Late complications after root coverage with two types of subepithelial connective tissue grafts, clinical and histopathological evaluation: A prospective cohort study.

AIM: This prospective cohort study evaluated late complications (LC) on recipient sites comparing two types of connective tissue grafts (CTG). MATERIALS AND METHODS: Participants (n: 60) were treated with coronally advanced flap (CAF) plus CTG harvested by de-epithelialized technique (DE) (n:31) or two-parallel incision (PI) (n:29). Areas were evaluated to identify white discharge associated or not with gingival cul-de-sac. Patients were ordered in groups with (DE+and PI+) or without (DE- and PI-) LC. Biopsies for histopathological analysis in LC areas were proposed. RESULTS: Six cases exhibited LC, 5 in DE graft (DE+) and 1 in PI graft (PI+) group; 2 were diagnosed at 3 months postoperatively, 3 at 6 months and one at 12 months. The relative risk for LC was 1.7 times greater for DE graft (p: 0.01; CI: 1.10 to 2.72; RR>1). Differences were not observed for clinical outcomes after both types of CTGs (p > 0.05). Biopsies showed deep invagination of the epithelial lining suggesting cyst-like area/ cavity with keratin content and consolidated in fibrous connective tissue. After 24 months biopsied areas presented no recurrence of LC, in non-biopsied patients the clinical condition remained unchanged. CONCLUSIONS: Considering the limitations of this study, LC on recipient sites demonstrated no statistical difference between two types of CTG.

Laser and LED photobiomodulation effects in osteogenic or regular medium on rat calvaria osteoblasts obtained by newly forming bone technique.

The purposes of this study are to evaluate the effects of photobiomodulation (PBM) with laser and LED on rat calvaria osteoblasts (rGO lineage), cultured in osteogenic (OST) or regular (REG) medium, after induction of a quiescent state and to test if PBM is capable of osteogenic induction and if there is a sum of effects when combining OST medium with PBM. Before irradiation, the cells were put in a quiescent state (1% FBS) 24 h, when red (AlGaInP-660 nm) and infrared laser (GaAlAs-808 nm) and LED (637 ± 15 nm) were applied. The groups were as follows: red laser (RL3-5 J/cm2, 3 s and RL5-8.3 J/cm2, 5 s, 1.66 W/cm2); infrared laser (IrL3-5 J/cm2, 3 s and IrL5-8.3 J/cm2, 5 s); LED (LED3-3 s and LED5-5 s, 0.02 J/cm2, 0.885 W/cm2); positive (C+, 10% FBS) and negative control (C-, 1% FBS). For alkaline phosphatase (ALP) and mineralization assays, the cells were cultured in REG (DMEM 10% FBS) and OST medium (DMEM 10% FBS, 50 µg/mL ascorbic acid, 10 mM ß-glycerophosphate). Statistical analysis was performed using ANOVA and Tukey's tests (p < 0.05). RL5 and LED5 increased proliferation, in vitro wound closure, ALP, and mineralization in rGO cells (p < 0.05). PBM with red laser and LED induced mineralization by itself, without osteogenic medium, not observed for infrared laser (p < 0.05). A sum of effects was observed in osteogenic medium and PBM by infrared, red laser, and LED (5 s). Red laser and LED increased proliferation, migration, and secretory phases in rGO cells in a dose-dependent manner. PBM with red laser and LED promotes osteogenic induction by itself. PBM with infrared laser and osteogenic medium potentializes mineralization.

Free gingival graft and acellular dermal matrix for gingival augmentation: a 15-year clinical study.

