Analysis of microbiota associated with peri-implantitis using 16S rRNA gene clone library

Background: Peri-implantitis (PI) is an inflammatory disease which leads to the destruction of soft and hard tissues around osseointegrated implants. The subgingival microbiota appears to be responsible for peri-implant lesions and although the complexity of the microbiota has been reported in PI, the microbiota responsible for PI has not been identified. Objective: The purpose of this study was to identify the microbiota in subjects who have PI, clinically healthy implants, and periodontitis-affected teeth using 16S rRNA gene clone library analysis to clarify the microbial differences. Design: Three subjects participated in this study. The conditions around the teeth and implants were evaluated based on clinical and radiographic examinations and diseased implants, clinically healthy implants, and periodontally diseased teeth were selected. Subgingival plaque samples were taken from the deepest pockets using sterile paper points. Prevalence and identity of bacteria was analyzed using a 16S rRNA gene clone library technique. Results: A total of 112 different species were identified from 335 clones sequenced. Among the 112 species, 51 (46%) were uncultivated phylotypes, of which 22 were novel phylotypes. The numbers of bacterial species identified at the sites of PI, periodontitis, and periodontally healthy implants were 77, 57, and 12, respectively. Microbiota in PI mainly included Gram-negative species and the composition was more diverse when compared to that of the healthy implant and periodontitis. The phyla Chloroflexi, Tenericutes, and Synergistetes were only detected at PI sites, as were Parvimonas micra, Peptostreptococcus stomatis, Pseudoramibacter alactolyticus, and Solobacterium moorei. Low levels of periodontopathic bacteria, such as Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans, were seen in peri-implant lesions. Conclusions: The biofilm in PI showed a more complex microbiota when compared to periodontitis and periodontally healthy teeth, and it was mainly composed of Gram-negative anaerobic bacteria. Common periodontopathic bacteria showed low prevalence, and several bacteria were identified as candidate pathogens in PI

Head Coverings in the Courtroom: A Question of Respect for the Judge or of Judicial Tolerance?

The Human Rights Centre at Ghent University (the HRC) first initiated the present research while preparing an amicus curiae brief in the Lachiri v. Belgium case before the European Court of Human Rights (ECtHR). The applicant in Lachiri, who was a civil party in legal proceedings concerning the murder of her brother, was denied access to a Brussels courtroom after refusing to remove her Islamic headscarf . Ms. Lachiri’s admission was refused in reliance on Article 759 of the Belgian Judicial Code (Gerechtelijk Wetboek/ Code Judiciaire), which provides that “[t]he audience will attend the sessions with their heads uncovered, respectfully and silently; whatever the judge commands for the maintenance of order will be punctually and immediately executed.” In its third-party intervention, the HRC sought to supply the ECtHR with additional information concerning three points: the debate on the wearing of Islamic headscarves in Belgium, the history, object and purpose of Article 759 of the Belgian Judicial Code, and the scope of the State margin of appreciation in prohibiting religious items of clothing

Síndrome de Stevens-Johnson. Apresentação de Caso Clínico

Introdução: A Síndrome de Stevens-Johnson (SSJ) é uma doença mucocutânea rara e potencialmente fatal, mais frequente no sexo masculino, cuja incidência aumenta com a idade e em determinados grupos de risco. A SSJ e a Necrólise Tóxica Epidérmica (NET) são duas entidades da mesma doença, com severidade diferente. A etiologia não é clara, mas pensa-se que se deva maioritariamente a reacções adversas a fármacos. Caso clínico: Um jovem de 17 anos de idade, sem antecedentes pessoais relevantes, foi observado no Serviço de Urgência por surgimento de lesões maculopapulares, com 3 dias de evolução, dispersas pela face, cavidade oral, tronco e extremidades, com prostração e taquicardia. Foi internado com o diagnóstico de SSJ. Discussão e Conclusões: O SSJ e a NET têm grande morbilidade e considerável mortalidade. O rápido reconhecimento desta identidade, com a remoção do fármaco desencadeador é essencial. A perda da função de barreira da pele, com a consequente alteração da homeostasia, implica muitas vezes a manutenção da terapêutica de suporte em Unidades de Cuidados Intensivos ou de Queimados.info:eu-repo/semantics/publishedVersio

