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Tuesday, May 16, 2023

05-16-2023-1651 - Šoštanj, mass graves, carinthia, pulp stone, etc. (draft)

Mass graves

Šoštanj is the site of four known mass graves and one unmarked grave from the period immediately after the Second World War. The Gorica 1–4 mass graves (Slovene: Grobišče Gorica 1–4) all lie north of Lake Šoštanj. The first grave is also known as the Čebul Meadow Mass Grave (Grobišče Čebulov travnik).[6] The second grave is also known as the Stvarnik Meadow Mass Grave (Grobišče na Stvarnikovi njivi) or the Bodjan Meadow Mass Grave (Grobišče na Bodjanovi njivi).[7] The four graves contain the remains of Slovene, Croatian, and German civilians that were murdered on the Gorica Ridge northeast of the town in late May 1945 as they were fleeing to Carinthia. The victims include a group of wealthy Šoštanj residents murdered on 23 May 1945.[8][9] The graves are part of the same set as the Družmirje 1 and 2 mass graves. The Janez Pirmanšek Grave (Grob Janeza Pirmanška) lies in a meadow west of the town, at Primorska Cesta no. 7, above the sawmill and log storage area. A memorial to Šoštanj residents that fell while serving in the German army formerly stood at the site. The grave contained the remains of the Slovene civilian Janez Pirmanšek, who was liquidated on 20 May 1945.[10] 

https://en.wikipedia.org/wiki/%C5%A0o%C5%A1tanj#Mass_graves

Power plant

Main article: Šoštanj Power Plant

The Šoštanj Power Plant began producing electricity in 1956.[11] The plant is partly sponsored by the European Bank for Reconstruction and Development and the European Investment Bank, and is highly controversial.[12] 

https://en.wikipedia.org/wiki/%C5%A0o%C5%A1tanj#Power_plant

A lignite stockpile (above) and a lignite briquette

Lignite, often referred to as brown coal,[1] is a soft, brown, combustible, sedimentary rock formed from naturally compressed peat. It has a carbon content around 25–35%,[1][2] and is considered the lowest rank of coal due to its relatively low heat content. When removed from the ground, it contains a very high amount of moisture which partially explains its low carbon content. Lignite is mined all around the world and is used almost exclusively as a fuel for steam-electric power generation.

The combustion for lignite produces less heat for the amount of carbon dioxide and sulfur released than other ranks of coal. As a result lignite is the most harmful coal to human health.[3] Depending on the source, various toxic heavy metals, including naturally occurring radioactive materials may be present in lignite which are left over in the coal fly ash produced from its combustion, further increasing health risks.[4]

https://en.wikipedia.org/wiki/Lignite

Description

There are currently five units in the TEŠ (Termoelektrarna Šoštanj) power plant, which is owned by Holding Slovenske Elektrarne (HSE). Units 1 and 2 have closed down, and units 3, 4, and 5 were planned to be shut down around 2016. The TEŠ6 is the newest unit of the project, made to replace the old technology of the previous units. The newest edition is said to increase the power generated by 30%. This new unit will hold around 600 megawatts of electricity.[13] The plant's operations will last for 40 years, 6650 hours annually, and will consume 440 metric tonnes of lignite per hour.[14]

The TEŠ6 was proposed in 2003 and was included in the Slovenian government's agenda around 2007. The cost of TEŠ6 has climbed to around 1.5 billion euros due to the 50 million euro annual losses.[15] The European Investment Bank (EIB) has given 550 million euros, the European Bank for Research and Development (EBRD) has given approximately 200 million euros, 515 million euros from the owner's capital, 83 million euros from HSE, and 80 million euros from a commercial loan.[14] 

https://en.wikipedia.org/wiki/%C5%A0o%C5%A1tanj#Power_plant

X-ray manual - U.S. Army (1917) (14734336166).jpg

Pulp stones (also denticles or endoliths)[1] are nodular, calcified masses appearing in either or both the coronal and root portion of the pulp organ in teeth. Pulp stones are not painful unless they impinge on nerves.

