The use of digital technologies in peri-implant soft tissue augmentation - A narrative review on planning, measurements, monitoring and aesthetics.

OBJECTIVE: To identify the different uses and modalities of digital technologies to diagnose, plan and monitor peri-implant soft tissue conditions and aesthetics. METHODS: A comprehensive narrative review of pertinent literature was conducted, critically appraising key digital technologies that may assist peri-implant soft tissue augmentation and assessment. An electronic search on four databases including studies published prior to 1st July 2023 was performed and supplemented by a manual search. RESULTS: Predominantly, tools such as cone beam computed tomography (CBCT), intraoral scanning (iOS), intraoral ultrasonography and digital spectrophotometry were commonly to assess and monitor peri-implant soft tissues. The main clinical and research applications included: (i) initial assessment of mucosal thickness, supra-crestal tissue height and keratinized mucosa width, (ii) evaluation of peri-implant soft tissue health and inflammation, (iii) monitoring profilometric changes and midfacial mucosal margin stability over time and (iv) aesthetic evaluation through colour assessment. While evidence for some digital tools may be limited, the integration of digital technologies into peri-implant soft tissue management holds great promise. These technologies offer improved precision, comfort and speed in assessment, benefiting both patients and clinicians. CONCLUSION: As digital technologies progress, their full potential in peri-implant soft tissue augmentation and their value will become more evident with ongoing research. Embracing these innovations and their potential benefits is recommended to ensure that during progress in implant dentistry, patient care is not hindered.

The distance of insertion points from wound margins in interrupted and vertical mattress sutures influences the tensile load capacity: An in vitro experimental study.

AIM: To determine the tensile load capacity (TLC) and the tearing characteristics for interrupted and vertical mattress sutures with different insertion points from the wound margin, and the effect of the bite size when using vertical mattress sutures. MATERIALS AND METHODS: A total of 120 gingiva and lining mucosa samples obtained from pig jaws were divided into groups according to the suturing technique (interrupted and vertical mattress sutures), distance of the insertion points from the wound margin (margin, 1, 3, and 5 mm) and bite size (1, 3, and 5 mm). The TLC of the suture and the tearing characteristics were evaluated using a tensile tester device. RESULTS: The TLC was significantly higher for vertical mattress sutures than for interrupted sutures regardless of the distance of the insertion points from the wound margin (intergroup p < .001). This distance significantly influenced the TLC for vertical mattress sutures (p < .05) but not for interrupted sutures (p > .05). Testing the tearing characteristics revealed that no tissue tearing occurred in groups when the insertion points were more than 3 mm from the wound margin. CONCLUSION: The TLC is higher for vertical mattress sutures than for interrupted sutures, and it increases when the insertion points are farther from the wound margin.

Immediate loading on two adjacent single dental implants with definitive nonsplinted restorations: A proof of concept in the posterior zone.

OBJECTIVES: To evaluate clinical, clinician- and patient-reported outcomes (PROs) of two adjacent single posterior implants immediately loaded with definitive single crowns up to 1 year. Ten patients in need of two adjacent posterior single implants were included. All implants were placed applying a fully digital workflow. Definitive screw-retained single zirconia crowns were delivered within 72 h after implant placement. Clinical parameters, patient- and clinician-reported outcomes were assessed up to 1 year of follow-up. CLINICAL CONSIDERATIONS: Clinical outcomes remained stable, with no implant failures or technical and biological complications throughout the observation period. Patient satisfaction was very high at baseline (crown delivery) and remained consistently high at 6 and 12 months of follow-up. Crown insertion 3 days after implant placement was rated as an easy procedure by clinicians. CONCLUSIONS: Two adjacent single implants with immediate definitive restorations (<72 h) in the posterior region appear to be a viable and easy treatment option to shorten the overall treatment time and potentially enhancing patient satisfaction. However, randomized controlled trials are needed to confirm the advantages of this treatment protocol over a delayed loading approach. CLINICAL SIGNIFICANCE: In selected cases, immediate implant loading with definitive restorations in the posterior region appears a valuable and straightforward option to shorten the overall treatment time.

Epidemiology of mid-buccal gingival recessions according to the 2018 Classification System in South America: Results from two population-based studies.

