Extraoral vertical ramus osteotomy (EVRO) is used in orthognathic surgery for the treatment of mandibular deformities. Originally, EVRO required postoperative intermaxillary fixation (IMF). EVRO has ...been developed using rigid fixation, omitting postoperative IMF. We examined retrospectively the long-term stability and postoperative complications for patients with mandibular deformities who underwent EVRO with internal rigid fixation. Patients who were treated with EVRO for a mandibular deformity in the period 2008–2017 at the Clinic of Oral and Maxillofacial Surgery, Mölndal, Sweden were included (N = 26). Overjet and overbite were calculated digitally and cephalometric analyses were performed preoperatively, and at three days, six months, and 18 months postoperatively. There was a general setback of the mandible, decreased gonial angle and reduced degree of skeletal opening. Excellent dental and vertical skeletal stabilities were seen up to 18 months postoperatively, although relapse was seen sagitally up to six months postoperatively. Since the overjet did not show any significant change over time, the sagittal skeletal changes have been attributed to dental compensation. There was no permanent damage to the facial nerve and 5.8% neurosensory damage to the inferior alveolar nerve was observed.
We quantified the horizontal distribution of Late Cretaceous (late Maastrichtian) benthic foraminifera for 10 upper bathyal to abyssal localities, that cover a wide range of environmental settings ...throughout the Tethyan realm. For the first time, a quantitative faunal study is performed in order to identify and explain the differences between Late Cretaceous benthic foraminiferal faunas from the deep open ocean and from the shallower marginal seas of the Tethys. The results from correspondence analysis indicate that the main arrangement of the various sites coincides with a paleobathymetric ranking, which we consider to be primarily a reflection of gradients in trophic resources and oxygen levels. Five benthic foraminiferal assemblages were found to characterize bathymetrically and latitudinally different environmental settings within the Tethyan realm: (1) a Marginal Tethyan Assemblage (e.g., large Cibicidoides spp. and Sliteria varsoviensis) characteristic of the relatively highly fertile environment of the southern Central Tethyan margin, (2) an Abyssal Tethyan Assemblage (e.g., Aragonia spp. and Nuttallides truempyi) that signifies the more oligotrophic deep open-ocean conditions in the Western Tethys, (3) a Northwestern Tethyan Assemblage containing some high latitude ("boreal") faunal elements (e.g., Gavelinella pertusa and Stensioeina pommerana) characteristic of the northernmost part of the Western Tethys, (4) a Shallow Bathyal Assemblage (e.g., Bolivinoides draco and Eouvigerina subsculptura), which is composed of more or less ubiquitous taxa, and finally, (5) a Deep Bathyal Assemblage (e.g., Bulimina trinitatensis and Gavelinella beccariiformis), which also has a mostly ubiquitous distribution except for the shallow sites of the southern margin of the Central Tethys, where it is virtually absent. Morphotype analysis of the total fauna reveals distinct differences in proportions of endobenthic and epibenthic morphologies between the various sites, but a clear trend between the deep open ocean and the marginal seas cannot readily be discerned. However, a comparison of the proportions of morphotypes within the five assemblages resulting from correspondence analysis signifies clear trends between the various environmental settings. This enables us to distinguish various trophic regimes within the Tethyan realm; yet, we found no faunal indications of either true oligotrophic or eutrophic settings. We conclude that large areas of the latest Cretaceous bathyal environment of the Tethys were more or less mesotrophic in character, but nevertheless, abundance-patterns of morphogroups within each of the five assemblages were found to reflect depth-related gradients, which in turn are influenced by variations in food availability and oxygen concentration at the seafloor.
To evaluate the human bone tissue response to 2 surfaces (oxidized or turned) on commercially available titanium implants.
Screw-type turned (control) and oxidized (test) micro-implants were ...manufactured in the same manner as commercially available turned and oxidized (TiUnite, Brånemark System) implants. The thickness of the oxide layer of the test implants was on average 10 microm, corresponding to the oxide thickness of the apical part of the TiUnite implant. Twenty patients received 1 test and 1 control micro-implant each during implant surgery. Before placement, the surface topography of the implants was characterized with an optical confocal laser profilometer. After a mean healing period of 6.6 months in the maxilla and 3.5 months in the mandible, the micro-implants and surrounding tissue were removed with a trephine bur. Histologic sections were produced, and the specimens were analyzed histomorphometrically.
Surface roughness and enlargement were greater for the oxidized implants than for the turned implants. All micro-implants, except for 2 controls, were found to be clinically stable at the time of retrieval. Histomorphometric evaluation demonstrated significantly higher bone-to-implant contact for the oxidized implants, whether placed in the maxilla or in the mandible. Significantly more bone was found inside the threaded area for the oxidized implants placed in the mandible and maxilla, but there was no difference between implants with regard to position (maxilla or mandible).
