of anticoagulated patients in implant therapy: a clinical comparative study.

OBJECTIVES: This prospective clinical comparative study aimed to analyze the postoperative bleeding risk of patients continuing their anticoagulation therapy (AT) and undergoing implant surgery and bone grafting procedures. MATERIALS AND METHODS: The treatments ranged from the insertion of single or multiple dental implants over implant exposures to sinus floor augmentation and vertical and/or lateral bone grafting with autologous bone grafts. The patients of the test groups (AT groups) were treated with platelet aggregation inhibitors (PAIs), Vitamin-K inhibitors, Vitamin-K inhibitor withdrawal bridged with heparin (LMWH), or new/direct oral anticoagulants (NOACs/DOACs). Patients of the control group were non-anticoagulated (non-AT group). Surgical procedures were performed in the same manner in all groups. Pre, intra, and postoperative data concerning the treatment, extent of the surgery and bleedings was recorded and statistically evaluated. RESULTS: There were seven postoperative bleedings in 564 patients (1.2%), four in the AT groups (3.4%), and three in the non-AT group (0.6%). No thromboembolic complication occurred in the whole observation period. The invasiveness of the surgical procedure had no statistically significant effect on bleeding frequencies. Patients taking Vitamin-K inhibitors had a significantly higher risk of a postoperative bleeding compared to patients without any AT (P = 0.038). Two patients were hospitalized due to the severity of the bleeding as a precautionary measure (one in the non-AT and one in the PAI group). All bleedings were easily controllable with local hemostatic measures. There was no postoperative bleeding recorded for patients taking DOACs. CONCLUSIONS: Anticoagulation therapy should be continued in patients undergoing implant surgery and bone grafting procedures avoiding thromboembolic complications. Surgeons should always apply the most minimally invasive approach to reduce postoperative risks and be able to apply local hemostatic measures in terms of a bleeding complication.

Macrophage polarisation changes within the time between diagnostic biopsy and tumour resection in oral squamous cell carcinomas--an immunohistochemical study.

BACKGROUND: The prognosis of solid malignancies has been shown to depend on immunological parameters, such as macrophage polarisation (M1/M2). Recently, it was reported that preoperative oral surgery leads to a worsening of oral squamous cell carcinomas (OSCC) prognosis. Diagnostic incision biopsies are oral surgery procedures that might lead to healing-associated M2 macrophage polarisation with a potential negative influence on tumour biology. No studies have compared macrophage polarisation in OSCC biopsies and tumour specimens. METHODS: Preoperative diagnostic incision biopsies (n=25) and tumour resection specimens (n=34) of T1/T2 OSCC were processed for immunohistochemistry to detect CD68-, CD11c-, CD163- and MRC1-positive cells. Samples were digitised using whole-slide imaging, and the expression of macrophage markers was quantitatively analysed. RESULTS: Carcinoma tissues obtained during OSCC tumour resections showed a significantly (P<0.05) increased CD163 cell count (M2 macrophages) compared with tissues obtained during preoperative incision biopsies. Additionally, the CD163/CD68 ratio (an indicator of M2 polarisation) was significantly (P<0.05) higher in tumour resection specimens than in biopsies. CONCLUSIONS: This study revealed for the first time an increase in M2 polarisation in samples obtained during OSCC tumour resection surgery compared with preoperative incision biopsies. The biopsy-induced tissue trauma might explain the observed shift in macrophage polarisation towards the tumour-promoting M2 type and could lead to accelerated tumour progression.

Perioperative factors that influence the outcome of microsurgical reconstructions in craniomaxillofacial surgery.

Microsurgical tissue transfer is a well-established way of reconstructing the head and neck, but there are still many postoperative complications that require revision. The aim of this study was to clarify perioperative factors and characteristics of patients that influence the success of the flap and the need for revision. We retrospectively studied 368 patients who were treated with microsurgical free tissue transfer in the head and neck area at the Department of Oral and Maxillofacial Surgery at the University Medical Centre, Erlangen, between 2004 and 2009. Investigations concentrated on patients' characteristics and operative factors. Free scapular or parascapular flaps (n=161, 44%) and radial forearm flaps (n=119, 32%) were predominantly used for the reconstruction of major defects in the mandible and the floor of the mouth. In 39 patients (11%) revision was required, which resulted in a success rate of 96%. There was a significant association between preoperative American Society of Anesthesiologists (ASA) grade and postoperative survival of the flap (p=0.04). Patients previously treated by irradiation required significantly more revisions than those not so treated (p=0.04). The use of vein grafts was also significantly associated with the need for revision (p=0.02). The ASA grade influenced the success rate but was not associated with the number of revisions. These factors must be taken into consideration when intervention is planned to reduce the number of postoperative complications and interventions further.