AIM: The aim of this investigation was to estimate the prevalence, severity and extent of mid-buccal gingival recessions (GRs; classified according to the 2018 Classification System) and to identify their risk indicators in the South American population. MATERIALS AND METHODS: Epidemiological data from two cross-sectional studies-performed on 1070 South American adolescents and 1456 Chilean adults-were obtained. All participants received a full-mouth periodontal examination by calibrated examiners. GR prevalence was defined as the presence of at least one mid-buccal GR ≥ 1 mm. GRs were also categorized into different recession types (RTs) according to the 2018 World Workshop Classification System. Analyses for RT risk indicators were also performed. All analyses were carried out at the participant level. RESULTS: The prevalence of mid-buccal GRs was 14.1% in South American adolescents and 90.9% in Chilean adults. In South American adolescents, the prevalence of RTs was 4.3% for RT1 GRs, 10.7% for RT2 GRs and 1.7% for RT3 GRs. In Chilean adults, the prevalence of RT1 GRs was 0.3%, while the prevalence of RT2 and RT3 GRs was 85.8% and 77.4%, respectively. Full-Mouth Bleeding Score (FMBS; <25%) was associated with the presence of RT1 GRs in adolescents. The risk indicators for RT2/RT3 GRs mainly overlapped with those for periodontitis. CONCLUSIONS: Mid-buccal GRs affected 14.1% of South American adolescents, whereas they affected most of the Chilean adult population (>90%). While RT1 GRs are more commonly observed in a non-representative cohort of South American adolescents (when compared to Chilean adults), the majority of Chilean adults exhibit RT2/RT3 GRs.

The L-shape technique in guided bone regeneration with simultaneous implant placement in the esthetic zone: A step-by-step protocol and a 2-14 year retrospective study.

OBJECTIVES: To describe the methodology of the "L-shape" technique in guided bone regeneration (GBR) with simultaneous implant placement and report on the clinical, esthetic, and patient satisfaction outcomes up to 14 years of follow-up. MATERIAL AND METHODS: Fourteen patients treated with the "L-shape" technique were included in this retrospective study. The L-shape technique was performed by trimming and placing a soft-type bone block made of deproteinized bovine bone mineral with 10% collagen at the buccal-occlusal aspect of the dental implant. The remaining gaps were filled with deproteinized bovine bone mineral granules and the augmented area was covered with a collagen membrane. The following parameters were recorded:  probing depth (PD), bleeding on probing (BOP), plaque index (PI), keratinized tissue width (KT) and marginal bone level (MBL). Esthetic outcomes were assessed according to the pink esthetic score (PES) and the white esthetic score (WES). Patient satisfaction was evaluated by means of a numerical rating scale (0-10). The stability of each augmented site was assessed by measuring the volumetric changes between baseline (crown delivery) and the respective follow-up. RESULTS: A total of 13 maxillary incisors and one maxillary canine in 14 patients were included. The mean follow-up period was 7.7 ± 3.8 years. PES values amounted to 10.7 ± 3.3 and WES to 8.8 ± 1.4. Patient satisfaction reached 9.4 ± 0.8. Mean PD at implant sites were 2.7 ± 0.7 mm while BOP amounted to 15.0 ± 0.2% and Pl to 5.0 ± 0.0%. Volumetric analyses revealed minimal changes at the augmented sites irrespective of the region of interest. Radiographic MBL remained relatively stable. CONCLUSIONS: Within the limitation of the present study the L-shape augmentation procedure seems to be a reliable technique when performing GBR with simultaneous implant placement in the esthetic zone. Outcomes encompassed stable clinical and esthetic results accompanied by high levels of patient satisfaction. Future randomized controlled trials are warranted to confirm possible benefits of the L-shape technique over traditional approaches. CLINICAL SIGNIFICANCE: The L-shape appears to be a simple yet promising technique in GBR with simultaneous implant placement that can easily be translated into clinical practice.

Effect of collagen membrane fixation on ridge volume stability and new bone formation following guided bone regeneration.

