Long-term survival analysis of dental implants & implant-supported prostheses in patients after squamous cell carcinoma in head and neck region

Purpose: The prosthetic rehabilitation of head and neck cancer patients following ablative surgery and possible radiochemotherapy can be extremely challenging for the surgeons and prosthetists. A conventional prosthetic solution is often not feasible due to the alteration of anatomical conditions following surgical rehabilitation. In such cases, implant-retained prostheses are often the only option for the successful rehabilitation of patients in the long-term. In this study, the long-term clinical success of dental implants and implant-supported prostheses in patients following surgical resection are evaluated and analyzed. Additionally, potential influencing factors were evaluated. Material and Methods: In this study, 60 patients (20 women, 40 men) with the mean age of 62.75 years (41-88 years) were included. Prior to implant placement, 35 patients also received radiotherapy and cisplatin-based chemotherapy postoperatively. Overall, 330 implants were inserted in these patients. The mean observation period was 86 months (4-272 months). The patients were examined every 6 months at the first 3 years and then every 12 months according to a standard protocol and complications were documented. In the clinical examinations, the implant success was regularly assessed according to the criteria of Buser. Kaplan-Meier Curve was used for the evaluation of implant survival and the Log Rank test for overall differences according to gender, radiotherapy, localization (maxilla/mandible) and vestibuloplasty. Results: Of the 330 implants examined, 122 were placed in the maxilla and 208 in the mandible. Overall, 212 implants were placed in 35 irradiated patients. A total of 27 implants were lost during the observation period. The cumulative survival rate was 99.7% after 3 years, 92.7% after 7 years and 88.3% after 10 years. Gender and radiotherapy did not have a significant influence of the survival of dental implants in oral cancer patients. However, age, localization of the implants (maxilla/mandible) and a vestibuloplasty according to Heberer and Nelson as soft tissue management showed a significant difference. Discussion: This study reveals a high and steady cumulative survival rate of dental implants after 10 years following ablative surgery in non-irradiated and irradiated head and neck cancer patients. The requirements for long-term success are: optimal soft tissue management, recall system and excluding irradiated patients with a smoking habit from the study.Zielstellung: Die prothetische Rehabilitation von Patienten mit Tumoren im Kopf- Halsbereich nach erfolgter chirurgischer Behandlung und etwaiger Radiochemotherapie stellt eine große Herausforderung für die Chirurgen und Prothetiker dar. Eine konventionelle prothetische Lösung ist oftmals aufgrund der therapiebedingten Veränderungen der anatomischen Verhältnisse durch Defektrekonstruktionen nicht durchführbar. Die Verankerung des Zahnersatzes mit dentalen Implantaten stellt in solchen Fällen meist die einzige Möglichkeit dar, die Patienten langfristig suffizient zu rehabilitieren. In der vorliegenden Studie wird der klinischer Langzeiterfolg dentaler Implantate und implantat-prothetischer Versorgungen von Patienten nach Tumorresektionen untersucht und ausgewertet. Zusätzlich sollen mögliche Einflussfaktoren evaluiert werden. Material und Methoden: In die vorliegende Studie wurden 60 Patienten (20 Frauen, 40 Männer) mit einem Durchschnittsalter von 62.75 Jahren (41 - 88 Jahre) involviert. Prä implantationem wurden 35 Patienten zusätzlich bestrahlt und erhielten eine cisplatinbasierte Chemotherapie. Insgesamt wurden bei diesen Patienten 330 Implantate inseriert. Der Nachuntersuchungszeitraum betrug durchschnittlich 86 Monate (4 – 272 Monate). Die Patienten wurden anhand eines Standardprotokolls klinisch alle 6 Monate in den ersten 3 Jahren und dann alle 12 Monaten nachuntersucht und die Komplikationen wurden dokumentiert. Bei den klinischen Untersuchungen wurde der Implantaterfolg entsprechend den Erfolgskriterien nach Buser bewertet. Die Kaplan-Meier-Kurve wurde für die Auswertung der Überlebensrate dentaler Implantate und Log Rank Test für den Gesamtvergleich nach Geschlecht, Radiotherapie, Lokalisation (Oberkiefer/Unterkiefer) und Vestibulumplastik benutzt. Ergebnisse: Insgesamt wurden 330 Implantate untersucht, 122 Implantate wurden in den Oberkiefer und 208 Implantate in den Unterkiefer eingesetzt. 212 Implantate wurden bei 35 bestrahlten Patienten inseriert. 27 Implantate gingen innerhalb des Nachuntersuchungszeitraumes zu Verlust. Die kumulative Überlebensrate lag nach 3 Jahren bei 99.7%, nach 7 Jahren bei 92.7% und nach 10 Jahren bei 88.3%. Das Geschlecht und die Radiotherapie hatten keinen Einfluss auf den Langzeiterfolg der Implantate bei Tumorpatienten. Jedoch hatten das Alter, die Lokalisation (Oberkiefer/Unterkiefer) und eine Vestibulumplastik nach Heberer und Nelson als Weichgewebsmanagement einen Einfluss auf den Langzeiterfolg gezeigt. Diskussion: Die Studie zeigt guten klinischen Langzeiterfolg dentaler Implantate nach 10 Jahren bei bestrahlten Patienten und nicht bestrahlten Patienten nach Tumortherapie im Kopf-Hals-Bereich. Die Voraussetzung für den Langzeiterfolg ist optimales Weichgewebsmanagement, ein engmaschigem Recallsystem und das Ausschlusskriterium Nikotinabusus bei bestrahlten Patienten

