Tinnitus

Indhold:
Hvad er tinnitus?
Hvordan opstår tinnitus
Komplikationer.
Hvordan undgår man tinnitus?
Høreapparat.
Behandling.
Laserklinikkens behandling af tinnitus.
Teorien bag Laserklinikkens behandling af tinnitus.

Artikel: Low level laser therapy of tinnitus - a case for the dentist? Jan Tunér DDS, Swedish Laser-Medical Society


Hvad er tinnitus?
Tinnitus kan have mange former og kan opfattes som både susen, ringen, hylen, hvisken, knitren, summen m.m. Lyden kan være konstant eller periodevis, enslydende eller pulserende. Mange har oplevet at have tinnitus i nogle timer eller måske nogle dage - f.eks. efter at have været til en koncert eller lignende - men op mod 10 % af befolkningen (ca. 500.000 mennesker) menes at lide af kronisk tinnitus i større eller mindre grad. En del af disse er endog meget plaget af tinnitus'en i deres hverdag.
Tinnitus eller øresusen kan defineres som opfattelse af lyd, der ikke er genereret af omgivelserne. Lyden kan derfor ikke høres af andre end én selv.

Hvordan opstår tinnitus?
Tidligere mente man at tinnitus direkte skyldtes beskadigelse af sansecellerne i det indre øre, men de senere år har forskning vist, at der er flere årsager, eventuelt i kombination.

Alle har en naturlig baggrundsstøj i deres høresystem, som normalt ikke høres fordi den undertrykkes i en underbevidst del af hjernen. Det svarer lidt til, at lyden af f.eks. bølger på en strand dårligt opfattes, fordi den er "ufarlig" og undertrykkes, hvorimod man altid vender hovedet efter en ambulance eller et barn der græder, da disse lyde underbevidst signalerer "fare" og derfor bliver forstærket.

Tinnitus opstår, når den underbevidste del af hjernen ved en fejl opfatter den naturlige baggrundsstøj som "fremmed" og farlig og forstærker den i stedet for at undertrykke den. Denne fejlforstærkning hænger ofte sammen med nedsat hørelse og tinnitus opleves ofte som følge af en række omstændigheder, der kan give hørenedsættelse:
Tilstoppet øregang som ved ørevoksprop eller fremmedlegeme.
Skader på trommehinde hvor der er punktering eller infektion.
Skader eller betændelser i mellemøre, mellemørebetændelse eller skade på de små mellemøreknogler.

Derudover kendes en række andre årsager til tinnitus:
* Stress og træthed (som kan forstærke tinnitus).
* Forhøjet blodtryk.
* Åreforkalkning i hjernen eller blodprop i hjernen.
* Blodmangel.
* Svulster (oftest godartede) på hørenerven eller i selve hjernen.
* Overdosis af hovedpinepiller indeholdende acetylsalicylsyre.

Komplikationer
Tinnitus skyldes sjældent en alvorlig, helbredstruende lidelse og har sjældent komplikationer ud over den gene, støjen udgør. Man bliver ikke døv af at have tinnitus, men lidelsen opleves som nævnt ofte sammen med en hørenedsættelse.

Omvendt oplever en del tinnituspatienter, at de har oversensitiv hørelse (hyperacusis), hvor alle lyde virker støjende og generende. Mekanismen for dette ligner den for kronisk tinnitus og behandlingen er ens.
Af de, som lever med kronisk tinnitus, er en del kraftigt generet af den konstante larm. Det kommer ofte til udtryk som stort søvnbesvær og manglende evne til at koncentrere sig. For nogen er det umuligt at arbejde. En så voldsom tinnitus kan give anledning til fortvivlelse, angstanfald og depressioner og perioder med brug af lægeordineret sovemedicin og eventuelt antidepressiv medicin kan blive nødvendige.

Hvordan undgår man tinnitus?
Da en hørenedsættelse ofte findes sammen med tinnitus og formentlig kan fremprovokere og forstærke tinnitus, er det vigtigt at beskytte sin hørelse bedst muligt.
Såfremt der er symptomer på sygdom i ørerne (smerter, propper, svimmelhed, pludselig hørenedsættelse eller lydoverfølsomhed), er det fornuftigt at få en læge til at undersøge og vejlede.

Brug altid høreværn, når du udsætter dig selv for høje lyde, høj musik, arbejde med maskiner, fyrværkeri og andre eksplosioner osv.

Høreapparat
Lider man af tinnitus, er det vigtigt at få foretaget en grundig høretest og få korrigeret en eventuel hørenedsættelse med et høreapparat, da dette ofte har en dæmpende effekt på tinnitussymptomer. Har man i stedet oversensitiv hørelse (hyperacusis), kan det være nødvendigt at benytte ørepropper eller anden høreværn.

