Prospective Clinical Multicenter Study Evaluating the 5-Year Performance of Zirconia Implants in Single-Tooth Gaps.

PURPOSE: In recent years, ceramic implants made of zirconia have secured a niche position next to established titanium implants, due partly to new scientific findings and positive clinical experience with the handling of ceramic implants. The aim of this study was to assess the clinical and radiographic data for monotype ceramic implants that have remained in place for 60 months under masticatory loading. MATERIALS AND METHODS: In 2011, this prospective clinical study included patients with a single-tooth gap in the maxilla and mandible. Monotype ceramic implants (Straumann) were used according to a standard protocol. Provisional prostheses were placed after 3 months, followed by final prostheses 3 months later. Patients were invited for a 60-month follow-up. Implant survival was analyzed from lifetime data. Success rates and crestal bone levels were evaluated from implant placement to 6, 12, 36, and 60 months after surgery. RESULTS: From the initial 44 patients recruited, 36 were analyzable for the 60-month follow-up. With one implant lost before the 6-month followup, the survival rate after 60 months was 97.7%, and the mean survival time was 58.7 months. Sixty months after implant placement, the success rate was 97.2% (95% confidence interval = 84.6% to > 99.9%). Mean bone loss after 60 months was 0.99 (± 0.59) mm. CONCLUSION: After 60 months, monotype ceramic implants made of zirconia achieved success and survival rates comparable with those reported for titanium implants in selected patient populations. Ceramic implants can be used as an alternative to titanium implants at the request of patients and if specifically indicated, for example, due to titanium intolerance.

A prospective clinical study to evaluate the performance of zirconium dioxide dental implants in single-tooth edentulous area: 3-year follow-up.

BACKGROUND: Traditionally, dental implants have been made from titanium or titanium alloys. Alternatively, zirconia-based ceramic implants have been developed with similar characteristics of functional strength and osseointegration. Ceramic implants offer advantages in certain settings, e.g. in patients who object to metal dental implants. The aim of this study was to investigate the mid-term (36 months) clinical performance of a ceramic monotype implant in single-tooth edentulous area. METHODS: This was a prospective, open-label, single-arm study in patients requiring implant rehabilitation in single-tooth edentulous area. Ceramic implants (PURE Ceramic Implant, Institut Straumann AG, Basel, Switzerland) with a diameter of 4.1 mm were placed following standard procedure and loaded with provisional and final prostheses after 3 and 6 months, respectively. Implant survival rate and implant success rate were evaluated and crestal bone levels were measured by analysing standardized radiographs during implant surgery and at 6, 12, 24 and 36 months. RESULTS: Forty-four patients received a study implant, of whom one patient withdrew consent after 3 months. With one implant lost during the first 6 months after surgery, the implant survival rate was 97.7% at 6 months. No further implants were lost over the following 30 months, and 3 patients were lost to follow-up during this time frame. This led to a survival rate of 97.5% at 36 months. Six months after implant surgery 93.0% of the implants were considered "successful", increasing to 97.6% at 12 months and remaining at this level at 24 months (95.1%) and 36 months (97.5%). Bone loss was most pronounced in the first half-year after implant surgery (0.88 ± 0.86 mm). By contrast, between 12 and 36 months the mean bone level remained stable (minimal gain of 0.06 [± 0.60] mm). Hence, the overall bone loss from implant surgery to 36 months was 0.97 (± 0.88) mm. CONCLUSIONS: In the follow-up period ceramic implants can achieve favourable clinical outcomes on a par with titanium implants. For instance, these implants can be recommended for patients who object to metal dental implants. However, longer term studies with different edentulous morphology need to confirm the present data. TRIAL REGISTRATION: Registered on www.clinicaltrials.gov : NCT02163395 .

Perioperative Bromelain Therapy after Wisdom Teeth Extraction - A Randomized, Placebo-Controlled, Double-Blinded, Three-Armed, Cross-Over Dose-Finding Study.

