The mammalian tongue plays a fundamental role in various physiological and behavioral activities. Significant morphological variations have been recorded in the tongue of several species. This study aims to obtain detailed histological and morphometric information about the filiform papillae on the surface of rat tongue. The tongues of five 10-month-old Wistar rats were utilized, which were later examined with a stereo-microscope. Fragments from the three regions of the tongue were collected for histological investigations. The tongue of the Wistar rat has an intensely keratinized stratified squamous epithelium, with the highest degree of keratinized epithelium covering the filiform papillae. The filiform papillae differ in density, with the highest density recorded on the posterior part of the lingual body and the lowest density on the protuberance. The shortest filiform papillae were observed on the apex of the tongue and the tallest on the anterior part of the lingual body. Interestingly, the orientation of the filiform papillae on the lingual protuberance was inclined posteroanteriorly, in the opposite way as compared to the papillae from all the other regions of the tongue. Histologically, a difference was recorded in the structure of the covering epithelium of the anterior vs. the posterior face of the filiform papillae.

Background and Objectives: Implant osseointegration has been widely studied over the past few decades, particularly focusing on surface modifications that aim to improve integration. However, the literature includes few studies regarding the role of the endosteum in early osteointegration. Therefore, the aim of the present work is to approach the technique of implant insertion into bones with marrow, with an emphasis on the use of implants that are long enough to achieve marrow penetration. Materials and Methods: Titanium implants were inserted into the femurs of eight eleven-month-old rabbits. Fourteen days later, the animals were euthanized in accordance with the current legal and ethical guidelines. The histological processes that occur at the bone–implant interface were investigated. Histological sections of the bone–implant interface were colored using the Trichrome’s Goldner method, and were further analyzed and photographed using an Olympus microscope. Results: The histological analysis showed that during the initial osteointegration phases, the newly formed bone originated from the endosteal–medular zone. Periostal proliferation was observed only during the early stages. The bone that proliferated on the implant’s endosteal/medullary interface exhibited a surface area approximately 6 times larger than that of the bone formed on the osteal surface. Also, its length was approximately 25% longer. Conclusions: The bone tissue that proliferates on the endosteal and marrow surface of the implant increases significantly the bone–implant interface, and creates the setting for a good secondary stability. The findings suggest several clinical implications, as follows: penetrating the bone marrow during the insertion of short implants allows for increasing the bone–implant interface; the flap should be carefully managed; the integrity of the periosteum must be kept, as this is a key anatomical structure in cases of deficient bone marrow (i.e., severe mandible atrophy or vertical ridge augmentations).

Background and Objectives: The insertion of endosseous implants requires the alveolar bone to be drilled, which produces alterations of the osseous neoalveolus approximately 1 mm deep, an area that will later be subjected to osseous renewal. The healing of the bone around the inserted implant is complex and depends on numerous factors, amongst which the size of the insertion orifice relative to the diameter of the implant, the design, and the pace and depth of the threads play an essential part. Therefore, the aim of this paper is to investigate from a histologic point of view the osseointegration of the implants inserted in a rabbit cortical bone by creating a 150 µm high healing chamber. Materials and Methods: 5 mm-long and 2 mm-wide titan implants were inserted into the femur of 15 12-month-old rabbits by using a drill with a 1.8 mm diameter, obtaining a spiralled healing chamber 150 µm high. The animals were euthanized after 7, 14, and 28 days according to effective legal and ethical protocols. The bone around the implants was severed 5 µm thick. After coloring with the Tricrom Goldner method, the sections that intercepted most centrally the intervention area were examined and photographed with an Olympus microscope. Results: The histologic result showed osseous healing within the healing chamber in the third to the endosteum of the implant after 7 days from the insertion. After 14 days, the osseous healing spread to 2/3 of the healing chamber. After 28 days, the whole healing chamber was occupied by bone. Conclusions: The healing chamber favored proper conditions for osseous healing, which began at the level of the endosteum. This statement is based on the histologic findings of bone formation after 7 days only in the third of the endosteum of the healing chamber. A 150 µm height of the healing chamber obtained in the rabbit cortical bone does not pose a risk of connective tissue proliferation.

Oxidative Stress Evaluation in Rats Anesthetized with Isoflurane or Sevoflurane