ANALISI IMMUNOISTOCHIMICA E MOLECOLARE DEL PATTERN DI RIMODELLAMENTO OSSEO NELL¿ALVEOLO POST-ESTRATTIVO

Analisi immunoistochimica e molecolare del pattern di rimodellamento osseo nell\u2019alveolo post-estrattivo SCOPO Il sito dell\u2019alveolo post-estrattivo \ue8 un modello ampiamente utilizzato nello studio del rimodellamento osseo fisiologico o patologico e del comportamento di biomateriali per la rigenerazione ossea. Lo scopo di questo progetto \ue8 stato quello di caratterizzare il pattern morfologico e molecolare dei marker coinvolti nel rimodellamento osseo alveolare, prima e dopo l\u2019estrazione dentale, ed eventualmente in combinazione con un biomateriale utilizzato per preservare l\u2019anatomia del sito ai fini riabilitativi. MATERIALI E METODI Per questo studio sono stati arruolati 36 pazienti, suddivisi in 3 gruppi indipendenti: osso alveolare (OA, n=14), guarigione spontanea (GS, n=10) e biomateriale (B, n=12). Durante la seduta di estrazione dentaria sono state raccolte 2 piccole biopsie per paziente per effettuare l\u2019analisi morfologica (tessuto decalcificato) e molecolare (mRNA retro-trascritto in cDNA e Real Time-PCR) (gruppo OA). Dopo 4-6 mesi dall\u2019estrazione dentale, sono state prelevate 3 biopsie per paziente, in concomitanza dell\u2019inserimento dell\u2019impianto dentale, nel sito guarito spontaneamente (GS) o mediante biomateriale (B) (idrossiapatite arricchita con magnesio). Per ogni gruppo sono state effettuate le stesse analisi del gruppo OA e l\u2019analisi istomorfometrica (tessuto calcificato). L\u2019analisi morfologica ha previsto: colorazione Ematossilina/Eosina per osservare un eventuale infiltrato infiammatorio, colorazione immunoistochimica dei fattori caratterizzanti il pattern di rimodellamento osseo (TNF-\u3b1, IL-6, RANK, RANKL e OPG), espressa come marcatura percentuale. L\u2019analisi molecolare \ue8 stata effettuata sugli stessi marcatori normalizzati sul gene housekeeping 18S. Sui tessuti ottenuti per usura, \ue8 stata valutata l\u2019osteointegrazione del biomateriale e la componente minerale mediante la valutazione delle frazioni di volume (stereologia). Per ciascun parametro sono state calcolate la media e la deviazione standard; \ue8 stato utilizzato il test di Kruskal Wallis (p<0,05) per valutare le eventuali differenze tra i 3 gruppi per ogni parametro e successivo test post hoc di Wilcoxon (p< 0,05/3). RISULTATI All\u2019osservazione i campioni raccolti non presentavano n\ue9 anomalie strutturali n\ue9 infiltrato infiammatorio. Sia l\u2019analisi immunoistochimica (AI) che molecolare (AM) ha mostrato un incremento per tutti i biomarker. AI: I tre gruppi erano significativamente differenti per il marcatore TNF-\u3b1 (p<0.05), RANK (p<0.01), IL-6 e RANKL (p<0.001). Il test post hoc ha mostrato una differenza tra OA e B per RANK (p 64 0.01), IL-6 e RANKL (p 640.001); tra GS e B per IL-6 (p 640.01). AM: Il test di Kruskal Wallis ha mostrato differenze tra i gruppi per IL-6 (p 640.05), RANKL e OPG (p 640.001); il test post hoc ha riscontrato una significativa differenza tra OA e B per IL-6 (p 640.01); OA e GS per RANKL e OPG (p 640,001); tra GS e B per IL-6 e RANKL (p 640,01), OPG (p 640,001). Il rapporto RANKL/OPG ha mostrato una tendenza alla riduzione dell\u2019osteoclastogenesi nel gruppo B. L\u2019analisi istomorfometrica ha mostrato un\u2019alta percentuale di componente mineralizzata nel gruppo con il biomateriale; tutte le particelle innestate erano circondate da osso rigenerato che creava ponti tra di esse. CONCLUSIONI Rispetto al rimodellamento fisiologico tutti i marker indagati hanno mostrato un incremento in entrambi i gruppi in fase di guarigione dell\u2019alveolo post-estrattivo. Nei siti trattati con il biomateriale si \ue8 osservato un aumento della