Periostin in the relation between periodontal disease and atherosclerotic coronary artery disease: A pilot randomized clinical study.

OBJECTIVE: The aim of this study was to analyze the effects of periodontal treatment on markers of atherosclerotic coronary artery disease and circulating levels of periostin. BACKGROUND: Periostin is necessary for periodontal stability, but it is highly present in atherosclerotic plaques. Treatment of periodontal disease, with low levels of local periostin, is thought to reduce systemic levels of periostin. Thus, this may contribute to cardiovascular health. METHODS: A pilot randomized controlled clinical trial was designed to include patients with severe periodontal disease and history of atherosclerotic coronary artery disease. Samples of gingival crevicular fluid (GCF) and serum were collected before and after periodontal treatment by periodontal surgery or non-surgical therapy. The levels of several markers of inflammation and cardiovascular damage were evaluated including CRP, IFN-γ, IL-1ß, IL-10, MIP-1α, periostin, and TNF-α in GCF and CRP, Fibrinogen, IFN-γ, IL-1ß, IL-6, IL-10, L-Selectin, MIP-1α, Periostin, TNF-α, and vWF in serum. RESULTS: A total of 22 patients with an average of 56 years old were recruited for participating in this study. Twenty of them were male. Most of them (82%) had suffered an acute myocardial event and underwent surgery for placing 1, 2, or 3 stents in the coronary arteries more than 6 months ago but less than 1 year. The treatment of periodontal disease resulted in an overall improvement of all periodontal parameters. Regarding the evaluation of GCF and serum, a significant increase of periostin in the GCF was observed after periodontal surgery. In contrast, although other markers in GCF and serum improved, no significant correlations were found. CONCLUSION: Treatment of periodontal disease through periodontal surgery induces a local and transient increase in the levels of periostin in the gingival crevicular fluid. The effects on systemic markers of inflammation and cardiovascular function have not been confirmed.

Correlation between Inflammasomes and Microbiota in Peri-Implantitis.

The activation of inflammasomes is thought to induce the inflammatory process around dental implants. No information is available on the correlation between microbiota and inflammasomes in clinical samples from patients suffering peri-implantitis. For this cross-sectional study, 30 biofilm samples were obtained from 19 patients undergoing surgical treatment for peri-implantitis because of the presence of bleeding on probing, probing depth higher than 6 mm, and radiographic bone loss higher than 3 mm. Then, soft tissue samples from around the implant were also collected. The relative abundance of bacteria and alpha-diversity indexes were calculated after analyzing the 16S rRNA gene using next-generation sequencing. The soft-tissue samples were processed for evaluation of the inflammasomes NLRP3 and AIM2 as well as caspase-1 and IL-1ß. The relative abundance (mean (SD)) of specific species indicated that the most abundant species were Porphyromonas gingivalis (10.95 (14.17)%), Fusobacterium vincentii (10.93 (13.18)%), Porphyromonas endodontalis (5.89 (7.23)%), Prevotella oris (3.88 (4.94)%), Treponema denticola (2.91 (3.19)%), and Tannerella forsythia (2.84 (4.15)%). Several correlations were found between the species and the immunohistochemical detection of the inflammasomes NLRP3 and AIM2 as well as caspase-1 and IL-1ß, both in the epithelium and the lamina propria. A network analysis found an important cluster of variables formed by NLRP3 in the lamina propria and AIM2, caspase-1, and IL-1ß in the lamina propria and the epithelium with Prevotella dentalis, Prevotella tannerae, Tannerella forsythia, or Selenomonas timonae. Thus, it could be concluded that inflammasomes NLRP3 and AIM2 and their downstream effectors caspase-1 and interleukin-1ß can be significantly associated with specific bacteria.

Inflammasomes NLRP3 and AIM2 in peri-implantitis: A cross-sectional study.

