Dependence of odontogenic abscess on meteorological parameters: truth or myth?

OBJECTIVES: It is still a common belief among dental practitioners that odontogenic abscesses are somehow linked to meteorological parameters. We investigated the influence of different meteorological parameters on the type of surgical abscess treatment (intra- versus extraoral incision) as a measure of the weather-dependent severity of infection. MATERIALS AND METHODS: In this retrospective cohort study, we analyzed 841 patients who presented at our outpatient clinic with an odontogenic abscess between 2004 and 2013. RESULTS: We found no statistical dependence between intra- versus extraoral abscess incision with regard to temperature, atmospheric pressure, or relative air humidity. The annual distribution of abscesses was even, and the number of abscesses with greater or lesser mean values of each meteorological parameter did not differ significantly. CONCLUSIONS: Our results showed no statistical relationship between meteorological parameters and intra- or extraoral abscess incisions. CLINICAL RELEVANCE: Our analysis supports the assumption that the theorized relationship between odontogenic abscesses and meteorological parameters remains a myth.

Systemic sclerostin antibody treatment increases osseointegration and biomechanical competence of zoledronic-acid-coated dental implants in a rat osteoporosis model.

Osseointegration of dental implants can be promoted by implant-surface modifications using bisphosphonate coatings. In addition, it is of clinical interest to promote peri-implant bone formation and to restore bony structure in low bone-mass patients. The present study evaluated a combination of an anti-resorptive zoledronic acid (ZOL) implant-coating and a systemically applied sclerostin antibody, a known bone anabolic treatment principle, versus sole sclerostin antibody treatment or ZOL implant-coating in a rat osteoporosis model. Uncoated reference surface implants or ZOL-coated implants (n = 64/group) were inserted into the proximal tibia of aged osteoporotic rats three months following ovariectomy. 32 animals of each group received once weekly sclerostin antibody therapy. Osseointegration was assessed 2 or 4 weeks post-implantation by ex vivo µCT, histology and biomechanical testing. Overall implant survival rate was 97 %. Histomorphology revealed pronounced bone formation along the entire implant length of ZOL-coated implants. At 4 weeks following implant insertion, bone-implant contact, cancellous bone mineral density and bone volume/tissue volume were significantly increased for the combination of ZOL and sclerostin antibody as compared to sclerostin antibody or ZOL implant-coating alone. Removal torque was also significantly increased in the combination therapy group relative to animals receiving only sclerostin antibody therapy or ZOL-coated implants. In an osteoporotic rat model, the combination of anti-resorptive ZOL implant-coating and systemically applied sclerostin antibody led to significantly increased peri-implant bone formation. Therefore, the combination of ZOL and the osteoanabolic sclerostin antibody was more effective than either agent alone.

Osseointegration of biochemically modified implants in an osteoporosis rodent model.

The present study examined the impact of implant surface modifications on osseointegration in an osteoporotic rodent model. Sandblasted, acid-etched titanium implants were either used directly (control) or were further modified by surface conditioning with NaOH or by coating with one of the following active agents: collagen/chondroitin sulphate, simvastatin, or zoledronic acid. Control and modified implants were inserted into the proximal tibia of aged ovariectomised (OVX) osteoporotic rats (n = 32/group). In addition, aged oestrogen competent animals received either control or NaOH conditioned implants. Animals were sacrificed 2 and 4 weeks post-implantation. The excised tibiae were utilised for biomechanical and morphometric readouts (n = 8/group/readout). Biomechanical testing revealed at both time points dramatically reduced osseointegration in the tibia of oestrogen deprived osteoporotic animals compared to intact controls irrespective of NaOH exposure. Consistently, histomorphometric and microCT analyses demonstrated diminished bone-implant contact (BIC), peri-implant bone area (BA), bone volume/tissue volume (BV/TV) and bone-mineral density (BMD) in OVX animals. Surface coating with collagen/chondroitin sulphate had no detectable impact on osseointegration. Interestingly, statin coating resulted in a transient increase in BIC 2 weeks post-implantation; which, however, did not correspond to improvement of biomechanical readouts. Local exposure to zoledronic acid increased BIC, BA, BV/TV and BMD at 4 weeks. Yet this translated only into a non-significant improvement of biomechanical properties. In conclusion, this study presents a rodent model mimicking severely osteoporotic bone. Contrary to the other bioactive agents, locally released zoledronic acid had a positive impact on osseointegration albeit to a lesser extent than reported in less challenging models.