AIM: To test the effect of membrane fixation on ridge volume stability and new bone formation using guided bone regeneration. MATERIALS AND METHODS: In eight beagle dogs, after bilateral extraction of the maxillary pre-molars, a box-shaped defect was created on each side. All defect sites were augmented with a particulate bone substitute material, covered with either one of two non-cross-linked collagen membranes (CM1 or CM2) with or without fixation (-F or -UF). Samples were collected after 8 weeks. Histomorphometric and micro-computed tomography analyses were performed. RESULTS: Membrane fixation made no significant difference to the total augmented volume for both membranes (p > .05). Histological data indicated that at the ridge crest the augmented tissue width amounted to 2.4 ± 0.4 mm in the group CM1-F and 2.4 ± 0.5 mm in the group CM1-UF, with no significant difference between the groups. Conversely, in CM2-F the augmented tissue width was significantly larger than in CM2-UF (2.3 ± 0.1 vs. 1.57 ± 0.27, p < .05). CONCLUSIONS: Membrane fixation in contained defects failed to improve ridge volume stability regardless of the membrane type. However, it may enhance the width of the augmented ridge at the coronal portion depending on the type of membrane.

Membrane fixation enhances guided bone regeneration in standardized calvarial defects: A pre-clinical study.

AIM: To determine whether collagen membrane (CM) fixation enhances guided bone regeneration in standardized defects. MATERIALS AND METHODS: Four 8-mm-diameter defects were surgically made in eight rabbit calvaria, and randomly allocated into four groups: control (empty), unfixed-CM, fixed-CM, and unfixed-CM with bone graft (BG + CM) (positive control). After 1- and 4-week healing periods, the animals were sacrificed and quantitative reverse transcription polymerase chain reaction, micro-computed tomography, and histological outcomes were assessed. RESULTS: At week 1, the expression levels of BMP-2, FGF-2, VEGF, and osteocalcin were significantly higher in the fixed-CM group than in the unfixed-CM and control groups (p < .05). Conversely, cathepsin-K was significantly expressed in the unfixed-CM group. No significant differences in expression markers were observed between the fixed-CM and BG + CM groups (p > .05). At week 4, new bone formation was significantly higher in the fixed-CM group than the unfixed-CM and control groups (p < .05), but similar to the BG + CM group (p > .05). CONCLUSIONS: CM fixation enhances the expression of osteogenic factors similar to BG + CM, leading to significantly more new bone formation. This suggests that the osteogenic potential is greater when membranes are fixed, thereby limiting the necessity of membrane-supporting materials to enhance bone formation.

Caspase inhibitor attenuates the shape changes in the alveolar ridge following tooth extraction: A pilot study in rats.

OBJECTIVE: The aim of the study was to determine whether the inhibition of apoptosis via pan-caspase inhibitors can attenuate the changes in the alveolar ridge upon tooth extraction. BACKGROUND: Cells undergoing apoptosis might play a central role in the onset of alveolar bone resorption and the ensuing bone atrophy following tooth extraction. Caspases are proteases that regulate apoptotic cell death. It is, therefore, reasonable to hypothesize that blocking apoptosis with pan-caspase inhibitors attenuates the changes in the alveolar ridge following tooth extraction. METHODS: In 16 inbred rats, the mandibular first (M1) and second (M2) molars of one side were extracted. Following random allocation, the rats received either a cell-permeable pan-caspase inhibitor or diluent. After a healing period of 10 days, changes in shape and height of the alveolar ridge were examined using geometric morphometrics and linear measurements based on micro-computed tomography. RESULTS: Geometric morphometric analysis revealed that the pan-caspase inhibitor prevented major shape changes of the alveolar ridge following M1 tooth extraction (P < .05). Furthermore, linear measurements confirmed that the pan-caspase inhibitor significantly prevented the atrophy of the alveolar ridge height following M1 tooth extraction compared to the diluent controls (-0.53 mm vs -0.24 mm; P = .012). M2 tooth extraction caused no shape changes of the alveolar ridge, and thus, the pan-caspase inhibitor group did not differ from the control group (-0.14 mm vs -0.05 mm; P = .931). CONCLUSIONS: These findings suggest that the inhibition of apoptosis may attenuate shape changes of the alveolar ridge following M1 tooth extraction in rodents.

Two short implants versus one short implant with a cantilever: 5-Year results of a randomized clinical trial.

