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M S Tonetti

Publications and source records attributed to M S Tonetti.

At least 55 records · Page 3Linked to original sources
PubMed1996

Factors affecting the healing response of intrabony defects following guided tissue regeneration and access flap surgery.

Identification and control of significant factors determining clinical outcomes is of paramount importance to improve expected results of a variety of therapeutic procedures. The aim of this investigation was to identify, with a multivariate approach, factors associated with healing outcomes of 3 periodontal surgical procedures in deep intrabony defects. 45 patients with evidence of deep intrabony defects were randomly assigned to 3 treatment groups: access flap (group C), conventional guided tissue regeneration (GTR) with non-resorbable expanded polytetrafluoroethilene (ePTFE) membranes (group B), and GTR with self supporting membranes combined with the modified papilla preservation technique (group A). In both GTR procedures, membranes were positioned coronal to the interproxymal alveolar crest. Primary outcome variables (i.e., probing attachment level gains at 1 year and the amount of newly formed tissue present at membrane removal) were explained in terms of a series of patient, defect morphology and surgical factors, using a multivariate approach. Highly significant treatment effects were observed, indicating that the 3 tested therapeutic modalities resulted in significant differences in primary outcome variables. Detailed analysis assessing the significance of the tested factors in determining the healing outcomes following each procedure was performed with a stepwise elimination approach of non-significant factors. The results indicated that: (i) the need to create and maintain space should be a key objective of regenerative approaches based upon the principles of guided tissue regeneration; (ii) control of patient's oral hygiene and residual periodontal infection in the oral cavity are strongly associated with clinical outcomes of both regenerative and conventional surgical procedures and should receive proper attention.

Adult↗
PubMed1996

Periodontal diagnosis in treated periodontitis. Why, when and how to use clinical parameters.

The objective of clinical periodontal diagnosis in maintenance patients is to monitor the risk for periodontal disease progression. Risk for progression should be continuously monitored at the patient, tooth and site level at each recall appointment. At the patient level, the significance of systemic diseases, cigarette smoking, compliance with the recall program, loss of support in relation to the patient's age, full mouth plaque and/or bleeding scores, and prevalence of residual pockets are of key importance. At the tooth and tooth-site levels, residual periodontal support, inflammatory parameters and their persistence, presence of ecological niches with difficult access such as furcations, and presence of iatrogenic factors have to be put into proportion with the patient's overall risk profile. The information gathered by clinical monitoring and continuous multilevel risk assessment facilitates an immediate appreciation of the periodontal health status of an individual and the possible risk for further infection and/or disease progression in the dentition and at a particular tooth or site.

Age Factors↗
PubMed1996

Periodontal regeneration of human intrabony defects with bioresorbable membranes. A controlled clinical trial.

The purpose of this controlled clinical trial was to compare the clinical efficacy of 3 treatment modalities in the treatment of deep interproximal intrabony defects. Thirty-six (36) defects in 36 patients were randomly assigned to 1 of 3 treatment groups by blocking to prognostic variables. The test was treated with bioresorbable membranes positioned coronal to the interproximal bone crest; the second group (membrane control) was treated with conventional non-resorbable (ePTFE) barrier membranes applied coronal to the alveolar crest; the third group (flap Control) was treated with an access flap procedure (MWF). No differences were observed in terms of baseline oral hygiene and defect characteristics among the 3 groups, indicating that the blocking approach was effective. A stringent infection control program was enforced for 1 year. The results indicated that: 1) at 1 year all treatment modalities resulted in clinically significant improvements in clinical attachment levels (CAL) and reductions in probing depths; 2) a statistically significant treatment effect (P < 0.0001, ANOVA) was observed comparing the test (4.6 +/- 1.2 mm), the membrane control (5.2 +/- 1.4 mm), and the flap control groups (2.3 +/- 0.8 mm) in terms of CAL gain; 3) differences in terms of CAL gain between the test (bioresorbable) and the membrane control (ePTFE) groups were not statistically significant (P = 0.19, t-test); 4) both the test and the membrane control groups gained significantly more CAL at 1 year than the MWF group (P < 0.0001, t-test). CAL gains > or = 4 mm were observed in 83.3% of cases in both GTR groups, while CAL gains of this magnitude were not detected in the MWF group. We concluded that clinically significant CAL gains can be obtained with GTR procedures using both bioresorbable and non-resorbable membranes. Patients' morbidity, however, was lower in the group treated with bioresorbable membranes.

