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This paper provides a brief review of the history and development of mini screws and presents its structural features, with particular reference to the screw sizes relevant to clinical orthodontics, site selection and the different placement techniques. It covers the clinical applications of miniscrews, incorporating the principle of direct and indirect anchorage as well as the use of intraoral auxiliaries for distal movement of molars. The role of palatal miniscrews for retraction of anterior teeth, and when used in combination with buccal miniscrews for intrusion of buccal teeth is also covered along with the possible causes of miniscrew failure. Finally, a conclusion is put forward that the use of miniscrews in orthodontics has a valid clinical basis and will enhance the scope of orthodontic practice.

Patients are frequently being asked to wear orthodontic retainers for as long as they want their teeth to remain in the post-treatment position. Fixed retainers, which are placed on the lingual surface of anterior teeth only, have the advantage of minimal compliance issues but are not without their problems related to wire fracture, adhesive failure and potential gingival or periodontal disease. Plastic retainers, although associated with relatively good aesthetics and compliance, have limitations related to their physical and mechanical properties. This paper describes a chrome cobalt metal retainer that could be used as a long-term retainer with few drawbacks. The properties of chrome cobalt are described and the clinical procedure is outlined.

Lower labial segment irregularity is a feature that is presenting more frequently as greater emphasis is placed on aesthetics than ever before. The authors report on a removable appliance that is easy to construct and use and is designed to deal with mild labial tooth irregularity. In cases of crowding the aligner can be used in conjunction with inter-proximal stripping. The device incorporates a removable labial bow attached bilaterally to a sliding lock. This lock permits the addition of sectional archwires to the labial part of the appliance. The versatility of the aligner allows round and rectangular wires of different materials and dimensions to be placed with or without bends.

Mini-screw implants, often referred to as temporary anchorage devices (TADs), have become an accepted component of orthodontic treatment. The comparatively simple technique for the placement of these mini-screws is described with emphasis on the importance of correct site selection as well as an understanding of the possible complications that may arise. The application and description of appliances incorporating mini-screws are described with the aid of typodont models and clinical examples. While the technique is of primary relevance to orthodontists, the use of mini-screws as an aid for pre-prosthodontic tooth movement is also of relevance to prosthodontists. From the examples described in this paper, extrapolations can be made by individual clinicians to situations relevant to their particular treatment plans. Examples of appliances used in conjunction with mini-screws are described; however, depending on the requirements of individual malocclusions, these designs may be modified.