Paediatric gingival extra-axial chordoma: an extremely rare entity.

Extra-axial chordomas are rare malignant tumours. As a subcategory of axial chordomas, these tumours arise outside the axial skeleton. This report describes the case of a 13-year-old male patient with a gingival mass in the left upper jaw, who was referred to Hannover Medical School with a preliminary diagnosis of a calcifying epithelial odontogenic tumour (CEOT). Pathological examination of the enucleated tumour led to the final diagnosis of a chordoma. Thereafter, a stepwise radical resection was performed with the aim of complete resection of the tumour with wide safety margins. The main tumour mass was found to be located on the maxillary gingiva, with focal infiltration into the maxillary bone. Following resection, reconstruction was performed with a free latissimus dorsi flap. Follow-up after 1 year revealed no signs of recurrence or metastasis. This case highlights that although extremely rare, extra-axial chordoma may occur at sites distant from the midline and as such must be included in the differential diagnosis of bone and soft tissue tumours in the maxillofacial region.

Cleft lip and palate: the psychological burden of affected parents during the first three years of their children's lives.

The surgical treatment of cleft lip and palate (CLP) has been well described in the literature. Nevertheless, little is known about the psychological burden of affected parents. The aim of this study was to investigate the psychological burden in parents of children with CLP within the first 3 years of the children's lives. A standardized questionnaire (Parenting Stress Index, PSI) was administered to 33 parents of children with CLP to evaluate their psychological burden. The corresponding interview was conducted independent of any operative procedure during the yearly routine CLP consultation. Each participant's stress profile was assessed and compared with the average values of parents with non-cleft children. Psychological stress was substantially increased in all participants when compared to the parents of healthy children. This result was highly significant (P < 0.001). Parent depression (P < 0.001) and child-related requirements (P < 0.001) were the most critical subscales in the stress profile. Overall, the child-related burden was greater than the parent-related burden. These results indicate that parents of children with CLP have a higher level of psychological stress than parents of non-cleft children. This psychological stress might be reduced if addressed by specialist clinical psychologists in cleft-treating centres.

Quantitative analysis of soft tissue sagging after lateral midface fractures: A 10-year retrospective study.

BACKGROUND: Lateral midface fractures occasionally require open reduction and internal fixation to restore function and facial symmetry. However, some patients retain facial asymmetry despite undergoing surgery due to hard tissue displacement or soft tissue sagging. This study aimed to determine the influence of soft tissue sagging on the postoperative facial symmetry. METHODS: We examined the medical records of 590 patients who underwent planned plate removal after lateral midface or zygomatic bone fractures. After applying the inclusion and exclusion criteria, we analyzed 106 cases of lateral midface fractures for hard tissue displacement and soft tissue sagging using pre- and postoperative radiological imaging and postoperative face scanning. RESULTS: We observed significantly larger soft tissue sagging (p < 0.001) and hard tissue displacement (p = 0.006) on the fractured side than on the non-fractured side. There was no correlation between differences in the soft tissue sagging and those in the hard tissue displacement (|rho|=0). Linear regression analysis showed no statistical influence of sex or age group on the soft tissue sagging and hard tissue displacement. CONCLUSION: Therefore, we recommend treating soft tissue sagging as a discrete aspect of midfacial fracture treatment to achieve optimal postoperative facial symmetry. From a clinical perspective, we recommend better soft tissue management during open fracture treatment than focusing mainly on the reduction of bony hard tissues.

Oral health-related quality of life in tumour patients treated with patient-specific dental implants.

Dental rehabilitation after surgically acquired bone deficiency related to tumour treatment remains a challenge. The insertion of patient-specific implants geared to the contour of the remaining bone is a feasible method of supporting fixed or removable dentures. As oral health-related quality of life (OHRQoL) is of great interest in these cases, 12 individuals treated with patient-specific implants for severe bone deficiency were surveyed and their Oral Health Impact Profile (OHIP) scores after dental rehabilitation were evaluated. The OHIP-G53 questionnaire was used to measure overall treatment outcomes. The distribution of OHIP sum-scores for participants treated with patient-specific implants was almost homogeneous when compared to those cited in the literature for patients treated with conventional dental implants. OHIP items related to functional impairment and physical pain showed the highest scores (occurring occasionally), and financial loss related to treatment was frequently stated. Moreover, higher scores were detected in almost all OHIP dimensions for participants with patient-specific implant-supported removable dentures. Conversely, those treated with patient-specific dental implants and fixed dentures showed lower psychosocial impact scores and equal or superior OHRQoL. Hence, patient-specific dental implants, especially combined with fixed dentures, can lead to a positive OHRQoL in patients with severe bone deficiencies related to tumour therapy.