OBJECTIVES: This study evaluated clinical outcomes of acellular dermal matrix (ADM) allograft compared with autogenous free gingival graft (FGG) for gingival augmentation after 15 years. MATERIAL AND METHODS: Twenty-two patients were originally included and evaluated by de Resende et al. (Clin Oral Investig 23:539-550, 2019), and 12 accepted to participate in this longitudinal evaluation. Clinical parameters evaluated were recession depth (RD), probing depth (PD), clinical attachment level (CAL), keratinized tissue width (KTW), and soft tissue thickness (TT). In addition, esthetic perception was evaluated by patients and by a calibrated periodontist. Data were evaluated by ANOVA complemented by Tukey tests (p < 0.05). RESULTS: After 15 years, both treatments provided a significant increase in KTW and TT but with superior results for the FGG group (p < 0.05). No differences were observed between groups for PD and CAL. In the ADM group, RD significantly increased in long term, as well as the rate of tissue contraction. The percentage of shrinkage for the ADM group was 59.6%. Conversely, the FGG group presented a creeping attachment of 17.6% and RD significantly decreased in long term. The ADM group presented superior results considering professional esthetic perception. CONCLUSIONS: Both treatments longitudinally promoted significant gain of keratinized tissue width and thickness with superior outcomes for the FGG group. The ADM group demonstrated more tissue contraction and gingival recession whereas the FGG group presented creeping attachment. Professional esthetic perception was superior for the ADM group. CLINICAL RELEVANCE: This study added important clinical data with long-term evaluation of ADM compared with FGG.

Acellular dermal matrix allograft versus free gingival graft: a histological evaluation and split-mouth randomized clinical trial.

OBJECTIVES: This split-mouth controlled randomized clinical trial evaluated clinical and histological results of acellular dermal matrix allograft (ADM) compared to autogenous free gingival graft (FGG) for keratinized tissue augmentation. MATERIAL AND METHODS: Twenty-five patients with the absence or deficiency of keratinized tissue (50 sites) were treated with FGG (control group) and ADM (test group). Clinical parameters included keratinized tissue width (KTW) (primary outcome), soft tissue thickness (TT), recession depth (RD), probing depth (PD), and clinical attachment level (CAL). Esthetic perception was evaluated by patients and by a calibrated periodontist using visual analog scale (VAS). Histological analysis included biopsies of five different patients from both test and control sites for each evaluation period (n = 25). The analysis included percentage of connective tissue components, epithelial luminal to basal surface ratio, tissue maturation, and presence of elastic fibers. Data were evaluated by ANOVA complemented by Tukey's tests (p < 0.05). RESULTS: After 6 months, PD and CAL demonstrated no differences between groups. ADM presented higher RD compared to FGG in all periods. Mean tissue shrinkage for control and test groups was 12.41 versus 55.7%. TT was inferior for ADM group compared to FGG. Esthetics perception by professional evaluation showed superior results for ADM. Histomorphometric analysis demonstrated higher percentage of cellularity, blood vessels, and epithelial luminal to basal surface ratio for FGG group. ADM group presented higher percentage of collagen fibers and inflammatory infiltrate. CONCLUSIONS: Both treatments resulted in improvement of clinical parameters, except for RD. ADM group presented more tissue shrinkage and delayed healing, confirmed histologically, but superior professional esthetic perception. CLINICAL RELEVANCE: This study added important clinical and histological data to contribute in the decision-making process between indication of FGG or ADM.

Comparison of the effect of root surface modification with citric acid, EDTA, and aPDT on adhesion and proliferation of human gingival fibroblasts and osteoblasts: an in vitro study.

Root demineralization is used in Periodontics as an adjuvant for mechanical treatment. The aim of this study was to evaluate the effects of root surface modification with mechanic, chemical, and photodynamic treatments on adhesion and proliferation of human gingival fibroblasts and osteoblasts. Root fragments were treated by scaling and root planing (C-control group), EDTA (pH 7), citric acid plus tetracycline (CA-pH 1), and antimicrobial photodynamic therapy (aPDT) with toluidine blue O and red laser (pH 4). Cells were seeded (104 cells/well, 6th passage) on root fragments of each experimental group and cultured for 24, 48, and 72 h. Cells were counted in scanning electron microscopy images by a calibrated examiner. For fibroblasts, the highest number of cells were present at 72-h period (p < 0.05). EDTA group showed a very low number of cells in relation to CA group (p < 0.05). CA and aPDT group presented higher number of cells in all periods, but without differences between other treatment groups (p > 0.05). For osteoblasts, there was a significant increase in cell numbers for aPDT group at 72 h (p < 0.05). In conclusion, aPDT treatment provided a positive stimulus to osteoblast growth, while for fibroblasts, aPDT and CA had a tendency for higher cell growth.