Učinci carskog reza na peroksidaciju lipida i neke antioksidanse u krvi netom oteljene teladi.

The mode of delivery may have a considerable effect on the state and health of the newborn. Therefore, the purpose of this study was to investigate the effect of a Caesarean section on oxidant and antioxidant status in newborn calves. This study included the neonates of 8 normally calved cows and 8 cows who had undergone by Caesarean section. Malondialdehyde concentrations were significantly higher in the calves delivered by caesarean section compared to the calves of normally calved cows, but catalase activity was significantly lower (P<0.01). Glutathione concentrations tended to increase in the calves delivered by Caesarean section compared to the calves of normally calved cows. There were no significant differences in the glutathione peroxidase activity between the groups. Our results suggest that the malondialdehyde concentrations and catalase activities, which show lipid peroxidation and antioxidant status in newborn calves, change due to Caesarean section. In conclusion, newborn calves are exposed to higher oxidative stress in Caesarean section.Način porođaja može znatno utjecati na stanje i zdravlje novorođenčeta. Stoga je svrha ovoga rada istražiti učinak carskoga reza na oksidacijsko i antioksidacijsko stanje u netom oteljene teladi. Istraživanje je provedeno na osam normalno oteljene teladi i na osam teladi oteljene carskim rezom. Koncentracije malondialdehida bile su značajno veće u teladi oteljene carskim rezom nego li u prirodne oteljene teladi, ali je aktivnost katalaze bila značajno slabija (P<0,01). Koncentracije glutationa bile su povećane u teladi oteljene carskim rezom u odnosu na prirodno oteljenu telad. Nisu bile ustanovljene značajne razlike u aktivnosti glutation peroksidaze među dvjema skupinama. Rezultati upućuju na zaključak da su koncentracije malondialdehida i aktivnost katalaze kao pokazatelji lipidne peroksidacije i antioksidacijskog stanja u novorođene teladi bile promijenjene zbog carskog reza. To govori da je netom oteljena telad zbog carskog reza izložena jačem oksidacijskom stresu

Effects of Exogenous Oxytocin on Embryonic Survival in Cows

The aim of this study was to evaluate the effect of oxytocin on embryonic survival in dairy cows. Pregnancy was verified using the early pregnancy factor (EPF) activity on Day 4 after artificial insemination (AI). Pregnant cows were randomly allotted to two groups: treated (n = 8) and control (n = 8). Oxytocin (100 IU, 5 ml, DIF Turkey) was administered twice daily by intravenous injections to treated cows and sterile saline (5 ml) to control cows immediately before milking on days 4 to 7 after AI. Blood samples were taken via jugular vein every day from day 4 to 8 and every other day until Day 20 following insemination to evaluate the effect of oxytocin on embryonic survival. The embryonic loss was diagnosed in 3 of the 8 cows treated with oxytocin, and embryonic survival rate was 62.5% in this group versus 87.5% in controls. Short cycles occurred in 37.5% of oxytocin-treated cows. At the same time their serum progesterone concentrations rose more slowly than in controls. It was concluded that cows administered oxytocin on days 4 to 7 after insemination are at a higher risk of pregnancy loss