Reduction in postoperative edema and inflammatory reactions is the key to the posttraumatic regeneration process. Use of bromelain is well established in this indication, but there is some controversy with regard to the optimal dosing of this drug. The aim of our study was therefore to investigate the efficacy of dosage-dependent therapy with bromelain in patients after wisdom teeth extraction by comparing the registered dosage 1000 FIP (Fédération Internationale Pharmaceutique) against higher dosages of 3000 FIP and 4500 FIP. A total of 75 patients were randomized to one of the three dosage arms, and 68 of these patients were finally analyzed in the modified intention-to-treat population. Patients involved underwent two surgery sessions: one study period being conducted under treatment with bromelain and the other with placebo. Postoperative swelling determined by a 3D face scanning system was defined as the primary endpoint; further efficacy parameters were maximum swelling, pain, difficulty in swallowing, and use of analgesics. A superiority of treatment with 3000 FIP and 4500 FIP versus 1000 FIP could not be demonstrated. The analysis of pooled bromelain treatments versus placebo did, however, show a clear trend in favor of bromelain for all assessments. Adverse events did not occur more frequently under bromelain therapy compared with placebo. This study thus clearly supports the clinical relevance of treatment of postoperative conditions with bromelain, and the recommended daily dose was sufficiently effective in this trial and indication. Copyright © 2016 John Wiley & Sons, Ltd.

Histological evaluation of different abutments in the posterior maxilla and mandible: an experimental study in humans.

OBJECTIVES: To histologically evaluate and compare the performance of healing abutments with either hydrophobic or hydrophilic surface properties in humans. MATERIALS AND METHODS: According to a parallel-group design, titanium implants placed in the posterior mandible and maxilla of 30 patients were randomly assigned to either (1) hydrophobic machined (M), (2) chemically modified hydrophilic (mod) acid etched (MA) titanium (Ti) (modMA1) or (3) modMA Ti- Zirconium alloy (modMA2) healing abutments and left to heal in a transmucosal position. At 8 weeks, the abutments and a limited soft tissue biopsy were harvested according to a standardized procedure and processed for histological analysis (primary outcomes: percentage epithelial- (EC) and subepithelial connective tissue contact (CTC) to the abutment surface). RESULTS: The surgical procedure was associated with an incomplete mucosal coverage of the study abutments in nine patients, and an unintentional submerged healing procedure in three patients. Per protocol analysis (18 patients) has pointed to an improved quantitative EC [modMA2 (53.45 ± 28.25) > modMA1 (32.25 ± 24.3) > M (23.15 ± 16.09)] and CTC [modMA2 (75.12 ± 43.22) > modMA1 (69.41 ± 46.74) > M (47.63 ± 19.28)] (%) to modMA surfaced abutments. CONCLUSIONS: It was concluded that modMA surfaces may have the potential to enhance soft tissue adhesion at the transmucosal aspect of titanium dental implants.

Containment and contouring (CoCoon) technique: a biologically adequate approach to less invasive autogenous preimplant augmentation of bone.

We have analysed retrospectively whether the less invasive zygomatic buttress graft is able to meet the dimensional and biological requirements of preimplant augmentation of bone. A total of 273 patients were treated by zygomatic buttress graft, of whom 42 (12 men and 30 women) met the criteria for inclusion. Intensity of pain was judged by a visual analogue score (VAS). Complications of grafting were evaluated, and dental implants were studied on clinical and radiographic examinations. The Schneiderian membrane was perforated in 13 cases (28%). The mean (SD) postoperative VAS was 3.1 (0.9) at the donor site. The mean (SD) follow-up after implant was 17(8) months. Two grafts were lost, one from initial dehiscence and later infection, and the other from infection. The mean (SD) marginal resorption of bone graft was 0.5 (0.7) mm. No implant was lost during the observation period. The zygomatic buttress graft meets the biological and dimensional requirements of augmentation of bone before implant that allows the dental implants to survive with satisfactory prosthetic rehabilitation.

Comparably accelerated vascularization by preincorporation of aortic fragments and mesenchymal stem cells in implanted tissue engineering constructs.

The demanding need for tissue replacement resulted in manifold approaches for the construction of different tissues. One common problem which hampers the clinical usage of tissue engineering constructs is a limited vascularization. In an attempt to accelerate the vascularization of tissue engineering constructs we compared the usage of bone marrow mesenchymal stem cells (bmMSCs) and fragments derived from the aorta in vivo. Tissue engineering constructs composed of PLGA scaffolds containing Matrigel (n = 8), aortic fragments embedded in Matrigel (n = 8), bmMSCs embedded in Matrigel (n = 8), and aortic fragments embedded in Matrigel combined with bmMSCs (n = 8) were implanted into dorsal skinfold chambers of balb/c mice and analyzed repetitively over 14 days. In all groups a weak inflammatory response was transiently apparent. Vascularization was significantly (p = 0.05) accelerated in bmMSC and aortic fragments containing constructs compared with Matrigel alone, demonstrated by a distinctly increased microvascular density throughout the whole experiment. The combination of bmMSCs and aortic fragments showed no additional effect compared with bmMSCs and aortic fragments alone. The accelerated vascularization and microvascular density of tissue engineering constructs triggered by bmMSCs and aortic fragments is comparable. Thus aortic fragments provide a new promising source for clinical relevant tissue engineering constructs.

