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L'odontome composé est une lésion constituée de tissus dentaires présentant des degrés élevés de différenciations morphologiques et histologiques. La phosphatase alcaline est une glycoprotéine qui semble etre impliquée dans le processus de minéralisation. Nous avons pratiqué I'ablation de 7 odontomes composés qui ont été traités en vue d'obtenir des coupes par usure. L'étude histologique nous a montré que les odontoblastes sont phosphatase alcaline positifs et que les cellules du stratum intermedium sont positives dans les specimens les moins bien différenciés tandis qu'ils sont négatifs dans la plupart des tumeurs différenciées. En conclusion, la positivité de 1 'activité phosphatase alcaline dans les odontomes composés peut etre probablement mise en relation avec les différents stades de formation des diverses tumeurs

PURPOSE: To compare the effectiveness of 6.0 to 8.0 mm-wide diameter implants, placed immediately after tooth extraction, with conventional 4.0 or 5.0 mm diameter implants placed in a preserved socket after a 4-month period of healing in the molar region. MATERIALS AND METHODS: Just after extraction of one or two molar teeth, and with no vertical loss of the buccal bone in relation to the palatal wall, 100 patients requiring immediate post-extractive implants were randomly allocated to immediate placement of one or two 6.0 to 8.0 mm-wide diameter implants (immediate group; 50 patients) or for socket preservation using a porcine bone substitute covered by a resorbable collagen barrier (delayed group; 50 patients), according to a parallel group design in one centre. Bone-to-implant gaps were filled with autogenous bone retrieved with a trephine drill used to prepare the implant sites for the immediate wide diameter post-extractive implants. Four months after socket preservation, one to two 4.0 or 5.0 mm-wide delayed implants were placed. Implants were loaded 4 months after placement with fixed provisional restorations in acrylic, and replaced after 4 months by fixed, definitive, metal-ceramic restorations. Patients were followed to 1 year after loading. Outcome measures were: implant failures, complications, aesthetics assessed using the pink esthetic score (PES), peri-implant marginal bone level changes, patient satisfaction, number of appointments and surgical interventions recorded, when possible, by blinded assessors. RESULTS: Three patients dropped out 1 year after loading from the immediate group vs six from the delayed group. Five implants out of 47 failed in the immediate group (10.6%) vs two out 44 (4.6%) in the delayed group, the difference being not statistically significant (difference in proportion = 6.0%, 95% CI: -8.8% to 20.8%, P = 0.436). In the immediate group 10 patients were affected by 10 complications, while in the delayed group four patients were affected by four complications. The difference was not statistically significant (difference in proportion = 12%, 95% CI: -2% to 26%, P = 0.084). At delivery of the definitive prostheses, 4 months after loading, the mean total PES score was 9.65 ± 1.62 and 10.44 ± 1.47 in the immediate and delayed groups, respectively. At 1 year after loading, the mean total PES score was 9.71 ± 2.71 and 10.86 ± 1.37 in the immediate and delayed groups, respectively. The Total PES score was statistically significantly better at delayed implants both at 4 months (mean difference = 0.79; 95% CI: 0.05 to 1.53; P = 0.03) and at 1 year (mean difference = 1.15; 95% CI: 0.13 to 2.17; P = 0.02). Marginal bone levels at implant insertion (after bone grafting) were 0.04 mm for immediate and 0.11 mm for delayed implants, which was statistically significantly different (mean difference = 0.07; 95% CI: 0.02 to 0.12; P < 0.0001). One year after loading, patients in the immediate group lost on average 1.06 mm and those from the delayed group 0.63 mm, the difference being statistically significant (mean difference = 0.43 mm; 95% CI: 0.15 to 0.61; P < 0.0001). All patients were fully or partially satisfied both for function and aesthetics, and would undergo the same procedure again both at 4 months and 1 year after loading. Patients from the immediate group required on average 7.48 ± 1.45 visits to the clinician and 2.14 ± 0.49 surgical interventions and to have their definitive prostheses delivered vs 10.30 ± 0.99 visits and 3.08 ± 0.40 surgical interventions for the delayed group, the difference being statistically significant (P < 0.001 for visits, and P < 0.001 for surgical interventions). CONCLUSIONS: Preliminary 1 year follow-up data suggest that immediate placement of 6.0 to 8.0 mm wide diameter implants in molar extraction sockets yielded inferior aesthetic outcomes than ridge preservation and delayed placement of conventional 4.0 to 5.0 mm diameter implants.