AIM: To test whether or not the use of a short implant with a cantilever results in similar clinical and radiographic outcomes compared to two adjacent short implants with single tooth reconstructions. MATERIALS AND METHODS: Thirty-six patients with two adjacent missing teeth in the posterior region were randomly assigned to receive either a single 6-mm implant with a cantilever (ONE-C) or two 6-mm implants (TWO). Fixed reconstructions were inserted 3-6 months after implant placement and patients were re-examined up to 5 years (FU-5). RESULTS: A total of 26 patients were available for re-examination at FU-5. The survival rate amounted to 84.2% in ONE-C and to 80.4% in TWO (inter-group: p = .894). Technical complication rates amounted to 64.2% (ONE-C) and to 54.4% (TWO) (inter-group: p = 1.000). From baseline to FU-5, the median changes of the marginal bone levels were 0.13 mm in ONE-C and 0.05 mm in TWO (inter-group: p = .775). Probing depth, bleeding on probing, and plaque control record values showed no significant differences between the two treatment modalities (p > .05). CONCLUSIONS: Short implants with a cantilever render similar clinical and radiographic outcomes compared to two adjacent short implants at 5 years, however, they tend to fail at earlier time points suggesting an overload of the implants. Considering the modest survival rates, the clinical indication of either treatment option needs to be carefully evaluated. ClinicalTrials.gov (NCT01649531).

Short communication: Cemented implant reconstructions are associated with less marginal bone loss than screw-retained reconstructions at 3 and 5 years of loading.

OBJECTIVES: To analyse whether there is a difference in marginal bone levels (MBL) and the respective changes between cemented and screw-retained reconstructions at 3 and 5 years of loading. METHODS: Radiographic data from 14 prospective multicentre clinical trials following implant loading with fixed cemented (CEM) or screw-retained (SCREW) reconstructions with a 3- to 5-year follow-up were retrieved from a database. MBL and MBL changes were assessed at initiation of implant loading (BL), at 3 (FU-3) and 5 years (FU-5) thereafter. The presence of peri-implantitis was also determined. RESULTS: Data from 1,672 implants at BL, 1,565 implants at FU-3 and 1,109 implants at FU-5 were available. The mean MBL amounted to 0.57 mm (SD 0.87) at BL, 0.55 mm (SD 0.86) at FU-3 and 0.65 mm (SD 1.18) at FU-5. At FU-3, the mean MBL was 0.44 mm (SD 0.65) in group CEM and 0.63 mm (SD 0.99) in group SCREW showing a significant difference between the groups (intergroup <0.05). At FU-5, the mean MBL was 0.42 mm (SD 0.77) in CEM and 0.80 mm (SD 1.37) in SCREW, again with significant differences between both groups (p < .05). MBL changes between BL and FU-3 amounted to 0.11 mm (SD 1.02) (bone loss) in SCREW and -0.17 mm (SD 1.03) (bone gain) in CEM. Similarly, mean MBL changes from BL to FU-5 amounted to 0.23 mm (SD 1.31) (bone loss) in SCREW and -0.26 mm (SD 1.27) (bone gain) in CEM. The prevalence of peri-implantitis amounted to 6.9% in CEM and 5.6% in group SCREW (intergroup p = .29063) at FU-3. At FU-5, peri-implantitis amounted to 4.6% in CEM and 6.2% in group SCREW (intergroup p = .28242). CONCLUSION: Cemented implant reconstructions compared with screw-retained reconstructions revealed higher marginal bone levels and similar rates of peri-implantitis during 5 years. The difference in MBL and the respective changes between the two groups, however, appear to be clinically negligible.

Clinical effects of probiotic or azithromycin as an adjunct to scaling and root planning in the treatment of stage III periodontitis: a pilot randomized controlled clinical trial.

