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Biomedical subjects

D Cicciù

Publications and source records attributed to D Cicciù.

At least 19 recordsLinked to original sources
PubMed2006

Mechanical behavior of quartz fiber reinforced epoxy resins for teeth restoration.

In this work composite materials, based on quartz fibers and epoxy resins, were employed with the aim to restore damaged teeth. The composite materials were chosen because they show biomechanical features very similar to that of the dentine, the main constituent of the tooth. Extracted teeth were rebuilt with two different restorative procedures: in the first, the composite material was pre-formed in a conical trunk shape abutment (PA) and then bonded to a fiber quartz post with a dental bonder. In the second rebuilt system the abutment was prepared by cross linking the resin on the fiber quartz post with a halogen lamp (CRA). The restored teeth were then mechanically tested and observed with a Scanning Electron Microscope (SEM) with the aim to study the interaction between the reconstructive materials. Wetting and roughness measurements were also carried out in order to study the interface adhesion between the post and the abutments. Characterization analysis evidenced that the CRA restorative procedure improves the adhesion between the substitutive materials and shows higher fracture strength than the PA ones. Anyway both the rebuilt systems are able to support the masticator load. An explanation of the interfacial post-abutment interaction phenomenon is discussed.

Adhesiveness↗
PubMed2004

Polyamines in nickel-titanium archwire-induced gingivitis in adolescents.

BACKGROUND: Polyamines spermine, spermidine, and putrescine are involved in a number of inflammatory diseases, but their role in the development of gingivitis and periodontitis has not been fully investigated. The goal of this investigation was to study the levels and the variations of these amines, and the main enzymes related to their metabolism, during archwire orthodontic treatment, a condition which may induce gingivitis. METHODS: Sixty patients (age range: 11 to 27 years) were examined for gingivitis occurring during nickel-titanium (Ni-Ti) archwire orthodontic treatment. Plaque and gingival indexes (PI, GI) as well as salivary polyamine metabolism before the archwire insertion (T0) and at 3 (T1), 6 (T2), and 12 (T3) months of treatment were measured. RESULTS: In patients in the age range of 14 to 17 years, spermine and spermidine, but not putrescine contents, as well as ornithine-decarboxylase (ODC) and S-adenosylmethionine-decarboxylase (SAMDC) activities, significantly rose at 3 months after insertion, without any change in periodontal parameters, and further increased at 6 months reaching the maximum at 12 months. GI increased later, from 6 to 12 months, while PI did not significantly change. Spermidine/spermine-N1-acetyltransferase (SSAT) activity remained unchanged from T0 to T3. On the contrary, in patients whose age was 11 to 13 or over 18 years, no significant variations in polyamine metabolism and periododontal parameters were observed at any examination time. CONCLUSION: These data support the hypothesis that salivary polyamines might be earlier indicators of gingivitis than the gingival index score in adolescents wearing archwire appliances.

Acetyltransferases↗
PubMed2002

Age-related salivary polyamine increase in adolescents wearing orthodontic Ni-Ti archwires.

Until now information about the influence of puberty on gingival tissue responses to Ni-Ti alloy haven't been available. Since our previous researches have demonstrated that Ni-Ti appliances have an influence on hyperplastic gingivopathy and data has pointed out a possible hormonal influence on the susceptibility of gingival tissue to mechanical stress, we have attempted to study the relationship between fertility hormones and the periodontal response to Ni-Ti appliances. Three groups, ranging from 6 to 17 years old, were tested for salivary polyamine concentrations and for fertility hormone levels 12 months after Ni-Ti application. Results obtained from Pearson's correlation coefficient between polyamine and sexual hormone concentrations, as well as gingival and plaque indexes, suggest that the adolescent gingival tissue undergoes an hyperplastic process after long-term use of Ni-Ti appliances in relation to the puberty age-restricted peak of fertility hormones.

Adolescent↗
PubMed1996

[An XPS and SEM study of the chemical-micromorphological characteristics of the dentin-resin adhesive interface. I].

In this preliminary note the author examined the chemical characterisation of dentin surfaces after treatment with an acid conditioner (nitric acid), using the XPS and Auger techniques, to evaluate whether micromorphological variations already reported by other authors are associated with changes of a chemical nature. The results of this study show an alteration of the superficial chemical component of dentin following treatment with the conditioner that would enable the realisation of closer binding with composite materials.

Acid Etching, Dental↗
PubMedDate not supplied

A comparison of nimesulide beta cyclodextrin and nimesulide in postoperative dental pain.

