Hard and soft tissue responses to three different implant materials in a dog model.

The aim of this study was to assess hard and soft tissue responses using three dental implants made of different materials. Implants made of titanium (Ti), yttria-stabilized tetragonal zirconia polycrystals (Y-TZP) and ceria partially stabilized zirconia/alumina nanocomposite (Ce-TZP/Al2O3) were used in a dog model. Five male beagles were sacrificed at three months after implantation, and harvested mandible were observed and analyzed. Histological observations were similar in all groups. There were no significant differences in any histomorphometric parameters. Our results suggested the possibility of Ce-TZP/Al2O3 as a dental implant material, similar to Ti and Y-TZP.

Reparo em resina composta - efeito do condicionamento ácido e dos sistemas adesivos / Composite resin repair - effect of acid etching and adhesive systems

O objetivo deste trabalho foi avaliar o efeito do condicionamento ácido e do tipo de adesivo sobre a resistência de união de reparos em compósitos tratados com jato de óxido de alumínio. Foram confeccionados 60 discos com compósito, cor A2 (Filtek Z350 - 3M ESPE®), envelhecidos por seis meses em água. Após o polimento, as superfícies foram submetidas ao jato de óxido de alumínio (45 -jm) e distribuídas em seis grupos com dez espécimes cada um: G1: Adper Scotchbond Multi-Purpose (3M ESPE®), sem condicionamento ácido e sem "primer"; G2: Adper Scotchbond Multi-Purpose (3M ESPE®), após condicionamento com ácido fosfórico 37% e sem "primer"; G3: Adper Single Bond 2 (3M ESPE®), sem condicionamento ácido; G4: Adper Single Bond 2 (3M ESPE®), após condicionamento com ácido fosfórico 37%; G5: Adper Easy One (3M ESPE), sem condicionamento ácido e G6: Adper Easy One (3M ESPE®), após condicionamento com ácido fosfórico 37%. Os reparos foram confeccionados com o compósito Opallis (FGM®), cor A2. Após 24 horas os corpos de prova foram submetidos aos ensaios de cisalhamento (Instron - 0,5 mm/min). Os valores médios (MPa) após ANOVA2 e teste de Tukey e T de student (5%) foram: G1: 18,34 (6,73); G2: 16,49 (3,65); G3: 13,11 (3,64); G4: 19,86 (5,85); G5: 20,88 (4,82) e G6: 23,48 (4,36). O condicionamento com ácido fosfórico a 37% aumentou significativamente a resistência de união dos reparos confecciona¬dos com o sistema Adper Single Bond 2 (3M ESPE®) e não proporcionou aumento significativo na resistência de união dos reparos com os sistemas Adper Scotchbond Multi-Purpose (3M ESPE®) e Adper Easy One (3M ESPE®).

The aim of this study was to evaluate the effect of acid etching and type of adhesive on the bond strength of composite repairs treated with aluminum oxide. Sixty discs were fabricated with composite shade A2 (Filtek Z350 - 3M ESPE®), and aged for 6 months in water. After polishing, the surfaces were subjected to aluminum oxide treatment (45 pm) and divided into 6 groups with 10 specimens each: G1: Adper Sotchbond Multipurpose (ASM) (3M ESPE®) without etching and without primer, G2: Adper Sotchbond Multipurpose (ASM) (3M ESPE®) after etching with phosphoric acid 37% and without primer, G3: Adper Single Bond 2 (ASB) (3M ESPE®) without etching, G4: Adper Single Bond 2 (ASB) (3M ESPE®) after etching with phosphoric acid 37%, G5: Adper Easy One (AEO) (3M ESPE®) without etching, and G6: Adper Easy One (AEO) (3M ESPE®) after etching with phosphoric acid 37%. Repairs were made with the composite Opallis (FGM®), shade A2. After 24 hours the specimens were submitted to shear tests (Instron - 0.5 mm/min). Mean values (MPa) after ANOVA2, Tukey test and T stu¬dent (5%) were: G1: 18.34(6.73), G2: 16.49 (3.65), G3: 13.11 (3.64), G4: 19.86 (5.85), G5: 20.88 (4.82), and G6: 23.48 (4.36). The phosphoric acid at 37% significantly increased the bond strength of repair with the system ASB and did not increase the bond strength of repair with the systems ASM and AEO.

[Dental materials. A critical assessment from the viewpoint of alternative medicine]. / Zahnärztliche Materialien. Eine kritische Wertung aus komplementärmedizinischer Sicht.

