Biomedical subjects

Magda Feres

Publications and source records attributed to Magda Feres.

11 recordsLinked to original sources

PubMed2007

Influence of implant surface topography on early osseointegration: a histological study in human jaws.

The purpose of this study was to evaluate the influence of the oxidized surface on bone-to-implant contact (BIC%), the bone density in the threaded area (BA%), as well as the bone density outside the threaded area (BD%) in human jaws after 2 months of unloaded healing. Thirteen subjects (mean age 42.61 +/- 6.15 years) received two microimplants (2.5 mm diameter and 6 mm length) each, during conventional mandible or maxilla implant surgery. The microimplants with commercially pure titanium surfaces (machined) and oxidized surfaces served as the control and test surfaces, respectively. After 2 months, the microimplants and the surrounding tissue were removed and prepared for histomorphometric analysis. All microimplants, except two machined and one oxidized microimplant surfaces, were found to be clinically stable after the healing period. Histometric evaluation indicated that the mean BIC% was (21.71 +/- 13.11)% and (39.04 +/- 15.75)% for machined and oxidized microimplant surfaces, respectively. The BD% was higher for the oxidized surface, although there was no difference for maxilla and mandible. The oxidized surface impacted the BA% for the type-IV bone. Data suggest that the oxidized surface presented a higher bone-to-implant contact rate compared with machined surfaces under unloaded conditions, after a healing period of 2 months.

Adult↗

PubMed2006

Scaling and root planing and chlorhexidine mouthrinses in the treatment of chronic periodontitis: a randomized, placebo-controlled clinical trial.

OBJECTIVE: Evaluation of the clinical and microbiological effects of scaling and root planing (SRP) alone or in combination with 0.12% chlorhexidine (CHX) rinsing. METHODS: A blind, placebo-controlled, parallel-design, randomized clinical trial was conducted in 29 subjects with chronic periodontitis. Subjects were assigned to two therapeutic groups: control (SRP+placebo) and test (SRP+CHX during and up to 42 days post-therapy). Clinical and microbiological [N-benzoyl-dl-arginine-2-naphthylamide (BANA test)] examinations were performed at baseline, 42 and 63 days post-therapy. RESULTS: Initially, intermediate sites (4-6 mm) in the test group showed less plaque accumulation, gingival bleeding, bleeding on probing and a greater reduction in attachment level and probing depth (PD) at 63 days after treatment. The initially deep sites (>6 mm) in the CHX group also showed a better reduction in plaque accumulation and in PD compared with the control group. Both therapies led to a microbiological improvement; however, the test subjects showed a higher frequency of BANA-negative sites after treatment, which was sustained over time (p<0.001). At 63 days, the control group presented 25 BANA-negative sites and 65 positive sites, and the test group 58 and 26, respectively. CONCLUSION: The combination of CHX rinses and SRP leads to clinical benefits and to a better reduction in BANA-positive species.

Adult↗

PubMed2006

Histologic evaluation of early human bone response to different implant surfaces.

BACKGROUND: Studies have demonstrated that roughened dental implant surfaces show firmer bone fixation and an increased percentage of bone-to-implant contact (BIC%) compared to commercially pure titanium-surface (machined) implants. Therefore, the purpose of this study was to evaluate the influence of implant-surface topography on human bone tissue after 2 months of unloaded healing. METHODS: Fourteen subjects with a mean age of 46.87 +/- 9.45 years received two microimplants each (2.5 mm in diameter and 6 mm in length), one test (sandblasted acid-etched surface) and one control (machined surface), either in the mandible or in the maxilla. After a healing period of 2 months, the microimplants and surrounding tissues were removed with a trephine bur and prepared for histologic analysis. RESULTS: All microimplants, except for one of the controls, were clinically stable after the healing period. Histometric evaluation indicated that the mean BIC% was 23.08% +/- 11.95% and 42.83% +/- 9.80% for machined and rough microimplant surfaces, respectively (P = 0.0005). The bone area within the threads was also higher for sandblasted-surface implants (P = 0.0005). The mean percentage of bone density did not differ between the two groups (P = 0.578). CONCLUSION: Data from the present histological study suggest that the sandblasted acid-etched implant provides a better human bone tissue response than machined implants under unloaded conditions after a healing period of 2 months.