BACKGROUND: The aim of this triple-blind placebo-controlled parallel-arm randomized clinical trial was to evaluate the clinical effects of Lactobacillus rhamnosus SP1 or azithromycin as an adjunct to scaling and root planing (SRP) in patients with stage III periodontitis. METHODS: Forty-seven systemically healthy participants with stage III periodontitis were recruited. Following SRP, the participants were randomly assigned to one of three treatment modalities; (1) placebo (n = 15), (2) probiotics (n = 16) and (3) antibiotics-azithromycin (n = 16). The participants were monitored at baseline, 3, 6, 9 and 12 months after therapy. Probing pocket depth (PPD), bleeding on probing (BOP), clinical attachment loss (CAL) and plaque accumulation (PI) were evaluated. RESULTS: All 47 participants completed the study. At 12 months, all groups showed significant improvements of PPD and PI (p < 0.012) irrespective of the treatment modality and without significant differences between the groups. Probiotics and azithromycin showed no added benefit in terms of CAL. While the placebo (p = 0.002) and the antibiotic-azithromycin (p = 0.002) group showed a significant reduction of BOP, only the placebo group revealed a significant reduction of CAL at 12 months follow-up (p = 0.003). The number of sites and teeth with PPD ≥ 5, ≥ 6 and ≥ 7 mm were significantly reduced in all groups at 12 months follow-up (p < 0.025) irrespective of the treatment regime and without significant differences between the groups. CONCLUSION: The use of probiotics or azithromycin as an adjunct to SRP failed to provide additional benefits in the treatment of stage III periodontitis. The benefits of these two treatment regimes as an adjunct to SRP remain unclear. TRIAL REGISTRATION: NCT02839408, 10/28/2017, Clinicaltrial.gov.

DBBM shows no signs of resorption under inflammatory conditions. An experimental study in the mouse calvaria.

OBJECTIVES: Deproteinized bovine bone mineral (DBBM) is not resorbable. However, the behavior of DBBM under inflammatory conditions remains unclear. Aim of the study was therefore to evaluate the resorption of DBBM under local inflammatory conditions in vivo using the calvarial osteolysis model. METHODS: In thirty adult BALB/c mice, DBBM was implanted into the space between the elevated soft tissue and the calvarial bone. Inflammation was induced either by lipopolysaccharides (LPS) injection or by polyethylene particles (Ceridust) mixed with DBBM. Three modalities were randomly applied (n = 10 each): (a) DBBM alone (control), (b) DBBM + LPS, and (c) DBBM + polyethylene particles (Ceridust). Mice were euthanized on day fourteen, and each calvarium was subjected to histological and µCT analysis. Primary outcome was the size distribution of the DBBM particles. Secondary outcome was the surface erosion of the calvarial bone. RESULTS: Histological and µCT analysis revealed that the size distribution and the volume of DBBM particles in the augmented site were similar between DBBM alone and the combinations with LPS or polyethylene particles. Moreover, histological evaluation showed no signs of erosions of DBBM particles under inflammatory conditions. µCT analysis and histology further revealed that LPS and the polyethylene particles, but not the DBBM alone, caused severe erosions of the calvarial bone as indicated by large voids representing the massive compensatory new immature woven bone formation on the endosteal surface. CONCLUSIONS: Local calvarial bone but not the DBBM particles undergo severe resorption and subsequent new bone formation under inflammatory conditions in a mouse model.

Efficacy of growth factors for the treatment of peri-implant diseases: a systematic review and meta-analysis.

OBJECTIVES: The aim of this study was to conduct a systematic review and meta-analysis on the efficacy of growth factors (GF) on clinical outcomes after treatment (surgical/non-surgical) of peri-implant diseases (peri-implant mucositis and peri-implantitis). MATERIALS AND METHODS: A protocol was developed to answer the following focused question: Is there any difference for the use of GF for treatment of peri-implant diseases versus comparative GF treatment or without GF? Electronic database and manual searches were independently conducted to identify randomized controlled trials (RCTs). Publications were selected based on eligibility criteria and then assessed for risk-of-bias using the Cochrane Handbook. The primary outcome was probing depth (PD) and bleeding on probing (BOP) reduction along with changes in vertical defect depth (VDD). Changes in clinical attachment level, gingival recession, and plaque index, among others, were studied as secondary outcomes. Based on primary outcomes, random-effects meta-analysis was conducted. RESULTS: A total of five RCTs were included. GF enhance the reduction of PD (standardized mean difference (SMD) = - 1.28; 95% confidence interval (CI) - 1.75, - 0.79; p = < 0.0001) and BOP (SMD = - 1.23; 95% CI - 1.70, - 0.76; p = < 0.0001) in the management of peri-implant mucositis. For the treatment of peri-implantitis, the use of GF yielded to significantly greater improvement in VDD (SMD = 0.68; 95% CI 0.22, 1.14; p = 0.004); however, there were no significant differences in terms of PD (SMD = 0.08; 95% CI - 1.08, 1.26; p = 0.887) and BOP (SMD = 0.211; 95% CI - 0.20, 0.63; p = 0.317). The overall risk of bias of the included studies was low to unclear. CONCLUSION: The results of the present systematic review suggest that the addition of GF might enhance the outcomes in the treatment of peri-implant mucositis. However, there is a lack of evidence for supporting additional benefit of GF managing peri-implantitis. CLINICAL RELEVANCE: Within the limitations of the current systematic review and based on the meta-analyses, (1) the addition of GF for the treatment peri-implant mucositis might be associated with better outcomes in terms of PD and BOP, and (2) an additional benefit of GF for the treatment peri-implantitis could not be determined on the basis of the selected evidence.