Influence of propylene glycol on conception rate in cows

The aim of the study was to evaluate effect of propylene glycol (PG) drenched during the first 7 days after fixed-time artificial insemination (FTAI) on plasma progesterone (P4) and insulin levels, and on pregnancy rate in Holstein cows in summer. Ovsynch program was performed in 40 healthy Holstein cows. Cows were distributed randomly into two groups as propylene glycol (group PG) (20) and control group (group C) (20). Group PG and group C were daily administered with 500 ml of PG and water , respectively for 7 days from day 0 to 7 post insemination. Pregnancy diagnosis was carried out 60 days after insemination via rectal examination. Cows exposed to moderate heat stress due to temperature-humidity index (74.4 ± 1.9 mean THI). Conception rate for cows in group PG increased 2.9 fold when was compared with group C. On day 7, the insulin levels were higher in group PG than group C. It was concluded that PG administered once daily from day 0 to 7 after FTAI increased insulin and P4 concentrations and the conception rate in Holstein cows. The rise in insulin and P4 levels depending on the drenched PC are likely related with the increases of conception rate

Photoperiod effects on carcass traits, meat quality, and stress response in heart and lung of broilers

This study evaluated effects of photoperiod treatments on slaughter and carcass traits, meat quality, indicators of oxidative stress, and heat shock protein 70 (Hsp70) levels of lung and heart tissues in broilers. Five hundred Ross 308 broiler chicks were used. The treatments consisted of 23 hours of continuous light and one hour of darkness (23L1D), four hours of light followed by two hours of darkness (4L2D), eight hours of light and four hours of darkness (8L4D), and 16 hours of light and eight hours of darkness (16L8D). After 42 days, two birds from each replicate were slaughtered. Birds that had been subjected to 16L8D had lower slaughter, carcass, and breast weights than the other treatments. Significant correlations were observed for slaughter, carcass and breast weights and white stripe. At 10 min post mortem, the pH of the breast was the highest in 23L1D. Breasts from birds subjected to 23L1D and 16L8D had most fat and least protein, while white striping was not different among treatments. The 4L2D treatment resulted in the highest lung glutathione (GSH) concentration. Malondialdehyde (MDA) and GSH concentrations in the heart tissues of broilers from 8L4D and 4L2D were greater than those from 23L1D and 16:8. Glutathione peroxidase (GSH-Px) and superoxide dismutase concentrations were greatest for birds subjected to 16L8D. Heat shock protein 70 was lowest in lung and heart from birds subjected to 8L4D. Thus, shorter and more frequent periods of darkness can be recommended for welfare with little compromise in performance. Keywords: carcass quality, heat shock protein 70, oxidative stress, white strip

Моделирование термодеформационных процессов, протекающих при электродуговом послойном выращивании

Современная промышленность все больше интереса проявляет к аддитивным технологиям во всех сферах производства, поскольку внедрение данных технологий способствует довольно быстрому и экономичному производству металлических изделий сложной формы. В статье представлена численная модель термодеформационных процессов в подложке и в металлическом изделии при электродуговом послойном выращивание

Tau-dependent microtubule disassembly initiated by prefibrillar β-amyloid

Alzheimer's Disease (AD) is defined histopathologically by extracellular β-amyloid (Aβ) fibrils plus intraneuronal tau filaments. Studies of transgenic mice and cultured cells indicate that AD is caused by a pathological cascade in which Aβ lies upstream of tau, but the steps that connect Aβ to tau have remained undefined. We demonstrate that tau confers acute hypersensitivity of microtubules to prefibrillar, extracellular Aβ in nonneuronal cells that express transfected tau and in cultured neurons that express endogenous tau. Prefibrillar Aβ42 was active at submicromolar concentrations, several-fold below those required for equivalent effects of prefibrillar Aβ40, and microtubules were insensitive to fibrillar Aβ. The active region of tau was localized to an N-terminal domain that does not bind microtubules and is not part of the region of tau that assembles into filaments. These results suggest that a seminal cell biological event in AD pathogenesis is acute, tau-dependent loss of microtubule integrity caused by exposure of neurons to readily diffusible Aβ