citochina IL-6 ed una diminuzione di RANK, RANKL e OPG rispetto alla guarigione spontanea. Questo pu\uf2 significare un rallentamento della ricostituzione del sito anatomico, dovuto ad una possibile down-regulation dell\u2019osteoclastogenesi. Tuttavia, l\u2019analisi della struttura dell\u2019alveolo ha mostrato una buona rigenerazione ossea, in entrambi i gruppi; pertanto il biomateriale analizzato pu\uf2 essere considerato un valido ausilio per la preservazione dell\u2019alveolo post-estrattivo.Immunohistochemical and molecular analysis of bone remodelling pattern in alveolar socket. AIM Following tooth extraction, the alveolar bone remodelling process starts. The aim of this research project was to characterize the molecular and morphological aspects of the alveolar bone remodelling pattern before and after dental extraction and in conjunction with the use of hydroxyapatite enriched with magnesium (Mg-e HA) to preserve the post-extractive alveolar socket. MATERIALS AND METHODS Thirty-six patients, divided in three groups, were enrolled in this study. The studied groups were: alveolar bone (OA, n=14), spontaneous healing (GS, n=10) and biomaterial (B, n=12). The biopsies for morphological and molecular analyses were harvested during the extraction tooth session (group OA) or 4-6 months later (GS, B). In GS group, patients recovered spontaneously, while in B group Mg-e HA granules were grafted to avoid the collapse of post-extraction socket. For each group, one specimen was processed for Haematoxylin and Eosin staining and immunohistochemistry for TNF-\u3b1, IL-6, RANK, RANKL and OPG. Another specimen was processed to evaluate the gene expression of the same biomarkers by Real-Time PCR (mRNA retro-transcript into cDNA). Data were normalized on housekeeping gene 18s. In GS and B groups, ground sections were obtained to evaluate the mineral component by mean of stereological analyses. For each parameter, statistical analyses were performed to evaluate the differences among the three groups (Kruskal Wallis, significance for p<0.05); post hoc tests were made by Wilcoxon tests (p<0.05/3). RESULTS Samples harvested from each group presented a normal structure, without evident inflammatory infiltrate. Immunohistochemical (IA) and molecular analysis (MA) showed an increment for all biomarkers. IA: The three groups were significantly different for markers TNF-\u3b1 (p<0.05), RANK (p<0.01), IL-6 e RANKL (p<0.001). Post hoc tests showed a difference between OA and B for RANK (p 64 0.01), IL-6 and RANKL (p 640.001); between GS and B for IL-6 (p 640.01). MA: Kruskal Wallis test showed a difference among groups for IL-6 (p 640.05), RANKL and OPG (p 640.001); post hoc tests revealed a significant difference between: OA and B for IL-6 (p 640.01); OA and GS for RANKL and OPG (p 640.001); GS and B for IL-6 and RANKL (p 640.01), OPG (p 640.001). RANKL/OPG ratio showed a tendency towards a reduced osteoclastogenesis in group B. Histomorphometry revealed a high percentage of mineralized tissue in the grafted sites; all the residual granules were surrounded by newly formed bone, consisting in regenerated bone bridges. CONCLUSION Both post-extractive groups had an increase of all analysed biomarkers in respect of the physiological remodelling pattern. In the grafted sites, IL-6 values were higher than in the spontaneous healing group; in contrast RANK, RANKL and OPG were slightly lower. The present data may suggest a slowing down in the restoration of the anatomical site, possibly due to a down regulation in the osteoclastogenesis. However, the tissue composition of the grafted alveolar socket showed a good bone regeneration in both groups. Therefore, the current biomaterial could be considered a useful tool for alveolar socket preservation