Forty sandwich osteotomies in atrophic mandibles: a retrospective study.

PURPOSE: The aim of the present retrospective study was to assess the suitability of segmental mandibular sandwich osteotomy combined with an interpositional autograft to meet the dimensional requirements of preimplant bone augmentation in cases of a severely atrophic mandible. PATIENTS AND METHODS: A total of 27 consecutive patients (6 men and 21 women) were included in the present study. The amount of bone gain was calculated using digital volume tomography before surgery and 3 months after bone augmentation. RESULTS: The postoperative course was uneventful for 18 patients. Temporary sensory disturbances were observed in 6 patients, with complete recovery after 3 to 12 weeks. Dehiscence of soft tissue closure occurred in 3 patients. The mean vertical gain was 3.41 mm (range 0.3 to 12). The mean horizontal gain was 3.08 mm (range 0.2 to 8.5). A total of 88 implants were placed in 40 surgical sites at 12 weeks after bone reconstruction. CONCLUSION: Segmental mandibular sandwich osteotomy is a suitable augmentation procedure in the mandible for the atrophic alveolar ridge and provides adequate height and transversal bone augmentation.

In vitro biomechanical comparison of the effect of pattern, inclination, and size of positional screws on load resistance for bilateral sagittal split osteotomy.

PURPOSE: The purpose of this in vitro investigation was to determine whether the pattern, angle of placement, or size of positional screws affected their ability to resist vertical loads resembling mastication in the bilateral sagittal split osteotomy system. MATERIALS AND METHODS: Standardized bone substitutes were secured with three 12- to 16 mm-long, 1.85-, 2.0-, 2.1-, and 2.4-mm outer diameter, self-tapping titanium screws (Synthes, Solothurn, Switzerland) in various patterns using a positional screw technique. These patterns included transbuccal triangular, intraoral triangular, and transbuccal linear patterns. The models were secured in a jig and subjected to vertical loads by a mechanical testing unit (1475 UPM; Zwick, Ulm, Germany) until failure. Loading test data analysis was based on peak load values resulting in mechanical deformation of the system (1-, 3-, and 5-mm displacement), maximal force, and stiffness (load/displacement slope curve) for each group. Means and standard deviations were derived and compared for statistical significance using univariate analysis of variance with a confidence level of 95% (P values < .05). RESULTS: The designed study demonstrated that 1.85- and 2.0-mm-diameter positional screws provided similar stability in all 3 setups. Three screws placed in an inverted L pattern at 90° (simulating a transbuccal approach) showed significantly higher resistance to vertical forces for advancement movements at 1-, 3-, and 5-mm displacement when compared with the inverted L group of screws placed at an angle (intraoral approach) or 3 screws in a linear pattern placed at 90° (transbuccal approach) (P < .01). CONCLUSIONS: Under the conditions tested in this in vitro study, differences in the load resistance of positional screws placed in a transbuccal or intraoral approach could be demonstrated depending on the fixation technique. The transbuccal group of 3 screws in an inverted L pattern showed significantly greater stability than the intraoral group of 3 screws placed in an inverted L pattern and the transbuccal group of 3 screws in a linear pattern. Resistance to vertical loads with 1.85-mm screws was similar to that with the standard 2.0-mm screws in all 3 setups. The results of this study suggest that the angle of screw placement (surgical approach) and pattern have a greater influence on the stability of the bilateral sagittal split osteotomy system than the screw size.

Introduction of e-learning in dental radiology reveals significantly improved results in final examination.