The stronger bone response to the oxidized implants may have contributed to the fact that 2 control implants but no test implants were lost. The reason for these findings may depend on one or multiple differences of the surfaces between test and control implants: (1) the thicker oxide layer itself, (2) increased surface roughness, (3) different surface morphology in terms of porosity, or (4) change in crystal structure.
The present histologic study in human jawbone demonstrated a significantly higher bone response for anodic oxidized titanium implants than for implants with a turned surface.
: Twenty‐seven patients received 2 microimplants each during implant surgery. One microimplant was blasted with 25 μm sized particles of TiO2; the other was left as machined i.e. a turned surface. ...Before insertion the surface topography was characterized with an optical confocal laser profilometer. The surface roughness was greater than standard implants, and was similar for both surface modifications averaging over all parts of the implant i.e. tops, valley and flanks. The mean surface roughness from flank measurements only replicated previously reported findings: i.e. significantly rougher surfaces on blasted implants. After a mean healing period of 6.3 months in the maxillae and 3.9 months in the mandible, the microimplants and surrounding tissue were removed with a trephine burr. The histomorphometrical evaluation demonstrated significantly higher bone‐to‐implant contact for the blasted implants, inserted in the maxilla or in the mandible. Significantly more bone was found inside the threaded area for the blasted implants in the mandible, but there was no difference for implants positioned in maxillae.
Résumé
Vingt‐sept patients ont reçu deux micro‐implants durant une chirurgie implantaire. Un des ces micro‐implants était soufflé avec des particules de titane (TiO2) de 25 μm; l’autre était laissé usiné. Avant l’insertion, la tophographie de surface était caractérisée par un profilomètre de laser optique confocal. La rugosité de surface était supérieure aux implants standards et était semblable pour les deux modifications de surface ainsi que pour toutes les parties de l’implant c.‐à‐d. les sommets, les étranglements et les flancs. La rugosité moyenne de surface des mesures sur les flancs était semblable à ce qui avait été rapporté précédemment c.‐à‐d. surface plus rugueuse sur les implants soufflés. Après une période de guérison moyenne de 6,3 mois au niveau maxillaire et de 3,9 mois au niveau mandibulaire, les micro‐implants et les tissus avoisinants ont été enlevés par un trépan. L’évaluation histomorphométrique a démontré significativement plus de contact os‐implant pour les implants soufflés, qu’ils aient été insérés dans le maxillaire ou dans la mandibule. Une quantité significativement supérieure d’os a été trouvée à l’intérieur des aires avec filetage des implants soufflés dans la mandibule, mais aucune différence pour ceux placés dans le maxillaire.
Zusammenfassung
Siebenundzwanzig Patienten erhielten während der Implantatchirurgie je 2 Mikro‐Implantate. Eines der Mikro‐Implantate war mit 25 μm grossen Partikeln aus TiO2 sandgestrahlt; das andere wurde maschinell bearbeitet belassen, was einer gedrehten Oberfläche entsprach. Vor dem Einsetzen wurde die Topographie der Oberfläche mit einem optischen confokalen Laserprofilometer bestimmt. Die Rauhigkeit der Oberfläche war grösser als bei Standardimplantaten und war für beide Oberflächenmodifikationen ähnlich, wenn der Mittelwert über alle Regionen der Implantate, d.h. Spitzen, Täler und Abhänge betrachtet wurde. Die Messungen der mittleren Rauhigkeit der Oberflächen im Bereich der Abhänge bestätigte bereits früher veröffentlichte Resultate, nämlich signifikant rauhere Oberflächen bei sandgestrahlten Implantaten. Nach einer mittleren Einheilungszeit von 6.3 Montaten im Oberkiefer und 3.9 Monaten im Unterkiefer wurden die Mikro‐Implantate und die umgebenden Gewebe mit einer Hohlfräse entfernt. Die histomorphometrische Auswertung zeigte signifikant mehr Knochen‐Implantat‐Kontakt für die sandgestrahlten Implantate, sowohl im Ober‐ als auch im Unterkiefer. Innerhalb der Gewindegänge von sandgestrahlten Implantaten aus dem Unterkiefer konnte signifikant mehr Knochen gefunden werden als bei den maschinell berarbeiteten. Aber bei den Implantaten, welche im Oberkiefer plaziert wurden, bestanden keine solchen Unterschiede.
