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M Gagliani

Publications and source records attributed to M Gagliani.

15 recordsLinked to original sources
PubMed2006

Stress distribution in a post-restored tooth using the three-dimensional finite element method.

Clinicians are opting ever more frequently for restorative materials which have an elastic modulus similar to that of dentin when reconstructing endodontically treated teeth. Metallic posts, which are capable of causing dangerous and non-homogenous stresses in root dentin, are slowly being abandoned. Ideal posts may be those made of various types of fibre (carbon, mineral and glass) and which are adhesively luted into the canal. Among the different methods for evaluating the mechanical behaviour of posts in root canals (progressive loads and photo-elastic technique) the finite element method (FEM) presents many advantages. The aim of this paper is to evaluate, utilizing three-dimensional analysis of the finite elements, what the effect of material rigidity, depth of insertion and post diameter could be on the stress distribution in the different components of the single tooth-post-core reconstruction unit. The results of the FEM analyses, expressed as the distribution of Von Mises stress values, has allowed us to conclude that (i) fibreglass-reinforced composite distributes stress better than titanium alloy or stainless steel; (ii) fibreglass-reinforced composite posts should be inserted as deeply as possible (but maintaining 5-6 mm of gutta-percha apical seal); (iii) fibreglass-reinforced composite post diameter does not affect stress distribution, therefore, as much radicular dentin as possible should be preserved.

Compressive Strength↗
PubMed2003

Periapical endodontic surgery: a 3-year follow-up study.

AIM: To monitor the outcome of periradicular surgery in a group of teeth treated with microsurgical technology and ultrasonic root-end preparation. METHODOLOGY: One hundred and twenty-eight teeth with failed conventional root canal treatment were included. The surgical procedure was completed using ultrasonic retrotips and a zinc oxide-EBA (Super Seal, Ogna Pharmaceuticals. Milan, Italy)-reinforced material was used to seal the root end cavities. Lesions were examined radiologically at 1. 3. 6. 12, 24 and 36-month intervals. Radiographs were independently analysed according to a previously published classification. RESULTS: Eight teeth were extracted due to fracture or perforations undetected radiologically: these cases were excluded from the study. Of the 120 teeth examined. the overall success rate was 92.5%; 94 healed with complete bone filling of the surgical cavity, 17 were considered to have healed by apical scar formation, four demonstrated uncertain healing and five were considered failures. Eighty of 120 teeth examined had successfully healed from a radiological point of view within 12 months. No differences in outcome occurred between anterior, premolar and molar teeth. Although all failures occurred in teeth with posts, no statistically significant difference was noted (Mann-Whitney U-test, P = 0.37). CONCLUSION: Modern surgical endodontic procedures associated and ERA (Super Seal, Ogna Pharmaceuticals, Milan, Italy) root end fillings were successful over 3 years in 92.5% of cases.

Adolescent↗
PubMed1998

Ultrasonic root-end preparation: influence of cutting angle on the apical seal.

Apical resection is fundamental in obtaining a correct apical seal. The purpose of this study was to evaluate how the apical root resection angle and the cavity made by ultrasonic retrotips may influence the apical seal. A total of 48 extracted teeth were endodontically treated and sealed by guttapercha vertical compaction: 24 were resected with a 45 degrees angle and 24 with a 90 degrees one. An ultrasound source (P.M. 400 EMS) and a CT5 Scaler were used to make the retrograde cavity that was filled afterwards with EBA-zinc oxide-eugenol alumina-added cement. Apical leakage was determined using fuchsin and assessed after the roots were sectioned longitudinally. Linear dye penetration in dentin and at the interface between dentin and cement was measured with a stereomicroscope (x 12 magnification), and the results were statistically analyzed. Results showed that there was less infiltration both in dentin and in the space between the filling and the dentinal wall in the group with the 90 degrees angle, but this difference was statistically significant (p < 0.0001) only for the dentin. None of the samples showed leakage greater than the depth of the preparation. An apical cavity of 3 mm or more along the vertical axis can produce a safe and effective seal.

