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51.
Brambilla E Cagetti MG Fadini L Pariset P Strohmenger L Twetman S 《American journal of dentistry》2004,17(3):196-198
PURPOSE: To evaluate the salivary levels of chlorhexidine (CHX) after a single professional treatment with an antibacterial dental varnish (Cervitec) containing 1% CHX and 1% thymol. METHODS: Unstimulated whole saliva from 21 healthy young adults was collected at baseline and up to 24 hours after treatment at designated time intervals and the CHX levels in saliva were quantified with high-performance liquid chromatography. Post-treatment saliva samples were added to suspensions of mutans streptococci and supragingival dental plaque for a growth inhibition. RESULTS: CHX concentration in saliva showed a peak value (76.5 microg/ml) after 5 minutes followed by a slow decrease with time. The elevation was statistically significant (P < 0.05) up to 4 hours after the application of the varnish and the recorded values were back to baseline levels after 24 hours. The 2- and 4-hour post-treatment saliva samples inhibited growth of mutans streptococci by 46% and 33%, respectively. 相似文献
52.
Paolantonio M D'Angelo M Grassi RF Perinetti G Piccolomini R Pizzo G Annunziata M D'Archivio D D'Ercole S Nardi G Guida L 《Journal of periodontology》2008,79(2):271-282
BACKGROUND: The main therapeutic approach for periodontal diseases is mechanical treatment of root surfaces via scaling and root planing (SRP). Multicenter clinical trials have demonstrated that the adjunctive use of a chlorhexidine (CHX) chip is effective in improving clinical results compared to SRP alone. However, some recent studies failed to confirm these clinical results, and conflicting results were reported regarding the effects of the CHX chip on subgingival microflora. The aim of this study was to provide further data on the clinical and microbiologic effects of CHX chips when used as an adjunct to SRP. METHODS: A total of 116 systemically healthy individuals with moderate to advanced periodontitis, aged 33 to 65 years, were recruited from the Departments of Periodontology of four Italian universities. For each subject, two experimental sites were chosen that had probing depths (PD) > or =5 mm and bleeding on probing (BOP) and were located in two symmetric quadrants. These two sites were randomized at the split-mouth level, with one receiving SRP treatment alone and the other receiving treatment with SRP plus one CHX chip (SRP + CHX). PD, relative attachment level (RAL), and BOP were evaluated at baseline, prior to any treatment, and after 3 and 6 months. Supragingival plaque and the modified gingival index were evaluated at baseline and after 15 days and 1, 3, and 6 months. Subgingival microbiologic samples were harvested at baseline and after 15 days and 1, 3, and 6 months, cultured for total bacterial counts (TBCs), and investigated by polymerase chain reaction analysis for the identification of eight putative periodontopathogens. RESULTS: When all of the pockets were considered, the PD and RAL were significantly less at 3 and 6 months compared to the baseline scores (P <0.01) for both treatments. Moreover, the PD was reduced in the SRP + CHX treatment group compared to the SRP treatment group at 3 and 6 months, whereas the RAL was similar for both treatments at 3 months and was reduced in the SRP + CHX treatment group at 6 months. The differences in PD reductions between the treatments were 0.30 and 0.55 mm at 3 and 6 months, respectively (P <0.01); for the RAL gain, the differences were 0.28 and 0.64 mm, respectively (P <0.001). The TBCs decreased significantly with both treatments. A similar, although less evident, pattern was noted when only the pockets with an initial PD > or =7 mm were considered. The percentage of sites positive for BOP was similar between the treatments at each time point. At 15 days and 1 month, the TBC for the SRP + CHX treatment group was significantly lower than for the SRP treatment group (P <0.01 and P <0.05, respectively). Over time, both treatments generally reduced the percentages of sites positive for the eight putative periodontopathic bacteria, although greater reductions were seen often for the SRP + CHX treatment group. CONCLUSIONS: The adjunctive use of the CHX chip resulted in a significant PD reduction and a clinical attachment gain compared to SRP alone. These results were concomitant with a significant benefit of SRP + CHX treatment on the subgingival microbiota. 相似文献
53.