Scapula pre-augmentation in sheep with polycaprolactone tricalcium phosphate scaffolds.

A scapula free flap is a commonly used method to reconstruct intraoral defects of the mandible and maxilla. Despite its clear advantages, it shows some deficiencies concerning the amount and shape of the available bone, especially with respect to later implant placement. To overcome these limitations, we pre-augmented the scapula prior to a potential flap-raising procedure with polycaprolactone (PCL) tricalcium phosphate (TCP) scaffolds in a sheep model. In our study, the scapula angle was augmented with a block of PCL-TCP in three adult sheep. After 6 months, the amount of newly formed bone and scaffold degradation were evaluated using cone-beam computed tomography scans and histomorphometric analysis. All animals survived the study and showed no problems in the augmented regions. The scaffolds were attached firmly to the scapula and showed a bonelike consistency. A fair amount of the scaffold material was degraded and replaced by vital bone. Our method seems to be a valid approach to pre-augment the scapula in sheep. In further experiments, it will be interesting to determine whether it is possible to transplant a modified scapula flap to an intraoral defect site.

New mutants of Saccharomyces cerevisiae affected in the transport of proteins from the endoplasmic reticulum to the Golgi complex.

We have isolated new temperature-sensitive mutations in five complementation groups, sec31-sec35, that are defective in the transport of proteins from the endoplasmic reticulum (ER) to the Golgi complex. The sec31-sec35 mutants and additional alleles of previously identified sec and vacuolar protein sorting (vps) genes were isolated in a screen based on the detection of alpha-factor precursor in yeast colonies replicated to and lysed on nitrocellulose filters. Secretory protein precursors accumulated in sec31-sec35 mutants at the nonpermissive temperature were core-glycosylated but lacked outer chain carbohydrate, indicating that transport was blocked after translocation into the ER but before arrival in the Golgi complex. Electron microscopy revealed that the newly identified sec mutants accumulated vesicles and membrane structures reminiscent of secretory pathway organelles. Complementation analysis revealed that sec32-1 is an allele of BOS1, a gene implicated in vesicle targeting to the Golgi complex, and sec33-1 is an allele of RET1, a gene that encodes the alpha subunit of coatomer.

MRI and dental implantology: two which do not exclude each other.

Currently, histological techniques are used to analyse implant-tissue-interactions. However, these methods are destructive and time-consuming. Furthermore, they require a large number of animals as longitudinal observations in one individual are not possible. The evaluation by non-destructive imaging techniques provides the opportunity to study the osseous integration with a reduced number of animals and a decreased biological variability. The present study examined the suitability of magnetic resonance imaging (MRI) to assess peri-implant bone formation exemplarily for a dental implant in a minipig model. Due to its compatibility to MR imaging polyetheretherketone (PEEK) coated with a thin layer of titanium was applied as implant material. Osseointegration was analysed within different peri-implant regions quantifying bone volume density and soft tissue content, which were assessed by MRI and histology, likewise. It could be proven that the examined regions showed differences in bone formation; the region adjacent to the implant apex turned out to be the most dynamic. Both methods led to comparable results with no significant differences regarding to the assessed parameters. Moreover, it was demonstrated that titanium coated PEEK showed a sufficient osseointegration and MRI provides a promising application in monitoring bone formation.

Is lower extremity revascularization worthwhile in patients with end-stage renal disease?