"Aroeira" (Myracrodruon urundeuva) methanol extract: the relationship between chemical compounds and cellular effects.

CONTEXT: "Aroeira" [Myracrodruon urundeuva Allemão (Anacardiaceae)] is a tree whose leaves have been studied for therapeutic purposes in medicine and dentistry. OBJECTIVE: The study chemically identifies the leaf extract of aroeira and determines its effect on human gingival fibroblasts. MATERIALS AND METHODS: An 80% methanol leave extract was obtained by maceration and chemically identified through flow-injection analysis-electrospray ionization-ion trap-tandem mass spectrometry (FIA-ESI-IT-MSn). Cytotoxicity of the aroeira's methanol extract was evaluated in lineage of fibroblasts. Adherent cells were treated with different concentrations of aroeira's methanol extract in the medium: 0.1, 1, 10, 100 and 1000 µg/mL. Control cells were cultivated in the medium only. Analyses were done at 24, 48, 72 and 96 h of culture by neutral red assay; and at 24, 48 and 96 h by crystal violet assay. RESULTS: FIA-ESI-IT-MS analysis determined the presence of compounds, for the first time in the species: quercetin-O-glucuronide and quercetin-O-deoxyhexose-O-glucose in the extract. On one hand, neutral red and crystal violet assay showed a reduction (to 50% up until 100%) of cellular viability of groups of 100 and 1000 µg/mL compared with control at 96 h (p < 0.05). On the other hand, lower concentrations (0.1; 1 and 10 µg/mL) of the extract were similar to that of the control at 96 h (p < 0.05), in general. CONCLUSIONS: In view of the results, we can conclude that the extract of aroeira presents tannins and flavonoids. Furthermore, the extract is capable of modulating the viability of human gingival fibroblasts according to its concentration.

Lasers in periodontal therapy.

About 50 years ago, lasers started to be used in periodontal treatment following evidence that wounds produced in animals healed more quickly after being irradiated with low-intensity lasers. Increased production of growth factors, stimulated mainly by red and infrared lasers, may participate in this process by influencing the behavior of various types of cells. High-intensity lasers have been used as an alternative to nonsurgical periodontal therapy in root biomodification and to reduce dentin hypersensivity; low-intensity lasers are frequently employed to improve tissue repair in regenerative procedures and in antimicrobial photodynamic therapy. Despite the abundance of promising data on the advantages of their use, there is still controversy regarding the real benefits of lasers and antimicrobial photodynamic therapy in periodontal and peri-implant treatment. A huge variation in the parameters of laser application among studies makes comparisons very difficult. An overview of the current concepts and findings on lasers in periodontal therapy is presented with emphasis on data collected from Latin-American researchers.

Cyanoacrylate Adhesive as an Alternative Tool for Membrane Fixation in Guided Tissue Regeneration.

AIM: To report a well succeeded use of cyanoacrylate adhesive for fixating a resorbable membrane during a guided tissue regeneration procedure (GTR). BACKGROUND: The immobilization of membranes in GTR is essential for establishing proper environment for cell differentiation and tissue regeneration. However, some membranes are very difficult to be kept in position by sutures and its fixation by mini screws or pins may be time consuming and expensive. CASE DESCRIPTION: A 47-year-old woman presenting a vertical bone defect at the palatal aspect of the left central incisor was treated by GTR using particulate autogenous bone graft associated to a collagen membrane. The membrane was glued to the bone surrounding the defect and to the tooth surface with cyanoacrylate adhesive. The postoperative period was uneventful and 4 years later, excellent results in terms of radiographic filling of the defect and reduction of the probing depth were seen. For illustrative purposes, histological findings obtained during a previous experiment in calvaria of guinea pigs is shown, characterizing a foreign body granuloma and proving that the cyanoacrylate adhesive is a safe tool in GTR. CONCLUSION: The use of a membrane glued with cyanoacrylate to immobilize membranes in GTR is viable and safe from both technical and biological standpoints and may be advantageous for clinical and research purposes. CLINICAL SIGNIFICANCE: The alternative method for membrane fixation shown in this case report can contribute to simplify the technique in GTR procedures.

