New zirconia compositions with optimized esthetic properties have emerged due to the fast-growing technology in zirconia manufacturing. However, the large variety of commercial products and synthesis routes, make impossible to include all of them under the general term of “monolithic zirconia ceramics”. Ultra- or high translucent monolithic formulations contain 3–8 mol% yttria, which results in materials with completely different structure, optical and mechanical properties. The purpose of this study was to provide an update to the current knowledge concerning monolithic zirconia and to review factors related to strength and aging resistance. Factors such as composition, coloring procedures, sintering method and temperature, may affect both strength and aging resistance to a more or less extend. A significant reduction of mechanical properties has been correlated to high translucent zirconia formualtions while regarding aging resistance, the findings are contradictory, necessitating more and thorough investigation. Despite the obvious advantages of contemporary monolithic zirconia ceramics, further scientific evidence is required that will eventually lead to the appropriate laboratory and clinical guidelines for their use. Until then, a safe suggestion should be to utilize high-strength partially-stabilized zirconia for posterior or long span restorations and fully-stabilized ultra-translucent zirconia for anterior single crowns and short span fixed partial dentures.

INTRODUCTION: Following tooth extraction various alterations in the aesthetic zone of the oral cavity can be expected. These are alveolar bone loss as well as structural and compositional changes of the covering soft tissues. Thus, the clinician is confronted with a challenging situation regarding the decision-making process required to provide an optimal treatment solution. PURPOSE: To highlight the importance of preserving the alveolar ridge in the aesthetic zone as well as presenting the methods that exist to achieve it. METHOD: A review of the literature of the last five years was performed, with keywords such as: alveolar soft tissue volume; assessment method; esthetic dentistry; extraction socket; wound healing. RESULTS: The criteria that affect the maintenance of the alveolar ridge, are the time of placement of the implant, the quality of the bone in the extraction socket and the amount of bone remaining in it. The clinician should also have a picture of the quality of the soft tissues that surround the bone socket. CONCLUSIONS: It is very important to realize that the clinical decision-making process for alveolar ridge preservation in the esthetic zone starts before tooth extraction. The placement of a dental implant in the aesthetic zone can be performed after 2 months if the soft tissues remain Intact. In all other cases where implant placement is not possible, alveolar ridge preservation procedures should be considered.

INTRODUCTION: The technique of Οsseodensification has recently appeared in clinical practice by Salah Huwais for the placement of dental implants. This technique relies on the use of special burs (Versah), which in contrast to the conventional drilling techniques these burs do not excavate bone. PURPOSE: To highlight the importance of Οsseodensification in clinical practice. METHOD: A literature review for the last five years was performed, with keywords such as: Implant stability, osseodensification, osteotomy. RESULTS: During osteotomy, unlike conventional implant drills, the bone is advanced into the implant shaft instead of being removed. Versah burs allow for more accurate osteotomy preparation and reduce any potential drilling vibrations. With these special burs we have the ability to push the bone towards the base of the implant lumen. Finally, a closed sinus lift can be achieved by lifting the sinus membrane up to 3 mm without the use of a foreign graft. CONCLUSIONS: Οsseodensification has helped the clinician to achieve the maximum possible primary stability during the placement of the implant. The fact is, however, that there is a lack of sufficient documentation. It is therefore necessary to carry out more clinical studies, so as to lead to safer conclusions about the long-term results of the above technique.

INTRODUCTION Reduced periodontal support is a challenge that clinicians often face during rehabilitation of compromised dentition. The close and intricate relationship between the periodontal tissues and the processes of tooth movement suggest that adjunct orthodontic therapy may play an important role in overcoming these problems. On the other hand, excessive movement of teeth beyond the anatomic boundaries of the alveolar process is commonly believed to contribute to further destruction of the periodontal tissues PURPOSE: To highlight the importance the periodontium health and root of the tooth during the orthodontic treatment METHOD: A literature review for the last five years was performed, with keywords such as: orthodontic appliances, healthy periodontium, recessions, systemic reviews. RESULTS: Root resorption can be observed during the orthodontic treatment which can follow up to tooth mobility as well as losing the tooth due to the treatment CONCLUSIONS: The correction of some orthodontic problems, such as excessively tipped molars, traumatic deep-bites and flared and spaced incisors, maybe particularly beneficial in periodontally compromised patients who are motivated to undergo treatment and demonstrate stable periodontal conditions. However, several factors may contribute to a harmful periodontal response including the use of heavy forces, inappropriate force systems and poor oral hygiene. Excessive and unrealistic tooth movements are also likely to result in reduced alveolar bone thickness, especially in patients with thin cortical plates. On the other hand, the response of the soft tissues is less predictable and likely to be influenced by multiple factors.

INTRODUCTION: Gingival recession, also known as receding gums, is the exposure in the roots of the teeth caused by a loss of gum tissue and/or retraction of the gingival margin from the crown of the teeth. The aetiology of the condition is multifactorial but is commonly associated with underlying alveolar morphology, tooth brushing, mechanical trauma and periodontal disease PURPOSE: To highlight the importance of covering gingival recessions and the presentation of various surgical techniques of covering receding gums METHOD: A review of the literature of the last five years was performed, with keywords such as: gingival recession, surgical flaps, root coverage techniques. RESULTS: Main reasons of covering gingival recessions are thermal hyperesthesia and esthetics of the oral cavity. The root coverage can be achieved by using free gingival graft tissue from the hard palate of the patient or biomaterials such as bovine and synthetic material. CONCLUSIONS: The choice of the right technique for covering the gum recession plays an important role in the treatment plan. However, the surgeon should be experienced and make all the proper treatment planning choices for the esthetic result