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D Landi

Publications and source records attributed to D Landi.

6 recordsLinked to original sources
PubMed2003

[Bonding compatibility between adhesive systems and composite resins].

AIM: The purpose of the present study was to analyse bonding compatibility between photo- and self-polymerising composite resins ad two-step total-etch (one component) adhesive systems with a different activation method. METHODS: Thirty healthy extracted molars were cut transversally to obtain sixty flat dentin surfaces. The acid conditioned surfaces were bonded with Scotchbond 1 (3M), Excite (Vivadent) or Excite DSC (Vivadent). A cylinder of composite resin (3 mm diameter and 4 mm height) was constructed on each adhesive layer using photopolymerised Tetric Ceram (Vivadend) and dual Luxacore (DMG) but activated only chemically. The samples were subjected to the shear bond test. The fracture surfaces obtained were classified by type and site in the stereomicroscope. Twelve samples representing each group were further prepared for the SEM. RESULTS: The data obtained from the test, the microscopic investigation and statistical analysis (ANOVA and Bonferroni) seem to confirm the presence of a reduced bonding compatibility between one-component adhesive systems and self-polymerising composites. This incompatibility is evident for the adhesive Scotchbond 1 and limited for Excite, while it seems to be overcome by Excite DSC which appears to bond well with both Tetric Ceram and Luxacore. CONCLUSIONS: Adhesive-composite incompatibility seems to depend on the activation method of the composite as well as on that of the adhesive system. The chemical compatibility bet-ween these two materials is influenced not only by the chemical composition of the adhesive, but also by that of the composite.

Acrylic Resins↗
PubMed1986

Estrogen receptor content in breast cancer: correlation between biochemical and immunohistochemical methods.

Estrogen receptor content of 26 consecutive cases of ductal breast carcinoma was evaluated by using both biochemical and immunohistochemical methods. Agreement was present in 20/26 cases (76.9%). The analysis of discordant cases shows that in 5 cases disagreement is due to sampling error or to prolonged storage before biochemical evaluation. Such cases may reasonably be excluded when correlating results. Linear regression of the remaining 21 cases shows a significant relationship (r = 0.931; p less than 0.001) between biochemical and immunohistochemical values. Results show that immunohistochemical and biochemical assays are largely comparable, and stress the important role of the pathologist in tumor sampling.

Adult↗
PubMedDate not supplied

[Sclerotic dentin: aetio-pathogenetic hypotheses].

The situation with regard to current knowledge concerning dentinal sclerosis is examined. SEM and TEM examination of specimens of sclerotic dentin showed changes in diameter and tubular content leading to various degrees of obstruction of the lumen. There is agreement that this is due to the neo-apposition of peri-tubular dentin associated with intra-tubular deposition of crystals of Whitelockite, although the debate is still open on how such deposition may come about. Sclerotic casts are created in the tubules that may completely occlude the lumen or present a central cavity. In general these casts are surrounded by a thin fissure that has been variously interpreted. Many agree that sclerotic dentin has an increased mineral component, but without clarifying whether this is only a quantitative increase or whether it is also due to hyper-mineralisation of pre-existing dentin. An examination of the literature reveals numerous hypotheses surrounding the genesis of sclerotic dentin: some say it is due to passive phenomena of dissolution and precipitation whereas others suggest active involvement of the odontoblastic processes and the pulp. Since no studies have confirmed or confuted these theses, we may continue to think of dentinal sclerosis as a multifactorial event, due both to an increase in the thickness of peri-tubular dentin and to intra-tubular precipitation of calcium salts associated with mineralisation of the organic structures present in the lumen.

Calcium Phosphates↗