Adult↗
PubMed1996

The modified papilla preservation technique with bioresorbable barrier membranes in the treatment of intrabony defects. Case reports.

A new surgical approach for interproximal regenerative procedures has been utilized in conjunction with bioresorbable barrier membranes in the treatment of deep intrabony defects. The purpose of this study was to test the effectiveness of the modified papilla preservation technique in obtaining and maintaining primary closure of the interdental space over bioresorbable membranes. Ten patients (10 sites) with optimal plaque control were treated according to the modified papilla preservation technique. Baseline probing attachment level and probing pocket depth were 10.1 +/- 1.9 mm and 8.9 +/- 2.4 mm, respectively. The intrabony component of the defects was 6.5 +/- 1.7 mm. Polylactic acid barrier membranes were positioned just coronal to the interproximal bone crest. Primary closure over the membranes was obtained in 100% of the cases. In two cases only a slight dehiscence of the interproximal tissues was observed after 2 weeks. Healing was uneventful in all the treated sites. Probing attachment level gains of 4.5 +/- 0.9 mm and a probing pocket depth reduction of 5.8 +/- 2.3 mm were observed at 1 year. It can be concluded that the modified papilla preservation technique is a suitable alternative for interproximal regenerative procedures in conjunction with bioresorbable barrier membranes.

Adult↗
PubMed1996

Guided tissue regeneration of deep intrabony defects in strategically important prosthetic abutments.

This study reports the clinical outcomes obtained in a longitudinal cohort of 23 patients treated by guided tissue regeneration for strategically important teeth compromised by the presence of deep intrabony defects. After completion of initial periodontal therapy and placement of a provisional fixed partial denture, a nonresorbable e-PTFE membrane was applied to isolate the defect. Changes in probing attachment level, probing pocket depths, and radiographic bone support were evaluated 12 months after removal of the membrane. Clinically and statistically significant improvements in outcome measurements were observed: a probing attachment level gain of 5.3 +/- 1.7 mm, a reduction in probing pocket depths of 6.1 +/- 2 mm, and an increase in the percentage of radiographic bone support of 31% +/- 18%. The results obtained were highly reproducible with 91.3% of the cases resulting in probing attachment level gains of 4 mm or more. The evidence provided in this investigation indicates that guided tissue regeneration can predictably increase the functional support, and possibly improve the prognosis of strategically important abutments. Guided tissue regeneration therapy should, therefore, be one of the options discussed in treatment planning for complex periodontal-prosthetic cases.

Adult↗
PubMed1995

Expression of the cutaneous lymphocyte antigen and the alpha IEL beta 7 integrin by intraepithelial lymphocytes in healthy and diseased human gingiva.

The presence of specific phenotypes of intraepithelial lymphocytes (IEL) was determined in healthy and diseased gingiva by immunohistochemistry. The cutaneous lymphocyte antigen (CLA) and the alpha IEL beta 7 integrin were detected with the HECA-452 and with the HML-1 monoclonal antibodies, respectively. Some 24-62% of CD3-positive intraepithelial lymphocytes expressed the CLA antigen in the junctional epithelium, while 49-54% expressed the alpha IEL beta 7 integrin. Similar results were obtained in the other gingival epithelia. The fraction of CLA-positive T cells and alpha IEL beta 7 integrin-positive T cells was significantly higher in the gingival epithelia than in the underlying connective tissue, indicating that the T-cell subsets defined by these surface adhesion molecules were selectively localized in the epithelial compartment. Comparison of the fractions of CLA-positive and alpha IEL beta 7 integrin-positive T cells across different disease groups did not show significant differences. The data indicate that intraepithelial lymphocytes expressing the CLA and the alpha IEL beta 7 phenotype are a quantitatively important component of gingival intraepithelial immunity. These adhesion molecules may play a part in the retention of specific T-cell subsets in gingival epithelia.