Resumen
Veintisiete pacientes recibieron 2 microimplantes cada uno durante cirugía de implantes. Un microimplante fue pulverizado con particulas de TiO2 de 25 μm de tamaño; el otro se dejó pulido i.e. superficie torneada. Antes de la inserción la superficie topográfica de caracterizó con un profilómetro láser óptico confocal. La rugosidad de la superficie fue mayor que en implantes estándar, y fue similar para las dos modificación de superficie de media sobre todas las partes del implante i.e. altos, valles y flancos. La rugosidad media de las mediciones del flanco sólo replicaron los hallazgos previamente reportados: i.e. superficies significativamente más rugosas en implantes pulverizados. Después de un periodo de cicatrización medio de 6,3 meses en el maxilar y 3.9 meses en la mandíbula, los microimplantes y el tejido circundante se retiraron con una fresa de trépano. La evaluación histomorfométrica demostró un contacto hueso‐implante significativamente mas alto para los implantes pulverizados, insertados en el maxilar o en la mandíbula. Se encontró significativamente mas hueso en el área roscada de los implantes pulverizados en la mandíbula, pero no hubo diferencias para los implantes colocados en el maxilar.
A survey of 60 rural, 62 urban Alaska women (64% Alaska Native) indicated positive dietary and lifestyle habits. Diets were characterized by boiled meats, high intakes of omega-3 fish, sea mammals ...and few desserts. Food insecurity reported by 39% rural and 7% of urban. Hunger was reported by 16% of rural and 5% of urban women. Traditional activities were walking, harvesting fish and picking berries. One third of calories came from non-traditional sugared and fruit juice beverages. Few respondents reported chronic diseases. Nutrition and health educational interventions in Alaska Native communities should reinforce existing positive lifestyle habits, involve Elders and tribal leaders, and incorporate Native values, customs and traditions.
ABSTRACT
Background: Regarding the Brånemark implant system, nonresorbable sutures have been advocated for reapproxima‐tion of the flaps. Fast‐absorbable sutures are frequently used in oral surgery, ...which is convenient for both the patient and the surgeon. It would be advantageous if fast‐absorbable sutures are suitable in implant surgery as well.
Purpose: The purpose of this study was to compare irradiated polyglactin 910 (Vicryl Rapide, Ethicon GmbH, Norderstedt, Germany) suture with a nonresorbable polyfilament suture (Supramid, Schwarz, Resorba GmbH, Nürnberg, Germany) used in oral implant surgery.
Materials and Methods: The study comprised 101 edentulous patients (52 females, 49 males) who were provided with 350 Brånemark implants. They were randomized to receive either Vicryl Rapide suture (n = 61) or 3‐0 Supramid suture (n = 40). The patients were evaluated after 10 days and at the time of abutment surgery. Any wound complications and implant losses were recorded.
Results: The implant failure rate at abutment surgery was low (1.2%), and no difference was seen between the two suture groups. A higher incidence of complications (mainly wound dehiscence) was found in the absorbable suture group, especially when a continuous suture was used.
Conclusions: The results of this study indicate that it is possible to use irradiated polyglactin 910 sutures in oral implant surgery without affecting the rate of early implant failure. However, it is recommended to add interrupted “security sutures” if a continuous suture technique is used in combination with fast‐absorption suture material.
The aim of this thesis was to evaluate the indications for and the results of temporomandibular joint (TMJ) surgery in patients with long-standing severe orofacial pain and dysfunction as well as in ...patients with fractures of the condylar neck. The patients with long-standing pain and dysfunction had had symptoms for a mean time of 4 years, had been treated conservatively for a mean time of 2.5 years, and had undergone numerous conservative treatment methods without improvement except for a minor increase in mouth opening capacity. The indications for surgery were strict; only 1% or less of all the patients referred to the departments with a diagnosis of temporomandibular disorder (TMD) were prescribed surgery, which was considered to be the only remaining option. The TMJ surgery reduced pain, sleeping problems, and analgesic consumption and improved mouth opening capacity. The procedure showed low morbidity except for a facial nerve disturbance in three patients. Postoperatively, the bite force was observed to be normalised, and the radiographic examination showed moderate to severe osteoarthrotic changes. These changes, though extensive, were considered to be the normal outcome of diskectomy and without clinical significance, even though they resembled degenerative joint disease. In study V, surgery was performed on patients with a clear diagnosis of anterior disk displacement (ADD) with or without reduction. The preoperative pain and mouth opening capacity were markedly improved as well as other subjective symptoms. Although surgical morbidity was low, some radiographic changes were clearly detectable. In agreement with earlier reports, patients with a distinct diagnosis of ADD with or without reduction were clearly helped by diskectomy. In cases of ADD with or without reduction, it can be concluded that unsuccessful conservative treatment should not exceed 3-6 months but be discontinued in favour of the documented advantages of surgery in these cases. Patients with ankylosis should be treated surgically without delay. Unclear diagnoses such as arthralgia and osteoarthrosis with symptoms should be excluded from surgery unless overlapping muscular hyperactivity has been excluded as a major cause of the patients problem. Diskectomy is a useful surgical procedure for patients with severe long-standing TMD. It was shown in study VI that patients with dislocated fractures of the condylar neck can be successfully treated with open surgical reduction when the dislocation is large and associated with symptoms and limited function. When cognitive-behavioural profiles were measured psychometrically in study VII, a dysfunctional profile was more common in patients with myofascial pain and pain with an obscure origin than in other patients diagnosed with TMD. The dysfunctional profile was also common in patients in whom treatment of a conservative or surgical nature had failed. Among TMD patients with disk displacement, adaptive copers were most common in successfully diskectomized patients and least common in patients about to undergo invasive treatment.