Antimicrobial activity of zinc-doped hydroxyapatite coatings formed on titanium Ti6A14V surface for orthopedic implant

Prosthetic joint infection (PJI) is one of the most serious complications of prosthetic joint implantation leading to a longer hospitalization. S. aureus is the predominant cause of PJI followed by Pseudomonas aeruginosa and Stafilococci spp. coagulase negative. Several studies focused on the development of effective antibacterial surfaces that prevent bacterial adhesion, colonisation and proliferation into the surrounding tissues and it has been widely demonstrated that zinc ions (Zn2+) exhibit antimicrobial activity against various bacterial and fungal strains. In addition to its antimicrobial activities, zinc is important in healthy bone growth and development. The aim of this study was to evaluate the in vitro activity of Zn2+ generated from the partial dissolution of Zn particles on surface of titanium discs, against S. aureus ATCC 29213. Hydroxyapatite (HA), and HA/Zn2+ doped discs were used. Each disc was incubated with bacterial suspension following standard ASTM (American Society for Testing and Materials) method. After, colony-forming unit (CFU) were counted. The results showed 1,7 log10 (97,8 %) CFU decrease vs untreated samples (p&lt; 0.05), after 6 hours of incubation. To confirm quantitative data, morphological analysis was performed by Scanning Electron Microscope (SEM). On HA disc, bacteria, recognized by the typical spherical shape, colonized micro and nano porosities surface assuming an homogeneous distribution, while on the surface doped with Zn2+, being smoother and less porous, the bacteria adhered to the surface in small colonies of about 2-10 bacteria. This new formulation of zinc coating could represent a promising approach for prevention and treatment of peri-implant diseases

An amino acid mixture, enriched with Krebs cycle intermediates, enhances extracellular matrix gene expression in cultured human fibroblasts

: In the human body, the skin is one of the organs most affected by the aging process. Nutritional approaches aimed to counteract the age-induced decline of extracellular matrix (ECM) deposition could be a valuable tool to decrease the degenerative processes underlying skin aging. Here, we investigated the ability of a six-amino acid plus hyaluronic acid (6AAH) formulation enriched with tricarboxylic acid (TCA) intermediates to stimulate ECM gene expression. To this aim, human BJ fibroblasts were treated with 6AAH alone or plus succinate or malate alone or succinate plus malate (6AAHSM), and mRNA levels of several ECM markers were evaluated. 6AAHSM increased the expression of all the ECM markers significantly above 6AAH alone or plus only succinate or malate. Furthermore, in an in vitro oxidative damage model, 6AAHSM blunted the hydrogen peroxide-induced decline in ECM gene expression. Our data suggest that feeding cells with 6AAH enriched with TCAs could efficiently be employed as a non-pharmacological approach for counteracting skin aging

Implant surfaces exposed to the oral cavity and treated with toothpaste containing oxygen releasing compound : a morphological controlled clinical trial

Aim of the present in vivo study is to assess if a toothpaste containing an oxygen releasing compound (AX) is able to reduce the biofilm formation on implants with rough surface compared to a control toothpaste, without affecting the microstructure of the tested surface. Methods: In this double blind, cross-over, controlled clinical trial, a total of fourteen healthy volunteers were recruited. For each subject, two mandibular splints (test and control) were created with one implant fixed on the right lingual side of the mandibular arch. The splint was continuously worn for 5 days and the daily hygiene was performed wearing the splint and using the test (AX) or control toothpaste. Implants were analyzed at scanning-electron-microscopy and at laser profilometer for the assessment of biofilm adhesion (% of areas free from biofilm-FA) and surface changes (morphology and roughness). Results: FA resulted significantly higher in test than in control implants. No differences were found between groups in term of biofilm organization, surface microstructure and roughness. Discussion: Daily use of toothpaste containing AX seems to reduce the amount of biofilm adherent to the rough implant surface without corrosion or degradation of the titanium surface

