Article
Occlusal Splints for Bruxing and TMD – A Balanced Approach?
(Dent Update2018; 45: 912−918)
I would like to respond to an article published in the November issue of Dental Update. There are a number of issues with the article in which the authors, Jagger and King, make some comments without adequate references.
The authors report that evidence on splints and efficacy is limited and most articles are opinion based. On this I agree: there are limited clinical studies for occlusal splints.
The authors mention in the section on ‘Anterior bite planes’ that ‘the splint must contact the opposing 4 incisors to prevent overloading teeth’. There is no scientific reference to suggest that the teeth would be overloaded. On the contrary, EMG studies have been shown to reduce forces when posterior contacts are removed.1, 2
The authors suggest that anterior bite planes cause teeth to supra-erupt. This is a common myth that sadly causes much debate and confusion in dentistry. The Dahl appliance is often referenced with regard to supra-eruption, however, this can also be misleading. Bereznicki et al refer to a review of the Dahl concept by Poyser et al ‘the time to achieve intrusion/extrusion of teeth to a new, desired vertical dimension is considered to range from one to 24 months, with continuous 24 hour a day wear of an appropriate, suitably designed appliance. The Dahl appliance is designed to be bonded in the patient's mouth and worn 24/7 with all teeth except those in contact to never be in any function. The idea is to supra-erupt the posterior teeth during a restorative phase of treatment. This is not the same as a patient using a night time splint for a few hours’.3, 4 The research by Kinoshita et al would also suggest that teeth are unlikely to supra-erupt.5
The authors have a section on SCiTM. It may have been prudent for the authors to speak to us at S4S about this, considering our involvement as distributors of the mass produced splint and manufacturers of the custom-made SCiTM. The SCiTM is still called NTI-tss in all countries outside of the UK. The SCiTM (Trademarked in UK) is available as a ‘chairside or surgery fitted’ device. This is a mass produced splint that generally covers the anterior teeth. The SCiTM can cover full arches and both arches, if required.
Furthermore, with regard to the SCiTM section, the authors suggest that the device works by stimulating the periodontal ligaments, assuming proprioception. On the contrary, the SCiTM devices are still effective during sleep when there is no proprioceptive feedback during certain phases of sleep.6
The authors go on to suggest that the SCiTM device is normally used on the maxillary teeth. In fact, the manufacturer and inventor, J Boyd and others, who teach the fitting of these appliances, suggest that the default is to fit the device on the lower arch. There are reasons why this is suggested and, of course, there are exceptions.
The authors mention occlusal changes in regard to the SCiTM and reference the Stapelmann and Türp literature review as if to suggest to the reader that the research proves the appliance causes occlusal changes, when in fact the review suggests that ‘such devices’ may be successfully used for the management of bruxism and TMDs.7 However, to avoid potential unwanted effects, it should be chosen only if a patient is sure to be compliant with follow-up appointments. There are many references to occlusal changes with other full arch occlusal splint use.3, 8, 9
The authors say ‘Due to its size it is susceptible to being swallowed or inhaled’. This is a dangerous statement. The device, which is CE marked and FDA approved, has regulations and rules to follow. If there are any adverse events they must be reported via MAUDE, the agency that investigates medical devices and drugs that have side-effects. (https://www.accessdata.fda.gov/). A search of MAUDE reveals that there have only ever been four adverse events reported. None of the events relates to inhalation or swallowing. Considering that there have been perhaps more than 10 million NTI-tss/SCi devices fitted since the 1990s, it is not correct to say that they are ‘susceptible to being swallowed or inhaled’.
The authors may not be aware of the research by Blumenfeld et al.10 Results from 512 dentists, reporting on 78,111 NTIs fitted, showed 98.1% patients wore the device with no problems, 1.6% had bite changes and 0.3% claimed aspiration. There were no reported cases of aspiration verified by radiographs. The figure of 0.3%, even if they were confirmed reports, does not suggest that they are ‘susceptible to being swallowed or inhaled’.
In summary, the article makes assumptions based on the authors' own opinions. This can lead the reader to believe that myths exist on the subject of occlusal splint therapy, leading to increased confusion and frustration.