Laser and light-emitting diode effects on pre-osteoblast growth and differentiation.

The acceleration of bone regeneration by low-intensity laser irradiation may hold potential benefits in clinical therapy in orthopedics and dentistry. The purpose of this study is to compare the effects of light-emitting diode (LED) and laser on pre-osteoblast MC3T3 proliferation and differentiation. Cells were irradiated with red, infrared, and LED (3 and 5 J/cm(2)). Lasers had a power density of 1 W/cm(2) and irradiation time of 2 and 5 s. LED had a power density of 60 mW/cm(2) and irradiation time of 50 and 83 s. Control group did not receive irradiation. Cell growth was assessed by a colorimetric test (MTT) (24, 48, 72, and 96 h), and cell differentiation was evaluated by alkaline phosphatase (ALP) quantification after growth in osteogenic medium (72 and 96 h and 7 and 14 days). At 24 h, the cell growth was enhanced 3.6 times by LED (5 J/cm(2)), 6.8 times by red laser (3 J/cm(2)), and 10.1 times by red laser (5 J/cm(2)) in relation to control group (p < 0.05). At the other periods, there was no influence of irradiation on cell growth (p > 0.05). The production of ALP was not influenced by irradiation at any period of time (p > 0.05). Low-intensity laser and LED have similar effects on stimulation of cell growth, but no effect on cell differentiation.

Palatal mucosa derived fibroblasts present an adaptive behavior regarding cytokine secretion when grafted onto the gingival margin.

BACKGROUND: Considering that grafted gingival tissue might have to be adapted to the receptor area and that fibroblasts have the ability to respond to bacterial stimuli through the release of various cytokines, this study investigated whether fibroblasts from the palatal mucosa behave differently when grafted onto the gingival margin regarding cytokine secretion. METHODS: Biopsies from the palatal mucosa were collected at the time of free gingival graft surgery, and after four months re-collection was performed upon surgery for root coverage. Fibroblasts were isolated by the explant technique, cultured and stimulated with Porphyromonas gingivalis (Pg) and Escherichia coli (Ec) LPS for 24 or 48 h for comparative evaluation of the secretion of cytokines and chemokines, such as IL-6, IL-8/CXCL8, MIP-1α/CCL3, TGF-ß, VEGF and CXCL16. Unstimulated cells were used as the control group. Cells were tested for viability through MTT assay, and secretion of cytokines and chemokines was evaluated in the cell supernatants by Enzyme-Linked Immunosorbent Assay (ELISA). RESULTS: Fibroblasts from the palatal mucosa maintained the same secretion pattern of IL-6 when grafted onto the gingival margin. On the contrary, fibroblasts from the marginal gingival graft showed increased secretion of IL-8/CXCL8 even in the absence of stimulation. Interestingly, MIP-1α/CCL3 secretion by fibroblasts from the marginal gingival graft was significantly increased after 48 hours of stimulation with Pg LPS and after 24 h with Ec LPS. Only fibroblasts from the marginal gingival graft showed secretion of TGF-ß. VEGF and CXCL16 secretion were not detected by both subsets of fibroblasts. CONCLUSION: Fibroblasts from the palatal mucosa seem to be adapted to local conditions of the site microenvironment when grafted onto the gingival marginal area. This evidence supports the effective participation of fibroblasts in the homeostasis of the marginal periodontium through secretion modulation of important inflammatory mediators.

