Measurement of primary stability of the dental implant and the influence of the implant design

1 SUMMARY Measurement of primary stability of the dental implant and the influence of the implant de- sign Primary stability is the lack of mobility in the bone after an implant insertion and it is conditioned by the quality and quantity of the bone, the surgical technique and the skill of the surgeon. Another element is the micro-design and especially macro-design of the implant, whose influence on the primary stability has not been given sufficient scientific attention. The objective of this report is to analyze the influence of the most commonly used threads for implant stability findings a stress distribution at the interface of the implant - bone and adjacent periimplant bone and mechanical load transfer from the implant to the surrounding bone (mechanical compatibility) for these types of threads. Another objective is the theoretical use of the Finite Element Analysis (FEA) which is used to analyze the influence of the length and diameter of the implant on the primary stability. The practical application is based on clinical studies that have shown a link between the length and diameter of the implant on one side and the primary stability on the other. The results obtained by the FEA confirms that the thread shape of the implant influences the resulting mechanical stress on the bone and the implant,...1 SOUHRN Měření primární stability dentálního implantátu a její ovlivnění designem implantátu Primární stabilita je absence mobility v kostním lůžku po vložení implantátu a je podmíněna kvalitou a kvantitou kosti, chirurgickou technikou a zkušeností chirurga. Dalším prvkem je mikrodesign a zejména makrodesign implantátu, jehož vlivu na primární stabilitu zatím nebyla věnována dostatečná vědecká pozornost. Cílem práce bylo analyzovat vliv nejčastěji používaných závitů na stabilitu implantátů zjištěním rozložení napětí na rozhraní implantát - kost a v přilehlé periimplantátové kosti a mechanického přenosu zatížení z implantátu na okolní kost (mechanické kompatibility) u těchto typů závitu. Dalším cílem bylo v teoretické rovině pomocí metody konečných prvků analyzovat vliv délky a průměru implantátu na jeho primární stabilitu. V praktické části bylo cílem na základě klinické studie odhalit souvislost mezi délkou implantátu a jeho průměrem na straně jedné a primární sta- bilitou na straně druhé. Výsledky získané metodou konečných prvků potvrzují, že tvar závitu implantátu ovlivňuje výsledné mechanické napětí v kosti i implantátu, nelze však jednoznačně stanovit nejvhodnější typ závitu implantátu. Dále bylo zjištěno, že v matematickém modelu vlastní frekvence rozkmitaných implantátů stoupají prakticky lineárně,...Stomatologická klinikaDepartment of DentistryLékařská fakulta v Hradci KrálovéFaculty of Medicine in Hradec Králov

Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

Summary Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

Measurement of primary stability of the dental implant and the influence of the implant design

1 SUMMARY Measurement of primary stability of the dental implant and the influence of the implant de- sign Primary stability is the lack of mobility in the bone after an implant insertion and it is conditioned by the quality and quantity of the bone, the surgical technique and the skill of the surgeon. Another element is the micro-design and especially macro-design of the implant, whose influence on the primary stability has not been given sufficient scientific attention. The objective of this report is to analyze the influence of the most commonly used threads for implant stability findings a stress distribution at the interface of the implant - bone and adjacent periimplant bone and mechanical load transfer from the implant to the surrounding bone (mechanical compatibility) for these types of threads. Another objective is the theoretical use of the Finite Element Analysis (FEA) which is used to analyze the influence of the length and diameter of the implant on the primary stability. The practical application is based on clinical studies that have shown a link between the length and diameter of the implant on one side and the primary stability on the other. The results obtained by the FEA confirms that the thread shape of the implant influences the resulting mechanical stress on the bone and the implant,..