This study evaluated the shear bond strength, failure modes, and confocal microscopy of two different amalgam alloy restorations lined with five adhesive systems. Two regular-set high-copper dental amalgam alloys, Amalcap Plus and Valiant Ph.D, and five commercially available adhesive systems were selected. One hundred and twenty freshly-extracted human third molars were used for the study. The results were statistically evaluated using two-factor analysis of variance (ANOVA). The shear bond strength (SBS) of amalgam to dentin was significantly affected by both the adhesive (p<0.0001) and amalgam alloy (p<0.0002). Regarding mode of failure (MF), among samples restored with Valiant Ph.D, 31 of 50 exhibited adhesive failure, and 19 displayed mixed failure. Laser optical microscopy (OM) of the bonded interface revealed the presence of a good hybrid layer was evident in all experimental groups. Higher bond strengths were measured for four of the five adhesives when used in combination with the spherical alloy. 相似文献
54.
Introduction
The aim of this study was to determine in anterior teeth, bicuspids, and molars (1) the accuracy of 3 different electronic apex locators (EALs) in detecting the apical foramen and (2) the accuracy of digital radiography in determining the working length (WL), compared with visible control under a microscope.Methods
By using radiovideography (RVG), we measured the lengths of 120 root canals with 3 different EALs (Endex, ProPex II, and Root ZX) and compared them with the actual lengths. The accuracy of EALs and RVG was related to each dental category. An endodontic training kit (Pro-Train) was used during experimental procedures.Results
Statistical analysis showed that the 3 EALs and RVG were less accurate in anterior teeth and molars than in bicuspids. The paired-sample t test showed no statistically significant difference between mesiodistal plane and buccolingual plane digital radiography in all groups.Conclusions
The 3 EALs tested were more accurate in detecting the apical foramen in bicuspids than in both molars and anterior teeth. Radiographic measurements were not reliable for determining WL in all dental groups in both radiographic planes. 相似文献55.
Nibali L Griffiths GS Donos N Parkar M D'Aiuto F Tonetti MS Brett PM 《Journal of clinical periodontology》2008,35(3):193-198
Background: Interleukin‐6 (IL‐6) polymorphisms have been shown to affect IL‐6 promoter activity. This study investigated the possible role of IL‐6 genetic polymorphisms and haplotypes in the predisposition to aggressive periodontitis (AgP). Material and Methods: A case–control association study on 224 AgP patients and 231 healthy controls was performed in order to detect differences in genotype distributions of five single nucleotide polymorphisms (SNPs) located in the promoter region of the IL‐6 gene. Results: The IL‐6 ?1363 polymorphism was associated with a diagnosis of AgP in subjects of all ethnicities (p=0.006, adjusted logistic regression). The ?1480 SNP was associated with LAgP in subjects of all ethnicities (p=0.003). The ?1480 and ?6106 polymorphisms were associated with Localized AgP in Caucasians (n=24) (p=0.007 and 0.010, respectively). Haplotypes determined by the ?1363 and ?1480 polymorphisms were also associated with LAgP (p=0.001) in Caucasians. Conclusions: This study supports the hypothesis of a link between IL‐6 genetic factors and AgP and highlights the importance of two IL‐6 polymorphisms (?1363 and ?1480) in modulating disease phenotype and susceptibility. 相似文献
56.
Severe panfacial fracture with facial explosion: integrated and multistaged reconstructive procedures 总被引:4,自引:0,他引:4
Midface fractures, especially if related to traffic accidents, represent a remarkable problem from a surgical, psychological, and social standpoint. In trauma dynamics, the pattern of the fractures can extend to all bony fragments and is often associated with soft tissue injuries and loss of bony structures. This can lead to posttraumatic deformities that greatly influence the patient psychologically and limit his social rehabilitation, sometimes permanently. Panfacial trauma includes midface fractures associated with fractures of other areas (i.e., mandible, frontal bone). Orbits and the nasoethmoidal area are often involved with loss of soft tissue and, in severe cases, loss of orbital contents. We report an unusual complex clinical case representative of this kind of pathological profile in which the guidelines described in the literature were followed in the reconstructive procedure. 相似文献
57.