Antimicrobial photodynamic therapy mediated by methylene blue in surfactant vehicle as adjuvant to periodontal treatment. Randomized, controlled, double-blind clinical trial.

BACKGROUND: Antimicrobial photodymanic therapy mediated by methylene blue has been investigated as an adjunctive to periodontal treatment but the dimerization of photosensitizer molecules reduces the phototoxic effects. Sodium dodecyl sulfate is a surfactant that may control this aggregation. The aim of this study was evaluated the photodynamic effect of methylene blue in sodium dodecyl sulfate in periodontitis. METHODS: 36 participants with periodontitis were selected and allocated randomly in two group for intervention and other two for control - all of them were treated with scaling and root planing before aPDT. Three periodontal evaluations were done: at the selection time, at the day of intervention and thirty-day after this. Pre-irradiation time was 1 min and 2 min for irradiation. Laser (Therapy XT, DMC, São Carlos, Brazil) with wavelength of 660 nm and 100 mW of power was used. Two photosensitizer solutions with 100 µM methylene blue was used, one of them was in water and other in 0,25% of sodium dodecyl sulfate. Two sites of each participant were selected for the experimental procedures. Microbiological evaluations were performed to quantify microorganisms before and immediately after intervention. Quantitative microbiological evaluation was the primary outcome; morphological aspects of bacterial colony, and clinical probing depth was the secondary one. RESULTS: There was no significant difference between the groups in both bacterial reduction and the clinical parameter evaluated. CONCLUSION: The effect of methylene blue in surfactant did not cause enough phototoxic effects that could promote reduction of periodontal pocket depth.

Association among gestational diabetes mellitus, periodontitis and prematurity: a cross-sectional study.

Objective: Gestational diabetes mellitus (GDM) causes maternal and infant morbidity. Periodontitis is associated with adverse pregnancy outcomes. The aim of this study was to evaluate periodontal status, prematurity and associated factors in pregnant women with and without GDM. Methods: This observational cross-sectional study included 80 pregnant women with GDM (G1 = 40) and without GDM (G2 = 40). Demographic and socioeconomic status, systemic and periodontal health condition, prematurity and newborns' birth weight were analyzed. For bivariate analysis, Mann-Whitney U-test, t test and Chi-squared test were used. Binary logistic regression analyzed independent variables for periodontitis and prematurity (p < 0.05). Results: Patients from G1 presented lower socioeconomic status, higher weight and body mass index (BMI). Prematurity (G1 = 27.5%; G2 = 2.5%; p < 0.05) and severe periodontitis percentages (G1 = 22.5%; G2 = 0; p = 0.001) were higher in G1 than in G2. Logistic regression analysis showed that household monthly income (OR = 0.65; 95% CI 0.48-0.86; p = 0.003) and maternal BMI (adjusted OR = 1.12; 95% CI 1.01-1.25; p = 0.028) were significant predictors of periodontitis during the third trimester of pregnancy. Presence of GDM remained in the final logistic model related to prematurity (adjusted OR = 14.79; 95% CI 1.80-121.13; p = 0.012). Conclusion: Pregnant women with GDM presented higher severity of periodontitis, lower socioeconomic status, higher overweight/obesity and a 10-fold higher risk of prematurity. Socioeconomic-cultural status and BMI were significant predictors for periodontitis, and GDM was a predictor to prematurity.

Clinical Outcomes and Gingival Blood Flowmetry of Two Types of Subepithelial Connective Tissue Graft for Root Coverage in Multiple Gingival Recessions: A Preliminary Study.