PURPOSE: Because a traditionally instructed dental radiology lecture course is very time-consuming and labour-intensive, online courseware, including an interactive-learning module, was implemented to support the lectures. The purpose of this study was to evaluate the perceptions of students who have worked with web-based courseware as well as the effect on their results in final examinations. MATERIALS AND METHODS: Users (n(3+4)=138) had access to the e-program from any networked computer at any time. Two groups (n(3)=71, n(4)=67) had to pass a final exam after using the e-course. Results were compared with two groups (n(1)=42, n(2)=48) who had studied the same content by attending traditional lectures. In addition a survey of the students was statistically evaluated. RESULTS: Most of the respondents reported a positive attitude towards e-learning and would have appreciated more access to computer-assisted instruction. Two years after initiating the e-course the failure rate in the final examination dropped significantly, from 40% to less than 2%. CONCLUSIONS: The very positive response to the e-program and improved test scores demonstrated the effectiveness of our e-course as a learning aid. Interactive modules in step with clinical practice provided learning that is not achieved by traditional teaching methods alone. To what extent staff savings are possible is part of a further study.

Effects of VEGF loading on scaffold-confined vascularization.

Adequate vascularization of tissue-engineered constructs remains a major challenge in bone grafting. In view of this, we loaded ß-tricalcium-phosphate (ß-TCP) and porous poly(L-lactide-co-glycolide) (PLGA) scaffolds via collagen coating with vascular endothelial growth factor (VEGF) and studied whether the VEGF loading improves scaffold angiogenesis and vascularization. Dorsal skinfold chambers were implanted into 48 balb/c mice, which were assigned to 6 groups (n = 8 each). Uncoated (controls), collagen-coated, and additionally VEGF-loaded PLGA and ß-TCP scaffolds were inserted into the chambers. Angiogenesis, neovascularization, and leukocyte-endothelial cell interaction were analyzed repeatedly during a 14-day observation period using intravital fluorescence microscopy. Furthermore, VEGF release from PLGA und ß-TCP scaffolds was studied by ELISA. Micromorphology was studied from histological specimens. Unloaded ß-TCP scaffolds showed an accelerated and increased angiogenic response when compared with unloaded PLGA scaffolds. In vitro, PLGA released significantly higher amounts of VEGF compared with ß-TCP at the first two days resulting in a rapid drop of the released amount at the following days up to day 7 where the VEGF release was negligible. Nonetheless, in vivo VEGF loading increased neovascularization, especially in ß-TCP scaffolds. This increased vascularization was associated with a temporary leukocytic response with pronounced leukocyte-endothelial cell interaction at days 3 and 6. Histology revealed adequate host tissue response and engraftment of both ß-TCP and PLGA scaffolds. Our study demonstrates that ß-TCP scaffolds offer more suitable conditions for vascularization than PLGA scaffolds, in particular if they are loaded with VEGF.

IL-1 polymorphism and periimplantitis. A literature review.

The most important factor leading to periimplantitis with bone loss appears to be an inflammatory process due to plaque accumulation. The object of this article was to present a review of the literature on a possible correlation between IL-1 polymorphism and periimplantitis. Research was carried out in the PUBMED and WEB OF KNOWLEDGE literature databases and 27 relevant articles were found. Of these articles, 4 groups of authors came to the conclusion that no correlation exists between IL-1 polymorphism and periimplantitis. In 5 articles by 4 groups of authors, the influence of IL-1 polymorphism on periimplantitis is unclear. 9 studies prove a correlation between IL-1 polymorphism and periimplantitis, and 6 studies also document a direct linkage between gene polymorphism and periimplantitis, if certain cofactors are present. IL-1 polymorphism is frequently connected with "noninfectious periimplant bone loss". Other studies prove that the inflammatory mediators and IL-1beta were significantly elevated in the gingival crevicular fluid (GCF) of infected implants. Many studies document that IL-1 polymorphism alone cannot be considered a risk factor for bone loss, but in combination with smoking, it is closely associated with periimplant bone loss. More studies are needed to discover possible correlations between IL-1 polymorphism and periimplantitis.

Bone repair by cell-seeded 3D-bioplotted composite scaffolds made of collagen treated tricalciumphosphate or tricalciumphosphate-chitosan-collagen hydrogel or PLGA in ovine critical-sized calvarial defects.