Factors influencing relative speech intelligibility in patients with oral squamous cell carcinoma: a prospective study using automatic, computer-based speech analysis.

Oral squamous cell carcinoma (OSCC) and its treatment impair speech intelligibility by alteration of the vocal tract. The aim of this study was to identify the factors of oral cancer treatment that influence speech intelligibility by means of an automatic, standardized speech-recognition system. The study group comprised 71 patients (mean age 59.89, range 35-82 years) with OSCC ranging from stage T1 to T4 (TNM staging). Tumours were located on the tongue (n=23), lower alveolar crest (n=27), and floor of the mouth (n=21). Reconstruction was conducted through local tissue plasty or microvascular transplants. Adjuvant radiotherapy was performed in 49 patients. Speech intelligibility was evaluated before, and at 3, 6, and 12 months after tumour resection, and compared to that of a healthy control group (n=40). Postoperatively, significant influences on speech intelligibility were tumour localization (P=0.010) and resection volume (P=0.019). Additionally, adjuvant radiotherapy (P=0.049) influenced intelligibility at 3 months after surgery. At 6 months after surgery, influences were resection volume (P=0.028) and adjuvant radiotherapy (P=0.034). The influence of tumour localization (P=0.001) and adjuvant radiotherapy (P=0.022) persisted after 12 months. Tumour localization, resection volume, and radiotherapy are crucial factors for speech intelligibility. Radiotherapy significantly impaired word recognition rate (WR) values with a progression of the impairment for up to 12 months after surgery.

i.lect, a pre-graduate education model of implantology.

OBJECTIVE: In 2008, a consensus meeting of the Association for Dental Education in Europe stated that dental implant treatment represents a popular treatment alternative and, therefore, it should be an integral part of dental student pre-graduate education. In 2009, the Friedrich-Alexander University, Erlangen-Nuremberg implemented a voluntary, structured, education program for pre-graduate dental students, called 'i.lect'. The present study evaluated the effectiveness of the i.lect program. METHODS: Concurrent to the dental curriculum, the i.lect program provides 200 hours in 3 years of theoretical and practical education on all aspects of modern dental implantology. We recruited dental students in the i.lect program and additionally students from 15 other universities that voluntarily participated in a single, 3-day implantology camp (R = 58). To demonstrate their knowledge on dental implant issues, both student groups completed a written examination that covered 'Basic information and materials of implantology', 'Implant planning' and 'Soft tissue management'. RESULTS: The students in the i.lect program achieved higher scores than students from the implantology camp on questions concerning 'basic implantology' and 'implant planning'. CONCLUSION: The results indicated that the structured i.lect undergraduate curriculum enhanced individual knowledge in the specific field of implantology. This program could have pilot character for use in other universities.

Oral findings associated with primary hyperoxaluria type I.

In the present paper we report the oral findings of a patient who was diagnosed with hyperoxaluria. Hyperoxalurias can basically be classified as primary and secondary, with the first being inborn errors of metabolism and the second a result of excessive oxalate intake. Primary hyperoxalurias form a rare group of metabolic diseases that are inherited in the autosomal recessive fashion. The affected genes code for specific hepatic enzymes that are involved in glyoxylate metabolism and their deficiency results in overproduction of oxalate. Two different types are described: Primary hyperoxaluria type I results from a deficiency of peroxisomal enzyme alanine-glyoxylate aminotransferase and the more rare type II from a deficiency of cytosolic enzyme D-glycerate dehydrogenase. Since oxalate is primarily excreted through the kidneys, abnormally high concentration of oxalate in the urine occurs. This can in turn result in recurrent kidney stones and parenchymal renal damage and end-stage renal disease (ESRD). Inability to further excrete oxalate through the kidneys leads to its deposition in various organs (oxalosis). Several oral findings have been described in patients with oxalosis, most important of whose are bone resorption in the jaws, external root resorption and rapidly progressive dental mobility, as well as dental pain associated with deposition of oxalate in the dentine and the pulp.

Prediction of recurrence using exfoliative cytology and melanoma-associated antigen-A mRNA analysis following wide excision of oral squamous cell carcinoma: short report.

