July 1, 2013
by Jeffory Wyscarver, RPSGT
The diagnosis and management of dental disease implies an effort by the practitioner and the dental team to identify and assess the problem as early as possible. This is consistent with the generally accepted principle that early treatment is likely the most conservative, least invasive, and most likely to achieve optimal results for the patient.
For example, it is unreasonable to manage dental cavities by waiting until the tooth decay is extensive. As with any disease or disorder, a reliable, predictable method that can detect the problem early creates the opportunity for prevention. Early diagnosis and interceptive treatment is considered the best approach in the management of TMD and bruxism and their associated general jaw pain; tooth facet wear and damaged teeth initiate intervention.1 The Bruxism/Sleep Monitor (Oral Science, Montreal, QC.) enables the clinician to detect parafunctional bruxism before symptoms occur. Moreover, the Monitor quantifies and reports the interactions between bruxism, snoring and sleep apnea, which often confound therapy. This data provides the dentist with invaluable information that focuses the practitioner to a more effective treatment decision.
Measuring the jaw muscle at night during sleep alone is well-established as a diagnostic technique. Unfortunately, due to the complexity of the airway and jaw muscle interactions, simply evaluating the masseter or temporalis muscle in isolation has a limited benefit. Measuring this muscle group while awake, as a conscious test, also has rather limited value, reducing the effectiveness and usefulness of daytime testing. These and other drawbacks have seriously limited the early detection and prevention of TMD and bruxism. Fortunately, new techniques and new technologies are facilitating this area of diagnostics and treatment for the dental profession.
The typical full Polysomnogram (PSG) measures a portion of the jaw muscle system but is not designed to assess for bruxism. The full PSG measures the activity of the sub-mentalis muscle for the purpose of establishing atonia, a hallmark feature of REM (rapid eye movement) sleep.2 There are two major concerns with the PSG with the respect to measuring the masseter and/or the temporalis muscle for TMD and bruxism. First, the location used to establish atonia does not adequately reflect abnormal muscle activity during sleep. Second, the “sleep community” does not identify or assess TMD and bruxism issues; it is generally their view. These are “dental” issues.3
Craniofacial Pain Centers and TMD Specialists often take surface electromyography (EMG) measurements while the patient is awake, sitting up in a dental chair. The surface EMG lead is attached to the masseter andor the temporalis, and the patient is asked to bite down hard to the point of slight discomfort. The strength of the bite force is measured and recorded. Subsequently, another measurement is taken with a therapeutic device placed between the teeth in the mouth. The therapeutic device prevents full occlusion, predictably resulting in a weaker EMG signal.4
Thus, the clinician may feel assured that the therapeutic device is effective. Does this, in fact, make sense? Does the device translate to effective treatment? It is important to note that the assessment has been accomplished while the patient is awake and sitting up in the chair! Moreover, does daytime testing measure the true condition of the patient? Do the disorders and damages typically occur during daytime?
Can a clinician rule out Obstructive Sleep Apnea (OSA) while the patient is awake? After all, OSA is a function of sleep. There are elements of bruxism that occur only while the patient sleeps. For example, the maximum bite force while awake on average is 80uV to 125uV.4 Measurement with the Bruxism Monitor during sleep often yields bite forces exceeding 300uV! Just as OSA is a function of sleep, it is safe to assume that the bite changes from time to time during sleep. Based on the collected data, the jaw positioning and bite forces change dramatically during sleep; a therapeutic device that is useful while awake may not function while the patient is asleep. In addition, there are a number of factors that are unique to sleep, such as Rhythmic Masticatory Muscle Activity (RMMA), that contribute to jaw EMG activity.5
The management sequence for the awake bruxism patient is commonplace. Typically, the patient complains of bruxism (or the oral indications of bruxism are observed by the dental team). The dentist asks the patient to close their teeth as firmly as possible, and to grind from side to side and front to back. If required, the bruxism inhibitor is prescribed, and subsequently inserted into the patient’s mouth. The dentist then asks the patient to perform same antero-posterior and lateral movements as before, with the expectation that these activities are now more comfortable, and less noisy, for the patient.
A similar scenario for the awake snoring patient makes far less sense. The clinician confirms the patient’s complaint of snoring, and then asks the patient to snore several times, loudly. This activity serves as confirmation that the patient snores and a therapeutic snore inhibitor is prescribed. Once the snoring inhibitor is inserted into the patient’s mouth, the dentist asks the patient to snore loudly with the expectation that the snoring is now quieter. This rather ridiculous approach to snoring therapy is mentioned to highlight why bruxism and snoring are not treated in the same fashion.
Snoring is a disorder that is unique to sleep. There are simple methods for determining snoring while the patient sleeps, including reports from the patient’s bed partner. The methods for assessing bruxism while the patient sleeps are anything but simple. This evaluation is routinely not performed. Previously, there have not been any simple bruxism assessment methods available for measuring tooth clenching, clenching frequency, bite forces, and possible contributing factors triggering masseter or temporalis muscle activity while the patient sleeps.