Acid Etching, Dental↗

PubMed2006

Microbiota of the dorsum of the tongue after plaque accumulation: an experimental study in humans.

BACKGROUND: The purpose of the present investigation was to determine the effect of the absence of tongue hygiene on the microbiota of the dorsum of the tongue. METHODS: Ten volunteers (aged 19 to 22 years) entered the study at baseline and were instructed to abstain from tongue cleaning for 7 days, followed by a period of 3 days without any kind of oral hygiene. Subsequently, a period of 21 days of washout was employed, and this protocol was repeated three times. Microbiological samples were obtained from the dorsum of the tongue at baseline and at the end of the period of coating accumulation and analyzed using the checkerboard DNA-DNA hybridization technique. RESULTS: The species found in highest mean counts at baseline and day 10 were Prevotella melaninogenica and Veillonella parvula. The mean bacterial total counts enhanced significantly during the study (from 17.1x10(6) to 33.7x10(6)). Proportions of red and blue complexes and levels of 18 species also increased after the period of coating accumulation, including several periodontal pathogens, such as Prevotella intermedia, Prevotella nigrescens, Streptococcus constellatus, Tannerella forsythensis, Porphyromonas gingivalis, Treponema denticola, and P. melaninogenica. CONCLUSION: The tongue surface could be an important reservoir for periodontal pathogens and may play a role in the recolonization of tooth surfaces and in the etiology of oral halitosis.

Actinobacillus↗

PubMed2006

Clinical evaluation of tunneled molars: a retrospective study.

BACKGROUND: The main concern associated with the tunneling procedure is the development of root caries on the furcation area post-treatment. The objective of this study was to evaluate the periodontal conditions and the prevalence of root caries in tunneled molars. METHODS: The study sample comprised 30 tunneled teeth (mean tunneling age = 3.6 years) in 18 subjects who had received periodontal treatment and were enrolled in a maintenance program that included the application of fluoride to the exposed root surfaces. Plaque index (PI), pocket depth (PD), bleeding on probing (BOP), decayed, missing, filled or sound teeth (DMFT) and demographic characteristics were assessed. Statistical analysis was performed using the Friedman and Mann-Whitney tests and multiple linear regression analyses. RESULTS: Four teeth (13.4%) showed active root caries inside the tunnels. Six (5.4%) of the 109 root surfaces facing the furcation region (inner surfaces) were affected by carious lesions, similar to the amount of root caries observed on the outer tunnel root surfaces, where 10 (5.3%) of the 189 surfaces studied were restored (p > 0.05). The interior of the tunnels had a higher percentage of sites with PD > or =6 mm then the exterior (p > 0.05). However, the plaque indexes and BOP scores were low for both the internal and external surfaces of the tunnels. Regression analysis indicated that the only positive association with the development of caries inside the tunnels was previous root caries experience (beta = -0.671; p = 0.01). CONCLUSION: The results show that tunneling is a suitable technique to treat periodontal furcation lesions in individuals following a regular maintenance program.

Adult↗

PubMed2005

Presence of Actinobacillus actinomycetemcomitans on the Community Periodontal Index (CPI) teeth in periodontally healthy individuals.

The aim of this study was to compare the prevalence of Actinobacillus actinomycetemcomitans (A. actinomycetemcomitans) located at Community Periodontal Index (CPI) teeth versus randomly selected teeth to determine if the CPI teeth are representative of this bacteria subgingival colonization in periodontally healthy young individuals. Forty-four individuals between 18 and 27 years of age were included in the study (mean age 23.11 +/- 2.91 years). Pooled subgingival plaque samples were collected with paper points from the mesio-buccal aspect of the CPI teeth (10 teeth for adults and 6 teeth for persons under 20 years of age) and transported in reduced Ringer's solution to the culture medium. Sixty days following the first microbial analysis, new pooled microbial samples were obtained from the mesio-buccal aspect of 10 or 6 randomly selected teeth. The presence of A. actinomycetemcomitans was determined using a selective culture medium. Microbiological data were assessed by the Wilcoxon test (p < 0.05). A border line significance (p=0.51) was observed between CPI teeth and randomly selected teeth in terms of detecting the subgingival occurrence of A. actinomycetemcomitans. CPI teeth showed to be representative of A. actinomycetemcomitans subgingival colonization. Therefore, these results suggest that in periodontally healthy young individuals, CPI teeth could be an appropriate source of samples for the subginginval detection of this pathogen.

