[Update 2022: interdisciplinary statement on airway management with supraglottic airway devices in pediatric emergency medicine-The laryngeal mask is and remains state of the art : Joint statement of the Institute for Emergency Medicine and Medicine Management (INM), the University Clinic Munich, LMU Munich, Germany, the Working Group for Pediatric Critical Care and Emergency Medicine of the German Interdisciplinary Society for Critical Care and Emergency Medicine (DIVI), the Medical Directors of Emergency Medical Services in Bavaria (ÄLRD), the Scientific Working Group for Pediatric Anesthesia (WAKKA) of the German Society for Anesthesiology and Intensive Care Medicine (DGAI), the Scientific Working Group for Emergency Medicine of the German Society for Anesthesiology and Intensive Care Medicine (DGAI) and the Society of Neonatology and Pediatric Critical Care Medicine (GNPI)]. / Update 2022: Interdisziplinäre Stellungnahme zum Atemwegsmanagement mit supraglottischen Atemwegshilfen in der Kindernotfallmedizin ­ die Larynxmaske ist und bleibt State of the Art : Gemeinsame Stellungnahme des Instituts für Notfallmedizin und Medizinmanagement (INM), Klinikum der Universität München, der Sektion Pädiatrische Intensiv- und Notfallmedizin der Deutschen Interdisziplinären Vereinigung für Intensiv- und Notfallmedizin (DIVI), des Ärztlicher Leiter Rettungsdienst Bayern (ÄLRD Bayern), des Wissenschaftlichen Arbeitskreises Kinderanästhesie (WAKKA) der Deutschen Gesellschaft für Anästhesiologie und Intensivmedizin (DGAI), des Wissenschaftlichen Arbeitskreises Notfallmedizin der Deutschen Gesellschaft für Anästhesiologie und Intensivmedizin (DGAI) und der Gesellschaft für Neonatologie und Pädiatrische Intensivmedizin (GNPI).

BACKGROUND: Airway management with supraglottic airway devices (SGA) in life-threatening emergencies in children is increasingly being used. Different specifications of laryngeal masks (LM) and the laryngeal tube (LT) are commonly used devices for this purpose. We present a literature review and interdisciplinary consensus statement of different societies on the use of SGA in pediatric emergency medicine. MATERIAL AND METHODS: Literature review in the PubMed database and classification of studies according to the criteria of the Oxford Centre for Evidence-based Medicine. Levels and consensus finding within the group of authors. RESULTS: The evidence for successful applications of the various types of LM is significantly higher than for LT application. Reported smaller series of successful applications of LT are currently limited to selected research groups and centers. Especially for children below 10 kg body weight there currently exists insufficient evidence for the successful application of the LT and therefore its routine use cannot be recommended. SGAs used for emergencies should have a gastric drainage possibility. DISCUSSION: Considering the scientific data and the large clinical experience with the LM in medical routine and emergency situations in children currently only the LM can be recommended for alternative (i.e., non-intubation) emergency airway management in children. If alternative airway management is part of a local emergency strategy, the LM should be provided in all pediatric sizes (1, 1½, 2, 2½, 3) for out of hospital use and in hospital emergency use and all users should regularly be trained in its application.

Biomechanical Analysis of Ideal Knee Flexion Angle for ACL Graft Tensioning Utilizing Multiple Femoral and Tibial Tunnel Locations.