Practical experience with unconventional treatments suggests that the paradigm used by conventional medical science to assess the impact of dental materials must be broadened. First, several diagnostic methods commonly employed to evaluate allergies and toxicological burdens are described and subjected to a critical analysis. These diagnostics include test methods used in the field of complementary medicine in addition to the traditional epicutaneous tests, the Lymphocyte Transformation Test and quantitative analysis of blood and urine. Finally, the fundamentals of toxicology in the low-dose range are discussed; in this context special attention is paid to possible factors enhancing the effect of various substance groups. The impact of dental materials is also viewed from the perspective of environmental toxicology. In addition, the authors discuss various paradigms for obtaining evidence of multifactorial causes and show why nonuniform results are obtained with dental materials. Reference is also made to new theories broadening our understanding of biological processes such as the Biphoton Theory, which has been the subject of increased discussion among quantum physicists in recent years. It becomes evident in this context that there are to date no evidence-based methods for demonstrating the absolute non-toxicity of dental materials. Finally, it is shown - on the basis of various reports provided by a practitioner of complementary medicine in private practice - that, in patients with chronic diseases, unconventional therapies integrating these insights may by the only effective therapeutic options to succeed.

The mechanism of gingiva metallic pigmentations formation.

The occurrence of blue-grey areas in the soft tissue represents one of the problems affecting patients whose teeth have been restored using metallic materials. It is generally accepted that it is caused by mechanical penetration of a metallic material into the soft tissue. Several facts indicate that this mechanism is not general. The aim of the study was to determine an alternative mechanism of the origin of pigmentations, based on the corrosion interaction of metallic materials used in prosthodontics with the oral environment. The study was comprised of an analysis of pigment particles, determination of exposure conditions of metallic materials in vivo and laboratory evaluation of corrosion properties of the studied materials. Particles containing silver, sulphur and/or selenium could be seen in ultra-thin sections in the lamina propria gingivae. Comparison of the corrosion laboratory results with the results of in vivo measurements indicated the intensification of corrosion under these conditions. Amalgams and silver-containing alloys used for teeth restorations may release silver under the conditions of the oral cavity. The formation of soluble silver compounds in the sulcular area or in a crevice between the crown and the cast post-and-core reconstruction facilitates their transport to the soft tissue and subsequent deposition.

Double-blind study on materials testing with applied kinesiology.

Applied Kinesiology (AK) is a scientifically unproven method used in complementary medicine to recognize the (in)tolerance of dental materials. Test-retest reliability of AK was examined. The working hypothesis was the assumption that the reliability of AK would not exceed random chance. Two dentists qualified in AK examined 112 volunteers to determine individual (in)tolerance toward two dental composite materials. After the first examination, 31 subjects were excluded from further testing. At the end of the open test phase, 34 of 81 participants had been classified as "tolerant", and seven as "intolerant" to both materials. The remaining 40 individuals showed a combination of either tolerant (to material I)/intolerant (to material II), or the reverse (n = 20 each). Retrieval rate was tested under blind conditions. In 14 cases, the results of the open and blinded tests matched, whereas in 26 cases they did not (95% confidence interval, 21%-52%; p = 0.98). This outcome confirmed our working hypothesis.

Recommendations for determining biocompatibility and safety for the clinical use of metals in dentistry.

Determining the safety of dental materials through laboratory and animal testing before widespread use of such products in humans is critical to the continued use of many materials in dentistry. The patient and the dentist have the right to expect that a manufacturer has adequately evaluated a product for safety as well as effectiveness for its intended use before making the product commercially available. Although the use of dental amalgam and casting alloys is widespread, there is insufficient documented evidence to recommend discontinuing the use of either dental amalgam or base metal casting alloys. Unless it can be shown that a patient is hypersensitive to the metal and that the hypersensitivity is indeed a causative factor in a systemic disease, replacement of existing restorations is not recommended. Nevertheless, there are specific areas of future research including actions a dentist should implement. The dentist should document cases of sensitivity to metals and become familiar with the symptoms arising from metal exposure. In screening new products for use in dentistry the FDI Technical Report No. 9, Recommended Standard Practices for Biological Evaluation of Dental Materials is relevant. The series of recommended tests for metals to be used in dentistry include initial tests to determine acute toxicity, secondary tests such as those to evaluate irritation to the tissues in contact with the metal and usage tests, i.e. tests in animals simulating intended clinical use in humans.

Turpentine-induced hypersensitivity to peppermint oil.

After a dental operation a former laboratory technician was referred to our clinic because of swelling of his tongue, lips, and gingival mucosa. Patch testing with the ICDRG standard test battery gave positive reactions to colophony, balsam of Peru, and turpentine peroxides. Further patch testing revealed hypersensitivity to peppermint oil (an ingredient of several dental preparations) due to the sensitizing properties of three ingredients: alpha-pinene, limonene, and phellandrene. These compounds also occur in turpentine oil, a substance used in the patient's laboratory.