Adult↗
PubMed1995

Effect of cigarette smoking on periodontal healing following GTR in infrabony defects. A preliminary retrospective study.

This retrospective study examined the effect of cigarette smoking on the healing response following guided tissue regeneration (GTR) in deep infrabony defects. 71 defects in 51 patients underwent GTR with teflon membranes. 20 patients (32 defects) smoked more than 10 cigarettes per day, while 31 patients (39 defects) did not smoke. Clinical measurements were available at baseline, at membrane removal and at the 1-year follow-up. The oral hygiene of both groups was good, but smokers had significantly higher full-mouth plaque scores. No significant differences were observed between smokers and non-smokers in terms of % of tissue gained at membrane removal. At the 1-year follow-up, however, smokers gained significantly less probing attachment level than non-smokers (2.1 +/- 1.2 mm compared with 5.2 +/- 1.9 mm). A multivariate model, correcting for the oral hygiene level of the patients and the depth of the infrabony component, indicated that smoking was in itself a significant factor in determining the clinical outcome. A risk-assessment analysis indicated that smokers had a significantly greater risk than non-smokers to display a reduced probing attachment level gain following GTR. It is concluded that cigarette smoking is associated with a reduced healing response after GTR treatment, and may be responsible, at least in part, for the observed results.

Adolescent↗
PubMed1995

Compartmentalization of inflammatory cell phenotypes in normal gingiva and peri-implant keratinized mucosa.

The interpretation of studies aimed at understanding the pathophysiology of periodontal breakdown has been hampered by an insufficient understanding of the physiology of host responses in clinically healthy gingiva. This investigation was aimed at the evaluation of the in situ phenotype and topographic distribution of the inflammatory cells in clinically normal gingiva and peri-implant keratinized mucosa (PIKM). Soft tissue biopsies were obtained from clinically healthy gingiva or PIKM in 14 patients. Acetone fixed, cryostat sections were stained with a panel of monoclonal antibodies with a three stage avidin-biotin immunoperoxidase technique. Numbers of positive cells/mm2 were determined with a calibrated image analysis system. The major findings of the study were: (i) the presence of significantly higher densities of phenotypically characterized mononuclear cells in the ICT than in the JE in both gingiva and PIKM; (ii) the absence of a significant difference in PMN densities between JE and ICT in both gingiva and PIKM; (iii) the absence of statistically significant differences in densities of phenotypically characterized leukocytes associated with gingiva and PIKM; (iv) the presence of regional differences in the relative proportions of immunocompetent cells in both the gingiva and PIKM. It is concluded that inflammatory cells are selectively distributed in gingiva and PIKM. Unique functional compartments could be identified. The observed compartmentalization requires selective regulatory mechanisms.

B-Lymphocytes↗
PubMed1995

No detrimental effect of fibrin glue on the regeneration of intrabony defects. A controlled clinical trial.

This controlled clinical trial evaluated the potential of fibrin glue as a biological carrier to locally deliver guided tissue regeneration (GTR) modulators, 2 controlateral, morphologically similar defects were selected in each of 11 patients and randomly assigned to the test (teflon membrane and fibrin glue) and the control treatment (teflon membrane alone). Outcomes were assessed at membrane removal as newly formed granulation tissue and at the 1-year follow-up in terms of changes in probing attachment level, probing pocket depth, recession of the gingival margin, probing bone levels and percentage of fill of the intrabony defects. Data confirmed that GTR treatment of deep intrabony defects results in clinically and statistically significant improvements of the clinical parameters. No significant differences, however, were evidenced between the test and the control treatments. It is suggested that, since fibrin glue did not show detrimental effects on GTR, it could be applied as a biological carrier for the delivery of GTR enhancers into the surgical wound.

Adult↗
PubMed1995

Formation of normal gingival epithelial phenotypes around osseo-integrated oral implants in humans.