Bicuspid↗
PubMed1998

Caries prevention during pregnancy: results of a 30-month study.

The purpose of this 30-month study was to explore the effectiveness of a caries-preventive regimen in lowering the salivary mutans streptococci level in pregnant women and, subsequently, in inhibiting the growth of these bacteria in their young children. Beginning at the end of the sixth month of pregnancy and continuing until delivery, subjects rinsed daily with 0.05 percent sodium fluoride and 0.12 percent chlorhexidine. The authors monitored the salivary mutans streptococci levels during the last six months of pregnancy and every six months thereafter for 24 months. They also measured bacterial levels in the children every six months until they reached age 24 months. The results show that treatment significantly reduced salivary mutans streptococci levels in mothers and delayed the colonization of bacteria in their children for about four months.

Analysis of Variance↗
PubMed1998

[Computer-assisted image postprocessing in intraoral digital radiography].

INTRODUCTION: Computer-assisted postprocessing was performed on selected digital dental radiographs using a professional software for photographic retouching. MATERIALS AND METHODS: The optical characteristics of 22 digital intraoral images (radio-videographies) taken on 18 patients were modified as regards their density and contrast values. Three different kinds of densitometric curves, corresponding to particular changes in post-processing parameters, were preliminary defined as the most effective for the demonstration of root canals and of alveolar bone. They were then applied to each X-ray image and the pictures thus modified were subsequently printed and read on a blind basis by three observers who considered the conspicuity of each structure of interest (root canals and alveolar bone). RESULTS: The results, submitted to statistical analysis, demonstrate that computer-assisted postprocessing can improve the visual yield and the diagnostic effectiveness of digital dental images in 67% of cases for the periapical bone and in 86% of cases for the root canals. CONCLUSIONS: The most effective sets of post-processing parameters established for each structure of interest are proposed together with a pre-programmed function to be introduced into the software of digital radiographic equipments.

Adolescent↗
PubMed1997

The effect of biannual applications of amine fluoride solution on caries incidence in permanent first molars: a 5-year study.

A randomized double-blind clinical trial was undertaken in a non-fluoridated community to assess the effectiveness of a minimal preventive intervention based on biannual applications of an amine fluoride (AmF) solution containing 1% fluoride. A total of 284 schoolchildren aged 6 years were recruited from a primary school in Milan, Italy, and randomly assigned to an experimental or a control group. The subjects of the experimental group received two applications each year of AmF to the permanent first molars and the control group subjects received similar applications of a placebo solution. Both in the experimental and control groups caries experience (DMFT) of the first molars was recorded every 6 months for 5 years. The mean DMFT scores in the experimental and control group were, respectively, 0.56 and 0.22 at the beginning and 1.14 and 1.75 at the end of the study. The preventive effect of the treatment became statistically significant only after 3 years. Survival analysis performed on the first molars that were sound at baseline showed that the topical AmF treatment caused, after 5 years, a significant reduction of caries incidence. This result confirms observations found in the international literature on the anticaries action of AmF. The administration rate used in this study seems to be useful for community preventive applications as it reduces the total amount of fluoride administered and the potential risks, and involves few personnel.

Cariostatic Agents↗
PubMed1996

[The measurement parameters in dental radiography: a comparison between traditional and digital technics].

Digital and conventional techniques for dental, panoramic and intraoral radiography, were compared to assess measurement accuracy. The study was carried out on two plastic models of maxillary and mandibular arches, each containing 14 teeth extracted and positioned in their anatomical site. The teeth were prepared by opening the pulpal cavity and inserting endodontic wires within the canals. Intraoral x-ray images were taken with long-cone technique using a commercial high-resolution film and with a charge coupled device (CCD) sensor (radiovisiography). The models were then submitted to panoramic tomography with photostimulable phosphor plates. The length of the canals was measured on each image and compared to the length of the inserted wires. For the digital pictures, the measurement was performed directly on the monitor with the aid of electronic calipers. Magnification averages 3.40%, 9.47% and 14.11% for anterior teeth in intraoral radiography, in radiovisiography and panoramic radiography, respectively. The results demonstrate the presence of some degree of magnification for every radiographic procedure. This effect becomes statistically significant for both radiovisiography and digital panoramic techniques, especially in the latter. In spite of their well-known practical and dosimetric advantages, digital techniques in dental radiology must be used carefully whenever a reliable measurement is required.

