Additionally, access is easier for learn more the operator. The contralateral right side was used as the unligated control. All the animals were euthanised by cervical dislocation on day 11. Animals were assigned randomly to the following four groups (18 animals in each experimental group). Group 1: SO (sham-operated, submitted to the placement and immediate withdrawal of the nylon ligature around the cervix of second upper molars and treated with vehicle); Group 2: EP (experimental periodontitis treated with

vehicle); Group 3: SO + Vit E (sham-operated and treated with vitamin E); and Group 4: EP + Vit E (EP treated with vitamin E). After the treatment was finished, the experimental groups

were subdivided equally for alveolar bone resorption, histological, and biochemical (lipid peroxidation and SOD) analysis. The plus-maze test was performed according to Pellow et al.26 The plus-maze consisted of two open (48 cm × 48 cm × 12 cm) and two closed (48 cm × 48 cm × 12 cm) arms, which were connected by a central platform (5 cm × 5 cm) elevated 50 cm off of the floor. Rats were see more placed on the central platform facing a closed arm. During a 5-min period, the number of entries made into the open and closed arms, the time spent in each one and the percentage of time or to the number of entries in each arm was measured. The excised maxillae were fixed in 10% neutral formalin for 24 h. Both maxillary halves were then defleshed and stained with aqueous methylene blue (1%) to differentiate bone from teeth. Measurements of bone loss were made along the axis of each root surfaces of all molar teeth. Three recordings for the first (three roots) and two recordings for the second and third molar teeth (two roots each) were made. The total alveolar bone loss was obtained by taking the sum of the recordings from the buccal tooth surface and subtracting the values of the right maxilla (unligated control) NADPH-cytochrome-c2 reductase from the left

one, in millimetres.25 Morphometric analysis of the alveolar bone was performed with standardised digital photography (1.5×, SONY-DSC-H5, Japan), and the distance was measured with the Software Image J® Toll 1.37 (National Institutes of Health – NIH, USA). The alveolar bone was fixed in 10% neutral buffered formalin and demineralised in 5% nitric acid. Following this procedure, these specimens were then dehydrated, embedded in paraffin, and sectioned along the molars in a mesio-distal plane for haematoxylin–eosin. Sections of 6 μm in thickness, corresponding to the area between the first and second molars where a ligature had been placed, were evaluated by light microscopy (40×).