BACKGROUND: Oral squamous cell carcinoma (OSCC) is the sixth most common cancer. The local recurrence of OSSC might result from the existence of occult cancer cells around tumour margins. Exfoliative cytology has lately gained great importance as a method for obtaining RNA samples from suspicious oral mucosal lesions in order to carry out molecular diagnosis. In addition, melanoma associated-A antigens (MAGE-A) are expressed in various tumours and their detection is a highly accurate sign that cancer cells are present. OBJECTIVE: The prediction of a recurrence using MAGE-A mRNA expression analysis to follow-up OSCC cases using a newly established molecular diagnostic technique applied to cytological materials. METHODS: RNA was extracted from three recurrent OSCC cases and from 20 healthy volunteers as a control group using a cytobrush. The expression of MAGE-A3, A4, A6, A10 and A12 was investigated in these specimens using quantitative real-time (RT-PCR). RESULTS: There was no expression of MAGE-A in the specimens of normal oral mucosa. However, the expression analysis of five different MAGE-A genes indicated a high potential for malignant change in biopsy-proven recurrent OSCC cases. Except for MAGE-A10, the rest of the genes were expressed in different ratios by the three recurrent cases, which had been determined on histopathology to be OSCC or carcinoma in situ. CONCLUSION: It is suggested that analysis of MAGE-A expression may be used as a risk prediction method in the diagnosis of recurrence after wide excision of OSCC to enhance the accuracy of exfoliative cytology, which has limitations due to false negative and false positive results.

Air gun pellet remaining in the maxillary sinus for 50 years: a relevant risk factor for the patient?

The authors report the case of a 62-year-old man referred to the department of oral and maxillofacial surgery because of a clinical suspicion of palate carcinoma. Incidentally, diagnostic radiology showed a metallic foreign body in the left maxillary sinus. Anamnestic data revealed that a shot from an air gun accidentally hit the patient's left cheek in 1957. The lead-containing air gun pellet was removed by endoscopic antrostomy and the diagnosis of squamous cell carcinoma was confirmed by histopathological examination. 50 years after the pellet's impact, toxicological blood analysis showed no increased blood lead level. It remains unclear whether the air gun pellet has a potential toxicological effect or is related to the development of the patient's oral carcinoma. In this context the article reviews the literature and discusses the necessity of removing metal-containing foreign bodies, the role of lead in chronic toxicity and its possible carcinogenic effect in humans.

Effects of osteoinduction on bone regeneration in distraction: results of a pilot study.

Rate and frequency of distraction as well as stimulatory effects transmitted by growth factors and local gene therapy have a decisive influence on bone regeneration. In a pilot study we tested the effect of four different morphogenetic and mitotic proteins and a genetically transferred vector system on bone healing in continuous osteodistraction in a large animal experiment on 24 Goettingen mini-pigs. For this purpose bone morphogenetic protein (BMP-2), BMP-7, TGF-beta, IGF-1 and a liposome vector were instilled into the distraction gap. The animals were killed after 1-4 weeks of consolidation. Histological and radiological evaluations showed maximum bone formation after the application of BMP-2/7, whereas the application of TGF-beta, IGF-1 and the liposomal vector had only a limited effect on bone regeneration. The quantitative analysis demonstrated an average amount of bone in the distraction gap of 50% and 61% after instillation of BMP-2 and 7, respectively. The BMP-2 expression, however, was maximal after induction with the non-viral vector. Only after BMP-2/7 application could physical, radiographic and histological evidence of bone union be detected. In bone distraction with a short observation period the application of morphogenetic proteins seems to enhance bone regeneration significantly. Before application in humans further studies are necessary to measure the dose-effect relationship, the mode of application and the efficacy of different inductive proteins. The combination of osteodistraction with osteoinduction, however, could shorten treatment times dramatically.

A metalloproteinase-9 polymorphism which affects its expression is associated with increased risk for oral squamous cell carcinoma.

