Journal of Orthodontics

Lingual orthodontic appliances have experienced a renaissance in the UK over the past 5 years, becoming more widely accepted as a suitable alternative to conventional labial appliances when treating most malocclusions. Clinically improved laboratory techniques have overcome many of the difficulties that a previous generation of orthodontists encountered when first trying to embrace this innovative technique to correct malocclusions. This article provides a brief history of lingual orthodontics. It will discuss the development of the technique, the reasons for its initial rise and fall in popularity, and more recent developments that have re-established its popularity among orthodontists in the UK.

Despite being available for over 30 years, it is perhaps only over the past decade or so that lingual therapy has entered into the mainstream and become a viable treatment option. This paper outlines the problems encountered with traditional lingual techniques and describes how fully-customized lingual appliances have been designed to overcome many of the issues that had risked confining lingual orthodontics to the margins of clinical practice.

Lingual orthodontics is increasing in popularity, with more adults receiving orthodontic treatment and opting for truly invisible appliances that do not have any limitations on the type of tooth movement they can achieve. In addition, there are a growing number of children receiving lingual appliances as they have been shown to significantly reduce the incidence of decalcification. Combining this growth in popularity with advances in computer technology, it is possible to treatment plan, design the appliance and have it custom made all with the click of a button. This article highlights the different methods that have been utilized in the fabrication of lingual appliances.

Bonding techniques in lingual orthodontics differ slightly from their counterparts in labial treatment, although there are many shared features. If protocols are followed correctly, bonding outcomes are very predictable and lingual bracket bonding can be integrated into a mixed orthodontic practice with the minimum of disruption. Here, we highlight the fundamentals of both chemical and light/dual cure bonding procedures using lingual appliances, and discuss special bonding circumstances. Although not exhaustive, this article will provide essential information for those operators embarking on the bonding of lingual appliances.

As the number of adults that seek orthodontic treatment continues to grow, so too is the popularity of lingual fixed appliances. Although the aesthetic advantages associated with these systems are obvious, for some orthodontists, there has been a reluctance to offer lingual-based treatment to their patients. This is often based upon the perceived problems associated with lingual braces, relating to discomfort and difficulties with speech for the patient, and problems in using these appliances for the orthodontist. Although some of these factors have been investigated, the current evidence base is weak, possibly due to the fact that these are evolving appliance systems. Among the studies that have been carried out to date, pain and discomfort for the patient appears to be similar following the placement of labial or lingual appliances, although the onset can be earlier with lingual brackets and the location different, with the tongue more frequently being involved. Customized lingual brackets may be associated with less pain than pre-fabricated. In addition, patients do seem to be more likely to experience difficulties with speech and mastication when fitted with a lingual appliance. However, there is some evidence that the lingual surfaces of the teeth are more resistant to early demineralization and caries. Little data exist regarding treatment outcome and ease of use for the orthodontist, either between lingual or labial appliances or between different lingual systems. Further research is required to investigate the efficiency of lingual appliance systems, both for the patient and orthodontist.

The increased use of lingual appliances has meant a continued evolution in the design of lingual brackets. These changes in appliance and bracket design have tended to focus on reducing bracket thickness, with the aim of making appliances more comfortable. A thinner bracket design appears to have had some positive effects on the quality of speech, as well as comfort whilst appliances are in place. However, despite these improvements, some patients do struggle with their speech during treatment, far more than others. It is important therefore, when consenting patients for lingual orthodontic treatment, to ensure that they are made aware of the potential for speech to be disturbed, particularly in the early stages of treatment. The purpose of this article is to outline some of the issues associated with speech problems and discomfort during lingual appliance treatment, so that practitioners are able to advise patients who may be considering this kind of treatment. Advice given during the consent process, including appliance selection, procedures for maintaining oral comfort and management of individual speech issues, will all help lingual patients cope with any speech problems they may experience during their treatment.

Contemporary lingual orthodontic appliances offer an aesthetic and accurate means of treating malocclusion. Managing extraction-based treatments with lingual appliances presents a number of challenges. This article discusses the specific biomechanical considerations associated with extraction treatment and outlines clinical techniques that can optimize treatment outcome in these cases.

The Incognito fully customized lingual appliance provides excellent torque control. This offers the potential for class II correction using inter-maxillary traction without the usual iatrogenic effects associated with their use. A case is presented showing the potential of these appliances in controlling torque and achieving full class II correction on a non-extraction basis.

Incognito is a fully customized lingual fixed appliance system of high precision and limited adjustability. It is therefore important to incorporate as much detail as possible into the planning and communication of the appliance prescription. A systematic approach to this is suggested, breaking it down into torque, tip, tooth width and morphology, vertical tooth positioning, arch width and arch form. The clinician relies upon the laboratory technician to interpret correctly this guidance in the preparation of the set-up. Verification of the set-up by the clinician before appliance manufacture is not compulsory. The potential risks of not verifying the set-up are discussed.

The two-dimensional (2D) lingual bracket system represents a valuable treatment option for adult patients seeking a completely invisible orthodontic appliance. The ease of direct or simplified indirect bonding of 2D lingual brackets in combination with low friction mechanics makes it possible to achieve a good functional and aesthetic occlusion, even in the presence of a severe malocclusion. The use of a self-ligating bracket significantly reduces chair-side time for the orthodontist, and the low-profile bracket design greatly improves patient comfort.