Studying atmospheric neutrino oscillations in the few-GeV range with a multimegaton detector promises to determine the neutrino mass hierarchy. This is the main science goal pursued by the future KM3NeT/ORCA water Cherenkov detector in the Mediterranean Sea. In this paper, the processes that limit the obtainable resolution in both energy and direction in charged-current neutrino events in the ORCA detector are investigated. These processes include the composition of the hadronic fragmentation products, the subsequent particle propagation and the photon-sampling fraction of the detector. GEANT simulations of neutrino interactions in seawater produced by GENIE are used to study the effects in the 1 - 20 GeV range. It is found that fluctuations in the hadronic cascade in conjunction with the variation of the inelasticity y are most detrimental to the resolutions. The effect of limited photon sampling in the detector is of significantly less importance. These results will therefore also be applicable to similar detectors/media, such as those in ice., 37 pages, 28 figures, JHEP published version

PURPOSE: To compare the efficacy of 1-stage versus 2-stage lateral maxillary sinus lift procedures. MATERIALS AND METHODS: Sixty partially edentulous patients requiring 1 to 3 implants and having 1 to 3 mm of residual bone height and at least 5 mm bone width below the maxillary sinus, as measured on CT scans were selected. They were randomised according to a parallel group study design into two equal arms to receive either a 1-stage lateral window sinus lift with simultaneous implant placement or a 2-stage procedure with implant placement delayed by 4 months, using a bone substitute in three different centres. Implants were submerged for 4 months, loaded with reinforced provisional prostheses, which were replaced, after 4 months, by definitive prostheses. Outcome measures, assessed by masked assessors, were: augmentation procedure failures; prosthesis failures and implant failures; complications; and marginal peri-implant bone level changes. Patients were followed up to 1 year after loading. Only data of implants placed in 1 to 3 mm of bone height were reported. RESULTS: Two patients dropped out from the 1-stage group and none from the 2-stage group. No sinus lift procedure failed in the 1-stage group but one failed in the 2-stage group, the difference being not statistically significant (P = 1.00). Two prostheses failed or could not be placed in the planned time in the 1-stage group and one in the 2-stage group, the difference being not statistically significant (P = 0.51). Three implants failed in three patients of the 1-stage group, versus one implant in the 2-stage group, the difference being not statistically significant (P = 0.28). Two complications occurred in the 1-stage group and one in the 2-stage group, the difference being not statistically significant (P = 0.61). One year after loading, 1-stage treated patients lost an average of -1.01 mm (SD: 0.56) of peri-implant bone and 2-stage sites about -0.93 mm (SD: 0.40). There were no statistically significant differences in bone level change between groups 1 year after loading (-0.08 mm 95%CI: -0.33 to 0.18 P = 0.56). CONCLUSION: No statistically significant differences were observed between implants placed according to 1- or 2-stage sinus lift procedures. However this study may suggest that in patients having residual bone height between 1 to 3 mm below the maxillary sinus, there might be a slightly higher risk for implant failures when performing a 1-stage lateral sinus lift procedure.

PURPOSE: To compare the efficacy of 1-stage versus 2-stage lateral maxillary sinus lift procedures. MATERIALS AND METHODS: Sixty partially edentulous patients requiring 1 to 3 implants and having 1 to 3 mm of residual bone height and at least 5 mm of bone width below the maxillary sinus, as measured on CT scans, were randomised into two equal groups to receive either a 1-stage lateral window sinus lift with simultaneous implant placement or a 2-stage procedure with implant placement delayed by 4 months using a bone substitute in 3 different centres. Implants were submerged for 4 months and loaded with reinforced provisional prostheses, which were replaced, after 4 months, by definitive prostheses. Outcome measures were augmentation procedure failures, prosthesis failures, implant failures, complications and marginal peri-implant bone loss assessed by a blinded outcome assessor. Patients were followed up to 4 months after loading. Only data of implants placed in 1 to 3 mm of bone height were reported. RESULTS: Two patients dropped out from the 1-stage group and none from the 2-stage group. No sinus lift procedure failed in the 1-stage group but 1 failed in the 2-stage group, the difference was not statistically significant (P = 1.00). Two prostheses failed or could not be placed in the planned time in the 1-stage group and 1 in the 2-stage group, the difference was not statistically significant (P = 0.51). Three implants failed in 3 patients of the 1-stage group versus 1 implant in the 2-stage group, the difference was not statistically significant (P = 0.28). Two complications occurred in the 1-stage group and 1 in the 2-stage group, the difference was not statistically significant (P = 0.61). There were no statistically significant differences in bone loss between groups at loading (0.05 mm). Sites treated in 1 stage lost an average of 0.56 mm (SD: 0.36; 95% CI: -0.70 to -0.42; P < 0.001) of peri-implant bone and 2-stage sites approximately 0.61 mm (SD: 0.34; 95% CI: -0.74 to -0.48; P < 0.001). CONCLUSIONS: No statistically significant differences were observed between implants placed according to 1- or 2-stage sinus lift procedures. However, this study may suggest that in patients having a residual bone height between 1 and 3 mm below the maxillary sinus there might be a slightly higher risk for implant failures when performing a 1-stage lateral sinus lift procedure.