They are classified:[2]

A) On the basis of structure
1) True pulp stones: formed of dentin by odontoblasts
2) False pulp stones: formed by mineralization of degenerating pulp cells, often in a concentric pattern
B) On the basis of location
1) Free: entirely surrounded by pulp tissue
2) Adherent: partly fused with dentin
3) Embedded: entirely surrounded by dentin

Introduction

Pulp stones are discrete calcifications found in the pulp chamber of the tooth which may undergo changes to become diffuse pulp calcifications such as dystrophic calcification.[2] They are usually noticed by radiographic examination and appeared as round or ovoid radiopaque lesions.[3] Clinically, a tooth with a pulp stone has normal appearance like any other tooth.[4] The number of pulp stones in a single tooth may vary from 1 to 12 or more, with varying sizes from minute particles to large masses which tend to occlude the pulpal space. It is reported that pulp stones are more commonly found in the coronal region of pulp, albeit also found in the radicular pulp.[2]

It is believed that pulp stones develop around a central nidus of pulp tissue, for instance collagen fibril, ground substance and necrotic cell remnants. Initial calcification occurs around the central nidus and extends outward with regular calcified material in a concentric or radial manner.[5]

Etiology

The pulp calcifications can arise due to:

It is shown that pulp stone occurring in adolescents is significantly associated with carious and/or restored teeth, which suggests a causative relationship of chronic pulp irritation to pulp stone formation. A defence reaction in the pulpodentinal complex may be triggered by caries and microleakage around restorations which lead to pulp calcifications. The formation of pulp stone may have a similar mechanism as the tertiary dentine formation near the irritated odontoblasts. Apart from that, with aging, the pulp decreases in size due to the deposition of secondary or tertiary dentine. This subsequently results in favourable conditions for the formation of pulpal calcifications.

The other reported etiologic factors also include:

Types/classification

Pulp stones can be classified based on different location and structure.[2]

Based on location, they can classified into free, embedded and adherent pulp stones. Free pulp stones are found within the pulp tissue and is the most common encounter. The size vary from 50μm in diameter to several millimetres and may occlude the entire pulp chamber. Embedded pulp stone is fully embedded in dentine and most commonly found in the apical portion of the root. Adherent pulp stones are attached to the wall of pulp space but not fully enclosed by dentine.

Structurally, pulp stones can be classified as true and false pulp stones. True pulp stones are made up of dentine that is lined by odontoblast. True pulp stones are quite rare. On the other hand, false pulp stones are made up of concentric layers of mineralised tissue around blood thrombi, collagen fibres, or dying and dead cells.

Histopathology

Histologically, there are two types of stones: (1) stones with regular calcifications (2) stones with irregular calcifications.  For regular calcification, the pulp stones are smooth, round or ovoid with concentric laminations. It is commonly found in the coronal pulp. As for irregular calcifications without laminations, pulp stones may have the shape of rods or leaves and the surface is rough. It is more common in the radicular pulp. Pulp stones with regular calcification grow in size by addition of collagen fibrils to their surface, whereas the irregular type of pulp stones are formed by calcification of pre-existing collagen fibres.

Pulp stones may also form around epithelial cells such as remnants of Hertwig's epithelial root sheath. It is presumed that epithelial remnants are able to induce adjacent mesenchymal stem cells to differentiate into odontoblasts.[7]

Associations

A pilot study was done with patients with cardiovascular disease (CVD) and it shows increased incidence of pulp stones in teeth with patients with CVD compared to healthy patients without CVD.[8] There are also researchers which suggest the link between pulpal calcification and carotid artery calcification, despite not having a strong proof on this correlation.[5] Besides cardiovascular disease, other disease such as end stage renal disease, Marfan syndrome, Ehlers-Danlos syndrome, Calcinosis universalis, tumoral calcinosis are also discovered to be in association with pulpal calcifications.[9]

Several genetic diseases such as dentin dysplasia and dentinogenesis imperfecta are also accompanied by pulpal calcifications and hence, Marfan syndrome was suspected to be in association with pulp stones due to abnormal dentin formation, leading to the increased frequency of pulpal calcifications in these individuals.[9] Another theory suggests that individuals with Marfan syndrome have connective tissue dysplasia or vascular defects which in the case of tooth pulp, endothelial rupture of the pulp arterioles will lead to hemorrhagic areas in the pulp. It was proposed that these hemorrhagic areas in the pulp will induce mineralization within the pulp.[9]

Prevalence

Pulpal calcifications can be developed throughout the life and prevalence rates from 8–9% in worldwide population had been reported in studies. It was also found that pulpal stones occurred most frequently over the fourth decade, in advancing age.[10][5]

Generally, pulp stones are more frequent to be found in maxillary teeth compared to mandibular teeth.[11] A study in Australia resulted higher occurrences of pulp stones in molars as opposed to premolars, and first molars as opposed to second molars.[6] First molars which were restored and/or with caries showed a higher incidence of pulp stones as compared to intact, unrestored first molars.