To evaluate treatment outcome with Zygoma fixtures (Nobel Biocare, Göteborg, Sweden) with regard to fixture survival, patient satisfaction, and function of prosthesis replacement.
The treatment ...outcome of 76 patients treated with 145 Zygoma fixtures at 16 centers was evaluated. Patient’s and dentist’s evaluations of the functional and aesthetic outcome of the treatment were assessed at delivery of prosthesis and at the 1-year follow-up visit. At the 1-year follow-up visit, the status of the peri-implant mucosa around the abutments and the amount of plaque were registered.
Sixty-six of the 76 patients, with 124 Zygoma fixtures supporting the prosthetic restorations, were evaluated at the 1-year follow-up. The overall survival rate for the Zygoma fixtures was 97.9% after 1-year of follow-up. Eighty percent of the patients were fully satisfied with both aesthetic and functional outcome at the time of prosthetic insertion and at the 1-year follow-up. All reported data from the dentists, with the exception of one restoration with several abutment screw loosenings, scored from acceptable to excellent for the aesthetic and functional outcome of the treatment. The status of peri-implant mucosa was recorded as normal in approximately 60% of the sites. Plaque, when present, was more often detected on the palatal surfaces compared with the buccal surfaces.
This 1-year follow-up of Zygoma fixtures has shown good results with an acceptable number of minor complications and a majority of satisfied patients.
Forty three patients with severely resorbed maxillae who had been referred for implant treatment were assigned to 1 of 3 treatment options: bone grafting and implant placement (graft group), modified ...implant placement with no bone grafting (trial group), or optimized complete dentures (no-implant group). Sixteen, 20, and 7 patients, respectively, were assigned to the 3 groups. The patients have been examined annually, and at the time of this report they had been followed for 3 to 5 years after treatment. At the 1-year follow-up, 10% (22 of 221) of the implants had been lost, and at the 2-year follow-up, 18% of the implants had been lost (40 of 221; 25% in the graft and 13% in the trial group); after that time, no further losses occurred. Life table analysis showed cumulative success rates of 82% in the graft group and 96% in the trial group after 1 year, and 74% and 87%, respectively, at the final examination after 3 to 5 years. The failure rate was higher in smokers than in non-smokers. A substantial reduction of the grafted bone, especially of onlay grafts, occurred early after grafting surgery in many patients. Mean marginal peri-implant bone loss was 0.6 mm during the period from prosthesis connection to the 1-year follow-up, and from the 1-year to the 3-year follow-up, average peri-implant bone loss was 0.3 mm in the graft group and 0.5 mm in the trial group. The results corroborated previous findings that patients with severely resorbed maxillae have an increased risk of implant failure in comparison to patients with good bone quantity and quality. However, in this investigation, practically all implant losses occurred during the first 2 years, whereupon a steady state seemed to follow for up to 5 years after loading.
Clinical and radiographic examination was used to select patients with a suspected need of guided tissue regeneration (GTR). Fifteen patients with 20 fixtures were included in the study. Nine (45%) ...of the fixtures were completely covered with bone at fixture surgery and no GTR was required in these cases. On the remaining 11 fixtures, one or more sites were exposed and thus an expanded polytetrafluoroethylene membrane was used. The regenerative results were assessed using 2 methods, a) calculation of exposed threads in the mouth and on projected colour slides, b) photometric evaluation of exposed area. In total, the membrane group showed a bone gain of 81% when threads were calculated. Almost complete agreement in percentage of bone gain was observed between buccal (80.7%) and lingual (82.6%) sites. Photometric evaluation for the buccal sites showed a bone gain of 74%. Complete bone regeneration (100%) was achieved when healing was free from complications and also under an exposed membrane when infection was absent. The results indicate that the membrane technique is highly successful for treatment of exposed implants when healing is free from complications. It also shows that clinical and radiographic examination is not precise enough to differentiate between those patients planned for routine fixture surgery and those with a supplementary need for GTR. Thus access to GTR technique is important when treatment is planned for borderline cases.
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