BACKGROUND: Inflammasome components NLRP3 and AIM2 contribute to inflammation development by the activation of caspase-1 and IL-1ß. They have not been yet evaluated in samples from patients with active peri-implantitis. Thus, the aim of the present study is to analyze the expression of inflammasomes NLRP3 and AIM2 and subsequent caspase 1 and IL-1ß assessing the microenvironment of leukocyte subsets in samples from patients with active peri-implantitis. METHODS: Biopsies were collected from 33 implants in 21 patients being treated for peri-implantitis. Biopsies from gingival tissues from 15 patients with healthy periodontium were also collected for control. These tissues were evaluated through conventional histological stainings. Then, immunohistochemical detection was performed to analyze NLRP3, AIM2, caspase-1, and IL-1ß and markers of different leukocyte subsets. PCR for inflammasomes and related genes was also done. RESULTS: This manuscript reveals a high immunohistochemical and mRNA expression of NLRP3 and AIM2 inflammasomes, caspase-1, and IL-1ß in biopsies collected from human peri-implantitis. The expression of the tested markers was significantly correlated with the increase in inflammatory infiltrate, probing depth, presence of biofilm, and bleeding on probing. In these peri-implantitis lesions, the area of biopsy tissue occupied by inflammatory infiltrate was intense while the area occupied by collagen was significantly lower. In comparison with periodontal healthy tissues, the inflammatory infiltrate was statistically significantly higher in the peri-implantitis biopsies and was mainly composed of plasma cells, followed by T and B lymphocytes. CONCLUSION: In human peri-implantitis, chronic inflammation can be explained in part by the action of IL-1ß/caspase 1 induced through NLRP3 and AIM2 inflammasome activation.

Limited marginal bone loss in implant-supported fixed full-arch rehabilitations after 5 years of follow-up.

PURPOSE: The aim of the present study was to evaluate the 5-year results in terms of marginal bone level (MBL) around implants supporting fixed full-arch metal-ceramic restorations in a series of cases of patients who had lost their teeth in that dental arch because of severe periodontal disease. MATERIAL AND METHODS: A retrospective cohort study was designed to evaluate the 5-year MBL results of OsseoSpeed™ Astra Tech TX implants with internal tapered conical connection. Age, gender, bone substratum, smoking habits, history of periodontitis, and prosthetic features were recorded. Mixed linear model was used to determine the influence of the different variables on MBL. RESULTS: In this series, a total of 160 implants placed in 19 patients were evaluated. No implant failure was reported during the 5 years of follow-up. Only 14 (8.75%) implants had more than 2 mm of MBL. Abutment height, F(3,142) = 6.917, p < .001, and implant diameter, F(1,141) = 15.059, p < .001, were determined to be statistically associated with MBL. No other effect was significant. Pairwise comparisons showed that MBL was larger for abutment height = 1 (MBL = -0.987, SE = 0.186) compared with the remaining heights [-0.335 (0.171), -0.169 (0.192) and -0.247 (0.267), 2, 4 and 6 mm, respectively]. MBL was larger for narrow (-0.510, SE = 0.169) than for wide implants (-0.364, SE = 0.190). CONCLUSION: The current study demonstrates that the vast majority of internal conical connection implants supporting fixed full-arch metal-ceramic restorations do not suffer from relevant MBL after 5 years in function. Particularly, those implants with transmucosal abutments longer than 2 mm show less than 0.5 mm from the implant shoulder to the marginal bone.

Maxillary sinus floor augmentation comparing bovine versus porcine bone xenografts mixed with autogenous bone graft. A split-mouth randomized controlled trial.

AIM: To compare the effectiveness of two xenografts for maxillary sinus floor augmentation in terms of clinical, radiographical, histologic, and molecular outcomes. MATERIALS AND METHODS: A split-mouth randomized clinical trial was conducted at the University of Granada. Ten consecutive patients in need of bilateral two-staged maxillary sinus floor augmentation were included. Each patient received both biomaterials (porcine bone mineral and anorganic bovine bone), which were randomly assigned for bilateral sinus augmentation. The maxillary autogenous bone scraped from the sinus access window was mixed with each xenograft at a 20:80 ratio. After a healing period of 6 months, bone biopsies were collected with a trephine during the implant placement in the regenerated area. Histologic, histomorphometrical, immunohistochemical, and molecular outcomes were analyzed. Clinical and radiographical data throughout the treatment phases were also evaluated. RESULTS: The resulting anatomic features were similar between both groups. After six months of graft consolidation, the graft resorption rates were similar between both biomaterials. The histologic, histomorphometrical, and immunohistochemical results showed no statistical differences between groups. CONCLUSION: Anorganic bovine bone and porcine bone mineral combined with maxillary autogenous cortical bone show similar biologic and radiologic features in terms of biomaterial resorption, osteoconduction, and osteogenesis when used for maxillary sinus floor augmentation.