DDME Inc. has developed a patient and dentist-friendly test that readily evaluates the masseter and temporalis muscle activity utilizing the following parameters:
• Bite force in micro volts
• Frequency of tooth clenching
• Categorization of masseter events into Tonic, Phasic and Mixed types and indices
• Associated tooth sounds4
• Overall performance of the airway
• Masseter/temporalis muscle activity and its interaction with snoring and sleep apnea
All of the above data is plotted along a single time axis. Including the performance of the airway is critical as there seems to be a relationship between airway issues and some masseter and temporalis muscle activity.
This comprehensive analysis and strategically combined reporting of parameters provides the dentist with tools that can be implemented into every practice and used to diagnose patient problems related to snoring, sleep apnea and TMD issues, even before obvious symptoms appear.
The dentist can categorize all the patients in the practice under five headings:
• Normal: Patient has no evidence of bruxism, snoring or airway issues.
• Snoring Only: Patient does not demonstrate significant airway issues except for snoring. The dentist has evidence through the Bruxism Monitor that dental treatment is not “silencing” a patient who may be apneic.
• Airway Issues: Patient demonstrates high likelihood of disordered respiration. The dentist may wish to refer this patient to a sleep clinic or to have the patient diagnosed by a Board Certified Sleep Physician (a service provided by DDME).
• Bruxism Only: Patient demonstrates significant masseter and/or temporalis activity in the absence of sleep apnea or snoring.
• Complex, Sleep Apnea and Bruxism: Excessive masseter andor temporalis muscle activity in the presence of
sleep apnea: This is a complex patient whose disease(s) need to be managed in tandem, not in isolation. The bruxism and airway issues co-exist and affect each other. The dentist cannot make the assumption that the management of one issue will cause the other to improve. The dentist may wish to refer this patient to a sleep clinic or to have the patient diagnosed by a Board Certified Sleep Physician at DDME.
The advantage of using the above matrix is that it readily points to specific treatment paths that, using objective evidence, can be readily implemented, dramatically reducing therapy times while improving outcomes. (Note: in the context of this article, the term “objective evidence” describes the results of a measurement used to make a clinical decision independent of the patient report.) The data provided by the comprehensive measurements will often identify a clinical issue before symptoms appear. This early diagnosis facilitates “preventative” intervention, greatly decreasing the physical discomfort that can be suffered by patients until and after symptoms appear. As well, many conditions are more easily treatable when they are identified and addressed at the earliest stages.
The Bruxism/Sleep Monitor is a recording device that is simple to use for both the patient and the dentist. Typically, one hour of training performed via the internet and phone is all the preparation that is required to make a dental office fully functional with this technology.
The Bruxism/Sleep Monitor is accompanied by software which automatically generates a preliminary patient report and provides the data for the dentist to categorize the patient. The process of generating the report takes less than five minutes (Fig. 1).
BRUXISM/SLEEP MONITOR DATA COLLECTION
The patient is instructed on the use of the Bruxism Monitor by the dentist or a team member (Figs. 2A-D). The instructions are simple and straightforward, but should be accompanied with a pictorial instruction sheet to ensure appropriate home compliance. There are four simple steps for the patient:
Step 1. Clip the Bruxism Monitor to the shirt or pajamas. Snap on the effort belts (chest and abdomen belts determine the presence of Central Sleep Apnea).
Step 2. Place the masseter muscle lead on the cheek as shown. Optionally, another lead can be placed on the temporalis muscle.
Step 3. Place the cannulla in the nares as indicated.
Step 4. Place the wireless oximeter on the wrist and finger as per instructions.
The patient is instructed to use the equipment overnight at home, while sleeping in his or her own bed. The major advantages of this approach include ease-of-use, the familiar environment of the patient’s own bedroom, and the elimination of the stress of a medical clinic. In the morning, the patient disconnects the equipment, and brings it back to the dental practice.
BRUXISM/SLEEP MONITOR DATA ANALYSIS
The dental team downloads the Bruxism/Sleep Monitor data into the computer with a single keystroke. The Bruxism Overview report is automatically generated allowing the dentist to place the patient into one of five categories:
Normal: No action needed
Snoring Only: Treat for snoring.
Airway Issues: Have the patient diagnosed by a Board Certified Sleep Physician (at DDME) then treat according to physician guidelines.
Bruxism Only: Treat for bruxism.
Complex, Sleep Apnea and Bruxism: Have the patient diagnosed by a Board Certified Sleep Physician (at DDME) then treat according to physician guidelines.
The Bruxism Overview report guides the dentist to selecting those cases that can be treated directly by the dentist in the practice. For more complex cases, the dentist has a Certified Sleep Physician’s supervision in treatment. For the most complex cases, as categorized by the Bruxism/Sleep Monitor, the dentist is given a medical recommendation to refer to a specialist.
