Irina Maftei, Iulia Cătălina Săveanu, Oana Dragoș, Carina Balcoș, Ioan Dănilă
The purpose of this study was the OM = optical microscopy analysis of the dentinal HL=hybrid layer of two materials with metal alloy particles used in minimally invasive cavity preparations. The study included 10 human premolars and molars, extracted for orthodontic or periodontal reasons. The extracted teeth were used in the study after obtaining a informed consent from the patients, in compliance with the protocol approved by the ethics committee of UMF Gr.T.Popa Iasi. Samples were divided randomly into two equal groups (N = 5): GR.1 (N = 5), GR2 (N = 5). Minimally invasive occlusal cavities were made using a mechanical preparation. We used cylindrical diamond burrs and carbide globular no. 1 burrs. The restorative materials used were: PAA=PolyAcrylic Acid, SE = 3M ™ Scotchbond Etch ™, dental adhesive ASBP = Adper Single Bond Plus (3M ESPE), glass-ionomer with metal alloy particles MM = MIRACLE MIX (3M ESPE) and non gamma 2 amalgam A=ANA2000. The analyzed groups were: GR.1:(5)PAA;MM and GR.2:(5)SE™;ASBP;A. Materials were used according to the manufacturer’s instructions, the resulting samples were thermo cycled 500 cycles (5 0 -55 0), sectioned, viewed by OM=ZEISS–AXIO-CAM-MRC5 and statistically analysed (ANOVA, p ≤ 0.05). Statistical data processing was performed with Microsoft Excel and SPSS 14.0, p ≤ 0, 05. The results obtained by quantitative analysis of the HL indicate that there are differences (p ≤ 0.05) between groups in favour of the samples filled with amalgam 10.37 (± 2.62). Conclusions: The restoration material and the use of a dentinal adhesive dimensionally influence the HL size.