The impact of tooth loss on cognitive function.

OBJECTIVE: To investigate if there is epidemiological evidence of an association between edentulism and cognitive decline beside that currently available from limited sample-sized case series and cross-sectional studies considering limited co-variables. MATERIALS AND METHODS: Data from two USA national health surveys [NHIS 2014-2017 and NHANES 2005-2018] were analyzed using multinomial logistic regression to study the impact of type of edentulism and number of remaining teeth on memory and concentration problems. Age, gender, socioeconomic status, education level, cardiovascular health index, body mass index, exercise, alcohol, smoking habits, and anxiety and depression were used as covariates. RESULTS: The combined population sample was 102,291 individuals. Age, socioeconomic status, educational level, anxiety and depression levels, and edentulism showed the highest odds ratios for cognitive decline. Number of teeth present in the mouth was found to be a predictor of cognitive status. This association showed a gradient effect, so that the lower the number of teeth, the greater the risk of exhibiting cognitive decline. CONCLUSIONS: Edentulism was found among the higher ORs for cognitive impairment. CLINICAL RELEVANCE: Maintenance of functional teeth through the promotion of oral health may contribute to the preservation of memory/concentration and other essential cognitive functions. Thus, increasing and efficiently coordinating efforts aimed at preventing of tooth loss in the adult population could substantially contribute to reduce the incidence of cognitive impairment.

Oral health and healthy chewing for healthy cognitive ageing: A comprehensive narrative review.

INTRODUCTION: Ageing leads to physiological cognitive decline that it is worsened in people with neurodegenerative diseases such as Alzheimer's disease. Despite the ongoing search for a solution to this cognitive decline, no effective remedies have been established. It has been determined that modifiable external factors, such as oral health and occlusal function, prevent cognitive decline. OBJECTIVE: To analyse the primary interactions between occlusal function and cognitive functions. MAIN FINDINGS: Masticatory function is related to cognitive functions. In particular, current evidence, from both animal and human studies, suggests that the activation of masticatory muscles and proper mastication, with natural teeth or dental prosthesis, induces the release of several mediators and the activation of specific brain areas. Together, they result in higher neuronal activity, neurotrophic support, blood flow and the prevention of amyloid-beta plaque formation. Thus, all the components of the masticatory system must work together in order to preserve cognitive function. CONCLUSIONS: Available evidence suggests that oral and cognitive health are more interconnected than previously thought. Therefore, maintenance and adequate restoration of the whole masticatory system are important for the prevention of cognitive decline. In summary, oral and chewing health lead to healthy cognitive ageing.

Algae-derived hydroxyapatite behavior as bone biomaterial in comparison with anorganic bovine bone: A split-mouth clinical, radiological, and histologic randomized study in humans.

OBJECTIVES: To analyze a modified biphasic phycogenic biomaterial in comparison with anorganic bovine bone in maxillary sinus floor elevation in humans. MATERIAL AND METHODS: Eight male patients in need of bilateral two-stage sinus floor elevation were consecutively recruited for this randomized split-mouth study. A combination of autogenous cortical bone (ACB, 20%) and anorganic bovine bone (ABB, 80%) (ACB + ABB group) or ACB (20%) and modified biphasic phycogenic material (BP, 80%) (ACB + BP group) were randomly assigned to graft each sinus. Patients were followed up for 6 months post-surgery when bone samples were collected for analysis. RESULTS: Radiographically, bone height gain was statistically higher in the ACB + ABB versus the ACB + BP group. While the analysis of the biological compartments showed differences in non-mineralized tissue (39.15 ± 20.97% vs. 65.87 ± 28.59%, ACB + ABB vs. ACB + BP respectively; p = .018) and remnant biomaterial particles (22.62 ± 17.01% vs. 7.96 ± 8.57%, respectively; p = .028), the percentage of mineralized tissue (38.23 ± 17.55% vs. 24.14 ± 24.66%, respectively; p = .398) showed no statistically significant difference. In contrast, ACB + ABB biopsies showed higher Musashi-1-positive cells per mm2 compared to ACB + BP biopsies (811.49 ± 875.30 vs. 236.90 ± 280.81; p < .018), where the fusiform cells corresponded mainly with fibroblasts, as demonstrated by ultrastructural analysis. CONCLUSION: Both combinations of materials exhibited bone formation after 6 months of healing in the maxillary sinus cavity. However, the combination with biphasic phycogenic biomaterial induced a higher radiographical vertical resorption and graft collapse in comparison with the combination with anorganic bovine bone, possibly due to a higher remodeling of the graft.