Anterior cruciate ligament (ACL) graft failure rate has been reported to be greater than 5% at 5 years. Our study evaluated ACL excursion with anatomic and nonanatomic femoral and tibial tunnels to determine optimal flexion angle to tension the ACL to minimize excursion. Ten cadaveric knee specimens were used. The ACL was sectioned and the femoral and tibial attachments were marked. A 1/16-inch drill created a tunnel in the center of the ACL footprint on the tibia and femur and additional tunnels were made 5 mm from this. A suture was passed through each tunnel combination and attached to a string potentiometer. The knee was ranged from full extension to 120 degrees of flexion for 10 cycles while mounted in a custom fixture. The change in length (excursion) of the suture during movement was recorded for each combination of femoral and tibial tunnels. Anatomic reconstruction of the ACL with tunnel placement in the center of the femoral and tibial footprint did not result in an isometric graft, with excursion of the ACL during knee motion of 7.46 mm (standard deviation [SD]: 2.7mm), greatest at 2.84 degrees of flexion (SD: 4.22). The tunnel combination that resulted in the least excursion was a femoral footprint 5 mm anterior to the femoral and 5 mm posterior to the tibial footprint (4. 2mm, SD: 1.37 mm). The tunnel combination that resulted in the most excursion utilized femoral footprint 5 mm proximal to the femoral and 5 mm posterior to the tibial footprint (9.81 mm, SD: 2.68 mm). Anatomic ACL reconstruction results in significant excursion of the ACL throughout motion. If not tensioned properly, the ACL can stretch during range of motion, potentially leading to rerupture. To prevent stretching of the graft, the current biomechanical study recommends tensioning an anatomic ACL reconstruction at its point of maximal excursion, or between 0 and 5 degrees of flexion. The level of evidence is IV.

Stress Radiography Is a Reliable Method to Quantify Posterior Cruciate Ligament Insufficiency: A Systematic Review.

Purpose: To perform a systematic review of posterior tibial stress radiography techniques and radiographic measurement methods to compare their accuracy and efficacy to aid clinicians in quantifying posterior cruciate ligament laxity. Methods: Electronic databases, including PubMed, MEDLINE, Embase.com 1947- , Ovid Medline 1946- , Scopus 1823- , Cochrane Central Register of Controlled Trials (CENTRAL), and Clinicaltrials.gov 1997- were queried in December 2020. The abstracts of articles were reviewed by 2 authors for published studies comparing posterior tibial stress radiography techniques, describing, and comparing radiographic measurement methods, and comparing stress radiographs with instrumented knee testing. Results: The systematic review included 13 studies that satisfied the inclusion and exclusion criteria. There were 3 studies comparing stress radiography with instrumented knee devices, 6 studies comparing stress radiography techniques, and 5 studies evaluating the reliability of radiographic measurements. Stress radiography was more sensitive for detecting posterior tibial translation than KT-1000 and KT-2000 and was similar to the Rolimeter knee arthrometer. The majority of studies found TELOS stress radiography to be more sensitive than gravity or hamstring contraction stress views. Kneeling stress radiographs were found to be equivalent to TELOS in one study and superior in another. All reported methods of radiographic measurement for posterior tibial translation showed good-to-excellent intraobserver and interobserver reliability, and no single technique demonstrated clear superiority. Conclusions: The results of this systematic review indicate that posterior stress radiography with TELOS and kneeling stress radiography are the most reliable methods to evaluate posterior cruciate ligament laxity. Gravity stress and hamstring contraction can be used but may underestimate posterior tibial translation. Radiographic measurement methods are reliable and no single method is clearly superior. Clinical Relevance: This information will allow clinicians to use various radiographic methods to objectively measure posterior tibial translation to formulate a treatment plan.

Global Variation in Studies of Articular Cartilage Procedures of the Knee: A Systematic Review.

OBJECTIVE: The objective of this study was to determine whether there are significant differences in terms of indications, techniques, patient variables, and objective and subjective outcome scores as a function of the geographic locale of published studies of knee articular cartilage surgery. METHODS: An electronic database search was performed of clinical studies evaluating knee articular cartilage procedures from 2000 to 2021. Studies were separated into global regions (Europe, Asia, North America, and South America) based on the study country. All cartilage-based treatments in each region were recorded. Patient age and sex, mechanism of injury, cartilage lesion size and location, follow-up time, failure rate, and knee outcome scores utilized were summarized and compared by region. RESULTS: A total of 2,923 studies were analyzed. Eighty level 1 and 2 studies met the inclusion criteria. The majority were from Europe (n = 60), followed by Asia (n = 11), North America (n = 7), and South America (n = 2). The majority of procedures in European and North American studies were cell-based and marrow-stimulation procedures. In Asian studies, the most common procedures were marrow-stimulation, experimental, and biologic procedures as defined by the authors. Asian countries had a higher proportion of females (P < 0.001) and an overall older patient population (P < 0.001). Regional variation was also seen in terms of lesion location, mechanism of injury, and failure rate. CONCLUSION: Most high-level evidence for articular cartilage-based procedures of the knee comes from European countries. These studies vary by patient age and sex, anatomic location, and mechanism of injury. Global variation should be taken into consideration when interpreting and applying studies of knee articular cartilage surgery.