This randomized split-mouth preliminary clinical trial aimed to evaluate periodontal parameters and gingival blood flowmetry, comparing sites that received subepithelial connective tissue graft from the palate after deepithelialization (DE) or obtained with parallel incision (PI). Periodontal parameters were evaluated at baseline and 6 months postoperative. Gingival blood flows were analyzed by laser Doppler flowmetry (LDF) at baseline and 2, 7, and 14 days postoperative. Statistical and LDF analyses were performed with R version 3.5.1 and MATLAB software, and clinical parameters through ANOVA and Wilcoxon signed-rank tests. LDF showed superior decrease in power spectral density (PSD) for DE after 2 days. After 7 days, PSD returned to initial values only for PI, and DE had not returned to the initial values by day 14. Despite major initial revascularization challenges for DE sites, both grafts promoted satisfactory root coverage in the treatment of multiple gingival recessions.

Impact of Subepithelial Connective Tissue for Root Coverage on Brazilian Patients' Quality of Life: A Longitudinal Clinical Study.

Aims: Gingival recession has been associated with dentin hypersensitivity and aesthetic impairment. The impact of gingival recession and periodontal surgical procedures on adult patients' quality of life are scarce. The aim of this study was to evaluate the quality of life of patients submitted to root coverage procedures with subepithelial connective tissue grafts and coronally advanced flap. Materials and methods: Patients were asked to use a numerical rating scale to classify their dentin hypersensitivity, aesthetics, pain/discomfort, chewing, and brushing abilities in gingival recession sites treated with subepithelial connective tissue grafts plus coronally advanced flap. The patients answered a self-administered questionnaire about quality of life-related to oral health (OHIP-14) after 7, 14, 30, 90, and 180 days. Descriptive statistics were used to synthesize the data recorded. Results: Mean percentage of root coverage was positively related to OHIP-14 (dimension 2- physical pain) in 90 days postoperatively. The quality of life (OHIP-14 total score) significantly improved from baseline to 90 and 180 days postoperatively. The numerical rating score analysis revealed significant improvement in the chewing and brushing abilities when period of 7 days was compared to 90 and 180 days and from 14 to 180 days. Conclusions: Root coverage procedures with subepithelial connective tissue grafts plus coronally advanced flap result in a positive effect on adult patients' quality of life.

Clinical and patient-centered outcomes using two types of subepithelial connective tissue grafts: A split-mouth randomized clinical trial.

BACKGROUND: This split-mouth randomized clinical trial compared two different types of subepithelial connective tissue grafts (SCTG) considering clinical parameters and patient-centered outcomes in patients with bilateral recession type 1 multiple gingival recessions after 6 months postoperatively. METHODS: A total of 21 patients were surgically treated with coronally advanced flap (CAF) associated with SCTG harvested by: double blade scalpel (DBS) and de-epithelialized (DE) SCTG. Periodontal clinical parameters and esthetics were evaluated by a calibrated periodontist at baseline and after 6 months. Patient-centered outcomes related to pain/discomfort and esthetics were assessed with visual analogue scale after 7 days and 6 months, respectively. RESULTS: All clinical parameters, with the exception of probing depth, demonstrated differences in intragroup evaluation, comparing baseline to 6-month evaluation (P <0.05). Both groups presented reduction of recession depth and recession width and gain of keratinized tissue thickness, keratinized tissue width, and clinical attachment level (P <0.05). Intergroup comparison (DBS × DE) demonstrated no significant differences considering clinical parameters and periods. Both techniques improved esthetics evaluated by patients, without a difference between groups in patients and professional analysis. However, DBS group presented inferior pain/discomfort compared with DE (P <0.05). CONCLUSION: DBS and DE associated with CAF presented satisfactory clinical outcomes. However, DBS presented inferior morbidity, an important fact for decision-making process.

Deposition of Immune Complexes in Gingival Tissues in the Presence of Periodontitis and Systemic Lupus Erythematosus.