Characterization and comparison of neutrophil extracellular traps in gingival samples of periodontitis and gingivitis: A pilot study.

BACKGROUND AND OBJECTIVE: Neutrophil extracellular traps (NETs) are a recently discovered antimicrobial mechanism used by neutrophils that have been proposed as an intervention in the pathogenesis of periodontitis. The objective of our study was to characterize the expression of NETs in gingival tissues with periodontitis and controls and to compare the expression of these traps in gingival tissue samples of patients with gingivitis and periodontitis. MATERIAL AND METHODS: An observational cross-sectional study was conducted on patients with periodontitis, gingivitis, and controls that needed tooth extraction. Gingival tissue biopsies were gathered after clinical examination and tooth extraction. Electron microscopy and immunofluorescence were performed to characterize NETs, comparing periodontitis and control patients. Immunohistochemical analysis was performed to quantify neutrophil extracellular trap expression through extracellular citrullinated histone H3 and myeloperoxidase in biopsies from patients with gingivitis and periodontitis. RESULTS: Thirteen biopsies were gathered from 13 patients: five gingivitis, six periodontitis, and two controls. Electron microscopy and immunofluorescence imaging showed greater expression of neutrophils present in periodontal inflamed tissue compared with controls. Release of nuclear content to the extracellular space was observed, compatible with the formation of NETs. The expression of citrullinated histone H3 was higher in gingivitis samples than periodontitis samples (P = 0.0106). Myeloperoxidase expression was higher in periodontitis than gingivitis, but without achieving statistical significance. CONCLUSION: Neutrophil extracellular traps were found in tissue samples of periodontitis as extracellular components of chromatin, along with neutrophil enzymes, that were not present in healthy controls. The comparison of NETs expression in periodontitis and gingivitis showed higher expression in gingivitis, associating them to acute phases of the periodontal inflammatory process.

Biphasic hydroxyapatite and ß-tricalcium phosphate biomaterial behavior in a case series of maxillary sinus augmentation in humans.

OBJECTIVES: The aim of this study was to evaluate and compare the morphometric components and the histological properties of pristine bone and bone grafted with a biphasic ß-tricalcium phosphate in humans using the maxillary sinus model. Reparative mesenchymal stem cells in the pristine bone and graft were also evaluated. MATERIALS AND METHODS: For this prospective case series, sinus augmentation was performed using a biphasic ß-tricalcium phosphate. After 6 months of healing, a core of remnant native alveolar bone and grafted bone was collected with a trephine. Histological, histomorphometrical, and immunohistochemical techniques were performed. Radiological analysis through cone beam computerized tomography was also conducted. RESULTS: A total of 10 patients were enrolled in this study. Radiologically, patients showed an average increase of crestal bone of 8.03 ± 1.72 mm. Morphologically, the grafted area was composed by 34.93 ± 14.68% of new mineralized tissue, 9.82 ± 11.42% of remnant biomaterial particles, and 55.23 ± 11.03% non-mineralized tissue. Histologically, we found no differences in the number of osteocytes per mm2 (p = 0.674), osteoblasts (p = 0.893), and blood vessels (p = 0.894) in the grafted area compared to the pristine bone. Differences were found on the number of osteoclasts (15.57 ± 27.50 vs. 5.37 ± 16.12, p = 0.027). The number of Musashi-1 positive mesenchymal cells (239.61 ± 177.4 vs. 42.11 ± 52.82, p = 0.027) was also significantly higher in the grafted area than in the pristine bone. CONCLUSION: Biphasic ß-tricalcium phosphate is a suitable biomaterial to be used in the formation of new bone in sinus floor elevation procedures in humans, not only from the histomorphometrical point of view, but also regarding the cellular and vascular quality of the regenerated bone.