Return to play following nonsurgical management of superior labrum anterior-posterior tears: a systematic review.

BACKGROUND: Superior labrum anterior-posterior (SLAP) tears are common shoulder injuries, especially in overhead athletes. Often, initial management of these injuries is nonsurgical with focused rehabilitation. The purpose of this review was to evaluate the outcomes of nonsurgical management of SLAP tears in athletes. METHODS: A systematic review was performed for articles published before March 2021 using key search terms pertaining to clinical studies evaluating the nonsurgical treatment of SLAP tears in adult patients published in English-language literature. Abstracts and manuscripts were independently reviewed by 2 co-authors to determine eligibility. Return-to-play rate and return-to-prior-athletic-performance rate were determined by combining results across studies. RESULTS: Five articles met the inclusion criteria. There were 244 total athletes (162 elite or higher-level athletes). The mean ages ranged from 20.3 to 38.0 years. Type II SLAP tears were most common; baseball, softball, and weightlifting were the most common sports involved. The return-to-play rate was 53.7% in all athletes and 52.5% in elite or higher-level athletes. In athletes who were able to complete their nonoperative rehabilitation program, the return-to-play rate was 78% in all athletes and 76.6% in elite or higher-level athletes. The overall rate of return to prior performance was 42.6%, which increased to 72% for those athletes who were able to complete their rehabilitation. Patients who discontinued the rehabilitation protocol in favor of surgery had an average of 8 physical therapy sessions compared with 20 sessions for patients with successful nonoperative treatment. The timing of return to play was generally less than 6 months in studies that reported it. Patient-reported outcomes, including the American Shoulder and Elbow Surgeons score and visual analog scale, all improved significantly after nonsurgical treatment. Factors associated with failure of nonsurgical management included older age, participation in overhead sports (especially baseball pitchers), traumatic injury, positive compression rotation test, concomitant rotator cuff injury, longer baseball career, longer symptomatic period, and the presence of a Bennett spur. CONCLUSIONS: Overall, nonoperative treatment of SLAP tears in athletes can be successful, especially in the subset of patients who are able to complete their rehabilitation program before attempting a return to play. Although nonoperative treatment should be considered the first line of treatment for most SLAP tears, there are some factors that may be associated with failure of conservative treatment; therefore, further high level, prospective studies would be beneficial to identify those athletes most likely to respond favorably to nonoperative treatment.

The Loop 'N' Tack Biceps Tenodesis: An All-Arthroscopic, Intra-Articular Technique.

Tenodesis and tenotomy of the long head of the biceps are treatment options for a wide range of pathologies without clear superior technique or site of fixation. Clinical outcomes comparing numerous techniques for tenotomy versus tenodesis have resulted in similar pain relief; however, tenotomy may result in a cosmetic "Popeye" deformity and fatigue pain. We present a quick, simple, and knotless technique for tenodesis of the long head of the biceps at the proximal aspect of the bicipital grove that can be completed entirely arthroscopically. This technique uses suture to secure a tenotomized proximal biceps tendon to a knotless anchor just proximal to the subscapularis tendon at the proximal biceps groove. The tensionless repair allows the biceps to scar within the biceps groove, thereby reducing subsidence and formation of a "Popeye" deformity and fatigue pain in the biceps seen with tenotomy alone while eliminating the ability to overtension.

The Loop 'n' Tack Knot: Biomechanical Analysis of a Novel Suture Technique for Proximal Biceps Tenodesis.