Behandling
Tinnitus forsvinder ofte af sig selv efter kortere eller længere tid.
Hvis man oplever tinnitus, der ikke forsvinder af sig selv inden for kort eller nogen tid, bør man få det undersøgt for at finde en eventuel årsag til den opståede tinnitus. Der er dermed en mulighed for at fjerne årsagen. 
Kronisk tinnitus kan være svær at behandle. Der findes ingen mirakelkur, der kan fjerne tinnitus helt, men der er dog på det seneste kommet nye muligheder, som kan reducere generne ved plagsom tinnitus.

Hidtil har behandlingen af voldsom tinnitus været mere eller mindre begrænset til gode råd såsom at undgå total stilhed (f.eks. er stille baggrundsmusik godt når man skal sove) og desuden brug af en såkaldt "masker", som er et apparat, der udsender en svag brusende lyd, der overdøver tinnitus'en men er mere behagelig end denne.
At undgå stilhed er stadig et godt råd, men i stedet for at overdøve tinnitus'en ind i mellem, har man fundet ud af, at det på længere sigt er bedre at "vænne sig" til tinnitus'en. Dette tilstræber man med "genoptræningsterapi".
Derudover er der genoptræningsterapi (Tinnitus Retraining Therapy, TRT), som er en behandlingsmetode, som går ud på at vænne sig til tinnitus både på det bevidste og underbevidste plan. Dette opnås gennem en længere træningsproces (op til to år), hvor man lærer om, hvad tinnitus egentlig er. Dette hjælper til at lære bevidst at vænne sig til og ignorere den lyd, man hører og efterhånden også "genoptræne" de underbevidste dele af hjernen til igen at undertrykke lyden - i stedet for fejlagtigt at forstærke den som beskrevet ovenfor. Denne tilvænning kan i princippet føre til at tinnitus forsvinder helt. I praksis er processen langvarig og fjerner sjældent tinnitus helt, men støjen falder oftest til et niveau, hvor den næsten eller slet ikke er til gene for personen. Mange hørecentre tilbyder tinnituskurser, der lægger sig tæt op ad principperne for TRT. 

Ménière og Tinnitusforeningen http://www.mtf.dk/, hvor du kan få mere at vide om tinnitus og genoptræningsterapi.

Laserklinikkens behandling af tinnitus:
Orthomolekylær behandling (kosttilskud). Laserbehandlingen er baseret på en række videnskabelige undersøgelser, som har vist effekt på tinnitus.
Forudsætningen er, at de kendte årsager til tinnitus er behandlet, og behandlingen begrænser sig til kronisk tinnitus, dvs støjskade forårsaget tinnitus.

Behandlingsmetode:
Kort fortalt er behandlingen: stimulation og afspænding som laseren medfører. Der laserbehandles direkte ind i øret, med retning i mod det indre øre. Der kan behandles, indtil der mærkes en reaktion i form af uro og varme i øret – i nogle tilfælde høres en fiskekutter-lyd. Der behandles altid i begge ører med laser, da Tinnitus ofte findes i begge ører.
Behandlingen fortages i første uge 1 - 2 gange, og i anden uge gentages behandlingen samme dage og siden fortsættes, indtil der kommer en ændring i støjen. Falder støjen, eller bliver den mere rolig kan der prøves at behandle flere gange om ugen. Forværres støjen skal der holdes en pause indtil den er faldet tilbage igen, derefter behandles der igen, men nu med længere tid mellem behandlingen.

Forundersøgelse:
Øre undersøgelse
Høreprøve
Lab: Hgb, SR, B12, Ekg, BT, lungefunktion samt mineral undersøgelse.
Behandling:
1: LASER lav energi: behandles x 2 ugentligt med:
Multilaser (GaAlAs 808 nm 9,0W) begge øre x 15 min.
Tinlaser (GaAlAs 820 nm 250 mW) 30 min begge øre.
Behandles i alt 10 gange, gentages med 5 behandlinger efter 2 mdr. gentaget 2-3 gange 

2: Antioxidanter: tages under hele behandlingen
Højdosis multivitamin, Vitamin C som ascorbat 2-3,5 gr. dgl., E-vit 400 IE, Q10-vitamin 50 mg dgl.
B12-vitamin, Green tea (antioxidant).

Høreprøve før og efter hver behandlingsrunde.

Forventet resultat:
Reduceret tinnitus samt forbedret høreevne, let forbedret efter 6 mdr., endeligt resultat efter 12 mdr.
Normalt vil de første 5-10 behandlinger vise om laseren har virkning. Antallet af behandlinger før tinnitus er forsvundet varierer fra person til person. I nogle tilfælde forsvinder støjen efter 15-20 behandlinger, i andre først efter 30-50 behandlinger. Tyske behandlingsresultater og undersøgelser viser, at der i nogle tilfælde kan gå helt op til 1-3 år før tinnitus er behandlet.
Vores foreløbige resultater af behandling af Tinnitus med laser viser, at det er vigtig at finde en rytme i behandlingen. Behandles der for hyppigt kommer der enten en kraftig overreaktion, der forværrer tinnitus (måske fordi cellerne stresses af behandlingen) eller også sker der ingenting. Behandles der for lidt, sker reaktionen meget langsom eller udebliver helt.
Samling af behandlingsdata og undersøgelser viser, at resultaterne fordeler sig sådan, at ud af en gruppe på 10 patienter, med et behandlings gennemsnit på 15-20 behandlinger, vil resultatet  typisk være sådan at 1-2 personer ikke har nogen virkning af behandlingen, 3-4 patienter vil få delvis bedring, typisk ro om natten. 3-4 patienter vil få kraftig forbedring, kun svagt høre Tinnitus og 2-3 patienter vil få 100 % heling af Tinnitus.
En bivirkning af behandlingen er, at patienter med nedsat hørelse i flere tilfælde har fået genoprettet hørelsen! Samlet har ca. 2/3 af gruppen fået hel eller delvis virkning af behandlingen