Effect of platelet-rich fibrin on cell proliferation, migration, differentiation, inflammation, and osteoclastogenesis: a systematic review of in vitro studies.

OBJECTIVE: To systematically assess the effects of platelet-rich fibrin (PRF) on in vitro cellular behavior. METHODS: A systematic electronic search using MEDLINE database was performed. In vitro studies using PRF were considered and articles published up to June 31, 2018 were screened. Eligible studies were selected based on the use of human PRF. RESULTS: In total, 1746 titles were identified with the search terms, from these 37 met the inclusion criteria and were chosen for data extraction. In addition, 16 new studies, mainly published in 2019, were also included in the analysis resulting in 53 studies. No meta-analysis could be performed due to the heterogeneity of study designs. Included studies show that PRF enhances proliferation, migration, adhesion, and osteogenic differentiation on a variety of cell types along with cell signaling activation. Furthermore, PRF reduces inflammation, suppresses osteoclastogenesis, and increases the expression of various growth factors in mesenchymal cells. Despite some notable differences of the studies, the overall findings suggest a positive effect of PRF on cell proliferation, migration, adhesion, differentiation, and inflammation pointing towards a therapeutic potential in regenerative dentistry. CLINICAL RELEVANCE: PRF serves as a reservoir of bioactive molecules to support wound healing and bone regeneration. Although the cellular mechanisms by which PRF supports the clinical outcomes remain unclear, in vitro research provides possible explanations. This systematic review aims to provide an update of the existing research on how PRF affects basic physiological processes in vitro. The overall findings suggest that PRF induces cell proliferation, migration, adhesion, and differentiation along with possessing anti-inflammatory properties further supporting its therapeutic potential in wound healing and bone regeneration.

Effects of Short-Chain Fatty Acids on Human Oral Epithelial Cells and the Potential Impact on Periodontal Disease: A Systematic Review of In Vitro Studies.

Short-chain fatty acids (SCFA), bacterial metabolites released from dental biofilm, are supposed to target the oral epithelium. There is, however, no consensus on how SCFA affect the oral epithelial cells. The objective of the present study was to systematically review the available in vitro evidence of the impact of SCFA on human oral epithelial cells in the context of periodontal disease. A comprehensive electronic search using five databases along with a grey literature search was performed. In vitro studies that evaluated the effects of SCFA on human oral epithelial cells were eligible for inclusion. Risk of bias was assessed by the University of Bristol's tool for assessing risk of bias in cell culture studies. Certainty in cumulative evidence was evaluated using GRADE criteria (grading of recommendations assessment, development, and evaluation). Of 3591 records identified, 10 were eligible for inclusion. A meta-analysis was not possible due to the heterogeneity between the studies. The risk of bias across the studies was considered "serious" due to the presence of methodological biases. Despite these limitations, this review showed that SCFA negatively affect the viability of oral epithelial cells by activating a series of cellular events that includes apoptosis, autophagy, and pyroptosis. SCFA impair the integrity and presumably the transmigration of leucocytes through the epithelial layer by changing junctional and adhesion protein expression, respectively. SCFA also affect the expression of chemokines and cytokines in oral epithelial cells. Future research needs to identify the underlying signaling cascades and to translate the in vitro findings into preclinical models.