BACKGROUND: Secure tendon grasping is critical to the success of any tenodesis procedure. Several techniques currently used for tendon grasping can result in longitudinal splitting of the tendon, causing construct failure and failure of the tenodesis. PURPOSE: To compare the Loop 'n' Tack knot as a tendon-grasping technique with other common suture techniques. We investigated the biomechanical strength and mode of failure. STUDY DESIGN: Controlled laboratory study. METHODS: Eleven matched pairs of proximal biceps were harvested from fresh-frozen cadaveric shoulders. One tendon from each pair was stitched using 1 of 4 different techniques. The suture techniques evaluated included the Loop 'n' Tack with 2 different types of high-strength nonabsorbable suture, a double half-racking stitch, and a Krakow stitch. Samples were cyclically loaded between 5 and 20 N for 100 cycles, followed by a pull to failure at 33 mm/s. RESULTS: The Loop 'n' Tack techniques were equivalent to the double half-racking and Krakow techniques for load to ultimate failure (P = .817 and P = .984, respectively). The double half-racking technique was the stiffest construct, which was significantly greater than the second-stiffest group, the Loop 'n' Tack method with both FiberLink suture (P = .012) and SutureTape (P = .002), which had greater stiffness than the Krakow group (P < .001). The most common failure mode for the Loop 'n' Tack stitch was suture breakage compared with the Krakow and double half-racking methods, where the most common mode of failure was suture pullout from the tendon (P < .001). CONCLUSION: Biomechanical testing found that the Loop 'n' Tack techniques had similar ultimate load to failure values when compared with the double half-racking and Krakow methods. Mode-of-failure analysis showed that the Loop 'n' Tack construct typically failed by suture breakage, whereas the other techniques failed by suture pullout. CLINICAL RELEVANCE: The Loop 'n' Tack technique allows for secure grasping of tissue without the need for externalization of the tendon. This technique may be beneficial in compromised or poor-quality tissue without reducing overall pullout strength when compared with a standard half-racking or Krakow stitch.

Biomechanical Response to Distraction of Hip Capsular Reconstruction With Human Acellular Dermal Patch Graft.

PURPOSE: To quantify the biomechanical properties of the hip capsule with human dermal allograft reconstruction to determine whether a dermal patch restored capsular resistance to distraction. METHODS: Nine cadaveric hip specimens were dissected until capsule and bony structures remained and were then mounted in a testing fixture in neutral flexion and abduction. Four states of the hip capsule were sequentially tested under axial distraction of 5 mm measured with video analysis and with resultant force measurement: (1) intact hip capsule, (2) interportal capsulotomy, (3) capsulectomy to the zona orbicularis, and (4) capsular reconstruction with human dermal allograft using acetabular anchors and capsule-to-patch sutures. RESULTS: Capsulectomy was different from intact (P = .036), capsulotomy differed from capsulectomy (P = .012), and the repair was statistically significantly different from capsulectomy (P = .042); intact and reconstructed cases were not statistically significantly different. The force required for 5 mm of distraction decreased after interportal capsulotomy by an average of 9% compared with the intact state and further decreased after capsulectomy by 30% compared with the intact state. After capsular reconstruction using dermal allograft, force requirements increased by an average of 36% from the capsulectomy state, only 5% below the intact state. CONCLUSIONS: Human dermal allograft tissue graft provides restoration of distractive strength for use during hip capsule reconstruction with acetabular anchor fixation and distal soft-tissue fixation after capsulectomy in a cadaveric model. CLINICAL RELEVANCE: Capsular repair or reconstruction with a dermal patch offers time-zero restoration of function; intact and reconstructed cases showed no difference, and reconstruction restored a capsulectomy to a biomechanical equivalent of the intact case when distraction was applied.

Clinical performance of occlusal onlays made of lithium disilicate ceramic in patients with severe tooth wear up to 11 years.

