Causes and consequences of temporomandibular joint diseases

Temporomandibular joint disorders (TMJD), a subgroup of Temporomandibular disorders (TMD), has a multifactorial etiology with still largely unknown pathophysiology. Although many risk factors have been proposed, few population-based studies have been conducted. There are known associations between TMJD and mental and behavioral disorders (MBD) and musculoskeletal diseases (MSD). MBD and MSD cause high work disability and are the leading causes for sick leave (SL) and disability pension (DP) both globally and in Sweden. However, no studies have investigated work disability among patients with TMJD (pwTMJD) or the effect of MBD and MSD comorbidity on work disability among pwTMJD. This thesis includes all Swedish citizens aged ≥18 registered between 1998 and 2016 in the National Patient Registry with a TMJD diagnosis or TMJD surgical procedure code. These pwTMJD (n=33 316) were matched to a comparison cohort (n=333 160) from the Total Population Registry. pwTMJD were categorized depending on whether they had received surgical treatment or not, and on the number of surgical procedures. Study I shows that pwTMJD have 2–3 times more mean annual days of SL and DP than the general population and that patients who had undergone several surgical treatments were most dependent on these benefits. The increased work disability among pwTMJD was noticeable as early as five years before first time diagnosis or treatment. Study II and Study III investigate the probability of developing TMJD among individuals with and without MBD/MSD. Study II shows that many MBD increase the probability of TMJD and that individuals with MBD had a higher risk of needing repeated surgical procedures compared to individuals with no MBD. Study III shows that virtually all MSD increase the probability of TMJD, especially TMJD that require repeated surgical procedures. Study IV further examines the impact of MBD and MSD comorbidity on mean annual days of SL and DP among pwTMJD compared to the general population, by using strata of comorbidity. The results show that both MBD and MSD comorbidity by themselves have a large impact on the use of social insurance benefits but that combined MBD/MSD comorbidity had the largest impact on SL and DP. Regardless of comorbidity, pwTMJD displayed the highest mean annual days of SL and DP in almost all strata of comorbidity. In conclusion, the results in this thesis show that MBD and MSD are strong predictors for the development of TMJD. The results also show that pwTMJD have more work disability than the general population, and that this increased dependence on social insurance benefits is strongly influenced by comorbidities. These findings emphasize how pwTMJD are suffering from their condition and that a multimodal approach is warranted, preferably steered by national guidelines designed by specialists in orofacial pain and function, oral and maxillofacial surgeons, and colleagues from the medical field

Europa 2020-strategin och kommunerna : en fallstudie om kommunernas inställning till implementering av Sveriges nationella mål

Purpose: The Swedish Government considers it is important that both the local and regional level integrates the Europe 2020 strategy. The government expresses that the local municipality level has a central role to achieve some of the Swedish country-specific recommendations. The aim is to increase the understanding of the municipalities’ attitudes towards implementation of the Swedish country-specific recommendations. Question: What attitude do examined municipalities have towards implementation of the Swedish country-specific recommendations? Methodology: The paper’s methodological approach is a qualitative research method with a case study research design. Theories: The theoretical framework consists of four theories: Reasons to implementation issues, such as the interest-, resource- and priority issue, and a one theory about local democracy and one theory about the representation and function of the local municipalities. Empirical evidence: The primary data consists of eight semi-structured interviews, one politician and one none political official from four different municipalities. Empirical research examines attitudes towards implementation of the Swedish country-specific recommendations. Conclusion: The Swedish country-specific recommendations must be locally accepted in order to get implemented in the municipalities’ local visions/goals. The municipalities prioritize local needs and the Swedish country-specific recommendations are often secondly prioritized

Hur interagerar travhästens hov med olika banunderlag?