Effect of erbium-doped: yttrium, aluminium and garnet laser irradiation on the surface microstructure and roughness of sand-blasted, large grit, acid-etched implants

Aerospace Engineerin

Long time follow up of implant therapy and treatment of peri-implantitis

POPULÄRVETENSKAPLIG SAMMANSTÄLLNING Dentala implantat har blivit ett ofta använt alternativ för att ersätta förlorade tänder, vilket resulterat i att en ökad andel av den vuxna befolkningen är försedd med implantatförankrad protetik. Trots att fördelaktiga långtidsresultat av implantatbehandling rapporterats förekommer infektioner. Hitintills har endast ett fåtal studier inkluderat data om infektioner runt implantat, vilket troligen lett till att denna komplikation vid implantatbehandling underskattats. Det är möjligt att vissa infektioner runt implantat utvecklas långsamt och att peri-implantit (infektion runt implantat med benförlust) blir en vanlig komplikation vid implantatbehandling, när fler patienter har haft sina implantat en lång tid (>10 år). Det finns begränsad information om hur peri-implantit ska behandlas. Målet med avhandlingen var att studera frekvens av implantatförluster samt förekomst av infektioner runt implantaten i en grupp av patienter som fått Brånemark-implantat installerade för 9-14 år sedan, samt att relatera dessa komplikationer till patient- och implantatspecifika faktorer. Vidare utvärderades tre kirurgiska behandlingsmodeller för peri-implantit. Denna avhandling baseras på sex studier; Studie I-III inkluderar 218 patienter och 1057 implantat som följdes i 9-14 år och utvärderar förekomsten av samt faktorer som kan relateras till implantatförlust och förekomst av samt faktorer relaterade till lesioner runt implantat. 11 Studie IV är en översiktsartikel som beskriver behandling av infektioner runt implantat. Studie V är en prospektiv kohortstudie som inkluderar 36 patienter och 65 implantat och som utvärderar användandet av benersättningsmedel med eller utan resorberbart membran. Studie VI är en fallstudie med 12 patienter och 16 implantat och som utvärderar benersättningsmedel i kombination med resorberbart membran och täckt läkning. Denna avhandling visar att; Efter 9-14 år finns de flesta implantaten kvar i munnen hos patienterna (95.7%). Patienter som förlorat ett implantat förlorar ofta flera. Implantatförlust är relaterat till förekomst av parodontit (röntgenologisk benförlust på >30 % av tänderna). (Studie I) Peri-implantit är en vanlig klinisk företeelse efter 9-14 år. (Studie II) Vid användandet av implantatet som statistisk enhet förklaras en bennivå på ≥3 gängor (1.8 mm) av förekomst av keratiniserad mukosa och pus. På patientnivå förklaras peri-implantit av parodontit och rökning. (Studie III) Djurstudier har visat att re-osseointgration är möjlig. Majoriteten av humanstudierna är fallstudier. Täckt läkning och bentransplantat kan ge benfyllnad i defekter runt implantat. (Studie IV) Kirurgisk behandling av peri-implantit med ett benersättningsmedel eller benersättningsmedel och ett resorberbart membran resulterade i jämförbara kliniska och röntgenologiska förbättringar. (Studie V) Benersättningsmedel i kombination med resorberbart membran och täckt läkning resulterade i defektfyllnad medDental implants have become an often used alternative to replace missing teeth, resulting in an increasing percentage of the adult population with implant supported prosthesis. Although favourable longterm results of implant therapy have been reported, infections occur. Until recently few reports included data on peri-implant infections,possibly underestimating this complication of implant treatment. It is possible that some infections around implants develop slowly and that with time peri-implantitis will be a common complication to implant therapy as an increasing number of patients have had their implants for a long time (>10 years). Data on treatment of periimplant lesions are scarce leaving the clinician with limited guidance regarding choice of treatment. The aim of this thesis was to study the frequency of implant loss and presence of peri-implant lesions in a group of patients supplied with Brånemark implants 9-14 years ago, and to relate these events to patient and site specific characteristics. Moreover three surgical treatment modalities for peri-implantitis were evaluated. The thesis is based on six studies; Studies I-III included 218 patients and 1057 implants followed for 9-14 years evaluating prevalence of, and factors related to implant loss (Paper I) and prevalence of peri-implant infections and related factors (Paper II-III). Study IV is a review describing different treatment modalities of peri-implant infections. Study V is a prospective cohort study involving 36 patients and 65 implants, evaluating the use of a bone substitute with or without the use of a resorbable membrane. Study VI is a case series with 12 patients and 16 implants, evaluating a bone substitute in combination with a resorbable membrane and submerged healing. This thesis demonstrated that: After 9-14 years the survival rates of dental implants are high (95.7%). Implant loss seems to cluster within patients and are related to periodontitis evidenced as bone loss on radiographs at remaining teeth before implant placement. (Paper I) Peri-implantitis is a common clinical entity after 9-14 years. (Paper II) Using the implant as the statistical unit the level of keratinized mucosa and pus were explanatory for a bone level at ≥3 threads (1.8 mm). When the patient was used as a statistical unit a history of periodontitis and smoking were explanatory for periimplantitis. (Paper III) Animal research has demonstrated that re-osseointegration can occur. The majority of human studies were found to be case reports. Using submerged healing and bone transplants, bone fill can occur in peri-implant defects. (Paper IV) Surgical treatment of peri-implantitis using a bone substitute with or without a resorbable membrane resulted in similar pocket depth reduction, attachment gain and defect fill. (Paper V) Bone substitute in combination with a resorbable membrane and a submerged healing resulted in defect fill ≥2 threads (1.2 mm) in 81% of the implants. (Paper VI) In conclusion: 9-14 years after implant installation peri-implant lesions are a common clinical entity. Smokers and patients with a history of periodontal disease are at higher risk to develop periimplantitis. Clinical improvements and defect fill can be obtained with various surgical techniques using a bone substitute