Systemic lupus erythematosus (SLE) is a complex chronic autoimmune disease characterized by tissue damage and widespread inflammation in response to environmental challenges. Deposition of immune complexes in kidneys glomeruli are associated with lupus nephritis, determining SLE diagnosis. Periodontitis is a chronic inflammatory disease characterized by clinical attachment and bone loss, caused by a microbial challenge - host response interaction. Deposition of immune complex at gingival tissues is a common finding in the course of the disease. Considering that, the primary aim of this study is to investigate the deposition of immune complexes at gingival tissues of SLE patients compared to systemically healthy ones, correlating it to periodontal and systemic parameters. Twenty-five women diagnosed with SLE (SLE+) and 25 age-matched systemically healthy (SLE-) women were included in the study. Detailed information on overall patient's health were obtained from file records. Participants were screened for probing depth (PD), clinical attachment loss (CAL), gingival recession (REC), full-mouth bleeding score (FMBS) and plaque scores (FMPS). Bone loss was determined at panoramic X-ray images as the distance from cementenamel junction to alveolar crest (CEJ-AC). Gingival biopsies were obtained from the first 15 patients submitted to surgical periodontal therapy of each group, and were analyzed by optical microscopy and direct immunofluorescence to investigate the deposition of antigen-antibody complexes. Eleven (44%) patients were diagnosed with active SLE (SLE-A) and 14 (56%) with inactive SLE (LES-I). Mean PD, CAL and FMBS were significantly lower in SLE+ than SLE-(p < 0.05; Mann Whitney). The chronic use of low doses of immunosuppressants was associated with lower prevalence of CAL >3 mm. Immunofluorescence staining of markers of lupus nephritis and/or proteinuria was significantly increased in SLE+ compared to SLE-, even in the presence of periodontitis. These findings suggest that immunomodulatory drugs in SLE improves periodontal parameters. The greater deposition of antigen-antibody complexes in the gingival tissues of patients diagnosed with SLE may be a marker of disease activity, possibly complementing their diagnosis.

Torus palatinus: a graft option for alveolar ridge reconstruction.

The reconstruction of the alveolar ridge with particulate bone collected from the torus palatinus is presented in this case report. Bone loss at the maxillary right permanent central incisor was rehabilitated with an implant-supported fixed prosthesis. The success of this approach demonstrates that the torus palatinus and torus mandibularis, found in approximately 20% and 27% of the population, respectively, are feasible options for bone regeneration, with several advantages compared to other sources of bone. Thus, surgeons should look for these bony growths, which result in surgery with less morbidity when included in the treatment plan.

The concentration of citric acid as dental root conditioner influences the behavior of fibroblasts from human periodontal ligament.

OBJECTIVE: This study investigated the behavior of fibroblasts from human periodontal ligament (hPLF) cultured on dental roots subjected to different protocols of citric acid conditioning. MATERIALS AND METHODS: 32 human teeth extracted due to advanced periodontal disease provided 63 radicular fragments, which were randomly divided in groups according to the treatment given to the surface: rinsing with saline solution for 90 s (C), 10 % citric acid (CA10), or 50 % citric acid (CA50). The treatments were applied during 90 s, 120 s and 180 s (n = 9). hPLF were cultured for 24, 48 and 72 h (n = 3) on the treated samples and analyzed by scanning electron microscopy (SEM) for surface area covered by cells and dentinal tubules widening. RESULTS: Excepting group C, all the other groups showed almost complete coverage of root surface by hPLF with time. At 24 h of cell culture, the largest area of coverage was seen in the samples treated with CA10-90 (98 ± 0.89 %) at 24 h of cell culture and this difference was significant (p < 0.05) in comparison to CA10-180 (84.04 ± 5.01 %), CA50-90 (63.28 ± 12.46 %), CA50-180 (56.59 ± 8.76 %) and C (0.06 ± 0.11 %). In all the other comparisons, there was no statistically significant differences between CA10 and CA50 (p > 0.05). Cells grown on surfaces treated with CA10 were more spread and flatten than in the CA50 specimens. CONCLUSIONS: Periodontally compromised roots surfaces conditioned with 10 % citric acid for 90 s resulted in better substrate for hPLF proliferation, in initial periods of culture than 50 % citric acid. The enlargement of the dentinal tubules did not seem to be influenced by the acid concentration.