There are many techniques and materials to fill the root canal system. In this paper a number of the most popular techniques and materials is discussed mainly with the purpose to give an overview, and to understand the advantages and disadvantages of the various types of root fillings. Discussed are sealers based on zinc oxide-eugenol, synthetics and those that adhere to dentine or to which medicaments have been added. Of the various filling techniques the cone cementation techniques like single cone and lateral compaction are discussed, while of the warm techniques the lateral, vertical, and thermomechanical compaction as well as injection and core carrier techniques are described.

There are a lot of studies discussing success rates of root canal treatment. They show a big variety in their outcomes. Success rates are reported between 54 and 96 percent with a majority reporting a figure towards the higher end of the range. Despite high success rates reported, there are still cases showing no healing after an evaluation period. At that point the dentist has to make a decision: retreatment or surgical endodontics. To make this decision various factors influencing the outcome should be considered carefully. The overall conclusion is that when failure occurs, endodontic retreatment is the first treatment of choice. Periapical surgery is a treatment option wich should carefully be considered in specific circumstances.

Endodontically treated teeth can be restored in several ways. The prognosis of these teeth does not only depend on an adequate endodontic treatment, but also on a solid restoration that protects the weakened tooth against fracture. Adhesive core build-up procedures, possibly with the application of new generation glass fibre posts, become more and more in favour. This article is dealing with the considerations that should be made when adhesive core build-up procedures are used and more specific with core build-up procedures for endodontically treated premolars.

Bone is continuously remodelled to maintain its strength and structural integrity. Remodelling is the result of an equilibrium between bone formation performed by osteoblasts and bone resorption performed by osteoclasts. In osteopetrosis this equilibrium is disturbed by a defect in the osteoclastogenesis or by disfunction of osteoclasts. Osteopetrosis is divided into four types: malignant infantile osteopetrosis, intermediate osteopetrosis, and two types of autosomal osteopetrosis. Malignant infantile osteopetrosis is usually diagnosed within the first year of birth by bone sclerosis and bone marrow obliteration. This type is very severe and usually results in death within a few years. The intermediate type usually appears before the age of ten and leads to recurrent pathologic fractures and cranial nerve compression. Autosomal dominant osteopetrosis is usually mild and consists of two sybtypes. Type I involves marked thickening of the cranial vault. Type II patients have predominantly sclerosis of the pelvis, the vertebrae and the base of the skull. Type I and II patients may often be long-lasting asymptomatic, but will eventually present with pathologic fractures, bone pain, and the effects of cranial nerve compression. Oral problems of osteopetrosis are delayed tooth eruption, absence of some teeth, malformed teeth, enamel hypoplasia, disturbed dentinogenesis, hypomineralisation of enamel and dentin, propensity for tooth decay, defects of the periodontal membrane, thickened lamina dura, mandibular protrusion, and the presence of odontomas. Tooth removal should be limited as it may induce bone fractures and osteomyelitis.