Progression and treatment of experimental peri-implantitis

Peri-implantitis is characterized by inflammatory lesions in peri-implant tissues and loss of supporting bone. The aims of the present series of studies were to analyze (i) spontaneous progression and (ii) the effect of surgical treatment of experimental peri-implantitis at different types of implants. Labrador dogs were used. Implants representing 4 different implant systems; group A (turned; Biomet 3i), B (TiOblast; Astra Tech AB), C (SLA; Straumann) and D (TiUnite; Nobel Biocare) (Study I, II and IV) or with similar geometry and with different surface characteristics (turned/TiUnite; Nobel Biocare AB) (Study III) were placed in the mandible 3 months after tooth extraction. Experimental peri-implantitis was initiated by placement of ligatures and plaque accumulation. The ligatures were removed when about 40-50% of the supporting bone was lost. Plaque formation continued for 6 months in Study I, II and III, while in Study IV surgical therapy including mechanical cleaning of implant surfaces was carried out. Radiographic and clinical examinations were performed. Block biopsies containing implants and their surrounding tissues were obtained and prepared for histological analysis. The bone loss that occurred during the plaque formation period after ligature removal was 1.84 (A), 1.72 (B), 1.55 (C) and 2.78 mm (D). Specimens from all types of implants exhibited extensive inflammatory cell infiltrates and large crater-formed osseous defects (Study I and II). The bone loss that occurred after ligature removal in Study III was significantly larger at TiUnite implants than at turned surface implants. The vertical dimensions of the ICT and the pocket epithelium and the apical extension of the biofilm were significantly larger at TiUnite implants than at turned surface implants (Study III). While bone gain occurred at implants with turned, TiOblast and SLA surfaces, TiUnite implants demonstrated bone loss after treatment of peri-implantitis. Resolution after treatment was achieved in tissues surrounding implants with turned and TiOblast surfaces (Study IV)