Expression of Musashi-1 During Osteogenic Differentiation of Oral MSC: An In Vitro Study.

BACKGROUND: Musashi-1 (MSI1) is a negative regulator of mesenchymal stromal cell (MSC) differentiation which in turn favors cell proliferation. However, little is known about its expression by MSC from the oral cavity and in the context of osteogenic differentiation. AIM: The aim of this study was to analyze the expression of MSI1 in the context of osteogenic differentiation of MSC derived from the oral cavity. MATERIAL/METHODS: For this in vitro study, MSC were isolated from six different origins of the oral cavity. They were extensively characterized in terms of proliferative and clonogenicity potential, expression of stemness genes (MYC, NANOG, POU5F1, and SOX2), expression of surface markers (CD73, CD90, CD105, CD14, CD31, CD34, and CD45) and adipo-, chondro- and osteogenic differentiation potential. Then, osteogenic differentiation was induced and the expression of MSI1 mRNA and other relevant markers of osteogenic differentiation, including RUNX2 and Periostin, were also evaluated. RESULTS: Cell populations from the alveolar bone (pristine or previously grafted with xenograft), dental follicle, dental germ, dental pulp, and periodontal ligament were obtained. The analysis of proliferative and clonogenicity potential, expression of the stemness genes, expression of surface markers, and differentiation potential showed similar characteristics to those of previously published MSC from the umbilical cord. Under osteogenic differentiation conditions, all MSC populations formed calcium deposits and expressed higher SPARC. Over time, the expression of MSI1 followed different patterns for the different MSC populations. It was not significantly different than the expression of RUNX2. In contrast, the expression of MSI1 and POSTN and RUNX2 were statistically different in most MSC populations. CONCLUSION: In the current study, a similar expression pattern of MSI1 and RUNX2 during in vitro osteogenic differentiation was identified.

Histopathological comparison of healing after maxillary sinus augmentation using xenograft mixed with autogenous bone versus allograft mixed with autogenous bone.

OBJECTIVE: To compare the clinical and histologic outcomes of two different grafting materials (allograft and xenograft) when combined with autogenous bone and covered with a collagen membrane for sinus augmentation. MATERIAL AND METHODS: A parallel case series of fourteen patients in need of a unilateral sinus augmentation was evaluated in this study. Seven patients received a graft composed by autologous cortical bone (ACB) and anorganic bovine bone in a ratio of 1:1; the other seven patients received ACB mixed with an allograft in the same ratio. Bone biopsies were obtained 6 months after sinus augmentation at the time of implant placement. Comparative histomorphometrical, histopathological, and immunohistochemical analyses were conducted and statistically analyzed. RESULTS: After 12 months of functional loading, all implants in both groups were clinical and radiographically successful. Histomorphometrically, although the initial bone formation was not significantly different between groups (new mineralized tissue: 41.03(12.87)% vs. 34.50(13.18)%, p = .620; allograft vs. xenograft groups), the graft resorbed faster in the allograft group (remnant graft particles: 9.83[7.77]% vs. 21.71[17.88]%; p = .026; allograft vs. xenograft groups). Non-mineralized tissue did not statistically differ either (49.00[14.32]% vs. 43.79[19.90]%; p = .710; allograft vs. xenograft groups). The histologic analyses revealed higher cellular content, four times more osteoid lines, and higher vascularization in the xenograft group. Musashi-1 (mesenchymal stromal cell marker) was also more intensively expressed in the xenograft group (p = .019). CONCLUSIONS: Both composite grafts generate adequate substratum to receive dental implants after healing. Compared with the xenograft composite, allograft composite shows faster turnover and a quicker decrease in biological action after 6 months.