BACKGROUND: The purpose of this study was to review the results of lower extremity revascularization in patients with end-stage renal disease and to determine in these patients the functional benefit and cost of an aggressive approach to limb preservation. METHODS: During a 5-year period at our institution, 33 bypass operations were performed on 31 limbs of 23 dialysis-dependent patients. Indications for revascularization were limited (18) or extensive (12) tissue loss or ischemia without tissue loss (3). Procedures included aortobifemoral bypass (1), femoropopliteal bypass (10), and femorotibial/pedal bypass (22). A digital or transmetatarsal amputation was performed in 57% of limbs. RESULTS: The 30-day primary patency was 100%. Cumulative primary and secondary patency rates at 2 years were 65% and 79%, respectively. Limb salvage was 67% and 59% at 1 and 2 years, respectively. Patient survival was poor (47% at 2 years). Peritoneal dialysis was predictive of poor survival (P <.001). Four of 5 patients on peritoneal dialysis died within 3 months of intervention. Extensive tissue loss was predictive of a diminished rate of limb salvage (P =.027). Only 39% of limbs with extensive tissue loss were salvaged at 1 year compared with 78% and 100% of limbs with limited and no tissue loss, respectively. The average hospital cost was $44,308 per year of limb salvage. CONCLUSIONS: Although revascularization of ischemic limbs in dialysis patients can be achieved with an excellent initial graft patency and reasonable limb salvage, patient survival is poor and costs are high. A selective approach to revascularization in these complicated patients may be indicated. For patients treated with peritoneal dialysis and for those with extensive tissue loss, primary amputation may be the preferred approach.

Efficacy of tissue engineered bone grafts containing mesenchymal stromal cells for cleft alveolar osteoplasty in a rat model.

UNLABELLED: The development of sufficient tissue engineered bone grafts for alveolar cleft osteoplasty could reduce the necessity of autogenous bone grafts and its donor site morbidity. The aim of the study was to evaluate tissue engineered bone grafts in an artificially created bone defect. Bone grafts were created in vitro colonizing a synthetic hydroxyapatite-tricalciumphosphate scaffold (BONITmatrix(®)) with either undifferentiated mesenchymal stromal cells (group 1) or osteogenic differentiated mesenchymal stromal cells (group 2). Cells were multiplied from bone marrow of donor rats. Unmodified scaffolds (group 3) and the tissue engineered bone grafts were inserted into artificial maxillary defects of 54 Lewis rats. In 18 animals the defects remained unfilled (control). After one, three and six weeks the rats were sacrificed. The defect was evaluated radiologically and histologically with regard to the remaining defect volume and diameter. Statistical analysis followed. The bone grafts led to a specific bone formation at the defect margin. No complete reunion of any defect was observed within the healing time. After six weeks, the remaining defect volume was 6.86 ± 3.21 mm(3) (control), 4.08 ± 1.36 mm(3) (group 1), 5.00 ± 0.84 mm(3) (group 2) 5.50 ± 1.05 mm(3) (group 3). The remaining defect diameter measured 2.63 ± 0.52 mm (control), 2.39 ± 0.23 mm (group 1), 2.53 ± 0.22 mm (group 2) and 2.70 ± 0.66 mm (group 3). In all experimental groups the defect volume and diameter decreased over time, which was significant for group 1 (p = 0.014), group 2 (p = 0.025) and group 3 (p = 0.048). The defect volume and width was significantly reduced for bone grafts containing undifferentiated cells compared to control (p = 0.035) or scaffolds only (p = 0.05). CONCLUSION: Tissue engineered bone grafts induce a pronounced bone formation in artificial bone defects compared to unfilled controls or scaffolds only.

Chondroitin sulfate and sulfated hyaluronan-containing collagen coatings of titanium implants influence peri-implant bone formation in a minipig model.

An improved osseous integration of dental implants in patients with lower bone quality is of particular interest. The aim of this study was to evaluate the effect of artificial extracellular matrix implant coatings on early bone formation. The coatings contained collagen (coll) in conjunction with either chondroitin sulfate (CS) or sulfated hyaluronan (sHya). Thirty-six screw-type, grit-blasted, and acid-etched titanium implants were inserted in the mandible of 6 minipigs. Three surface states were tested: (1) uncoated control (2) coll/CS (3) coll/sHya. After healing periods of 4 and 8 weeks, bone implant contact (BIC), bone volume density (BVD) as well as osteoid related parameters were measured. After 4 weeks, control implants showed a BIC of 44% which was comparable to coll/CS coated implants (48%) and significantly higher compared to coll/sHya coatings (37%, p = 0.012). This difference leveled out after 8 weeks. No significant differences could be detected for BVD values after 4 weeks and all surfaces showed reduced BVD values after 8 weeks. However, at that time, BVD around both, coll/CS (30%, p = 0.029), and coll/sHya (32%, p = 0.015), coatings was significantly higher compared to controls (22%). The osteoid implant contact (OIC) showed no significant differences after 4 weeks. After 8 weeks OIC for controls was comparable to coll/CS, the latter being significantly higher compared to coll/sHya (0.9% vs. 0.4%, p = 0.012). There were no significant differences in osteoid volume density. In summary, implant surface coatings by the chosen organic components of the extracellular matrix showed a certain potential to influence osseointegration in vivo.