Teorien bag Laserklinikkens behandling af tinnitus:
Dr. Jan Tunér, svensk tandlæge mener, at tinnitus kan være et tandlægeproblem og at karakteren af den uønskede lyd ofte kan ændres ved LLLT (lavenergilaser behandling), hvor man behandler spænding i ansigtsmuskler og regulerer kæbestilling.
Den Czekiske duo Tejnska and Prochazka [15] har præsenteret arbejde om LLLT laser behandling (see Clinixperience No. 4/2000 og [15]) som viser deres nye fund baseret på lang tids studie på patienter, der er generet af tinnitus.
Deres behandlingsmetode for tinnitus er at give massive irradiation af meatus og mastoideus med store doser af laserenergi, som vist ved eksperimenter af dr. Lutz Wilden i Tyskland.
Lutz Wilden, hvis arbejde og resultater af laserbehandling af sygdomme i det indre øre har bevirket at US Food and Drug Administration (FDA - den amerikanske sundhedsstyrelse) har tilladt laserbehandling for tinnitus.
Det Czechiske GaAlAs laserapparat Maestro har modtaget FDA´s godkendelse for tinnitus behandling.: ” FDA: 510(k) was issued on september 12, 2002, number K023026, application approved on "treatment of subjective tinnitus not caused by intracranial pathologies such as tumors or AVM`s"
Wilden [11] [12] har siden anvendt en anden metode, hvor dosis er blevet forøget betydeligt. En opstilling af en HeNe laser og 3 kraftfulde GaAlAs laser er blevet brugt, dækkende et stort areal over og rundt om øret i en ikke-kontakt metode. Dosis mellem 3.000 and 5.000 J er givet i hver behandlings session. Laser er blevet brugt som en monotherapy. Mere end 800 patienter er blevet behandlet med dette koncept og positiv effekt er rapporteret - selv for vertigo (svimmelhed). Nyligt opståede skader i "the disco generation" er lettere at behandle end kroniske tilstande. I et separat studie har Wilden [13] rapporteret forbedring af hørekapaciteten hos disse patienter. Vist ved audiometri (høreprøve).

Dr. Jan Tunérs konklusion.: Der er grund til at formode, at der er grupper af tinnituspatienter (og også svimmelhed), som har et problem med tyggemuskler (primary Crano-temporo-Mandibular Dysfunction) og at tinnitus fornemmelsen er et sekundær fænomen hos nogle af disse patienter.
Størrelsordenen af disse patientgrupper er ukendt, da CMD relationen sjældent er diagnosticeret eller behandlet. Korrelation mellem Ménières sygdom og CMD ser ud til at være hyppigere forekommende end korrelation mellem et isoleret tinnitus problem og CMD.
Nogle af disse patienter i den nævnte undergruppe kan skifte intensitet eller styrke af deres tinnitus ved at åbne munden. I nogle tilfælde selv ved at skifte position af hoved. Laserbehandling af musklerne bevirker, at tinnitusfænomenet kan ændre karakter. Dette giver en mulighed for en tidlig diagnose af typen af tinnitus. Det er ikke udsædvanligt at tinnitusfornemmelsen forsvinder midlertidigt efter laserbehandling. Gentagende laserbehandlinger kan holde disse patienter fri af tinnitus og også gøre patienten mere opmærksom på spændinger i musklerne.
   

Artikel ( på engelsk):

Low level laser therapy of tinnitus - a case for the dentist?

Jan Tunér DDS, Swedish Laser-Medical Society (www.laser.nu)

ABSTRACT:
Tinnitus is a debilitating condition with an increasing incidence, especially among the young generation, due to intensive sound levels at concerts and in headsets. It is, however, not solely a problem of the modern world. The condition is described in papyrus documents dating back 600 BC. Some famous historic persons have suffered from tinnitus, such as Martin Luther, Jean-Jaques Rousseau and Ludwig van Beethoven.
It is estimated that roughly one person in ten is affected by tinnitus of some degree.
The origin of tinnitus is controversial. It is claimed that tinnitus is located in the inner ear but also that it actually is situated in the brain cortex, as evidenced by PET-scanning.
It is reasonable to believe that the condition can have several origins and that one of these then is of interest to the dentist.