The oral, oral sulcular, and junctional epithelia of the natural gingiva each possess distinct patterns of differentiation that are demonstrable both ultrastructurally and by their individual patterns of macromolecular synthesis. The supracrestal tissues reformed around oral implants structurally resemble those of natural gingiva but little is known about phenotype changes occurring in the epithelia. To investigate whether peri-implant epithelia acquire similar patterns of differentiation to those of natural gingiva, biopsies from the supracrestal regions of five oral implants were examined by immunofluorescent methods using a panel of monoclonal antibodies with specificities for individual cytokeratins and ICAM-1, macromolecules which act as markers of the three gingival epithelial phenotypes. The observed staining patterns indicated the formation of oral, oral sulcular, and junctional epithelia which were phenotypically indistinguishable from those of natural gingival epithelia. This degree of reprogramming of epithelial gene expression is a surprising observation and the potential mechanisms leading to the development of those new epithelial phenotypes are discussed in the context of what is known about the development of natural gingiva, in terms of the possible effects of inflammation, and in relation to the known connective tissue influences on epithelial differentiation.

Cell Differentiation↗
PubMed1995

The modified papilla preservation technique. A new surgical approach for interproximal regenerative procedures.

A modification of the papilla preservation technique has been applied to achieve primary closure of the interproximal tissue over barrier membranes placed coronal to the alveolar crest. Fifteen patients with deep intrabony interproximal defects were treated. Defects had a probing attachment level loss of 9.9 +/- 3.2 mm and a recession of the gingival margin of 1.7 +/- 1.6 mm. The depth of the intrabony component was 5.5 +/- 2.9 mm; while the suprabony component was 5.9 +/- 2.0 mm. Titanium-reinforced teflon membranes were placed 1.3 +/- 0.7 mm from the cemento-enamel junction, 4.5 +/- 1.6 mm coronal to the interproximal alveolar bone crest. Primary closure over the interproximal portion of the membrane was obtained in 93% of cases. In 73% of the cases complete coverage of the membrane was maintained until its removal at 6 weeks. These data indicate that the modified papilla preservation technique can be successfully applied to obtain primary closure of the interdental space in regenerative procedures with barrier membranes.

Adult↗
PubMed1995

Interproximal free gingival grafts after membrane removal in guided tissue regeneration treatment of intrabony defects. A randomized controlled clinical trial.

The purpose of this controlled clinical trial was to compare the efficacy of two surgical approaches to protect the regenerated tissue following membrane removal in guided tissue regeneration (GTR) treated intrabony defects. Twenty-eight (28) defects, one each in 28 patients were randomly assigned after placement of the membrane to one of two treatment groups by blocking to prognostic variables. The test group received free gingival grafts on the interproximal regenerated tissue. In the control group the surgical flaps were coronally positioned over the regenerated tissue. The two groups were well balanced with respect to all prognostic variables. The results indicated that: 1) similar amounts of regenerated tissue were obtained in the two groups at membrane removal (7.6 +/- 2.8 mm, test; 8.3 +/- 2.3 mm, control); 2) a significantly greater amount of probing attachment level gain was observed in the test group (5.0 +/- 2.1 mm, test; 3.7 +/- 2.1 mm, control). This study indicated that placement of free gingival grafts on the interdental regenerated tissue further improves the clinical outcome of GTR in deep intrabony defects.

Adult↗
PubMed1995

Periodontal regeneration of human intrabony defects with titanium reinforced membranes. A controlled clinical trial.