To evaluate whether 5 × 5 mm dental implants with a novel nanostructured calciumincorporated titanium surface could be an alternative to implants at least 10 mm long placed in bone augmented with bone substitutes in posterior atrophic jaws.A total of 40 patients with atrophic posterior (premolar and molar areas) mandibles having 5 to 7 mm of bone height above the mandibular canal and 40 patients with atrophic maxillae having 4 to 6 mm below the maxillary sinus, were randomised according to a parallel group design to receive one to three 5 mm implants or one to three at least 10 mm-long implants in augmented bone at two centres. All implants had a diameter of 5 mm. Mandibles were vertically augmented with interpositional bovine bone blocks and resorbable barriers. Implants were placed after 4 months. Maxillary sinuses were augmented with particulated porcine bone via a lateral window covered with resorbable barriers and implants were placed simultaneously. All implants were submerged and loaded after 4 months with provisional prostheses. Four months later, definitive screw-retained or provisionally cemented metal-ceramic or zirconia prostheses were delivered. Patients were followed up to 1 year post-loading and the outcome measures were prosthesis and implant failures, any complications and peri-implant marginal bone level changes.One maxillary grafted patient dropped out before the 1-year evaluation. In mandibles, 1 grafted patient did not want to go ahead with the treatment because of multiple complications and graft failure, and another grafted patient did not receive his prostheses due the loss of 2 implants. In maxillae, one 5 × 5 mm implant failed with its provisional crown 3 months post-loading. There were no statistically significant differences in prostheses and implant failures. Significantly more complications occurred at both mandibular and maxillary grafted sites: 17 augmented patients were affected by complications versus 8 patients treated with short implants in the mandible (P = 0.0079; difference in proportion = -0.45; 95% CI -0.67 to -0.15), and 5 sinus-lift patients versus none treated with maxillary short implants (P = 0.047; difference in proportion = -0.25; 95% CI -0.44 to -0.06). Patients with mandibular short implants lost on average 0.94 mm of peri-implant bone at 1 year and patients with 10 mm or longer mandibular implants lost 1.03 mm. Patients with maxillary short implants lost on average 0.87 mm of peri-implant bone at 1 year and patients with 10 mm or longer maxillary implants lost 1.15 mm. There were no statistically significant differences in bone level changes up to 1 year between short and longer implants in maxillae (mean difference -0.28 mm, 95% CI -0.56 to 0.01, P = 0.051) and in mandibles (mean difference -0.09 mm, 95% CI -0.26 to 0.08, P = 0.295).One year after loading, 5 × 5 mm implants achieved similar results compared to longer implants placed in augmented bone. Short implants might be a preferable choice to bone augmentation especially in posterior mandibles since the treatment is faster, cheaper and associated with less morbidity, however 5 to 10 years of post-loading data are necessary before making reliable recommendations.MegaGen partially supported this trial and donated implants and prosthetic components used in this study, whereas Tecnoss donated the biomaterials. The data belonged to the authors and by no means did the manufacturers interfere with the conduct of the trial or the publication of its results.