Low level lasers have been claimed to have a therapeutic effect on tinnitus and vertigo. In these cases the irradiation has been directed towards the cochlea.
Low level laser therapy (LLLT) is also reported to be useful in the treatment of temporo-mandibular disorders (TMD). Furthermore, some patients are cured from their tinnitus when a proper TMD therapy has been performed. It now also appears that low level lasers can be used to advantage in the treatment of TMD-related tinnitus, and without actually irradiating the inner ear LOW LEVEL LASERS Since the beginning of the 80's low level lasers have become increasingly popular as an additional treatment possibility in many professions, such as chiropractors, naprapaths and physiotherapists but not so much in traditional medicine and dentistry.
In spite of more that 100 positive double blind studies there remains a skeptical attitude. In dentistry alone, more than 90% of the published studies show positive results. It is true that several studies have failed to show any result, but it is not uncommon for such studies to contain serious flaw [1]. And it is not to be expected that any dosage or any wavelength of low level laser will produce a biological response.

Low level lasers are generally in the visible - near visible range of the spectrum. The most common types are HeNe (633 nm), InGaAlP (630-685 nm), GaAlAs (780-870 nm) and GaAs (904 nm). Power output in the beginning ranged from 1-10 mW. With the advent of less expensive diodes the power has increased considerably and GaAlAs lasers are now available with power of even 1 000 mW (1 Watt). Increased dosage and power density have proven to be important and the clinical results have consequently been improved. Suitable dosage varies depending on the condition and the depth of the target tissue, but generally 4-20 J/cm2 are applied. Red laser light is optimal for superficial conditions such as mucosa and skin whereas infrared is better for pain and deeper lying conditions because of its superior penetration.

Biological responses of cells to laser irradiation are suggested [2] to occur due to physical and/or chemical changes in photoacceptor molecules, components of the respiratory chain like cytochrome c oxidase and NADH-dehydrogenase. Hypotheses about primary mechanisms at the interface of laser irradiation and tissue are redox properties alterations, NO release, superoxide anion reactions, singlet oxygen production and local transient heating of chromophores. Further, secondary processes are triggered where the mechanisms are performed "in the dark". Thus, distant effects can be obtained far from the irradiated area. The redox-regulation mechanism may explain the positive effect of tissues characterized by acidosis and hypoxia LOW LEVEL LASER OF TINNITUS - THE LITERATURE Low level laser therapy (LLLT) has been suggested as a possible therapy for tinnitus. Several studies have used Ginkgo biloba infusions in combination with LLLT, the former being a widespread but not well documented therapy for tinnitus. The number of studies is few and they will be briefly described in the following
Witt [3] is one of the pioneers in this field, but to the knowledge of the author his results have not been published in any peer-review journal. Witt combines infusion of Gingko biloba (Egb 761, 17.5 mg dry extract per 5 ml amouple)) and laser. This may be a favorable combination but an evaluation of the contribution of the laser is not possible. More than 500 patients have been treated since 1989 and Witt claims that more than 60% of the patients have reached a considerable or total relief. The laser used is a combination of HeNe 12 mW/GaAs 5 x 10 mW. Treatment technique not stated.

Swoboda [4] did not find any significant effect of Gingo/laser. However, the ginkgo infusion used was at a homeopathic level (D3 = 1:1000 dilution), acc. to Witt.

Partheniadis-Stumpf [5] also failed to find any effect from the combined ginkgo (6 ml Tebonin) infusion and laser. However, the laser was applied at a distance of one cm above the mastoid. The non-contact mode reduces penetration considerably and the mastoid is not ideal for reaching the inner ear.

Plath [6] treated 40 tinnitus patients with 50 mg Ginkgo biloba. 20 patients received sham laser irradiation, 20 real lasers. A HeNe 12 mW/GaAs 5 x 15 mW GaAs laser was used, irradiation procedure approximately the same as for Partheniadis-Stumpf. In this study, 50% of the patients reported a reduction of the tinnitus of more than 10 dB, compared with 5% in the control group, in both self-assessment and audiometric findings.
A similar study has been performed by von Wedel [7]. 155 patients were treated with Ginkgo infusion (5 ml Syxyl D3) and laser. The outcome was negative. No information about the type of laser, treatment technique or dosage is given, making an evaluation impossible.
Shiomi [8] has investigated the effect of infrared laser applied directly into the meatus acusticus, 21 J, once a week for 10 weeks. The result of this non-controlled study is as follows: 26% of the patients reported improved duration, 58% reduced loudness and 55% reported a general reduction in annoyance.
The same author [9] has also examined the effect of light on the cochlea, using guinea pigs. Direct laser irradiation was administered to the cochlea through the round window and the amplitude of CAP was reduced to 53-83% immediately after the onset of irradiation. The amplitude then returned to the original level. The results of this investigation suggest that LLLT might lessen tinnitus by suppressing the abnormal excitation of the 8th nerve or the organ of Corti.

More or less the same parameters were used in a controlled study by Mirtz [10] but in this case there was no significant effect.