SAMMANFATTNING Underlagets egenskaper och preparering påverkar hästens prestation och hållbarhet. En allmän uppfattning är att travhästarna presterar sämre på fibersandsunderlag än en traditionell travbana med sand, men tidigare studier har indikerat olika resultat. I denna studie har biomekaniska event mätts med höghastighetsfilmning på travhästar som har travat i 80 %, 90 % och 100 % av sin maxkapacitet på tre olika underlag (vaxad fibersand som preparerats på två sätt, samt en traditionell travbana av sand). Hovens uppbromsningslängd och -tid, steglängd, hastighet och stegfrekvens har analyserats. Underlagets egenskaper har mätts med en fallhejarbaserad mekanisk hov (OBST) som efterliknar hovens interaktion med marken och beskriver underlaget efter fem parametrar: ytfasthet, dämpning, elasticitet, grepp och enhetlighet. I detta examensarbete redovisas ytfasthet (vertikal acceleration) och dämpning (maximal belastning). När hästarna travade i sin maximala kapacitet, nådde de en högre hastighet på det vaxade fibersandsunderlaget än på den traditionella travbanan. Den måttligt kompakterade fibersandbanan visade längst uppbromsningstid och kortast uppbromsningslängd. Den traditionella travbanan gav motsatt resultat. Dessa värden kan användas som ett mått på den kraft som uppstår under hovens uppbromsning. Den traditionella travbanans underlag hade avsevärt högre värden för maximal belastning (dämpning) och ytfasthet än underlagen med vaxad fibersand. Detta indikerar att vaxad fibersand skulle kunna ha en minskad risk för skador i hästens rörelseapparat. Hur banunderlag preparerats har en viktig betydelse i vilka egenskaper underlaget får. Studien visar att vaxat fibersandsunderlag kan prepareras på så sätt att den påminner om den traditionella travbanan. Fortsatta studier som mäter underlagets egenskaper i relation till biomekaniska event skulle kunna leda till utveckling av travbanor med underlag som ökar både prestation och hållbarhet.SUMMARY Track surface properties can affect both performance and risk of orthopedic health injuries of the horse. It is general supposed that synthetic track surface decrease trotter’s performance compare to traditional crushed sand track. However, earlier studies indicate different results. In this study biomechanical parameters on trotters was measured by high speed cameras when the horses trotted in three different speeds (80 %, 90 % and 100 % of their maximal capacity) on three different track surfaces (synthetic waxed track prepared in two different ways and traditional crushed sand). Hoof break time, hoof break length, stride length, velocity and stride frequency was analyzed. Properties of the ground was measured by an Orono Biomechanical Surface Tester (OBST), a mechanical hoof that mimics the hoof and ground interaction and describe the properties of the surface in 5 parameters: impact firmness, cushioning, responsiveness, grip and uniformity. This master’s thesis describe impact firmness (vertical acceleration) and cushioning (maximal load). Horses trotting in maximal capacity achieved higher speeds on synthetic vexed track compare to crushed sand. The longest hoof break time and shortest hoof break length was on the moderately compacted synthetic vaxed track. Crushed sand track indicated opposite results. These results can be used when measure hoof break force. Crushed sand has considerably higher values for maximal load and impact firmness compare to synthetic vaxed track, thus indicate synthetic vaxed track may reduce risk of musculoskeletal injuries. Preparation procedures on a track surface effect its properties. This study indicate that synthetic waxed track can be prepared in a way that the properties became similar to crushed sand track surfaces. Further studies to measure the properties of the ground in correlation to biomechanical parameters should develop track surfaces thus stimulate both performance and orthopedic health

Spatial scaling of population synchrony in marine fish depends on their life history

The synchrony of population dynamics in space has important implications for ecological processes, for example affecting the spread of diseases, spatial distributions and risk of extinction. Here, we studied the relationship between spatial scaling in population dynamics and species position along the slow‐fast continuum of life history variation. Specifically, we explored how generation time, growth rate and mortality rate predicted the spatial scaling of abundance and yearly changes in abundance of eight marine fish species. Our results show that population dynamics of species' with ‘slow’ life histories are synchronised over greater distances than those of species with ‘fast’ life histories. These findings provide evidence for a relationship between the position of the species along the life history continuum and population dynamics in space, showing that the spatial distribution of abundance may be related to life history characteristics.acceptedVersio