The aim of this study was to investigate the osteogenic effect of three different cell-seeded 3D-bioplotted scaffolds in a ovine calvarial critical-size defect model. The choice of scaffold-materials was based on their applicability for 3D-bioplotting and respective possibility to produce tailor-made scaffolds for the use in cranio-facial surgery for the replacement of complex shaped boneparts. Scaffold raw-materials are known to be osteoinductive when being cell-seeded [poly(L-lactide-co-glycolide) (PLGA)] or having components with osteoinductive properties as tricalciumphosphate (TCP) or collagen (Col) or chitosan. The scaffold-materials PLGA, TCP/Col, and HYDR (TCP/Col/chitosan) were cell-seeded with osteoblast-like cells whether gained from bone (OLB) or from periost (OLP). In a prospective and randomized design nine sheep underwent osteotomy to create four critical-sized calvarial defects. Three animals each were assigned to the HYDR-, the TCP/Col-, or the PLGA-group. In each animal, one defect was treated with a cell-free, an OLB- or OLP-seeded group-specific scaffold, respectively. The fourth defect remained untreated as control (UD). Fourteen weeks later, animals were euthanized for histo-morphometrical analysis of the defect healing. OLB- and OLP-seeded HYDR and OLB-seeded TCP/Col scaffolds significantly increased the amount of newly formed bone (NFB) at the defect bottom and OLP-seeded HYDR also within the scaffold area, whereas PLGA-scaffolds showed lower rates. The relative density of NFB was markedly higher in the HYDR/OLB group compared to the corresponding PLGA group. TCP/Col had good stiffness to prepare complex structures by bioplotting but HYDR and PLGA were very soft. HYDR showed appropriate biodegradation, TCP/Col and PLGA seemed to be nearly undegraded after 14 weeks. 3D-bioplotted, cell-seeded HYDR and TCP/Col scaffolds increased the amount of NFB within ovine critical-size calvarial defects, but stiffness, respectively, biodegradation of materials is not appropriate for the application in cranio-facial surgery and have to be improved further by modifications of the manufacturing process or their material composition.

Accelerated angiogenic host tissue response to poly(L-lactide-co-glycolide) scaffolds by vitalization with osteoblast-like cells.

BACKGROUND: Bone substitutes should ideally promote rapid vascularization, which could be accelerated if these substitutes were vitalized by autologous cells. Although adequate engraftment of porous poly(L-lactide-co-glycolide) (PLGA) scaffolds has been demonstrated in the past, it has not yet been investigated how vascularization is influenced by vitalization or, more precisely, by seeding PLGA scaffolds with osteoblast-like cells (OLCs). For this reason, we conducted an in vivo study to assess host angiogenic and inflammatory responses after the implantation of PLGA scaffolds vitalized with isogeneic OLCs. MATERIALS AND METHODS: OLCs were seeded on collagen-coated PLGA scaffolds that were implanted into dorsal skinfold chambers in BALB/c mice (n = 8). Two further groups of animals received either collagen-coated (n = 8) or uncoated PLGA scaffolds (n = 8). Animals that received chambers without implants served as controls (n = 8). Angiogenesis, neovascularization, and leukocyte-endothelial cell interaction were analyzed for 14 days using intravital fluorescence microscopy. RESULTS: PLGA scaffolds with and without OLCs showed a temporary increase in leukocyte recruitment. At day 3 after implantation, a marked angiogenic host tissue response was observed in close vicinity of all scaffolds studied. At days 6 and 10, the angiogenic response was significantly higher (p < 0.05) in PLGA scaffolds vitalized with OLCs than in uncoated or collagen-coated PLGA scaffolds. The majority of OLCs, however, died within 14 days after implantation. CONCLUSION: Our study demonstrates that PLGA scaffold vitalization with OLCs accelerates the angiogenic response in the surrounding host tissue. Bone substitutes created by tissue engineering may thus be superior to nonvitalized substitutes although the seeded cells do not survive for long periods.

Serratus anterior free flap in oral reconstruction.

PURPOSE: Perforating oral and maxillofacial defects frequently cause severe functional disorders. Microvascular free flaps like the radial forearm flap and the latissimus dorsi flap have been described to cover those defects; however, harvest of the radial forearm flap causes remarkable donor-site morbidity, while the latissimus dorsi flap often turns out to be too bulky. Therefore we introduce the serratus anterior muscle as a versatile and reliable microvascular flap to cover defects of both the floor of the mouth and the maxilla. PATIENTS AND METHODS: Between 2003 and 2007, 10 oral defects were reconstructed using the serratus anterior flap. In 5 of the cases, the defects were located at the hard palate and maxilla, while in the other cases they were located in the floor of the mouth. RESULTS: All of the patients were able to feed orally within the first week postoperatively. Donor-site morbidity was observed to be negligible not least because of the achievement of primary tension-free wound closure. Successful reconstruction could be observed in 8 of 10 patients. CONCLUSION: Although the serratus anterior muscle flap lacks an epithelial layer, this flap is not restricted to a subcutaneous placement. Due to rapid epithelialization, the serratus anterior muscle is even suitable for perforating intraoral defects.