Wilden [11] [12] has applied a different method where the dose has been increased considerably. A set consisting of one HeNe laser and three powerful GaAlAs lasers is used, covering a large area over and around the ear, in the non-contact mode. Doses between 3.000 and 5.000 J are given each session. Laser is applied as a monotherapy. More than 800 patients have been treated with this concept and positive effects are reported, even for vertigo. Recent injuries in "the disco generation" are more easily treated than long-term chronic conditions. In a separate study [13] Wilden reports improvement of the hearing capacity of these patients, as evaluated by audiometry.

Beyer [14] has performed a very exact ex-vivo laser penetration study. Based on these findings it was possible to calculate the energy needed to obtain a dose of 4 J/cm2 in the cochlea itself. 30 patients were treated five times within 2 weeks. One group was irradiated with 635 nm diode laser, the other with 830 nm diode laser. By self-assessment around 40% of the patients reported a slight to significant attenuation of the tinnitus loudness of the irradiated ear. This study has been followed by a double blind study.

Prochazka [15] has evaluated the effect of combined Egb 761 Ginkgo infusion and laser in a double blind study. 37 patients were divided into three groups. One group had Egb 761 only, one Egb761 and placebo laser, one Egb761 and real laser, 830 nm. The results in the three groups were as follows: no effect 29/26/19, less than 50% relief 44/48/29, more than 50% relief 18/26/36, and no more tinnitus 9/0/26. Irradiation was performed over the mastoid and over the meatus acusticus, twice a week, 8-10 sessions, total 175 J.

Rogowski [16] divided a group of 32 tinnitus patients into one group receiving LLLT and one receiving a placebo procedure. Dose, wavelength and treatment technique not stated in the available English abstract. The effect was evaluated through VAS. Within the patient group transiently evoked otoacoustic emissions (TEOAE) were measured before, during and after therapy. No significant difference between laser and placebo was found in annoyance or loudness of the tinnitus and in changes of TEOAE amplitude. These results indicate that there is no relationship between the effect of low-power laser and changes in cochlear micromechanics.

A few other indications in otorhinolaryngology have been treated with low level lasers, even with intravenous irradiation. [17-20]

It is obvious that the available literature on laser therapy of tinnitus is scares and ambiguous. Some studies have used a combination of Ginkgo and laser, others laser as monotherapy. Differences in wavelengths, pulsing, dosage and treatment technique makes a firm evaluation impossible. However, the positive results reported in some studies do merit attention and further research. Recent clinical experience also suggests that the doses necessary for successful outcome of the therapy have to be increased considerably. Tinnitus is a grave condition, sometimes leading to suicide. It is also an increasing problem and the existing treatment modalities offered to tinnitus patients are not very effective. Young persons suffering from acoustic chocks (concerts, discos) can be more successfully treated with laser therapy. Understandably enough, a long standing condition in elderly persons is a severe condition taking 10-20 sessions to influence.

LASER THERAPY OF TMD The following is an account of some studies published in the field of low level laser therapy for TMD.
Hansson [21] studied the effects of GaAs laser on arthritis of the temporo-mandibular joint. The author stresses that lasers are not an alternative to conventional treatment, but that it seems possible to reduce healing periods and more quickly reduce inflammation
Bezuur and Hansson [22] treated a group of 27 patients suffering from long-term problems related to TMD with a GaAs laser. The treatment was administered over the joint on five consecutive days. 80% of the 15 patients with arthrogenous pain experienced total pain relief. The maximum jaw-opening ability increased during the treatment period, and continued to increase during the year that the group was monitored. The group suffering from myogenic problems also improved, both in terms of pain and jaw-opening ability. The effect here was, however, much lower. As the muscles were not treated, it is assumed that this group also had undiagnosed arthritis. The reduction of joint sounds may possibly have been due to an increase of metabolism in articular cell structures, e.g. an activation of the synovial membrane, producing more synovial fluid.

Eckerdal [23] reports on the clinical experience of a 5-year non-controlled study of perioral neurapathias. The treated diagnoses were trigeminal neuralgia, atypical facial pain, paresthesias, and TMD pain. Of these diagnoses, the TMD pain group was the most successful one. At the end of treatment, 73% of the patients (N = 40) had a good response, at six months still 73%, and at one year 70%. 10 J/cm2 was applied to the joint over 4-8 sessions.

In a study comprising 75 cases, Bradley [24] found LLLT effective as a monotherapy when treating acute joint pain (less than eight weeks duration). In more chronic cases, without bone changes on X-ray, LLLT was used as an adjunct to splints and the like. In osteoarthritic cases, LLLT can be almost as useful as intra-articular steroids.

Bradley [25] used GaAs laser acupuncture when treating a small group of patients suffering from TMJ pain dysfunction syndrome who had not responded to treatment with a bite splint or psychotropic medicine. Needle acupuncture was used in a comparative group. Both types of acupuncture can be studied with thermography. Biostimulation was observed to yield vascular effects which locally resemble the vascular effects achieved with needle acupuncture, although it takes more time for laser stimulation to take effect. Both forms of acupuncture were more effective on known acupuncture points than on randomly chosen points. St 6 was used throughout as a "known acupuncture point".