Modifications of gustatory nerve synapses onto nucleus of the solitary tract neurons induced by dietary sodium-restriction during development

The terminal fields of nerves carrying gustatory information to the rat brainstem show a remarkable amount of expansion in the nucleus of the solitary tract (NTS) as a result of early dietary sodium restriction. However, the extent to which these axonal changes represent corresponding changes in synapses is not known. To identify the synaptic characteristics that accompany the terminal field expansion, the greater superficial petrosal (GSP), chorda tympani (CT), and glossopharyngeal (IX) nerves were labeled in rats fed a sodium-restricted diet during pre- and postnatal development. The morphology of these nerve terminals within the NTS region where the terminal fields of all three nerves overlap was evaluated by transmission electron microscopy. Compared to data from control rats, CT axons were the most profoundly affected. The density of CT arbors and synapses quadrupled as a result of the near life-long dietary manipulation. In contrast, axon and synapse densities of GSP and IX nerves were not modified in sodium-restricted rats. Furthermore, compared to controls, CT terminals displayed more instances of contacts with postsynaptic dendritic protrusions and IX terminals synapsed more frequently with dendritic shafts. Thus, dietary sodium restriction throughout pre- and postnatal development had differential effects on the synaptic organization of the three nerves in the NTS. These anatomical changes may underlie the impact of sensory restriction during development on the functional processing of taste information and taste-related behaviors. J. Comp. Neurol. 508:529–541, 2008. © 2008 Wiley-Liss, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/58547/1/21708_ftp.pd

Developmental Switch in the Contribution of Presynaptic and Postsynaptic NMDA Receptors to Long-Term Depression

NMDA receptor (NMDAR) activation is required for many forms of learning and memory as well as sensory system receptive field plasticity, yet the relative contribution of pre- and postsynaptic NMDARs over cortical development remains unknown. Here we demonstrate a rapid developmental loss of functional presynaptic NMDARs in the neocortex. Presynaptic NMDARs enhance neurotransmitter release at synapses onto visual cortex pyramidal cells in young mice (P21). Immuno-electron microscopy revealed that the loss of presynaptic NMDAR function is likely due in part to a 50% reduction in the prevalence of presynaptic NMDARs. Coincident with the observed loss of presynaptic NMDAR function, there is an abrupt change in the mechanisms of timing-dependent long-term depression (tLTD). Induction of tLTD before the onset of the critical period requires activation of pre- but not postsynaptic NMDARs, while the induction of tLTD in older mice requires activation of postsynaptic NMDARs. By demonstrating that both pre- and postsynaptic NMDARs contribute to the induction of synaptic plasticity, and that their relative roles shift over development, our findings define a novel, and perhaps general, property of synaptic plasticity in emerging cortical circuits

Maternal diet during early gestation influences postnatal taste activity-dependent pruning by microglia

A key process in central sensory circuit development involves activity-dependent pruning of exuberant terminals. Here, we studied gustatory terminal field maturation in the postnatal mouse nucleus of the solitary tract (NST) during normal development and in mice where their mothers were fed a low NaCl diet for a limited period soon after conception. Pruning of terminal fields of gustatory nerves in controls involved the complement system and is likely driven by NaCl-elicited taste activity. In contrast, offspring of mothers with an early dietary manipulation failed to prune gustatory terminal fields even though peripheral taste activity developed normally. The ability to prune in these mice was rescued by activating myeloid cells postnatally, and conversely, pruning was arrested in controls with the loss of myeloid cell function. The altered pruning and myeloid cell function appear to be programmed before the peripheral gustatory system is assembled and corresponds to the embryonic period when microglia progenitors derived from the yolk sac migrate to and colonize the brain