OBJECTIVES: Evaluation of survival and complication rate of monolithic occlusal onlays made of lithium disilicate ceramic used in patients with severe tooth wear up to 11years of clinical service. METHODS: In a prospective non-randomized clinical study 7 patients (4 male, 3 female; median age: 44.3±6.56years old) were restored full mouth with a total of 103 adhesively bonded occlusal onlays made of lithium disilicate ceramic (IPS e.max Press, Ivoclar Vivadent, Schaan, Liechtenstein). All restorations were examined during annual recall visits using periodontal parameters according to the modified United States Public Health Service (USPHS) criteria: (a) marginal discoloration, (b) secondary caries, (c) marginal integrity, (d) surface texture, (e) restoration fracture, and (f) occlusal wear, rating with Alpha, Bravo and Charlie over an observation period up to 11years (68-139 months; median: 94.9±26.1 months). Data was statistically analyzed using the Kaplan-Meier estimation. RESULTS: Monolithic lithium disilicate occlusal onlays presented a 100% survival rate. Four restorations within one patient (3.9%) presented marginal discoloration, one after 60 and three after 108 months (all rated Bravo). One restoration (1%) showed a marginal crack formation (technical complication) after 120 months, rated Bravo. No biological complication, debonding or secondary caries could be found and tested periodontal parameters showed excellent results. SIGNIFICANCE: Based on the analyzed data up to 11years, monolithic occlusal onlays made of lithium disilicate ceramic can be considered as a reliable treatment option for full-mouth rehabilitations in patients with severe tooth wear.

Digital implant planning and guided implant surgery - workflow and reliability.

Modern oral implantology and implant prosthetics depend on comprehensive diagnostics and precise planning to ensure the desired outcome and meet the patient's and the dentist's expectations. In this context, digital implant planning and guided implant surgery based on three-dimensional radiographic data and the digitised intraoral surfaces can be of excellent service. They provide valuable information and permit stringent backward planning to optimise the implantological and prosthetic result, improving the safety and efficiency of the surgical procedure and rendering the restorative outcome more predictable in terms of function, biology and aesthetics. However, template-guided implant surgery carries its own specific risks in terms of manufacturing inaccuracies and application errors. These possible sources of error must be recognised and carefully considered in order to avoid adverse consequences.

Oral health-related impact profile in full-mouth restored patients with two different tooth-colored restoration materials.

OBJECTIVES: To analyze the change of oral health impact profile (OHIP) in patients with full-mouth rehabilitations due to moderate/severe tooth wear dependent on different restorative materials (ceramic/experimental CAD/CAM composite). MATERIALS AND METHODS: Twenty-nine healthy patients (15 male/14 female, age 44.6 ± 28.4 years) requiring full-mouth rehabilitation due to different degrees of tooth wear were instructed to fill the German version OHIP-G49 questionnaire before (baseline) and 30 days after prosthetic treatment with ceramic (n = 17) or experimental CAD/CAM composite (n = 12) restorations. Questions were divided into five dimensions: appearance, oral functions, psychosocial impact, linguistic limitations, and orofacial pain; changes between both OHIP-questionnaires for each question and patient were dissected by difference values, separately. Data were analyzed with the Kolmogorov-Smirnov, Wilcoxon's signed-rank, Kruskal-Wallis, Mann-Whitney, and Cronbach's alpha tests (significance level p = 0.01). RESULTS: The appearance dimension showed the highest results (p < 0.001, 100% improvement with all values > 0); the linguistic limitations dimension presented the lowest improvement (p < 0.001). The other three dimensions were not statistically different. No statistical differences between the two materials depending on OHIP questionnaire results occurred. CONCLUSIONS: The esthetic appearance of the patients was influenced positively by full-mouth rehabilitation, irrespective of the material used. Improvements were also made in the parameters "toothache" and "problem of food intake." No statements could be made for the parameter "language." CLINICAL RELEVANCE: With an increasing number of patients with moderate/severe tooth wear, thorough knowledge about the improvement of OHIP is important. This information is advantageous for the consultation and handling of patients when complex treatments are planned.

Infectious disease research and the gender gap.