Kim [26] divided a group of 36 patients with maxillary joint problems into three therapy groups. The patients were treated with bite splints, GaAlAs laser treatment, or laser acupuncture. The treatment results were compared after two and four weeks with a check on status before treatment. The following conclusions were drawn: The patients' subjective discomfort was reduced in both the bite splint and laser treatment groups. The improvement in the laser group was much greater than in the bite splint group. Clinically observable symptoms showed a significant reduction in all groups, but the group treated with laser light responded faster to treatment than the other groups. EMG activity gradually decreased in all the groups - and without any great difference between groups. Laser treatment had more beneficial effects than bite splints, while laser acupuncture produced the poorest results.

Lopez [27] treated a group of 168 patients with problems related to TMD with a combination of bite splints and HeNe laser. An obvious improvement could be observed in 52 of the patients after a single treatment. After ten treatments, 90% of the patients had improved. No further improvement was brought about in the other 10% by administering further treatments. The laser treatment was given directly over the maxillary joint - 6 mW for five minutes (1.8 J). The extent of healing was inspected using a tomographic X-ray before treatment and after six months. At that point, healing had advanced to a stage usually seen after 12 to 18 months when only a bite splint is used. In a group of 88 patients with pains in the jaw muscles, pain was alleviated for up to six hours, but without lasting results. The author concluded that HeNe lasers are effective as a complementary method to bite splints when treating arthrosis and arthritis, but that this wavelength is not optimal for myogenic pain.

Hatano [28] used a GaAlAs laser to study the effect on palpation pain in 15 patients with TMD. A 30 mW laser was used for 3 minutes (5.4 J) in the area of one temporo-mandibular joint. The other side served as control. Palpation score was estimated directly after irradiation and at 20, 40, and 60 minutes after irradiation. There was a significant decrease in palpation pain with better values at 20, 40, and 60 minutes than directly after irradiation.

Bertolucci [29] compared two groups of patients (16+16) receiving physical therapy for mandibular dysfunction. One group received sham irradiation, the other GaAs during three weeks. The results were as follows (treatment group/placebo group): change in pain 40.25/1.56; change in vertical opening 1.35/-0.05; change in left and right deviation 3.78/0.62.

Interleukin-1b in the synovial fluid is associated with TMD pain [30]. In a study by Shimizu [31], GaAlAs laser light influenced the production of this substance.

Ivanov [32] treated 109 patients with temporomandibular joint arthritis and arthrosis with an HeNe laser (12 mJ/cm2, 3-7 treatments). 89% of the patients reported clinical improvement.

In a double blind study by Sattayut [33], the higher doses (20 J per point, 300 mW) were clearly more effective than 4 J and 60 mW. In this study GaAlAs was used as monotherapy. Following a period of 2-4 weeks after therapy (3 sessions in one week) there was an average of 52% reduction of pain as assessed by SSI pain questionnaire.

CMD, TMD, LLLT AND TINNITUS It has been know for decades that patients with temporo-mandibular joint dysfunction (TMD) and crano-mandibular disorders (CMD) also may have tinnitus problems, and that there is a connection between the two
In a book by Myrhaug [34], the author underlines the fact that there are two muscles in the inner ear which are innervated by two facial nerves. M. tensor tympani are innervated by n. trigeminus and m. stapedius is innervated by n. facialis. Intensive action in the masticatory muscles could therefore influence these two small muscles as well and thereby cause the tinnitus sensation.

Bjorne [35] compared a group of 31 patients suffering from Ménière's disease with a control group, matched for sex and age. The patients in the Ménière group had statistically significant more signs of crano-mandibular disorders, such as tenderness to palpation upon the masticatory muscles, of the temporo-mandibular joint, upper part of the trapezius in the area of the atlas, the axis and the third cervical vertebra.

In a second study by Bjorne [36] 24 of the 31 patients from the previous study were compared with 24 control subjects regarding the frequency of signs and symptoms of cervical spine disorders. Symptoms of cervical spine disorders as head and neck/shoulder pain, and signs as limitations in side-bending and rotation movements were more frequent in the patient group as well as tenderness to palpation of the neck muscles. 39% of the Ménière patients could influence their tinnitus; both sound level and pitch, by protrusion or lateral movement of the mandible or by clenching their teeth. 75% of the patients could trigger their attacks of vertigo by extension, flexion or side-rotation of the head and neck.

A correlation between tinnitus and tension of the lateral pterygoid muscle has also been found [37]. Further correlation between signs and symptoms of TMD and tinnitus is indicated in studies by Rubenstein [38] and Ciancaglini [39].

Wong [40] reports that the styloid process and its attachments are often the center of TMD problems and that no less than 11 symptoms have been observed in connection with soft tissue lesions in this region, one of them being tinnitus. The muscular symptoms are suitable for low level laser therapy acc. to the authors.