Adolescent↗

PubMed2005

Oral health impacts on daily living related to four different treatment protocols for chronic periodontitis.

BACKGROUND: The aims of this study were to evaluate the oral health impacts perceived by patients submitted to different treatments of chronic periodontitis and their association with clinical parameters. METHODS: Sixty patients were assigned to one of the following therapeutic groups: control, treated with full-mouth scaling and root planing (SRP); test 1, treated with SRP and 400 mg systemically administered metronidazole (MET) three times per day for 10 days; test 2, treated with SRP and professional supragingival plaque removal (PP) every week for 3 months; and test 3, treated with SRP and MET plus PP. Clinical periodontal measurements and data regarding patients' oral health impacts (perceived impacts on bleeding gums, gingival recession, sensitivity to cold, packing foods, aesthetics, bad breath, and tooth mobility) were collected at baseline and 3 months after therapy. RESULTS: All groups presented significant improvement in oral health perceived impacts. There was no statistically significant difference in the improvement of oral health impacts among groups subjected to different treatments. The clinical data of percentage of deep probing depth, deep clinical attachment level, and bleeding on probing were found to be correlated significantly with oral health impacts. CONCLUSIONS: Periodontal treatment leads to a significant reduction of self-perceived impacts regardless of the non-surgical treatment protocol employed. Most of the clinical data were associated with oral health impacts.

Activities of Daily Living↗

PubMed2005

Detection of Actinobacillus actinomycetemcomitans in unstimulated saliva of patients with chronic periodontitis.

BACKGROUND: The use of whole saliva has shown to be promising in detecting Actinobacillus actinomycetemcomitans out of the subgingival environment. The objective of the present study was to evaluate the use of unstimulated saliva in detecting A. actinomycetemcomitans and to compare the subgingival and extracrevicular occurrence of this pathogen in Brazilian subjects with chronic periodontitis. METHODS: Sixty-six patients (mean age 38.01 9.28 years) with advanced generalized chronic periodontitis were sampled. Subgingival plaque samples were collected from eight sites per patient representing the two deepest sites of each quadrant. Samples of the mucous surfaces, including dorsal surface of the tongue and cheek, were collected with a sterile swab and placed in a microtube containing a reduced solution. Samples of unstimulated saliva were also collected in sterile tubes and 0.1 ml of whole saliva was diluted in 1 ml of reduced solution. The presence of A. actionomycetemcomitans was established using bacterial culture in trypticase soy bacitracin vancomycin selective media. Polymerase chain reaction (PCR) was used to differentiate highly from minimally leukotoxic strains in patients who presented A. actinomycetemcomitans in at least two sampled sites. RESULTS: A. actinomycetemcomitans was isolated from 63.63% of subgingival samples, 56.06% of saliva samples, and 45.45% of samples from mucous surfaces. No statistical difference was observed between subgingival and salivary occurrence of the microorganism. Linear regression showed an association between subgingival plaque and saliva (r(2) = 0.897; P = 0.015) and mucous membrane and saliva (r(2) = 0.152; P = 0.024). The same A. actinomycetemcomitans leukotoxic profile was observed in all sampled sites for a given patient. CONCLUSION: These results suggest that in advanced periodontitis, unstimulated saliva is representative of pooled subgingival plaque samples and its use is appropriate in the oral detection of A. actinomycetemcomitans.

Adult↗

PubMed2005

In vitro antimicrobial activity of plant extracts and propolis in saliva samples of healthy and periodontally-involved subjects.