Historically, women have been less likely to be supported through higher degree training programmes, and they continue to hold more junior positions in science. This paper reviews the current gender research and gender capacity-building efforts led by the UNICEF/UNDP/World Bank/WHO Special Programme for Research and Training in Tropical Diseases (TDR). Created more than 40 years ago as the only United Nations-based Special Programme dedicated to research and research capacity building on infectious diseases, TDR has a longstanding track record both in supporting research into gender-specific questions and in research capacity strengthening among women scientists. We provide an overview of these approaches, then describe a recent pilot programme on Women in Science, designed to understand and remedy the gender gaps in health research. The programme focused on Africa, but it is hoped that the replication of such schemes in TDR and other international funding agencies will lead to more attention being given to women in infectious diseases research in other continents. This article may not be reprinted or reused in any way in order to promote any commercial products or services.

Histo-anatomic 3D printing of dental structures.

The creation of dental restorations with natural appearance and biomechanics represents a major challenge for the restorative team. The manufacturing-process of high-aesthetic restorations from tooth-coloured restorative materials is currently dominated by manual manufacturing procedures and the outcome is highly dependent on the knowledge and skills of the performing dental technician. On the other hand, due to the simplicity of the manufacturing process, CAD/CAM restorations from different material classes gain more and more acceptance in the daily routine. Multi-layered restorations show significant aesthetic advantages versus monolithic ones, but are difficult to fabricate using digital technologies. The key element for the successful automated digital fabrication of aesthetic anterior restorations seems to be the form of the individual dentine core as defined by dentine enamel junction (DEJ) covered by a more transparent layer of material imitating the enamel layer to create the outer enamel surface (OES). This article describes the possibilities and technologies available for so-called '4D-printing'. It introduces the digital manufacturing process of multilayered anterior teeth using 3D multipart printing, taking the example of manufacturing replicas of extracted intact natural teeth.

Composite Resin Core Buildups With and Without Post for the Restoration of Endodontically Treated Molars Without Ferrule.

OBJECTIVE: The aim of this study was to investigate the restoration of highly damaged, broken-down endodontically treated molars without the ferrule effect using glass ceramic crowns on different dual-cure composite resin core buildups. METHODS AND MATERIALS: Thirty (N=30, n=15) decoronated, endodontically treated teeth (no ferrule) were restored without a ferrule with a direct buildup using the dual-curing composite Multicore HB (group MHB) or the dual-curing composite core buildup Multicore Flow in combination with glass-fiber-reinforced composite post (FRC post; group MFP). All teeth were prepared to receive bonded glass ceramic crowns (Empress CAD luted with Variolink II) and were subjected to accelerated fatigue testing. Cyclic isometric loading was applied to the palatal cusp at an angle of 30 degrees and a frequency of 5 Hz, beginning with a load of 200 N (×5000 cycles), followed by stages of 400, 600, 800, 1000, 1200, and 1400 N at a maximum of 30,000 cycles each. Specimens were loaded until failure or to a maximum of 185,000 cycles. Groups were compared using the life table survival analysis (log rank test at p=0.05). Average fracture loads and number of survived cycles were compared with one-way analysis of variance (Scheffé post hoc at p=0.05). Previously published data from the same authors about core buildups made of high-performance polymers (group HPP, n=15) and light-curing composite resin without FRC posts (group TEC, n=15) and with FRC posts (group TECP, n=15) using the same experimental setup were included for comparison. RESULTS: None of the tested specimen withstood all 185,000 load cycles. There was no significant difference in mean fracture load (p=0.376), survived cycles (p=0.422), and survival (p=0.613) between MHB (facture load 859.4 N±194.92) and MFP (796.13 N±156.34). Group HPP from a previous study appeared to have significantly higher performance than all other groups except MHB. All groups with posts were affected by an initial failure phenomenon (wide gap at the margin between the buildup/crown assembly and the root). CONCLUSIONS: HPP and MHB enhanced the performance of all-ceramic leucite-reinforced glass ceramic crowns, and insertion of a fiber-reinforced composite post was not influential when using other materials.

CAD/CAM Polymer vs Direct Composite Resin Core Buildups for Endodontically Treated Molars Without Ferrule.