PURPOSE: To evaluate whether 5 × 5 mm dental implants with a novel nanostructured calcium-incorporated titanium surface could be an alternative to at least 5 × 10 mm-long implants placed in bone augmented with bone substitutes in posterior atrophic jaws. MATERIALS AND METHODS: Forty patients with atrophic posterior (premolar and molar areas) mandibles having 5 to 7 mm of bone height above the mandibular canal and 40 patients with atrophic maxillae having 4 to 6 mm below the maxillary sinus, were randomised according to a parallel group design to receive one to three 5 × 5 mm implants or one to three at least 5 × 10 mm-long implants in augmented bone at two centres. Mandibles were vertically augmented with interpositional bovine bone blocks and resorbable barriers and implants were placed after 4 months. Maxillary sinuses were augmented with particulated porcine bone via a lateral window covered with resorbable barriers and implants were placed simultaneously. All implants were submerged and loaded after 4 months with provisional prostheses. Four months later, definitive screw-retained or provisionally cemented metal-ceramic or zirconia prostheses were delivered. Outcome measures were prosthesis and implant failures as well as any complication. RESULTS: Patients were followed to 4 months post-loading with the exception of one patient who underwent mandibular augmentation and had multiple complications at and after grafting, and subsequent graft failure, who did not want to go ahead with the treatment. This case was considered a complete failure. There were no statistically significant differences in prosthesis and implant failures. In mandibles, apart from the complete graft failure, one 5 × 10 mm implant failed at placement of the provisional prosthesis. In maxillae, one 5 × 5 mm implant failed with its provisional crown 3 months after loading. All complications occurred before loading. Significantly more intra- and postoperative complications occurred at both mandibular and maxillary grafted sites: 16 augmented patients were affected by complications versus 8 patients treated with short implants in the mandible (P = 0.022; difference in proportion = 0.40; CI 95% 0.12 to 0.68), and 5 sinus-lifted patients versus none treated with maxillary short implants (P = 0.047; difference in proportion = 0.25; CI 95% 0.06 to 0.44). CONCLUSIONS: Short-term data (4 months after loading) indicate that 5 × 5 mm implants achieved similar results compared to longer implants placed in augmented bone. Short implants might be a preferable choice to bone augmentation especially in posterior mandibles since the treatment is faster, cheaper and associated with less morbidity. However, 5 to 10 years of post-loading data are necessary before making reliable recommendations

PURPOSE: To compare the efficacy of two different techniques for maintaining the space beneath a maxillary lining lifted using a lateral window approach: rigid synthetic resorbable barriers versus granular anorganic bovine bone. MATERIALS AND METHODS: Ten partially edentulous patients having bilaterally 1 to 5 mm of residual bone height and at least 5 mm bone width below the maxillary sinuses, were randomised in a split-mouth study design, to receive a rigid Inion GTR Biodegradable Membrane System barrier without any graft on one side and 100% loosely packed granular Bio-Oss on the contralateral side following a lateral window, two-stage, sinus lift procedure. After 6 months, two or three implants were inserted at each side and submerged for 4 months. Implants were loaded with provisional acrylic prostheses and replaced, after 4 months, by definitive metal-ceramic prostheses cemented with provisional cement. Outcome measures were implant and prosthetic failures, any complication and peri-implant marginal bone level changes assessed by a blinded outcome assessor. All patients were followed up to 1 year after loading. RESULTS: One patient dropped out after implant placement. One distal implant failed at the Inion side just before delivery of the definitive prosthesis, which was cut and maintained as a single crown. Four complications occurred in three patients at Inion sites (two sinus lining perforations, one fracture of the ceramic cusp of the definitive prosthesis, one iatrogenic peri-implantitis) versus two complications at Bio-Oss sites (one sinus lining perforation and one iatrogenic peri-implantitis). There were no differences for failures or complications between groups; however, in one of the patients where a perforation occurred at the Inion site, at implant placement, the sinus was filled two-thirds with soft tissue and the site was retreated with Bio-Oss. There were no statistically significant differences in bone loss between groups. One year after loading, Inion sides lost an average of 1.5 mm of periimplant bone and Bio-Oss sides about 1.7 mm. CONCLUSIONS: A bone graft may not be needed to augment atrophic maxillary sinuses since it is sufficient to keep space with a rigid barrier; however, it may be simpler to fill sinuses with a bone substitute than positioning a rigid barrier to maintain space.