Butyrate Decreases ICAM-1 Expression in Human Oral Squamous Cell Carcinoma Cells.

Short-chain fatty acids (SCFA) are bacterial metabolites that can be found in periodontal pockets. The expression of adhesion molecules such as intercellular adhesion molecule-1 (ICAM-1) within the epithelium pocket is considered to be a key event for the selective transmigration of leucocytes towards the gingival sulcus. However, the impact of SCFA on ICAM-1 expression by oral epithelial cells remains unclear. We therefore exposed the oral squamous carcinoma cell line HSC-2, primary oral epithelial cells and human gingival fibroblasts to SCFA, namely acetate, propionate and butyrate, and stimulated with known inducers of ICAM-1 such as interleukin-1-beta (IL1ß) and tumor necrosis factor-alfa (TNFα). We report here that butyrate but not acetate or propionate significantly suppressed the cytokine-induced ICAM-1 expression in HSC-2 epithelial cells and primary epithelial cells. The G-protein coupled receptor-43 (GPR43/ FFAR2) agonist but not the histone deacetylase inhibitor, trichostatin A, mimicked the butyrate effects. Butyrate also attenuated the nuclear translocation of p65 into the nucleus on HSC-2 cells. The decrease of ICAM-1 was independent of Nrf2/HO-1 signaling and phosphorylation of JNK and p38. Nevertheless, butyrate could not reverse an ongoing cytokine-induced ICAM-1 expression in HSC-2 cells. Overall, these observations suggest that butyrate can attenuate cytokine-induced ICAM-1 expression in cells with epithelial origin.

Dental caries is associated with severe periodontitis in Chilean adults: a cross-sectional study.

BACKGROUND: The co-occurrence of caries and periodontitis and a possible association is still a matter of debate. Thus, the aim of the study was to determine the co-occurrence of caries and periodontitis in Chilean adults. METHODS: Evaluation of periodontal and dental status in 994 adults (35-44 years old) based on the First Chilean National Examination Survey 2007-2008. The prevalence of caries was defined as the percentage of participants with one or more teeth with untreated caries by using the D component of the DMFT index (DT ≠ 0). The prevalence of periodontitis was determined using standard case definitions for population-based surveillance of periodontitis described by the CDC-AAP. RESULTS: Individuals with caries had an approximately 40% higher prevalence of severe (29.3% vs 20.8%, p < 0.05) and a 13% higher prevalence of total periodontitis (89.3% vs 78.4%, p < 0.05) than those without caries. Ordinal logistic regression revealed a positive association between periodontitis and the number of teeth with caries (DT ≠ 0; 3 or 4 teeth with caries: OR 1.74; CI = 1.12-2.29 p < 0.05; 5 or more teeth with caries: OR 2.47; CI = 1.66-3.67 p < 0.01). CONCLUSION: Dental caries is associated with the severity and prevalence of periodontitis in Chilean adults. Individuals with 3 or more teeth with untreated caries are more likely to suffer from periodontal disease.

The use of platelet-rich plasma to enhance the outcomes of implant therapy: A systematic review.

OBJECTIVE: To assess the effect of platelet-rich plasma (PRP) on implant dentistry. The primary focused question was as follows: What are the clinical, histological, and radiographic outcomes of PRP administration for bone regeneration and implant therapy? METHODS: A literature search was conducted involving three databases: MEDLINE, EMBASE and Cochrane database followed by a hand search of relevant scientific journals. Human studies using PRP for bone regeneration and implant therapy were considered and articles published up to December 31, 2017 were included. Eligible studies were selected based on the inclusion criteria, and quality assessments were conducted. RESULTS: In total, out from the 9,497 titles meeting the original search criteria, 22 fulfilled the inclusion criteria and were chosen for data extraction. Among them were 15 randomized controlled trials (RCT) and seven controlled clinical trials (CCT). Overall, the risk of bias was moderate to high. A total of seven studies showed superior outcomes when PRP was added during sinus floor elevation and five showed no superior outcome. Three studies found a significant advantage of PRP for alveolar bone regeneration and another three studies for soft tissue healing. Three studies reported on beneficial effects of PRP directly during implant placement while another study failed to find significant differences. Due to the heterogeneity of study designs, no meta-analysis could be performed. SUMMARY AND CONCLUSIONS: Despite the lack of consistent evidence supporting the clinical benefit of PRP in healthy patients, PRP might have a positive effect on wound healing and bone regeneration in compromised patients.