DISCUSSION There is reason to believe that a subgroup of the tinnitus (and vertigo) patients actually has a primary crano-temporo-mandibular dysfunction problem and that the tinnitus sensation is a secondary phenomenon. A greater awareness of this possibility and a closer cooperation between otorhinologists and dentists would probably reduce the problems of the patients in this subgroup. The size of this group is unknown, since the CMD relation is seldom diagnosed, nor treated. The correlation between Mènière's disease and CMD seems to be more frequent than the correlation between an isolated tinnitus problem and CMD.
Some of these patients in the mentioned subgroup can change the intensity or pitch of their tinnitus by clenching or opening their mouth wide and in some cases even by changing the position of their head. Irradiating a muscle involved in the creation of the tinnitus phenomenon can alter the character of the tinnitus. This offers a possibility of an initial diagnosis of the type of tinnitus. It is not unusual for the tinnitus sensation to disappear temporarily after laser irradiation. Repeated irradiation can keep the patient free of tinnitus and also make the patient more aware of the hypertension in the muscles.
CMD/TMD is a very common condition and the suggested treatment modalities are multifold. Occulsal splints and elimination of occlusal interferences are standard procedures but the scientific documentation of these, and other treatment modalities are still poor, although the clinical experience seems to verify their effectiveness.
The concept of treating tinnitus and vertigo patients through occlusal stabilization is not new but so far not very much explored. Adding low level laser irradiation to this therapy is even less explored and there is very little research. The objective of this article is not to give precise recommendations about treatment procedures but rather to put the light on the possibility for the dentist to improve the quality of life of many vertigo and tinnitus patients and that the dentist could play an important role in this treatment. Further research is warranted References [1] Tunér J, Hode L: It's all in the parameters: A critical analysis of some well-known studies on Low-Level Laser Therapy. J Clin Laser Med Surg. 1998; 16(5):245-248.
(Extended version on http://www.laser.nu/lllt/LLLT_critic_on_critics.htm)
[2] Karu T. Mechanisms of low-power laser light on cellular level. In: Lasers in Medicine and Dentistry. Ed: Simunovic Z. 2000; European Laser Medical Association. ISBN 953-6059-30-4.
[3] Witt U, Felix C. Selektive photo-Biochemotherapie in der Kombination Laser und Ginkgo-Pflanzenextrakt nach der Methode Witt. Neue Möglichkeiten bei Innerohrstörungen. [Selective photo-biochemotherapy in the combination of laser and gingkoplan extracts acc. to the Witt method] (1989). Unpublished material.
[4] Swoboda R, Schott a. Behandlung neurotologischer Erkrankungen mit Gingko biloba Hevert, Hyperforat und Low-Power-Laser-Therapie. [Treatment of neurotologic diseases with Gingko biloba and low level laser therapy] Medizinische Akademie Erfurt. (1992)
[5] Partheniadis-Stumpf M, Maurer J, Mann W. Titel: Soft laser therapy in combination with tebonin i.v. in tinnitus. [in German)] Laryngorhinootologie 1993; 72(1):28-31
[6] Plath P, Olivier J. Results of combined low-power laser therapy and extracts of Ginkgo biloba in cases of sensorineural hearing loss and tinnitus. Adv Otorhinolaryngol.1995;49:101-4
[7] von Wedel H, Calero L, Walger M et al. Soft-laser/Ginkgo therapy in chronic tinnitus. A placebo-controlled study. Adv Otorhinolaryngol.1995;49:105-8
[8] Shiomi Y, Takahashi H, Honjo I, Kojima H, Naito Y, Fujiki N: Efficacy of transmeatal low power laser irradiation on tinnitus: a preliminary report. Auris Nasus Larynx 1997;24(1):39-42.
[9] Shiomi Y et al. [Effect of low power laser irradiation on inner ear] [in Japanese]. Pract Otol (Kyoto). 1994; 87: 1135-1140.
[10] Mirz F, Zachariae R, Andersen S E et al. The low-power laser in the treatment of tinnitus. Clin Otolaryngol 1999; 24: 346-354.
[11] Wilden L. The effect of low level laser light on innear ear diseases. In: Low Level Laser Therapy, Clinical Practice and Scientific Background. Jan Tunér and Lars Hode. Prima Books in Sweden AB (1999). ISBN 91-630-7616-0.
[12] Wilden L, Dindinger D. Treatment of chronic diseases of the inner ear with low level laser therapy (LLLT): pilot project. Laser Therapy. 1996; 8: 209-21210
[13] Wilden L, Ellerbrock D. Verbesserung der Hörkapazität durch Low-Level-Laser-Licht (LLLL). [Amelioration of the hearing capacity by low-level-laser-light (LLL)]. Lasermedizin. 1999; 14: 129-138.