Abutment height influences the effect of platform switching on peri-implant marginal bone loss.

PURPOSE: The purpose was to radiographically analyze and compare the marginal bone loss (MBL) between implants with different mismatching distance and to study the influence of the prosthetic abutment height on the MBL in association with the related mismatching distances. MATERIAL AND METHODS: This retrospective study included 108 patients in whom 228 implants were placed, 180 with diameter of 4.5 mm and 48 with diameter of 5 mm. All patients received OsseoSpeed™ implants with internal tapered conical connection (Denstply Implants). Different mismatching distances were obtained, given that all implants were loaded with the same uni-abutment type (Lilac; Denstply Implants). Data were gathered on age, gender, bone substratum, smoking habits, previous history of periodontitis, and prosthetic features. MBL was analyzed radiographically at 6 and 18 months post-loading. RESULTS: Mixed linear analysis of mesial and distal MBL values yielded significant effects of abutment, implant diameter, follow-up period, bone substratum, smoking, and abutment × time interaction. MBL was greater at 18 vs. 6 months, for short vs. long abutments, for grafted vs. pristine bone, for a heavier smoking habit, and for implants with a diameter of 5.0 vs. 4.5 mm. CONCLUSION: Greater mismatching does not minimize the MBL; abutment height, smoking habit, and bone substratum may play a role in the MBL over the short- and medium term.

Relationship between periodontal parameters and plasma cytokine profiles in pregnant woman with preterm birth or low birth weight.

OBJECTIVES: The aim was to determine whether clinical periodontal parameters are associated with plasma anti- and/or pro-inflammatory cytokines in pregnant woman with preterm birth (PB) or low birth weight (LBW) neonates. MATERIALS AND METHODS: An observational case-control study was performed in 131 puerperal women: mothers of PB/LBW neonates (cases, n = 67) and mothers of full-term normal-weight neonates (controls, n = 64). Sociodemographic and periodontal data was gathered from all participants, and interleukin (IL)-1ß, IL-6, IL-8, IL-10, IL-17, IL-23, and tumor necrosis factor alpha (TNF-α) were determined in plasma. RESULTS: In multiple linear regression models, clinical attachment loss was associated with TNF-α (0.28 ± 0.14; 95% confidence interval (CI) [0.006, 0.553]) and IL-1ß (0.43 ± 0.21; 95%CI [0.018, 0.842]), independent of group membership. IL-1ß (-1.67 ± 0.27, 95%CI [-2.199, -1.141]), IL-6 (-0.86 ± 0.27; 95%CI [-1.389, -0.331]), and IL-8 (-3.84 ± 0.50, 95%CI [-4.820, -2.860]) were lower, and IL-10 (0.86 ± 0.26; 95%CI [0.350, 1.370]) was higher in cases versus controls after adjusting for potential confounders. CONCLUSIONS: Clinical attachment loss was associated with plasma TNF-α and IL-1ß levels. No plasma cytokine profiles suggestive of systemic inflammatory response were observed in the pregnant women with PB/LBW neonates. CLINICAL RELEVANCE: Clinical attachment loss, as the main periodontal measure, is associated with TNF-α and IL-1ß plasma levels in pregnant women. No relationship was found between PB/LBW and the markers of systemic inflammatory response assessed in this study.

Marginal bone loss as success criterion in implant dentistry: beyond 2 mm.

AIM: The aim of this study was to analyze marginal bone loss (MBL) rates around implants to establish the difference between physiological bone loss and bone loss due to peri-implantitis. MATERIALS AND METHODS: Five hundred and eight implants were placed in the posterior maxilla in 208 patients. Data were gathered on age, gender, bone substratum (grafted or pristine), prosthetic connection, smoking and alcohol habits, and previous periodontitis. MBL was radiographically analyzed in three time frames (5 months post-surgery and at 6 and 18 months post-loading). Nonparametric receiver operating curve (ROC) analysis and mixed linear model analysis were used to determine whether implants could be classified as high or low bone loser type (BLT) and to establish the influence of this factor on MBL rates. RESULTS: Marginal bone loss rates were significantly affected by BLT, connection type, bone substratum, and smoking. Bone loss rates at 18 months were associated with initial bone loss rates: 96% of implants with an MBL of >2 mm at 18 months had lost 0.44 mm or more at 6 months post-loading. CONCLUSION: Implants with increased MBL rates at early stages (healing and immediate post-loading periods) are likely to reach MBL values that compromise their final outcome. Initial (healing, immediate post-loading) MBL rates around an implant of more than 0.44 mm/year are an indication of peri-implant bone loss progression.