AIM: In light to recently found contribution of factors associated with angiogenesis, thrombosis and inflammation to carcinogenesis, we investigated the possible association of metalloproteinase-9 (MMP-9) with increased risk of oral cancer. METHODS: In DNA samples of 152 patients with oral squamous cell carcinoma and 162 healthy controls of comparable ethnicity, age and sex, we studied the -1562 C/T polymorphism in the MMP-9 gene promoter, which affects its transcription. RESULTS: The detected frequency for the high expression T allele in the patients' group was significantly increased in comparison to that of the control group (22% versus 15%, respectively; P<0.05). This difference was due to the relative increase of C/T heterozygotes in the group of patients, in comparison to controls (P<0.05, 95% OR 1.92, CI 1.21-3.06). The same pattern of significance was observed between controls and the subgroups of patients with initial (I & II) stages of cancer, without positive family history of cancer or thrombophilia, with smoking and alcohol abuse habits. CONCLUSIONS: The investigated MMP-9 polymorphism has a strong association with increased risk for developing oral cancer in a subset of the general population. These results are in accordance to previous studies of constitutive expression and secretion of MMP-9 in invasive oral carcinoma cell lines. The observation that T allele carriers have an increased risk for developing oral cancer only in initial stages, but not in advanced ones, may be due to the role of MMP-9 in the inhibition of angiogenesis by generating angiostatin from plasminogen.

[Enophthalmos correction in complex orbital floor reconstruction : computer-assisted, intraoperative, non-contact, optical 3D support]. / Enophthalmuskorrektur bei komplexer Orbitarekonstruktion : Computerassistierte, intraoperative, berührungsfreie, optische 3D-Unterstützung.

In the case of displacement of the globe such as enophthalmos induced by trauma, the patient is affected on both counts: function and aesthetics. To prevent double vision or conspicuous asymmetry, exact correction of the globe position is required. The aim of this case report is to demonstrate an intraoperative computer-assisted, non-contact, optical 3D procedure for identification of the globe position to aid in placing the eyeball in the position required in complex reconstruction of the orbital floor. A 33-year-old man presented with a sunken eye on the right side in the horizontal and vertical plane 6 months after having undergone surgery elsewhere for a zygomatico-orbital fracture, also including the orbital floor. The patient was affected by double vision and a noticeable defective globe position. In planning the correction of the globe position, a three-dimensional image of the face with opened eyes was made with the optical sensor. Automatic comparison of symmetry revealed enophthalmos of 4 mm on relative en- and exophthalmometry. The decision was made to lift the orbital floor with a split calvarial bone graft. During surgery the position of the globe was also controlled by the three-dimensional optical technique. At the end of surgery there was exophthalmos of 1 mm. Six weeks after surgery the patient was not affected by any double vision. After 3 and 24 months enophthalmos was 1 mm. This case demonstrates how the non-ionizing, non-contact, optical 3D technique can help in planning, intraoperative transformation, and clinical monitoring to identify the correct position of the corneal vertex in complex orbital floor reconstruction.

[Computer-assisted orbital floor reconstruction. Use of a CAD/CAM implant with intraoperative contact-free 3D endo- and exophthalmometry]. / Computerassistierte Enophthalmuskorrektur. Nutzung eines CAD/CAM-Implantats unter intraoperativer, berührungsfreier 3D-en- und exophthalmometrischer Kontrolle.

Pronounced enophthalmos can restrict patients both functionally and aesthetically. Typical symptoms are double vision on both eyes and obvious asymmetry, both of which were present in the 67-year-old male patient presented in this paper. The resulting data of computed tomography was used to fabricate a patient specific ceramic implant for reconstruction of the left orbital floor with an enophthalmos of 4mm. During the surgery the implant fitted anatomically correct, but exophthalmos occurred. The implant needed to be regraded and recontoured in the dorsal fraction, so that overcorrection could be reduced. With the assistance of optical 3D en- and exophthalmometry during surgery, the position of the cornea vertex was reproducible measured. At the end of surgery, exophthalmos was 1.5 mm. After 12 months, enophthalmos of only 1mm exists. This case displays the combination of a patient specific fabricated implant for reconstruction of the orbital floor with optical 3D-en-and exophthalmometry to correct enophthalmos with a high degree of accuracy. Therefore these two techniques in combination should be used when complex corrections of enophthalmos are needed.

State of the art of fusion of computed tomography data and optical 3D images.