[14] Beyer W et al. Light dosimetry and preliminary clinical results for low level laser therapy in cochlear dysfunction. Proc. Laser Florence '99.
[15] Prochazka M, Tejnska R. Comprehensive therapy of patients suffering from tinnitus. Proc. Laser Florence '99.
[16] Rogowski-M, Mnich-S, Gindzienska-E, Lazarczyk-B. [Low-power laser in the treatment of tinnitus -a placebo-controlled study] . Laser niskoenergetyczny w leczeniu szumow usznych-badania porownawcze z placebo. Otolaryngologia polska. [Otolaryngol-Pol]. 1999; 53 (3): 315-20
[17] Mishenkin N V et al. [Effects of helium-neon laser energy on the tissues of the middle ear in the presence of biological fluids and drug solutions]. [in Russian] Vest Otorinolaringol. 1990; 5: 18-21
[18] Bogomilskii M R et al. [Effect of low-energy laser irradiation on the functional state of the acoustic analyzer]. [in Russian] Vest Otorinolaryngol. 1989; 2: 29-34.
[19] Palchun V T et al. [Low-energy laser irradiation in the combined treatment of sensorineural hearing loss and Ménière's disease]. [in Russian] Vestnik Otorinolaryngol. 1996; 1: 23-25.
[20] Ribari O et al. [Closure of tympanic perforations with low-energy HeNe laser irradiation]. [in German] Acta Chir Academ Scient Hungariacae. 1980; 3: 229-238.
[21] Hansson T: Infrared laser in the treatment of craniomandibular disorders, arthrogenous pain. J Prosthetic Dentistry. 1989; 61: 614.
[22] Bezuur N J et al: The effect of therapeutic laser treatment in patient with cranomandibular disorders. J Cranomandib Disorders. 1988; 2: 83.
[23] Eckerdal A. Kliniske erfaringer fra et 5-års icke-kontroleret studie af low power laserbehandling af periorale neuropatier. [Clinical experiences from a 5 years non-controlled study of low power laser treatment of perioral neuropatias] [in Danish]. Tandlægebladet. 1994; 98 (11): 526-529.
[24] Bradley P F, Rebliini Z. Low intensity laser therapy (LILT) for temporomandibular joint pain: a clinical electromyographic and thermographic study. Laser Therapy. 1996; 1: 47
[25] Bradley P: Thermographic Evaluation of Response to Low Level Laser Acupuncture. Proc. Second Meeting of the International Laser Therapy Association, London Sept 1992. p 32.
[26] Kim, Ki-Suk and Kim, Young-Ku: Comparative study of the clinical effects of splint, laser acupuncture and laser therapy for temporomandibular disorders. J Dental College, Seoul Nat Univ. 1988: 1(12): 195.
[27] Lopez V. J: El laser en el tratiamento de las disfunciones de ATM. Revista de Actualidad de Odontoestomatologica Española. [The laser in treatment of TMD]. 1986; 35.
[28] Hatano Y: Lasers in the diagnosis of the TMJ problems. In: Lasers in dentistry. Eds. Yamamoto Y et al. 1989; p. 169-172. Elsevier Science Publishing B.V, Amsterdam
[29] Bertolucci L E, Grey T. Clinical analysis of Mid-laser versus placebo treatment of arthralgic TMJ degenerative joints. J Craniomandib Practice. 1995; 13 (1): 26-29
[30] Alstergren P et al. Interleukin 1ß in the arthritic temporomandibular joint fluid and its relation to pain, mobility and anterior open bite. Swedish Dent J. 1998; 2: 247.
[31] Shimizu N et al: Prospect of relieving pain due to tooth momement during orthodontic treatment utilizing a GaAlAs diode laser. SPIE Proc. 1995; Vol. 1984: 275-280.
[32] Ivanov A S. et al: Effect of Helium-Neon laser radiation on the course of temporomandibular joint arthritis and arthrosis. Stomatologiia (Mosk). 1985; 64: 81-82.
[33] Sattayut S. Thesis. St Bartholomew's and the Royal London School of Medicine and Dentistry. 1999. Professor P. Bradley.
[34] Myrhaug H. The theory of otosclerosis and Morbus Ménière (Labyrintine vertigo) being caused by the same mechanisms: physical irritants and otognathic syndrome. 1981. Bergmanns Boktrykkeri A/S, Bergen, Norway.
[35] Bjorne A, Agerberg G. Cranomandibular disorders in patients with Meniere's disease: a controlled study. J Orofacial Pain. 1996; 10 (1): 28-37.
[36] Bjorne A, Berven A, Agerberg G. Cervical signs and symptoms in patients with Meniere's disease: a controlled study. J Cranomandib Practice. 1998; 16 (3): 194-202.
[37] Bjorne A. Tinnitus aureum as an effect of increased tension in the lateral pterygoid muscle [letter]. Otolaryngol Head Neck Surg. 1993; 109: 969.
[38] Rubenstein B. Tinnitus and cranomandibular disorders - is there a link? [thesis]. Swed Dent J Suppl. 1993; 95
[39] Ciancaglini R, Loreti P, Radaelli G. Ear, nose and throat symptoms in patients with TMD: The association of symptoms according to severity of arthropathy. J Orofacial Pain. 1994; 8: 293-296.
[40] Wong E, Lee G, Mason T. Temporal headaches and associated symptoms relating to the styloid process and its attachments. Ann Academy of Medicine Singapore. 1995; 24: 124-128.


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