The use of platelet-rich fibrin to enhance the outcomes of implant therapy: A systematic review.

OBJECTIVE: To assess the impact of platelet-rich fibrin (PRF) on implant dentistry. The primary focused question was as follows: What are the clinical, histological, and radiographic outcomes of PRF administration for bone regeneration and implant therapy? METHOD: A systematic literature search comprised three databases: MEDLINE, EMBASE, and Cochrane followed by a hand search of relevant scientific journals. Human studies using PRF for bone regeneration and implant therapy were considered and articles published up to December 31, 2017 were included. Eligible studies were selected based on the inclusion criteria. Randomized controlled trials (RCT) and controlled clinical trials (CCT) were included. RESULTS: In total, 5,963 titles were identified with the search terms and by hand search. A total of 12 randomized controlled trials (RCT) met the inclusion criteria and were chosen for data extraction. Included studies focused on alveolar ridge preservation after tooth extraction, osseointegration process, soft tissue management, bone augmentation, bone regeneration after sinus floor elevation and surgical peri-implantitis treatment. Overall, the risk of bias was moderate or unclear. Nine studies showed superior outcomes for PRF for any of the evaluated variables, such as ridge dimension, bone regeneration, osseointegration process, soft tissue healing. Three studies failed to show any beneficial effects of PRF. No meta-analysis could be performed due to the heterogeneity of study designs. CONCLUSIONS: There is moderate evidence supporting the clinical benefit of PRF on ridge preservation and in the early phase of osseointegration. It remains unclear whether PRF can reduce pain and improve soft tissue healing. More research support is necessary to comment on the role of PRF to improve other implant therapy outcomes.

Alveolar ridge changes 1-year after early implant placement, with or without alveolar ridge preservation at single-implant sites in the aesthetic region: A secondary analysis of radiographic and profilometric outcomes from a randomized controlled trial.

OBJECTIVES: To assess both the radiographic and profilometric outcomes of early implant placement with or without alveolar ridge preservation (ARP) (using two different ARP techniques) after 1 year of loading. MATERIALS AND METHODS: Seventy-five patients with a failing single tooth in the anterior maxilla were randomly allocated to three groups (1:1:1): (a) ARP using demineralized bovine bone mineral containing 10% collagen (DBBM-C) covered by a collagen matrix (CM), (b) ARP using DBBM-C covered with a palatal graft (PG), and (c) unassisted socket healing (control). Eight weeks after tooth extraction, early implant placement was performed in all patients. Cone-beam computed tomography (CBCT) and impressions were taken 8 weeks after tooth extraction (ARP/unassisted healing) prior to implant placement and 1-year post-loading. Radiographic and profilometric outcomes were evaluated. RESULTS: Out of the 70 patients available for re-examination at 1-year post-loading, 55 datasets could be assessed (ARP-CM 19; ARP-PG 17; Control 19). The need for additional guided bone regeneration (GBR) at implant placement amounted to 31.6% (ARP-CM), 29.4% (ARP-PG), and 68.4% (unassisted healing). Adjusted models revealed that residual buccal bone height and additional GBR at implant placement significantly influenced the magnitude of the alveolar changes at 1 year (p < 0.05). In patients with ARP (group ARP-CM or ARP-PG) without additional GBR, the presence of bone convexity amounted to 36.0% (9/25) at 1-year post-loading. For patients that received ARP and additional GBR at implant placement, the frequency of bone convexity increased to 72.7% (8/11) (p = 0.042). Regarding profilometric measurements, a tendency toward agreement with radiographic outcomes was observed. CONCLUSIONS: Early implant placement with ARP can attenuate alveolar ridge changes at 1-year post loading by minimizing both radiographic and profilometric alterations. However, early implant placement with simultaneous GBR consistently yields superior radiographic and profilometric outcomes, regardless of whether ARP is performed.