Consequences of seeded cell type on vascularization of tissue engineering constructs in vivo.

Implantation of tissue engineering constructs is a promising technique to reconstruct injured tissue. However, after implantation the nutrition of the constructs is predominantly restricted to vascularization. Since cells possess distinct angiogenic potency, we herein assessed whether scaffold vitalization with different cell types improves scaffold vascularization. 32 male balb/c mice received a dorsal skinfold chamber. Angiogenesis, microhemodynamics, leukocyte-endothelial cell interaction and microvascular permeability induced in the host tissue after implantation of either collagen coated poly (L-lactide-co-glycolide) (PLGA) scaffolds (group 4), additionally seeded with osteoblast-like cells (OLCs, group 1), bone marrow mesenchymal stem cells (bmMSCs, group 2) or a combination of OLCs and bmMSCs (group 3) were analyzed repetitively over 14 days using intravital fluorescence microscopy. Apart from a weak inflammatory response in all groups, vascularization was found distinctly accelerated in vitalized scaffolds, indicated by a significantly increased microvascular density (day 6, group 1: 202+/-15 cm/cm(2), group 2: 202+/-12 cm/cm(2), group 3: 194+/-8 cm/cm(2)), when compared with controls (group 4: 72+/-5 cm/cm(2)). This acceleration was independent from the seeded cell type. Immunohistochemistry revealed in vivo VEGF expression in close vicinity to the seeded OLCs and bmMSCs. Therefore, the observed lack of cell type confined differences in the vascularization process suggests that the accelerated vascularization of vitalized scaffolds is VEGF-related rather than dependent on the potential of bmMSCs to differentiate into specific vascular cells.

Five-year retrospective study of mandibular fractures in Freiburg, Germany: incidence, etiology, treatment, and complications.

PURPOSE: To evaluate current trends in maxillofacial trauma, a retrospective review of mandibular fractures at a German university hospital was carried out. PATIENTS AND METHODS: In this retrospective study, records of 444 patients with mandibular fractures between 2000 and 2005 at the Department of Oral and Maxillofacial Surgery, University Hospital of Freiburg, Germany, were reviewed. A total of 444 patients presented with 696 mandibular fractures. RESULTS: Three hundred twenty-nine (74%) of the fractures occurred in male and 115 (26%) in female patients (2.9:1). One hundred forty-two fractures (32%) resulted from road traffic accidents, 126 from fights (28%), and 116 from falls (26%). Forty-four fractures were caused by sport accidents (10%) and 16 by pathologic fractures (4%). The mandibular condyle area was the most common fracture site, with 291 fractures (42%), followed by 144 fractures of the symphyseal and parasymphyseal area (21%) and 141 angle fractures (20%). Combined fractures were found in nearly half of the cases. Five hundred seventy-nine (83%) of patients with mandibular fractures were treated by surgical intervention, 117 (17%) of patients conservatively. Regarding the surgical treatment, 561 (65%) miniplates, 247 (29%) locking plates, and 51 (6%) lag screws were used. Complications, such as postoperative infections, abscesses, and osteomyelitis appeared in 66 (9%) cases. CONCLUSION: We concluded that osteosynthesis of mandibular fractures by miniplates and locking plates are both reliable.

Influence of different types of guns, projectiles, and propellants on patterns of injury to the viscerocranium.

PURPOSE: Gunshot injuries to the oral and craniomaxillofacial region vary with the type of gun used. Computed tomography (CT) is the standard diagnostic tool for assessing tissue damage in patients with gunshot injuries. Cone-beam computed tomography (CBCT) is a new imaging technique that has recently become available for clinical diagnosis. The objective of this study was to characterize injury patterns with a focus on gun types and identify the imaging modality that is best suited to assessing injuries caused by different gun types. PATIENTS AND METHODS: We present the cases of 14 patients who sustained gunshot injuries to the viscerocranium during the past 10 years. The injuries were caused by 8 basic combinations of handguns or long guns with soft lead core projectiles, partial or full metal-jacketed bullets, and different propellants. Diagnosis was based on clinical and radiological findings (including CT and CBCT). RESULTS: We found a direct correlation between the gun/projectile combination on the one hand and the diameter of the wound track, tissue contamination, and tissue destruction on the other. Entrance and exit wounds are indicative of certain gun/projectile combinations. High-density projectiles cause severe artifacts in CT, unlike CBCT, making it difficult to evaluate anatomic structures in close proximity to the projectile. CONCLUSIONS: Every gun/projectile combination is associated with a typical pattern of injury. Even in the absence of the offending projectile, it is thus possible to narrow down the likely gun and/or projectile. In the diagnostic imaging of injuries caused by high-density projectiles, CBCT is more suitable than CT.