Clinical implications

Pulp stones generally do not have significant clinical implications as they are usually not a source of pain, discomfort or any form of pulpitis.[5][12] However, when the tooth concerned will undergo endodontic treatment such as root canal treatment, presence of large pulp stones will be clinically significant.[12][13]

Large pulp stones in the pulp chamber might block the access to canal orifices and prevent the exploring dental instruments from passaging down the canal.[12] In these cases, burs or even ultrasonic instrumentation can be used to remove the blocking pulp stones.[12] During the removal process, sodium hypochlorite which has dissolving action can also be used as a synergistic effect.[14]

References


  • Mosby's Medical Dictionary (9th ed.). Elsevier Health Sciences. 2013. p. 507. ISBN 978-0323112581. Retrieved 10 February 2016.

  • Goga R, Chandler NP, Oginni AO (June 2008). "Pulp stones: a review" (PDF). International Endodontic Journal. 41 (6): 457–68. doi:10.1111/j.1365-2591.2008.01374.x. PMID 18422587.

  • Feng XJ, Luo X, Li R, Dong W, Qi MC (August 2015). "[Multiple pulp stones: report of a case and literature review]". Shanghai Kou Qiang Yi Xue = Shanghai Journal of Stomatology. 24 (4): 511–2. PMID 26383583.

  • Berès F, Isaac J, Mouton L, Rouzière S, Berdal A, Simon S, Dessombz A (March 2016). "Comparative Physicochemical Analysis of Pulp Stone and Dentin" (PDF). Journal of Endodontics. 42 (3): 432–8. doi:10.1016/j.joen.2015.11.007. PMID 26794341.

  • Neville BW, Damm DD, Allen CM, Chi AC (2015-05-13). Oral and maxillofacial pathology (Fourth ed.). St. Louis, MO. ISBN 9781455770526. OCLC 908336985.

  • Kannan S, Kannepady SK, Muthu K, Jeevan MB, Thapasum A (March 2015). "Radiographic assessment of the prevalence of pulp stones in Malaysians". Journal of Endodontics. 41 (3): 333–7. doi:10.1016/j.joen.2014.10.015. PMID 25476972.

  • Cohen's Pathway of Pulp.

  • Edds AC, Walden JE, Scheetz JP, Goldsmith LJ, Drisko CL, Eleazer PD (July 2005). "Pilot study of correlation of pulp stones with cardiovascular disease". Journal of Endodontics. 31 (7): 504–6. doi:10.1097/01.don.0000168890.42903.2b. PMID 15980708.

  • Bauss O, Neter D, Rahman A (December 2008). "Prevalence of pulp calcifications in patients with Marfan syndrome". Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontics. 106 (6): e56–61. doi:10.1016/j.tripleo.2008.06.029. PMID 18805711.

  • Udoye C, Sede M (January 2011). "Prevalence and analysis of factors related to ooccurrence of pulp stone in adult restorative patients". Annals of Medical and Health Sciences Research. 1 (1): 9–14. PMC 3507086. PMID 23209949.

  • Hsieh CY, Wu YC, Su CC, Chung MP, Huang RY, Ting PY, Lai CK, Chang KS, Tsai YW, Shieh YS (June 2018). "The prevalence and distribution of radiopaque, calcified pulp stones: A cone-beam computed tomography study in a northern Taiwanese population". Journal of Dental Sciences. 13 (2): 138–144. doi:10.1016/j.jds.2017.06.005. PMC 6388828. PMID 30895109.

  • Goga R, Chandler NP, Oginni AO (June 2008). "Pulp stones: a review". International Endodontic Journal. 41 (6): 457–68. doi:10.1111/j.1365-2591.2008.01374.x. PMID 18422587.

  • Regezi JA, Sciubba J, Jordan RC (2012). "Abnormalities of Teeth". Oral Pathology: Clinical Pathologic Correlations (6th ed.). Elsevier. pp. 373–389. doi:10.1016/b978-1-4557-0262-6.00016-1. ISBN 9781455702626.

    1. Ertas ET, Veli I, Akin M, Ertas H, Atici MY (January 2017). "Dental pulp stone formation during orthodontic treatment: A retrospective clinical follow-up study". Nigerian Journal of Clinical Practice. 20 (1): 37–42. doi:10.4103/1119-3077.164357. PMID 27958244. S2CID 4873355.

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