Tobacco consumption induces alveolar crest height loss independently of mandibular bone mass and bone density.

AIM: To investigate the relationship of tobacco consumption with alveolar crest height (ACH) loss and mandibular bone mass estimated by digital panoramic radiography and cone-beam computed tomography (CBCT). MATERIAL AND METHODS: We studied 315 patients (43.2% [n = 136] men and 56.8% [n = 179] women) with mean age of 36.6 ± 5.3 (range 21-30 years (16.2%), range 31-46 years (83.8%); 9% (n = 71) were smokers (>10 cig./day). A mean of 13.0 ± 2.0 mandibular teeth were present: 37.5% of patients had 6-12 teeth and 62.5% 13-16 teeth. We analyzed 315 digital panoramic radiographs (2D) and calculated the ACH, mandibular cortical width, and basal and alveolar bone gray level values. ACH and bone density were also measured on CBCT (3D) in the 110 patients scheduled for implantation. RESULTS: In the univariate analysis, ACH loss was greater in older patients (P = 0.012) and in those with fewer mandibular teeth (P < 0.001) and showed a relationship with tobacco consumption that was close to significant (P = 0.079). In the multivariate analysis, the number of mandibular teeth (P < 0.001) and tobacco consumption (P = 0.048) were significantly associated with ACH. Alveolar and basal bone densities were associated, respectively, with number of mandibular teeth (P = 0.012) and cortical width (P = 0.030). CONCLUSION: In a Caucasian population aged 21-46 years, tobacco consumption was significantly associated with ACH loss. However, ACH loss showed no significant relationship with mandibular bone mass estimated either as mandibular cortical width index or bone density on digital panoramic radiographs or as bone density on CBCT. ACH loss was a local event independent of mandibular bone mass status.

Morphological evidences of Bio-Oss® colonization by CD44-positive cells.

OBJECTIVES: Our objectives were to examine vascular and cellular colonization in anorganic bovine bone (ABB) after 6 months of healing in human maxillary sinus augmentation grafts. MATERIAL AND METHODS: Fifty unilateral maxillary sinus augmentation procedures were performed on 50 consecutive patients. Bone cores were obtained through the implant receptor sites 6 months later and evaluated with morphological image analysis and immunohistochemical techniques. RESULTS: Image analysis revealed a mean of 35.44 ± 16% vital bone, 31.66 ± 15% non-mineralized tissue, and 32.72 ± 25% remnant ABB particles. In our patients, neovascularization in 46.3% of cases was demonstrated within ABB particles 6 months after sinus floor augmentation surgery. Neovascularization of ABB particles was inversely related to age, directly to osteoclast number per mm², and not influenced by habits or disease. CD44-positive cells colonization was found in 74% of cases. An important correlation was found regarding CD44 expression and number of vessel in ABB particles (r = 0.624 P < 0.001, Pearson). Osteopontin expression was detected on the interstitial boundary of bone with ABB particles and within the osteocyte lacunae and bone canaliculi and was relationship with presence of CD44-positive cells inside ABB particles (r = 0.388, P = 0.046, Pearson). CONCLUSION: In conclusion, images compatible with osteone colonized by osteocytes CD44 positive and neovascularization in ABB particles were observed after 6 months of graft maturation. These biologic events have not previously been morphologically and immunohistochemically documented.

Detection and comparison of neutrophil extracellular traps in tissue samples of peri-implantitis, periodontitis, and healthy patients: A pilot study.