BRUXISM/SLEEP MONITOR PATIENT REPORT
Case Review 1
Complex, significant sleep apnea with and Apnea Hypopnea Index (AHI) greater than 5 and a bruxism burst index greater than 4/hr (Fig. 3).
The data presented by the analysis of the Bruxism/Snoring Monitor data indicate that this patient exhibits nocturnal bruxism, and should be treated for sleep apnea with a relatively rigid appliance of robust architecture. Once the airway has been managed, a follow up measurement is recommended to determine whether the bruxism still persists at an abnormal level.
Case Review 2
Normal Study, no significant apnea was observed with an AHI of 1.6 and the bruxism burst index of 2.4/hr. (Fig. 4).
The data presented by the analysis of the Bruxism/Snoring Monitor data indicate that this patient exhibits normal biological levels. If the patient’s complaint includes excessive daytime sleepiness, a referral to a sleep specialist in indicated as the cause of the sleepiness has not been identified.
Peer reviewed methodology is used to differentiate the detectors for bruxism and airway related events.6,7 This allows the dental practitioner to confidently assess the patient’s status with respect to bruxism and disordered respiration, and to determine which cases are likely to have positive outcomes through dentally oriented treatment, and which require more specialized care.
The Bruxism Monitor permits a general practice dentist or specialist to take a quick, inexpensive, and non-invasive at-home measurement of bruxism/snoring problems once the patient exhibits symptoms or offers complaints. In fact, routine assessment of asymptomatic patients may diagnose problems before they are evident. The Bruxism Monitor is able to assess patients for snoring, apnea and bruxism, helping the dental practitioner to avoid some of the risks associated with improper diagnosis:
• Placement of an anterior splint for bruxism in a patient with apnea that increases the risk of pushing the tongue back in the airway.8
• Placement of a snore guard in a patient with sleep apnea that silences the disorder and delays treatment for apnea.9
• Treating central sleep apnea with a sleep appliance. OH
Mr. Wyscarver became a registered sleep technologist in 1992 and running large multi-site sleep centers as a skilled sleep clinician the technical expert. In 1998 Mr. Wyscarver took a position at CareFusion as a clinical specialist. During his tenure Mr. Wyscarver was promoted to Senior Marketing Manager for Sleep Diagnostics and Therapy. Currently his is the president at DDME Online. (DDMEOnline.com).
Oral Health welcomes this original article.
1. Bruxism: A Literature Review. Shilpa Shetty, Varun Pitti, C. L. Satish Babu, G. P. Surendra Kumar, and B. C. Deepthi; J Indian Prosthodont Soc. 2010 September; 10(3): 141–148. Published online 2011 January 22. doi: 10.1007/s13191-011-0041-5.
2. Unraveling the Mechanisms of REM Sleep Atonia. A Response to Kubin LK, Berger AJ, Funk GD, Soja P, and Chase MH. Critical Topics Forum. Sleep 2008; 31:1473-91
3. Mayo Clinic: http://www.mayoclinic.com/health/bruxism/DS00337. “Bruxism may be mild and may not even require treatment. However, it can be frequent and severe enough to lead to jaw disorders, headaches, damaged teeth and other problems. Because you may have sleep bruxism and be unaware of it until complications develop, it’s important to know the signs and symptoms of bruxism and to seek regular dental care.”
4. Electromyographic comparisons between clenching, swallowing and chewing in jaw muscles with varying occlusal parameters. Isabel Moreno 1, Teresa Sanchez 2, Ignacio Ardizone 3,
Fernando Aneiros 4, Alicia Celemin 2
5. Association between rhythmic masticatory muscle activity during sleep and masticatory myofascial pain: a polysomnographic study. Rossetti LM, Pereira de Araujo Cdos R, Rossetti PH, Conti PC. J Orofac Pain. 2008 Summer;22(3):190-200.
6. Sleep Bruxism: Validity of Clinical Research Diagnostic Criteria in a Controlled Polysomnographic Study. G.J. Lavigne, P.H. Rompre and J.Y. Montplaisir; J DENT RES 1996 75: 546
7. Principles and Practice of Sleep Medicine. Edited by: Meir H. Kryger, MD, FRCPC, Thomas Roth, PhD, and William C. Dement, MD, PhD, ISBN: 978-0-7216-0797-9
8. Aggravation of Respiratory Disturbances by the Use of an Occlusal Splint in Apneic Patients: A Pilot Study. Yves Gagnon, DMD, MSca/Pierre Mayer, MDb/Florance Morisson, DMD, PhDc/Pierre H. Rompr’e,MScd/Gilles J. Lavigne, DMD, MSc, PhDe. The International Journal of Prosthodontics, Volume 17, Number 4, 2004
9. AADSM: “Obstructive sleep apnea frequently goes undiagnosed because people often mistaken the serious sleep disorder for snoring. About half of loud snorers have some form of sleep apnea.”