Trombelli L Annunziata M Belardo S Farina R Scabbia A Guida L 《Journal of clinical periodontology》2006,33(1):69-75
AIM: The purpose of the present study was to investigate the effectiveness of a regenerative procedure based on supra-crestal soft tissue preservation in association with combined autogenous bone (AB) graft/enamel matrix derivative (EMD) application in the treatment of deep periodontal intra-osseous defects. METHODS: Thirteen consecutively treated patients, seven females and six males, aged 30-65 years, three smokers, were included. A total of 15 deep, one- to two-wall intra-osseous defects were selected. Immediately before surgery and 6 months after surgery, pocket probing depth (PPD), clinical attachment level (CAL), and gingival recession (REC) were recorded. RESULTS: PPD amounted to 9.4+/-1.8 mm before surgery, and decreased to 4.7+/-1.2 mm post-surgery (p<0.0000). CAL varied from 10.5+/-2.0 mm pre-surgery to 6.2+/-1.7 mm post-surgery (p<0.0000), with CAL gain averaging 4.3+/-1.4 mm. Fourteen (93.3%) defects presented CAL gain >/=3 mm. REC change was 0.4+/-0.7 mm. CONCLUSIONS: Results from the present study indicated that a regenerative procedure based on supra-crestal soft tissue preservation and combined AB/EMD treatment leads to a clinically and statistically significant improvement of soft tissue conditions of deep periodontal intra-osseous defects. 相似文献
58.
BACKGROUND: Teeth with a palatal groove often present with severe localized periodontal attachment loss including pocket formation and alveolar bone loss. The aim of the present case report was to describe the regenerative surgical treatment of periodontal and bone lesions associated with the subgingival extension of a palatal groove affecting a maxillary lateral incisor. METHODS: The left maxillary lateral incisor of a systemically healthy young subject presented with a palatal probing depth of 10 mm with no gingival recession at the buccal and palatal surfaces; the neighboring interdental papillae were intact. The radiograph showed a radiolucency area distal to the affected tooth. Treatment procedures consisted of: 1) the papilla amplification flap with the use of enamel matrix proteins as the regenerative periodontal material; 2) the elimination/flattening of the radicular portion of the palatal groove; and 3) the sealing of the coronal portion of the groove with composite flow. RESULTS: The clinical examination at 1 year revealed a clinical attachment gain (8 mm) with a shallow residual probing depth (2 mm) and no increase in gingival recession. The radiographic examination showed the complete disappearance of the radiolucency area suggesting bone fill. CONCLUSIONS: The present study indicated that localized periodontal defects associated with a palatal groove can be successfully treated by means of the papilla amplification flap with the use of enamel matrix protein as the regenerative material. The long-term stability of such successful results needs to be determined. 相似文献
59.
Checchi L Mele M Checchi V Zucchelli G 《The International journal of periodontics & restorative dentistry》2008,28(4):367-373
This case report evaluated the long-term effects of osseous resective therapy in the treatment of a patient with moderately advanced periodontal disease. In 1984, the patient underwent initial therapy followed by a periodontal surgical phase consisting of osseous recontouring with an apically positioned flap. After 20 years, in 2003, the patient presented with a traumatic complication. An exploratory surgery revealed a fracture on the roof of the pulp chamber on the maxillary left first molar. The buccal roots were resected, preserving the palatal root, and a reevaluation of the long-term outcome of osseous resective surgery was performed. It is suggested that the positive treatment result is the consequence of the reestablishment of tissue morphology favorable for oral hygiene and plaque control by the patient. 相似文献
60.
AIM: The aim of this study was to characterize the gingival inflammatory response to de novo plaque accumulation in subjects treated for aggressive periodontitis (AP). The gingival inflammatory response of the AP subjects was retrospectively compared with that of periodontally healthy individuals (PH) matched for exposure to plaque and of periodontally healthy subjects previously identified as "high responders" (HR) and "low responders" (LR). MATERIALS AND METHODS: 13 AP subjects and 26 matched PH subjects participated in a 21-day experimental gingivitis trial. Plaque index (PlI), Gingival index (GI), gingival crevicular fluid volume (GCF) and angulated bleeding score (AngBS) were recorded at days 0, 7, 14 and 21. Cumulative plaque exposure (CPE), i.e. PlI over time, was also calculated. RESULTS: GCF was significantly higher in AP compared with PH group at each observation interval (p< or =0.001). In addition, GCF was significantly higher in AP group compared with either LR or HR groups at each observation interval (p<0.001). CONCLUSIONS: These results suggest that susceptibility to gingival inflammation in response to de novo plaque accumulation may be related to susceptibility to periodontitis. 相似文献