Assessment of endogenous dopamine release by methylphenidate challenge using iodine-123 iodobenzamide single-photon emission tomography.

This double-blind, placebo-controlled study assessed pharmacologically induced endogenous dopamine (DA) release in healthy male volunteers (n=12). Changes in endogenous DA release after injection of the psychostimulant drug methylphenidate were evaluated by single-photon emission tomography (SPET) and constant infusion of iodine-123 iodobenzamide ([123I]IBZM), a D2 receptor radioligand that is sensitive to endogenous DA release. Methylphenidate induced displacement of striatal [123I]IBZM binding, resulting in a significantly decrease in the specific to non-specific [123I]IBZM uptake ratio (average: 8.6%) in comparison with placebo (average: -1.9%). Moreover, injection of methylphenidate induced significant behavioural responses on the following items: excitement, anxiety, tension, and mannerisms and posturing. The results of this study demonstrate the feasibility of using constant infusion of [123I]IBZM and SPET imaging to measure endogenous DA release after methylphenidate challenge and to investigate neurochemical aspects of behaviour.

[Idiopathic pulmonary hemosiderosis and Goodpasture's syndrome -- radiological findings (author's transl)]. / Das Lungenbild bei genuiner Haemosiderose und Goodpasture-Syndrom

Description of roentgenographic changes in idiopathic pulmonary hemosiderosis and Goodpasture's syndrome. Diagnostic criteria for differentiation from alveolar edema are shown. Separation of disseminated alveolar infections without clinical information is not possible. The close relation to idiopathic pulmonary hemosiderosis and Goodpasture's syndrome is emphasized.

The cost-effectiveness of repairing ruptured abdominal aortic aneurysms.

BACKGROUND: Although advances in technology have reduced the operative risk of elective abdominal aortic aneurysm (AAA) repair, the surgical repair of ruptured AAAs is associated with a much poorer prognosis and a higher cost. Accordingly, it has been suggested that patients with predictably high rates of morbidity and mortality from ruptured AAA may not benefit from surgical intervention. METHODS AND RESULTS: A cost-effectiveness analysis was performed with the use of a Markov decision-analytic model to compute long-term survival in quality-adjusted life years and lifetime costs for a hypothetical cohort of patients with ruptured AAAs managed with either a strategy of open surgical repair or no intervention. Probability estimates for the various outcomes were based on a review of the literature. Average costs of (1) the immediate hospitalization ($28,356) and (2) complications resulting from the procedure were based on the average use of resources as reported in the literature and from a hospital's cost accounting system. Our measure of outcome was the incremental cost-effectiveness ratio. For our base-case analysis, the repair of ruptured AAAs was cost-effective with an incremental cost-effectiveness ratio of $10,754. (Society is usually willing to pay for interventions with cost-effectiveness ratios of less than $60,000; for example, the costeffectiveness ratios for coronary artery bypass grafting and dialysis are $9500 and $54,400, respectively.) In sensitivity analyses, the cost-effectiveness of repairing ruptured AAAs was influenced only by alterations in the operative mortality. If the operative mortality exceeded 88%, repair of ruptured AAAs was no longer cost-effective. As an independent variable, increasing age had no substantial impact on the cost-effectiveness, although it is reported to be associated with increased operative mortality. It was necessary that the patient's cost of the initial hospitalization for ruptured AAA exceed $195,000 before repairing ruptured AAAs was no longer cost-effective. CONCLUSIONS: Our analysis suggests that despite the high cost and poor outcomes, the surgical repair of ruptured AAAs is still cost-effective when compared with no intervention. The cost of repairing ruptured AAAs falls within society's acceptable limits and therefore should not be a consideration in the management of patients with AAAs.

[Multiple nodular densities on chest X-ray in liver cirrhosis--a diagnostic problem? (author's transl)]. / Multiple pulmonale Rundherde bei Leberzirrhose--ein diagnostisches Problem

A case report is given of a 49 year old white male patient, who had suffered for several years from liver cirrhosis and who finally died from hepatoma. Although a hepatoma was suspected in this case it was not demonstrated intra vitam, though at autopsy it was found to have invaded the lower vena cava, continuing into the right atrium. Problems of early diagnosis of hepatoma are discussed in context with this case.