The purpose of this controlled clinical trial was to compare the clinical efficacy of 3 treatment modalities in the treatment of deep interproximal intrabony defects. Forty-five (45) defects in 45 patients were randomly assigned to 1 of 3 treatment groups by blocking to prognostic variables. The test group was treated with titanium reinforced membranes positioned just apical to the cemento-enamel junction and the modified papilla preservation technique; the second group received conventional expanded polytetrafluoroethylene (ePTFE) barrier membranes applied at the alveolar crest; the third group was treated with an access flap procedure. The groups were well balanced with respect to all prognostic variables. During the 1-year observation period, patients were subjected to a stringent infection control program including: professional tooth cleaning every week for the first 6 weeks (all groups) and in the 4 weeks following membrane removal (guided tissue regeneration groups), then at monthly intervals (all groups). The results indicated that: 1) all treatment modalities resulted in clinical and statistically significant improvements in clinical attachment level (CAL) and probing depths (PD) at 1 year; 2) a significantly greater amount of CAL gain (P = 0.0003, analysis of variance) was observed in the test group (5.3 +/- 2.2 mm) with respect to both the ePTFE group (4.1 +/- 1.8 mm) and the flap control group 2.5 +/- 0.8; 3) in the test group the 1 year CAL (4.7 +/- 1.8 mm) was located more coronally than the baseline position of the interproximal alveolar crest (5.9 +/- 2 mm; P = 0.003, t test).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Vascular adhesion molecules and initial development of inflammation in clinically healthy human keratinized mucosa around teeth and osseointegrated implants.

Expression of vascular cell adhesion molecules (HEV-CAMs) by capillary loops represents an early step necessary for leukocyte extravasation and subsequent migration to sites of inflammation. The purpose of this investigation was to compare, the presence and distribution of ICAM-1, ELAM-1, VCAM-1 and PECAM-1 expression in the microvasculature of healthy gingiva and peri-implant keratinized mucosa. The selected HEV-CAMs were detected by a three stage immunoperoxidase technique in serial sections from clinically characterized sites. Biopsies were qualitatively and quantitatively analyzed. All biopsies displayed a small inflammatory infiltrate subjacent to the most coronal extension of the junctional epithelium. HEV-CAMs were expressed both in the sulcular and oral aspects of biopsies. Intensity of ICAM-1, ELAM-1 and VCAM-1 staining, however, was consistently higher in the region of the infiltrated connective tissue subjacent to the most coronal extension of the junctional epithelium. Only a fraction of microvascular loops were positive for ICAM-1, ELAM-1 or VCAM-1 when compared to the constitutively expressed PECAM-1. No significant differences were observed between gingiva and keratinized peri-implant mucosa. It was concluded that in healthy gingiva or peri-implant mucosa 1. HEV-CAM expressing capillary loops were in close topographic association with the inflammatory infiltrate; 2. only a fraction of capillary loops are activated to express ICAM-1, ELAM-1 and VCAM-1 at any given time; and 3. HEV-CAM expression in the periodontium may be influenced by local factors.

Antigens, Differentiation, Myelomonocytic↗
PubMed1994

Localized expression of mRNA for phagocyte-specific chemotactic cytokines in human periodontal infections.

In bacterial infections, mononuclear and polymorphonuclear phagocytes are key components of host defenses. Recent investigations have indicated that chemokines are able to recruit and activate phagocytes. In particular, interleukin-8 (IL-8) attracts polymorphonuclear leukocytes (PMNs), while monocyte chemoattractant protein-1 (MCP-1) is selective for cells of the monocyte/macrophage lineage. In this investigation, we analyzed the in situ expression of IL-8 and MCP-1 mRNAs in human periodontal infections. Specific mRNA was detected by in situ hybridization using 35S-labeled riboprobes in frozen tissue sections. Phagocytes (PMNs and macrophages) were specifically detected as elastase-positive or CD68+ cells by a three-stage immunoperoxidase technique. Results indicated that expression of phagocyte-specific cytokines was confined to selected tissue locations and, in general, paralleled phagocyte infiltration. In particular, IL-8 expression was maximal in the junctional epithelium adjacent to the infecting microorganisms; PMN infiltration was more prominent in the same area. MCP-1 was expressed in the chronic inflammatory infiltrate and along the basal layer of the oral epithelium. Cells of the monocyte/macrophage lineage were demonstrated to be present in the same areas. The observed expression pattern may be the most economic way to establish a cell-type-selective chemotactic gradient within the tissue that is able to effectively direct polymorphonuclear phagocyte migration toward the infecting microorganisms and modulate mononuclear phagocyte infiltration in the surrounding tissues. This process may optimize host defenses and contribute to containing leukocyte infiltration to the infected and inflamed area, thus limiting tissue damage.

Antigens, CD↗