Dental treatment of a rare case of pyoderma gangrenosum with aggressive periodontal disease

Background and Overview: Pyoderma gangrenosum (PG) is a rare neutrophil-mediated autoinflammatory dermatosis that can involve the oral mucosa. Dental surgery is a potential triggering factor for the onset of PG lesions. The authors describe and discuss the dental management of a rare case of aggressive periodontitis in a patient with PG, from multiple tooth extractions to prosthetic rehabilitation, including administration of systemic steroid prophylaxis before surgery to prevent the potential onset of PG-related lesions. Case Description: A 22-year-old man who had a diagnosis of PG and who had aggressive periodontal disease underwent dental extractions, gingivoplastic surgery, and prosthetic rehabilitation. The patient received 8 milligrams of betamethasone intramuscularly 20 minutes before the oral surgery. The tissues healed perfectly, and no adverse effects were reported. Conclusions and Practical Implications: For minor oral surgery, prophylactic corticosteroids might help reduce the risk of developing PG-related lesions. The clinician should plan the prosthetic devices to be as atraumatic as possible

Arm position as a source of error in blood pressure measurement

The present study was designed to assess the value of correct positioning of a patient's arm when measuring blood pressure (BP). A total of 181 subjects were examined, 141 hypertensives on treatment, 25 untreated hypertensives, 15 normotensives. All the subjects underwent three BP measurements after a 5-min resting period in supine position. Then two BP readings were recorded in standing position with the arm either positioned by the patient's side or supported passively at patient's heart level. Average systolic BP (SBP) in standing position were 144.6 +/- 20.2 mmHg with the arm at the side and 136.4 +/- 21.1 mmHg with the arm at the heart level (p less than 0.001); average diastolic pressures were 99.0 +/- 12.0 mmHg and 90.2 +/- 12.3 mmHg (p less than 0.001), respectively. A fall in SBP greater than or equal to 20 mmHg from the supine to the upright position was detected in 18.2% of cases when measurement was performed at heart level; such a reduction was inapparent in two-thirds of cases when the arm was placed at the patient's body side. Incorrect positioning of a patient's arm during BP measurements in standing position leads to overestimation of BP values and masks the presence of postural hypotension

High-throughput screening for modulators of ACVR1 transcription: discovery of potential therapeutics for fibrodysplasia ossificans progressiva.

open12noopenCappato, S; Tonachini, L; Giacopelli, F; Tirone, M; Galietta, Lj; Sormani, M; Giovenzana, A; Spinelli, Antonello E.; Canciani, B; Brunelli, S; Ravazzolo, R; Bocciardi, R.Cappato, S; Tonachini, L; Giacopelli, F; Tirone, M; Galietta, Lj; Sormani, M; Giovenzana, A; Spinelli, Antonello; Canciani, B; Brunelli, S; Ravazzolo, R; Bocciardi, R

Histological Evaluation and Management of Rare Case of Supernumerary &quot;Ghost&quot; Teeth

Supernumerary teeth are teeth that exceed the normal dental formula. Their prevalence in the permanent dentition is 1-14% and they occur more frequently in maxilla with a sex ratio of 2: 1 in favor of males. They are often associated with syndromes but there are examples of nonsyndromic multiple supernumerary teeth reported in the literature. CBCT is usually the best exam for radiographic diagnosis and treatment planning, because it provides 3D information about location and morphology of supernumerary teeth. This paper reports a rare case of four supernumerary teeth in a nonsyndromic 9-year-old boy. The peculiarity of this case is that two more exceeding teeth were found during surgical procedure. After extraction, all the teeth underwent a histological undecalcified processing for light microscopical examination. The two "ghost" supernumerary teeth seemed to be primordial dental germs, possibly resulting from an altered odontogenic process. After supernumerary teeth extraction, X-rays and exfoliation monitoring are recommended, since permanent retained teeth often erupt naturally or, at least, improve their condition. Radiographic follow-up is also useful in order to assess the formation of further teeth due to the hyperactivity of the dental lamina