Osseous alterations at the interface of hydrogel expanders and underlying bone.

INTRODUCTION: In plastic and reconstructive surgery, self-activating hydrogel expanders are used to augment soft-tissue space. The purpose of this study was to investigate the morphological response of underlying bone to the constant pressure exerted by a hydrogel expander. METHODS: Eighteen Lewis rats were randomly divided into three groups. In group 1, a hydrogel expander was placed subperiosteally directly onto the calvaria of the rats. In group 2, the expander and the underlying bone were separated by a polydioxanone (PDS) foil. Group 3 animals served as controls. Before and 14 days after the insertion of the expanders, micro-computed tomography (CT) images were obtained and fused. We analysed hydroxyapatite density beneath and at the periphery of the expander and performed a histomorphometric bone analysis. RESULTS: Whereas there were no significant differences (p<0.05) (groups 1 and 2) in bone density at the periphery of the expanders between the study groups, a significant decrease in hydroxyapatite density beneath the expanders was observed in those animals in which the devices were placed directly onto the calvaria (group 1). Whereas bone thickness was unaffected at the periphery of the expanders in all groups, it was significantly decreased beneath the expanders in all implanted animals. A morphological examination revealed resorption lacunae with a diameter of 218.4+/-56 mICROm in those rats in which the expanders had been placed directly onto the calvaria. CONCLUSION: This study shows the direct influence of hydrogel expanders on underlying bone. Whereas bone resorption and connective tissue formation also occur underneath hydrogel expanders, these effects can be avoided if the expander and the underlying bone are separated by PDS foil. The key to success is to ensure the appropriate placement of expanders and thus to avoid bone resorption.

Speech and swallowing impairment after treatment for oral and oropharyngeal cancer.

OBJECTIVES: To assess the prevalence of speech and swallowing impairment after radical surgery for oral and oropharyngeal cancer from the patient's viewpoint and to examine the association of these functional alterations with selected clinical characteristics regarding patients, tumors, and oncologic treatment. DESIGN: Cross-sectional, multicenter study using a self-administered questionnaire. SETTING: Forty-three hospitals in Germany, Switzerland, and Austria. PATIENTS: A total of 3894 questionnaires about rehabilitation problems after treatment for oral and oropharyngeal squamous cell carcinoma were sent to patients. Of these, 1652 were filled out and returned, and 1334 (80.8%) met the inclusion criteria. MAIN OUTCOME MEASURES: Morbidity associated with treatment of oral and oropharyngeal cancer. RESULTS: Speech problems were reported by 851 patients (63.8%), and swallowing problems were reported by 1006 patients (75.4%). The variables that presented a significant association with speech and swallowing impairment were sex, tumor location, pTNM stages, stage of tumor, treatment modality, and reconstruction type. CONCLUSIONS: This survey, based on patient perception, suggests that those who undergo radiotherapy associated with the surgical removal of a tumor, have late-stage tumors (III-IV), or have tumors located in the floor of the mouth should be informed of the greater risk of persistent severe speech and swallowing problems.

[Necrotizing sialometaplasia: diagnosis of a rare entity]. / Die nekrotisierende Sialometaplasie: Diagnostik einer seltenen Entität.

A differential diagnosis of an ulcer on the hard palate must consider a wide variety of diseases and conditions, among them rare entities such as necrotizing sialometaplasia. We report the case of a patient who presented with a painful ulcer on the hard palate. A biopsy taken at the initial presentation of the patient revealed a diagnosis of necrotizing sialometaplasia. Histology showed foci of eosinophilic granulocytes with lobular infarction or necrosis, bland-appearing nuclear morphology of squamous cells, simultaneous metaplasia of ducts and mucous acini. The ulcer resolved spontaneously within seven weeks and required no specific treatment. The case presented here shows that early diagnosis of necrotizing sialometaplasia is important in order to prevent unnecessary treatment.