The aim of the present study was to determine, in vitro, the antimicrobial effect of plant extracts and propolis in saliva samples of 25 periodontally healthy subjects and 25 subjects with chronic periodontitis. One saliva sample from each subject was collected and spread on the surface of trypticase soy agar plates. Paper filter discs containing clove, sage, propolis, chlorhexidine 0.12% (positive control) and distilled water (negative control) were placed onto the plates, and incubated anaerobically for 72 hours. Significant differences in the antimicrobial effects of the different substances were tested using paired t-tests and the Spearman correlation coefficient, while differences in the effects of the extracts in periodontally healthy and diseased subjects were tested using Student's t-test. The highest means, in terms of size of microbial inhibition zones (cm) were obtained with chlorhexidine, followed by pure propolis, clove, and sage in subjects with periodontal health (1.35 +/- 0.22, 1.20 +/- 0.20, 0.94 +/- 0.14 and 0.44 +/- 0.38, respectively) or disease (1.38 +/- 0.23, 1.17 +/- 0.21, 0.94 +/- 0.07 and 0.78 +/- 0.07, respectively). There was a positive correlation between the inhibitory action of 11% propolis (w/v) and chlorhexidine (rho = 0.735, p < 0.001) in diseased subjects. The antimicrobial effects of clove and sage, particularly the latter, were less marked in comparison to propolis and chlorhexidine in both groups of subjects. In conclusion, propolis showed significant antimicrobial properties in saliva samples from periodontally healthy and diseased subjects, suggesting that this substance may be used therapeutically in the future to inhibit oral microbial growth.

Adult↗

PubMed2002

Microbial profile on metallic and ceramic bracket materials.

The placement of orthodontic appliances creates a favorable environment for the accumulation of a microbiota and food residues, which, in time, may cause caries or exacerbate any pre-existing periodontal disease. The purpose of the present study was to compare the total bacterial counts present on metallic and ceramic orthodontic brackets in order to clarify which bracket type has a higher plaque retaining capacity and to determine the levels of Streptococcus mutans and Lactobacillus spp on both types of brackets. Thirty-two metallic brackets and 24 ceramic brackets were collected from orthodontic patients at the day of debonding. Two brackets were collected from each patient; one from a maxillary central incisor and another from a maxillary second premolar. Sixteen patients who used metallic brackets and 12 patients who used ceramic brackets were sampled. Bacterial populations were studied using "checkerboard" DNA-DNA hybridization, which uses DNA probes to identify species in complex microbial samples. The significance of differences between groups was determined using the Mann-Whitney U-test. Results showed no significant differences between metallic and ceramic brackets with respect to the caries-inducing S mutans and L acidophilus spp counts. Mean counts of 8 of 35 additional species differed significantly between metallic and ceramic brackets with no obvious pattern favoring one bracket type over the other. This study showed higher mean counts of Treponema denticola, Actinobacillus actinomycetemcomitans, Fusobacterium nucleatum ss vincentii, Streptococcus anginosus, and Eubacterium nodatum on metallic brackets while higher counts of Eikenella corrodens, Campylobacter showae, and Selenomonas noxia were found on ceramic brackets.

Aggregatibacter actinomycetemcomitans↗

PubMed2002

The effect of apically repositioned flap surgery on clinical parameters and the composition of the subgingival microbiota: 12-month data.

The purpose of this investigation was to examine the clinical and microbiologic effects of apically repositioned flap surgery. Eighteen patients with chronic periodontitis received initial preparation (IP) including scaling and root planing, followed at 3 months by apically repositioned flap surgery at sites with pocket depth > 4 mm. Subjects were monitored clinically and microbiologically at baseline, 3 months after IP, and at 3, 6, 9, and 12 months postsurgery. Clinical assessments of plaque accumulation, gingival redness, suppuration, bleeding on probing, pocket depth, and attachment level were made at six sites per tooth. Subgingival plaque samples were taken from the mesial aspect of each tooth, and the presence and levels of 40 subgingival taxa were determined using checkerboard DNA-DNA hybridization. Significant reductions were seen in mean pocket depth and percentage of sites exhibiting gingival redness and bleeding on probing in both sites that received IP only and in sites receiving IP followed by surgery. Mean attachment level increased significantly for both sets of sites, but the increase was greater at the surgically treated sites. The total DNA probe counts were significantly reduced at sites in both treatment groups. At surgically treated sites, 19 of 40 taxa were significantly reduced posttherapy At sites receiving IP only, 16 species were significantly reduced over time. While there were some reductions in mean counts after IP in this site group, the major reductions occurred after the surgical phase in these patients, even though these particular sites did not receive surgical therapy. The reduction in pocket depth by surgical means and the associated decrease in reservoirs of periodontal pathogens may be important in achieving sustained periodontal stability.

Adult↗