OBJECTIVE: The aim of this study was to detect and compare the tissular expression of neutrophil extracellular traps (NETs) in peri-implant and periodontal samples of patients with peri-implantitis, periodontitis, and controls. MATERIALS AND METHODS: An observational study was performed on patients with peri-implantitis, periodontitis, and controls. Peri-implant and/or periodontal clinical examinations were performed on each participant. Tissue samples were collected during tooth/implant extraction for clinical reasons. Electron microscopy analysis, Picro-Sirius red staining, immunohistochemical (CD15), and immunofluorescence (citrullinated H3 and myeloperoxidase) techniques were performed to detect NET-related structures and the degree of connective tissue destruction, between the study groups. RESULTS: Sixty-four patients were included in the study: 28 peri-implantitis, 26 periodontitis, and 10 controls, with a total of 51 implants, 26 periodontal teeth, and 10 control teeth. Neutrophil release of nuclear content was observed in transmission electron microscopy. Immunohistochemical analysis showed a greater CD15 expression in both peri-implantitis and periodontitis compared to controls (p < 0.001), and peri-implantitis presented lower levels of connective tissue and collagen compared to both periodontitis (p = 0.044; p < 0.001) and controls (p < 0.001). Immunofluorescence showed greater citH3 expression in peri-implantitis than the one found in both periodontitis (p = 0.003) and controls (p = 0.048). CONCLUSIONS: A greater presence and involvement of neutrophils, as well as a greater connective tissue destruction were observed in cases of peri-implantitis. A higher expression of NET-related markers was found in mucosal samples of peri-implantitis compared to periodontitis and controls.

NLRP3 and AIM2 inflammasomes expression is modified by LPS and titanium ions increasing the release of active IL-1ß in alveolar bone-derived MSCs.

Periodontitis and peri-implantitis are inflammatory diseases of infectious etiology that lead to the destruction of the supporting tissues located around teeth or implants. Although both pathologies share several characteristics, it is also known that they show important differences which could be due to the release of particles and metal ions from the implant surface. The activation of the inflammasome pathway is one of the main triggers of the inflammatory process. The inflammatory process in patients who suffer periodontitis or peri-implantitis has been mainly studied on cells of the immune system; however, it is also important to consider other cell types with high relevance in the regulation of the inflammatory response. In that context, mesenchymal stromal cells (MSCs) play an essential role in the regulation of inflammation due to their ability to modulate the immune response. This study shows that the induction of NLRP3 and absent in melanoma 2 (AIM2) inflammasome pathways mediated by bacterial components increases the secretion of active IL-1ß and the pyroptotic process on human alveolar bone-derived mesenchymal stromal cells (hABSCs). Interestingly, when bacterial components are combined with titanium ions, NLRP3 expression is further increased while AIM2 expression is reduced. Furthermore, decrease of NLRP3 or AIM2 expression in hABSCs partially reverses the negative effect observed on the progression of the inflammatory process as well as on cell survival. In summary, our data suggest that the progression of the inflammatory process in peri-implantitis could be more acute due to the combined action of organic and inorganic components.

The Influence of History of Severe Periodontitis on Estimated Long-Term Marginal Bone Loss around Implants Restored with Fixed Segmented Full-Arch Rehabilitation.

The aim of this study was to analyze the long-term marginal bone level (MBL) of implants supporting fixed full-arch restoration in patients who had previously lost their dentition due to severe periodontitis. This retrospective study included 35 patients in whom 342 implants with internal tapered conical connections were placed. MBL was analyzed radiographically over time and a long-term estimation of MBL was calculated. A mixed linear model with abutment height, graft, diameter and location (maxilla/mandible) as factors and gender, age, implant length and prosthetic variables as covariates was used to evaluate the influence on MBL. MBL in these patients showed an estimator of predictions at 4108 days after loading of -0.307 mm, SE = 0.042. Only 0.15% of implants were radiographically affected with MBL of 3 mm or more. The mixed linear model results showed a main effect of the type of opposing dentition, gender, implant diameter, and abutment height. Particularly, an abutment height of 1 mm had associated larger MBL than the remaining heights. Thus, it can be concluded that dental implants restored with fixed segmented full-arch rehabilitation in patients with a history of severe periodontal disease do not suffer important marginal bone loss if some specific factors are considered, mainly the use of long transmucosal abutments (≥2 mm).