OBJECTIVES: The aim of this study was to investigate the restoration of broken-down endodontically treated molars without ferrule effect using glass ceramic crowns on different composite resin core buildups. METHODS AND MATERIALS: Forty-five decoronated endodontically treated teeth (no ferrule) were restored with a semidirect buildup using an experimental computer-aided design/computer-aided manufacturing (CAD/CAM) high-performance polymer (HPP group) or with light-curing composite core buildups of Tetric EvoCeram with (TECP group) or without (TEC group) a glass-fiber-reinforced post. All teeth were prepared to receive bonded glass ceramic crowns (Empress CAD luted with Variolink II) and were subjected to accelerated fatigue testing. Cyclic isometric loading was applied to the palatal cusp at an angle of 30° and a frequency of 5 Hz, beginning with a load of 200 N (×5000 cycles) and followed by stages of 400, 600, 800, 1000, 1200, and 1400 N at a maximum of 30,000 cycles each. Specimens were loaded until failure or to a maximum of 185,000 cycles. Groups were compared using the life-table survival analysis (log rank test at p=0.05). Average fracture loads and number of survived cycles were compared with one-way analysis of variance (Scheffé post hoc at p=0.05). RESULTS: None of the tested specimen withstood all 185,000 load cycles. There was a significant difference in mean fracture load, survived cycles, and survival; the HPP group (fracture load 975.27N±182.74) was significantly higher than the TEC (716.87N±133.43; p=0.001) and TECP (745.67±156.34; p=0.001) groups, and the TEC and TECP groups showed no difference (p=0.884). Specimens in the TECP group were affected by an initial failure phenomenon (wide gap at the margin between the buildup/crown assembly and the root). CONCLUSIONS: Semidirect core buildup made from high-performance polymer enhanced the performance of all-ceramic leucite-reinforced glass ceramic crowns compared with direct light-curing composite resin buildups. The use of a fiber-reinforced post system did not influence the fatigue strength of all-ceramic crowns.

Intracortical remodeling parameters are associated with measures of bone robustness.

Prior work identified a novel association between bone robustness and porosity, which may be part of a broader interaction whereby the skeletal system compensates for the natural variation in robustness (bone width relative to length) by modulating tissue-level mechanical properties to increase stiffness of slender bones and to reduce mass of robust bones. To further understand this association, we tested the hypothesis that the relationship between robustness and porosity is mediated through intracortical, BMU-based (basic multicellular unit) remodeling. We quantified cortical porosity, mineralization, and histomorphometry at two sites (38% and 66% of the length) in human cadaveric tibiae. We found significant correlations between robustness and several histomorphometric variables (e.g., % secondary tissue [R(2) = 0.68, P < 0.004], total osteon area [R(2) = 0.42, P < 0.04]) at the 66% site. Although these associations were weaker at the 38% site, significant correlations between histological variables were identified between the two sites indicating that both respond to the same global effects and demonstrate a similar character at the whole bone level. Thus, robust bones tended to have larger and more numerous osteons with less infilling, resulting in bigger pores and more secondary bone area. These results suggest that local regulation of BMU-based remodeling may be further modulated by a global signal associated with robustness, such that remodeling is suppressed in slender bones but not in robust bones. Elucidating this mechanism further is crucial for better understanding the complex adaptive nature of the skeleton, and how interindividual variation in remodeling differentially impacts skeletal aging and an individuals' potential response to prophylactic treatments.

Use of a modified shell technique for three-dimensional bone grafting: description of a technique.

BACKGROUND: Defects of the alveolar crest often lead to three-dimensional bone loss after tooth extraction. Therefore, hard tissue grafting is required prior to implant placement. Different techniques have been described in the literature. METHODS: In this case report three-dimensional hard tissue grafting was performed with a modified shell technique and autogenous bone harvested from the mandibular ramus. The shells were trimmed to a thickness of 1 mm and placed to recontour the ideal shape of the alveolar ridge. The shells were then fixed with micro titanium screws, and the gap between the shells and the alveolar ridge was filled with autogenous bone chips. RESULTS: Wound healing was uneventful. Consolidation of the bone graft showed almost no resorption and the implant was placed into vital bone. CONCLUSIONS: The described shell technique for rebuilding three-dimensional alveolar defects showed promising results and could be an alternative treatment to other hard tissue grafting techniques.