Analysis of Variance↗
PubMed1996

[Digital radiology in dentistry: experience with direct intraoral techniques (radiovideography)].

The aim of this paper was to discuss the techniques for intraoral digital radiography (radiovisiography) and to compare their accuracy in dental radiographical diagnosis. Emphasis was given to their potential applications in oral radiology. Radiovisiography was compared with intraoral films and electronic magnifications from digital panoramic radiographs in 38 patients, for a total amount of 36 caries, 27 periapical conditions and 58 metal implants. Moreover, the accuracy of the measurements made with the three techniques was assessed on a specimen of mandibular and maxillary arches containing 28 extracted teeth with endodontic files of known length. Radiovisiography was as effective as intraoral films and more effective than digital panoramic radiographs in the diagnosis of caries and periapical lesions. Nevertheless, it produced a significant magnification and yielded unreliable measurements of root canals and metal implants. Radiovisiography is very easy to use and does not require dark room procedures nor chemicals of any kind. In addition, it reduces patient's X-ray exposure by over 50% with respect to film studies. For these reasons, this technique seems to be worthy of widespread use in dental radiography, with the exception of the conditions requiring an exact measurement of working length.

Adult↗
PubMed1990

["Canal Finder System" verification in vitro and in vivo].

Many Authors investigated about the way of cleaning the root canal, using chemo-mechanical instruments. "Canal Finder System" too have been reported, both in in vitro and in vivo experiments, to be a proper method in endodontic treatments. We studied, in our past experiments, the real capacity of cleaning from dentinal debris the root canal and the wear of the instruments we use with CFS. At last we used CFS in patients and we agree with the other that, in the preparation of the apex it can't be use without associating it with manual instruments.

Dental Cavity Preparation↗
PubMedDate not supplied

Caries-preventive effect of topical amine fluoride in children with high and low salivary levels of mutans streptococci.

The aim of the study was to assess the relationship between the salivary mutans streptococci (SMS) level and the effectiveness of a preventive intervention based on a biannual application of an amine fluoride solution (AmF). A total of 284 schoolchildren aged 6 years were recruited from eleven classes of a primary school in Milan and randomly assigned to an experimental (A) and a control group (B). SMS counts were obtained at baseline and caries incidence data (diseased, missing, filled teeth, DMFT) were recorded every 6 months for 5 years. The participants of the experimental group received application of an AmF 1% F(-) solution twice a year on the enamel surfaces of the first permanent molars for 5 years. Control group subjects received application of a placebo solution twice a year on the enamel surfaces of the first molars for the same period. The mean DMFT in the experimental and control groups were 0.56 and 0.22, respectively, at the beginning and 1.14 and 2.06 after 5 years. SMS data allowed children to be classified into low- (0-10(5) CFU/ml of saliva) and high- (>10(5) CFU/ml of saliva) SMS subjects. Survival analysis, performed on the first molar data split by SMS group, showed a significantly higher caries reduction in low-SMS experimental group subjects compared to low-SMS control group subjects after 5 years. No significant differences were found between the two high-SMS experimental and control groups. These findings indicate that the preventive effects of the treatment were significantly lower in subjects who had high SMS. It is concluded that the effectiveness of a simple and economical topical fluoride intervention applicable at a community level is significantly influenced by the SMS level of the subjects involved. Simple AmF preventive interventions, applied on low-SMS subjects, can give significant results in terms of caries reduction.

Administration, Topical↗