Scopo di questo studio retrospettivo multicentrico è stato quello di valutare l'utilità e l'efficacia clinica degli impianti Rescue. Sono stati inseriti dal febbraio all'aprile 2008 48 impianti su 48 pazienti: 22 nel mascellare superiore e 26 nella mandibola. La percentuale di sopravvivenza implantare a 24 mesi dal carico funzionale è stata pari al 95.8%. L'entità del riassorbimento a 12 e 24 mesi dal carico protesico è stata rispettivamente 0.56 mm(0.10-1.88) e 1.28 mm (0.41-2.39). Il riassorbimento osseo non è risultato essere correlato al tipo di setto interradicolare residuo. Sulla base dei risultati ottenuti, si può ipotizzare che l'impianto di diametro largo rappresenti una valida alternativa all'impianto differito ed alla chirurgia rigenerativa in siti postestrattivi gravemente compromessi, anche se necessitano altri studi clinici prospettici randomizzati e controllati per validare questi risultati.

To compare the efficacy of two different techniques to augment maxillary sinuses using a lateral window approach: rigid synthetic resorbable barriers (Inion) versus granular anorganic bovine bone (Bio-Oss). MATERIALS AND METHODS: Ten partially edentulous patients having bilaterally 1 to 5 mm of residual bone height and at least 5 mm bone width below the maxillary sinuses, as measured on computed tomography (CT) scans, were randomised to receive two different 2-stage sinus lift procedures using the lateral window approach. In one side, the sinus lining was raised by placing a resorbable rigid Inion barrier without any bone substitute whereas the contralateral side was loosely packed with 100% granular Bio-Oss. After 6 months, 2 to 3 implants were inserted at each side and submerged for 4 months. Implants were loaded with provisional acrylic prostheses and replaced after 4 months, by definitive screwretained metal-ceramic prostheses. Outcome measures were: time necessary to complete the augmentation procedure, bone gain on CT scans, histomorphometry, any complication, implant and prosthetic failures, and clinician and patient preference assessed by a blinded outcome assessor. All patients were followed up to 5 months after loading. RESULTS: No patient dropped out. There was no significant difference in time to complete the augmentation procedure (19.8 minutes for Inion versus 20.5 for Bio-Oss). After 6 months, both interventions gained bone in a highly statistically significant way (14.4 mm for Inion versus 14.1 mm for Bio- Oss) with no significant differences between the procedures. Histologically, more new bone formed at Bio-Oss treated sites (36.1% versus 24.2%), the difference being highly statistically significant (P = 0.002). There were no differences in complications between groups (2 perforations of the maxillary lining at Inion treated sites versus 1 at a Bio-Oss site), however, in one of the patients where a perforation occurred at the Inion site, at implant placement, the sinus was two-thirds filled with soft tissue and the site was successfully retreated with Bio-Oss. No implant failed. The clinician preferred Bio-Oss because it was simpler to handle. There were no statistically significant differences in patient preference 1 month after surgery and 1 month after delivery of definitive prostheses: 8 patients had no preference while 2 preferred the Bio-Oss treated side. CONCLUSIONS: Although bone grafting is not needed to augment atrophic maxillary sinuses since it is sufficient to keep space with a rigid barrier, bone was histologically more mature and appeared to be clinically harder when using Bio-Oss. Moreover, it was judged simpler to fill sinuses with a bone substitute than to position a rigid barrier for maintaining space.

A simple model is proposed, at the macrolevel of variable aggregation, as a support for policy making in the control of goods transportation growth by possible alternative modes. The impact of feasible changes in the levying of "carbon tax" can be investigated with the proposed model, as well as the effects of investments in infrastructure and of the coverage of operational costs. Based on some transport externalities, various cost indices are identified and suitably minimized using optimization techniques, so that a quantitative definition of public policies can be derived. As an example, the model is used to evaluate an application of alternative policies in Germany. This case study shows that the model system of goods transportation has a slight sensitivity to the public interventions considered. The application of the carbon tax shows significant effects on the increase of fiscal revenues rather than on the reduction of carbon dioxide emissions and on the share of road transportation. Reductions in carbon dioxide emissions and in transportation by road are best achieved by higher investment in the infrastructures of alternative modes of transport, together with a reduction in fuel taxation.

The reversible nature of the direct esterification of acids with alcohols limits the use of this process in the biocatalitic kinetic resolution of chiral acids. A new irreversible procedure, using orthoesters, have been developed.