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A new type of material consisting of a ceramic substructure infiltrated with a composite material--referred to as a hybrid ceramic--is currently being introduced for dental CAD/CAM use. The characteristic brittleness of ceramic is thus replaced by an elasticity resembling that of natural human dentin. The material features a high fracture load value of 2980 N, and is straightforward to process in CAD/CAM milling machines. This article presents a case example describing the manufacture of a veneer restoration.

The clinical observation describes the case of a 20-year-old woman who has consulted for aesthetic and functional reasons. She presents a skeletal class III normodivergent, an occlusal class III with a lower proalveoli quite marked. In addition, a lingual dysfunction which manifests itself by important anterior diastema and dento-dental disharmony at the upper jaw complicates the case. The undertaken therapeutic project starts with a first step of a lingual praxis rehabilitation, followed by an orthodontic step and upper lateral incisors-plasty. The purpose of those results is the evaluation of the stability two years later, which was reported positive.

The success of all-ceramic crowns and increased patient demand for metal-free, tooth-colored restorations has led to the development of many different restorative systems for all-ceramic fixed dental prostheses (FDPs). The most recent core materials for all-ceramic FDPs are the yttrium-tetragonal zirconia polycrystal (Y-TZP)-based materials. Yttrium oxide is a stabilizing oxide added to pure zirconia to stabilize it at room temperature and to generate a multiphase material known as partially stabilized zirconia. This exhibits very high flexural strength and fracture toughness along with good biocompatibility and excellent esthetics. This clinical report describes the use of the Lava All-ceramic system, based on Y-TZP, for the fabrication of two fixed dental prostheses (FDPs) in the maxillary anterior region of the patient, restoring both esthetics and function.

The aim of this study was to examine to what extent excess space must be taken into consideration as an etiological factor in upper canine impaction with special attention paid to the role of the adjacent laterals. To clarify this question the pre- and post-treatment models of 63 patients with a total of 84 impacted cuspids were measured and the cephalograms of 116 patients having 144 impacted cuspids were analyzed. The results of this study revealed: 84.5% of the cuspids were palatally impacted while 15.5% were labially impacted. An arch deficiency was found in only 18% of the palatally impacted cuspids, whereas there was an arch-length deficiency in 46% of the buccally impacted. In 35% of the cases there was a correlation between peg shaped laterals and palatal impaction, however, such was not present in the patients with vestibular retention. Finally the cephalometric data revealed horizontal growth characteristics in 80% of the palatally impacted canines as opposed to 23% in those labially impacted.

Account has to be taken of the increased aesthetic awareness of the adult patient by all sub-specialties of dentistry. Here, orthodontics often plays the role of a central link between periodontics and prosthetics. Taking pathological migration of the incisors as an example, the pathogenesis, therapeutic procedures and orthodontic possibilities for the restoration of normal dentofacial aesthetics are demonstrated and discussed.

In three adult patients with Class II division 2 malocclusions the upper lateral incisors were extracted either because of their deformity or nonvitality. Orthodontic space-closure was performed in all three cases to prevent any prosthetic procedure. The sequence of therapeutic steps and difficulties during treatment are discussed.

The biomechanics of space closure in adult patients with loss of periodontal attachment is described. In order to achieve an even force distribution in the periodontium, force was reduced and the moment to force relationship was increased. beta-TMA-T Loops of 0.016 inch x 0.022 inch and 0.017 inch x 0.025 inch cross sections were investigated. With an automatic testing device force and moment values were determined.

After periodontal therapy 12 patients with advanced alveolar bone loss were orthodontically treated and recalled for approximately 51.1 months. Orthodontic tooth movement resulted in a mean overjet reduction of 1.7 mm, a mean overbite reduction of 1.3 mm and closure of the anterior spaces. No significant differences were observed in the probing depths and attachment levels between the test and control teeth. 31% of the treated teeth showed signs of root resorption. The results indicate that orthodontic therapy in patients with successfully treated advanced periodontal disease does not lead to further attachment loss if the patients are periodontally well maintained.

In so-called late cases, the correction of a diastema will frequently be achieved only by prosthetic measures, co-operation with an orthodontist being recommendable. The various possibilities of treatment are represented by case reports.

After a summary of the theoretic basis for the indication of an operative reduction of the tongue by the therapy of malocclusion, the results of the tests were individually analysed. A sure influence of the reduction of the tongue can only be proved for the averting of a threatening relapse after an operation of progenia. The ability of speech stayed without any influence in 12 cases and in 3 cases it got better or worse. The numerous late sequels in form and function of the tongue make it necessary to be carefully in indication of the reduction of the tongue by the therapy of malocclusion.

The present paper deals with first personal experience. The indications concern orthodontic space elimination and movement of single teeth in the anterior region. This method is a true rationalization in orthodontic practice.

Familial occurrence of diastemas in the pericanine region of the maxilla and mandible was described which differs from known localizations. Postcanine occurrence was found in the maxilla; precanine occurrence, in the mandible. This therefore differs from phylogenic diastemas, such as the diastemas in the deciduous dentation of monkeys and primates. Reasons for the influence of local disturbances (e.g., aplasia, dystopia, persistence of embryofetal frenula) could not be determined; ritual (traumatic) mutilation could also be excluded.

The behaviour of interdental gaps is checked during the milk teeth period on denture models of 33 regular gap milk dentures and 49 milk dentures with protrusion of the upper incisivi. A "physiological gap" could be found in only 2.3% of cases.

1,030 sets of teeth classified by Eichner as type A (single gap between the teeth) were examined in view to tooth shifting, tipping and periodontal condition on the gap's antagonists and the gap's neighbours. If it is necessary to close the gap with prosthetic means is dependent on the mode of individual reaction which is estimated on a long-term-observation of gap areal (clinical and radiographic). The stability of position of gap antagonist or gap neighbour point to a positive bone factor (by Glickman). Only those cases ought not to treat.

In this study praevalence and stage of some selected symptoms within the orofacial complex were investigated in 600 normal children living in Jena (300 boys and 300 girls). The first problem of this study consisted in registering the biological variability of 6 symptoms (bit abnormality, protrusion of the lower lip, diastema, palatal height, size of the tongue, fissured tongue) in a normal group, and secondly to find correlations between these symptoms. The results are listed for the age groups according to sex. The supposed causes that may lead to the development of these symptoms are discussed. Our results were compared with those of the literature. Difficulties and incompletion are involved in recording of the mentioned symptoms and their value of diagnosis.