When three-dimensional imaging is necessary in dentistry, oral surgery or maxillofacial surgery, conventional computed tomography or cone beam computed tomography is chosen regularly. However, there are two obvious drawbacks. Metallic restorations lead to pronounced streak artefacts in conventional computed tomography. Moreover, the resolution of both conventional computed tomography and cone beam computed tomography is limited to 0.3 mm. This resolution is not sufficient for the fabrication of dental restorations. In order to improve the quality of the two different computed tomography techniques and to eliminate streak artefacts, fusion with optical 3D images can be considered. The resolution of optical 3D images can reach the range of some microms depending on the calibration of the sensor. Metal artefacts do not occur. The fusion of computed tomography images without artefacts and optical 3D images leads to a mean deviation of corresponding points for the two imaging techniques of 0.1262 +/- 0.0301 mm. When computed tomography images with metal artefacts are used, the deviation increases up to 0.2671 +/- 0.0580 mm. The accuracy of image fusion is significantly reduced by metal artefacts (p < 0.0005). When image fusion of computed tomography and optical 3D images is used in clinical studies, the mean deviation of corresponding points for the two imaging techniques for mandible and maxilla is 0.66 +/- 0.49 mm and 0.56 +/- 0.48 mm, respectively. The available data on image fusion show that the quality of computed tomography data without streak artefacts can be significantly improved by registration with optical 3D images. The precision of the fused images exceeds the resolution of the original computed tomography. When streak artefacts are present, image fusion makes it possible to increase the quality of the data to the level of the original resolution of computed tomography without artefacts.

[Surgical management of obstructive sleep apnea]. / Chirurgische Behandlungsmöglichkeiten der obstruktiven Schlafapnoe.

INTRODUCTION: Obstructive sleep apnea (OSA) is a common disorder in adults, however it also occurs in neonates with severe mandibular hypoplasia. The clinical significance of OSA results from hypoxemia and sleep fragmentation due to a collapse of the upper airway. Recently OSA has received much attention due to its potentially serious consequences on cardiac function. Besides daytime sleepiness and fatigue life expectancy is significantly shortened by a higher risk for apoplectic insults and heart failures. This paper reviews common surgical procedures with an emphasis on jaw advancement procedures. MATERIAL AND METHODS: In six adults (mean age 46,9 ys; 2 female, 4 male; BMI averaged 28kg/m(2)) suffering from OSA with a history of a long-lasting unsuccessful continuous positive airway pressure (CPAP) therapy a bimaxillary advancement was performed. The respiratory disturbance was preoperatively evaluated by polysomnography; daytime sleepiness was recorded according to the 'Epworth Sleepiness Scale'. Controls were performed six months after therapy. All patients had a regular intermaxillary relation. Bimaxillary advancement was planned and performed according to the principles of cranio-maxillofacial corrective surgery. To widen the posterior airway space much attention was focused on the advancement of the mandible by 10mm. RESULTS: The apnea/hypopnea index decreased from preoperatively 37/h to 4/h after treatment. The minimal peripheral oxygen saturation increased from 78% to 89%, whereas the average oxygen saturation raised from 92 to 95%. The arousal index decreased from 24/h to 9/h. Periods of snoring were reduced from 29,5% to 6,9%. According to the 'Epworth Sleepiness Scale' the patients' estimation improved from a level of 11 to 4. Sleep had a recuperating effect. All surgical procedures were uneventful. CONCLUSION: Standard treatment of OSA is the CPAP-therapy. In some patients, however, CPAP-therapy cannot be applied, fails or is not well accepted. A great variety of surgical procedures for the treatment of OSA have been described. Bimaxillary advancement in adults and osteodistraction in neonates are safe and successful surgical techniques for an immediate improvement in OSA. Osteodistraction treatment can help to avoid tracheotomy in neonates.

The effect on bone regeneration of a liposomal vector to deliver BMP-2 gene to bone grafts in peri-implant bone defects.

Successful bone-implant osseointegration in large peri-implant bone defects is often difficult, even through autologous bone grafting. Recently, cell-mediated regional gene therapy was introduced to deliver potent morphogens or growth factors in regenerative medicine. We applied liposomal vectors carrying bone morphogenetic protein (BMP)-2 cDNA directly into freshly created peri-implant bone defects on pig calvariae, with or without autologous bone graft. The BMP-2 gene was efficiently introduced into immigrating cells and trabecular cells lining the marginal bone surrounding the bony defect. After 1 week, abundant BMP-2 protein was detected throughout the peri-implant bone defect by immunohistochemistry. At 4 weeks, BMP-producing cells were still present in the defect and peri-implant area, which significantly enhanced new bone formation, compared with the control groups. Interestingly within a week of BMP-2 gene delivery with bone grafts, most osteoblastic cells lining the grafted bone chips also produced BMP-2. Particulated bone was immediately reorganized into newly formed trabecular bone. Grafted bone without BMP-2 gene delivery was still scattered and new bone matrix formation was not detected until 4 weeks after bone grafting. In conclusion, direct application of the BMP-2 gene using a liposomal vector enhanced bone regeneration in a bony defect and gene delivery combined with bone graft could induce a rapid osseointegration of the bone-implant interface at earlier stage.