The aim of this study was to assess the efficacy and tolerability of single doses of nimesulide beta cyclodextrin compared with nimesulide in patients with dental pain following surgical procedures. This was a randomised, double-blind, between-patient, multicentre study involving 148 outpatients suffering from moderate to severe pain, who received single doses of either 400 mg nimesulide beta cyclodextrin or 100 mg nimesulide. The principal criterion for efficacy was pain intensity assessed on a visual analogue scale (VAS) 15 minutes after drug intake. Pain intensity was further evaluated 30, 45, 90, 120, 180, 240 and 360 minutes after dosing. Pain relief was evaluated at the same time points by means of a categorical scale. The time point of first pain relief, the use of rescue medication and the global evaluation of efficacy were also recorded. The reduction in pain intensity was significantly more pronounced in the nimesulide beta cyclodextrin group at 15, 30, 45 and 60 minutes (p < 0.01). Pain relief was significantly greater (p < 0.05) and more rapid with nimesulide beta cyclodextrin. In the patient overall assessment of efficacy, nimesulide beta cyclodextrin and nimesulide were rated excellent or good by 95% and 92% respectively; only one patient in the nimesulide beta cyclodextrin group needed rescue medication. Both study drugs were effective and well tolerated in the treatment of acute dental pain, with nimesulide beta cyclodextrin showing a faster onset of analgesic action.

Adolescent↗
PubMedDate not supplied

The ameloblast movement in rat incisor. L.M., S.E.M. and C.L.S.M. study.

The internal epithelium of enamel organ and the below enamel surface during growth of the lower incisor, were examinated in ten Wistar rat 12-27 weeks old and weighing between 150/200 gr, by means of immuno histochemical, light and scanning electron microscopy techniques. Our specimens indicate that during the outer enamel secretion the anti-actin positivity goes from distal terminal web to infra nuclear region of cell body. The results of the present study do not support the active movement hypothesis, conversely they support the Warshawsky (1992) hypothesis, i.e. the distal terminal web permits the maintenance and the assembling of ameloblasts during enamel growth. Hence we do agree with Osborn (1970) who reported that, during secretion, ameloblasts move passively in response to secretory forces.

Ameloblasts↗
PubMedDate not supplied

Kinesiographic investigations in children with increased nasal airways resistance.

The aim of this study is to evaluate by means of the kinesiographic test, how the muscular alteration, linked with mouth breathing, modifies mandibular dynamics. From a sample of children aged between 8-11 years, on the basis of increased nasal airways resistance measured with the forced oscillation technique, we selected a group of 14 subjects. These children underwent kinesiographic examination (K-System Biotronic) and they were compared to a control group. Certainly, the speeds reduction in the pathological group emerged as the most significant data. The mastication tracings on the frontal plane, in the group with increased nasal airways resistance, moreover appeared to be reduced in width, elongated in shape and sometimes irregularly square, compared to the bell shape typical of subjects without any dysfunctional pathologies. Considering that each subject responds in a personal manner to an increase of the nasal resistances, due to the extremely variable individual adaptability, the kinesiographic test, together with the electromyographic one, in our opinion, can assist anamnesis, clinical examination and other instrumental investigations, in the identification of those subjects in which the increase of the nasal airways resistance interferes with muscular function, laying the basis for possible modifications in the craniofacial growth.

Adaptation, Physiological↗
PubMedDate not supplied

[Use of G.I.C. as a cavity liner. Clinical experience].

The authors have examined the effects of the C.V.I. used as liners in the V Black classes in fillings made by restorative material on the right-hand dental maxillary arch of five patients, comparing them to the left-hand dental maxillary arch on some subjects affected by the some lesions and filled with the some procedure but using as liner a calcium hydroxide material submitting the all treated teeth to a sensitivity tests. On the basis of such clinical experience the Authors conclude that the use of the C.V.I. as liner shows, compared to the calcium hydroxide, the characteristic to be chemically bonded to the dentin and mechanically through the eching to the composite restorative material as well as the bio-mimetic characteristic property towards the dentin.

Adhesiveness↗
PubMedDate not supplied

[Use of the Maryland bridge in periodontology].

The authors have reported the investigations about the Maryland Bridge and its importance in periodontology. The Authors have suggested the clinical application of this kind of prosthesis and the Authors have reported about two clinical cases that have had first a periodontal treatment then a Maryland Bridge prosthesis.

Acid Etching, Dental↗