Enhancing the predictability of complex rehabilitation with a removable CAD/CAM-fabricated long-term provisional prosthesis: a clinical report.

Implementing any definitive prosthetic treatment of the residual edentulous ridge involves several risks. The patient's expectations may not be completely fulfilled as such treatment procedures include major changes in function and esthetics. Innovative materials, such as high-density polymers based on a highly cross-linked polymethylmetacrylate (PMMA) or composite resin for CAD/CAM-manufacturing are an alternative treatment option. They enhance the predictability of complex rehabilitations, especially in situations where the prognosis of the residual ridge behavior over time is challenging. This article describes an innovative approach of an extended pretreatment phase by using intraoral scanning and CAD/CAM technology for the fabrication of a long-term provisional removable dental prosthesis made of high-density polymer.

Geranylgeraniol - a new potential therapeutic approach to bisphosphonate associated osteonecrosis of the jaw.

Bisphosphonate associated osteonecrosis of the jaw (BP-ONJ) is one of the main side effects of bisphosphonate therapy (BPT). To date, there is no effective therapy of the BP-ONJ. Nitrogen-containing bisphosphonates (N-BPs) are particularly able to inhibit pyrophosphate synthase (FPPS) in the mevalonate pathway (MVP). Consequent of decreased synthesis of the metabolite Geranylgeraniol (GGOH) is believed to largely account for the development of BP-ONJ. Negative effect of N-BPs could be shown, resulting in decreased viability and migration capacity of different cell types of hard and soft tissues such as osteoblasts, fibroblast und endothelial cells. Aim of our in vitro study was to demonstrate that the mevalonate pathway metabolite GGOH could reverse the negative biological effect of N-BPs. Biological effect of GGOH on bisphosphonate-treated human umbilicord vein endothelial cells (HUVEC), fibroblast and osteogenic cells was analyzed by a viability test and measuring the migration capacity in a scratch wound assay as well as a migration assay using Boyden chambers. The morphological cell architecture of the treated cells was analyzed by phallacidin staining. GGOH cell-treatment can rescue the negative effect of bisphosphonates. These results underline the hypothesis that systemic or local treatment with GGOH could lead to new therapeutic strategies for BP-ONJ.

Description and evaluation of a new approach on pre-clinical implant dentistry education based on an innovative simulation model.

INTRODUCTION: Predominantly theoretical courses are employed to teach German dental students in implant dentistry at pre-clinical stage. As implant dentistry is an important part of the clinical treatment spectra, practical implementation of this field at an early stage of education seems to be appropriate. By a newly developed interdisciplinary implant dentistry course, students should assess an improved competence level as well as first practical experiences in the field of implant dentistry at the pre-clinical stage of their education. MATERIALS AND METHODS: Interdisciplinary implant dentistry education was integrated in the final pre-clinical course Phantom II at the Department of Prosthodontics, LMU, Munich. In total 120 pre-clinical students participated at the implant dentistry education course. After theoretical introduction into implant surgery and implant prosthetics, 30 simulation units were employed for the practical training of the participants. All important treatment steps were carried out by the students under instruction by the supervisors, including interdisciplinary planning, the use of the drilling template, the template guided insertion of two implants, as well as the integration of two ball attachments into a pre-existing full denture. After the course participants were asked by questionnaire about the quality of the course and their personal opinion. RESULTS: The course received an extraordinary positive feedback. In total 108 students evaluated the course with the overall grade of 1.68 according to the German school-mark system (1 = excellent, 6 = unsatisfactory). Also the single parts of the course were voted constantly positively. CONCLUSION: The aim of this first interdisciplinary course for pre-clinical students was to enhance competence level and practical implementation of implant dentistry at an early stage of education. Participants' comments and suggestions on the questionnaires demonstrated the positive response and the general interest in this form of dental education, as well as the demand for further development of training in this field.