Role of Orthopantomogram in Unexplained Earache

Abstract

Earache is one of the most common symptom for a patient to visit ENT doctor. It poses difficulty to diagnose the root cause when ENT examination is normal and still the pain persists, hence many a times patients are presumed to have psychosomatic element. While evaluation of earache dental status is often overlooked. 93 such patients of persistent earache with normal ENT examination were evaluated. In 70 of these patients the earache was attributed to either absent, unerupted or obliquely positioned upper or lower last molars which was confirmed by Orthopantomogram.

Introduction

Orthopantomogram (OPG) is a panoramic film of facial structures that includes maxillary and mandibular arches, teeth and supporting alveolar bone. It gives important information of anomalies in the number, position, anatomy of teeth and impacted third molars. Being a single image it is easier to explain and counsel the patient about the cause of earache.

With misaligned bite (malocclusion) or missing teeth your muscles must work harder in order to bring your teeth together for multiple functions like speaking or chewing. The constant contraction to provide the proper bracing support of the jaw against the skull lead to fatigue of masticatory muscles which ultimately exhaust and become shortened and stiff. This may result in painful muscle spasms and pull the jaw joints out of alignment [1]. These also cause microtrauma and tenderness at Temporo mandibular joint. Because of the shared innervation via branches of fifth nerve, there is referred otalgia. Consequently, any signals sent through this nerve can affect both the muscles of the jaw joint and those of the ear. In this study special attention to dental status was given and since ENT examination was normal the OPG was done to confirm the diagnosis.

Methodology

This study was conducted in the Department of ENT at Choithram Hospital and Research Centre, Indore between September 2016 and August 2017. This was retrospective analysis of 93 patients in the age group of 18–55 years who had clinically normal ENT but persistent earache. 70 of these had positive radiologic findings in OPG. Both males and females were included in the study. Earache was moderate to severe in intensity. There were no associated co morbidities like cervical spine problems or craniofacial abnormalities. Styloid process was not palpable on either side. Considering no obvious ENT cause, dental status was evaluated. Dental evaluations included position of upper and lower last molars, unerupted molars, obliquity of mouth opening (Fig. 1), occlusion and eliciting tenderness of masseter, temporalis and pterygoid muscles. Infectious causes like periapicitis, periodontitis, dental carries were excluded from the study. Clinical findings were confirmed by OPG.

Fig. 1.

Showing unerupted last lower molar with obliquity of mouth opening

Results

Out of 70 patients who had positive findings on OPG, 21 patients had obliquely placed last molars) (Fig. 2) (12 patients-lower, 9 patients—upper, 16 patients had unerupted molars (Fig. 3), 22 patients had asymmetry of teeth in two jaws (Fig. 4) while 11 patients had reduced retromolar space (Fig. 5). Majority of patients were females. These patients responded well to analgesics, muscle relaxants, topical analgesic gels. Suitable cases were referred for appropriate dental treatment.

Fig. 2.

Image showing obliquely placed last lower molars

Fig. 3.

Image showing unerupted left last lower molar impinging on nerve

Fig. 4.

Image showing malocclusion

Fig. 5.

Malocclusion with reduced retro molar space on left side

Discussion

This study evaluates missed causes of earache in patients with normal ENT examination. Thorough dental examination should be done to look for dentition status as this is one of the commonest causes of referred otalgia. Dental mal alignment can lead to unstable bite and frequent earache. Lateral or obliquely placed molars can impinge on inferior alveolar nerve leading to severe pain.

As the third molars are the last to erupt, there is often not enough jaw space for them to fully come through. Therefore they may only partially erupt into the mouth or not come through at all. When there is enough room, they will come through into the mouth normally and act as any other tooth. A tooth is described as impacted if it is blocked from erupting into the mouth fully. Thus it will lie atan angle instead of being upright, remaining tipped against the tooth in front of it [2].

OPG is one such investigation which gives complete information about dental status, retromolar space and proximity of tooth root to inferior alveolar nerve. Advantage of OPG is that it gives broad coverage of facial bones and teeth, low patient radiation dose, convenience of examination of the patient, useful in patients unable to open their mouth, short time required and in patient counselling and feedback [3–5].

Conclusion

Many cases of earache with normal ENT examination are attributed to dental cause like unerupted or partially erupted, obliquely and laterally placed lower and upper third molars which are often missed on routine ENT examination. Hence care should be taken to assess dental status while doing ENT examination. OPG is very useful tool that points to the probable dental etiology in a single panoramic image.

Authors’ Contribution

SP has contributed in data collection and preparation of manuscript. RA and SM have contributed to the concept and designing of manuscript. SN and AS have revised the manuscript.

Compliance with Ethical Standards

Conflict of interest

None.

Ethical Approval

Since this is retrospective study of data, ethical approval not required.

Informed Consent

Informed consent was obtained from all individual participants included in the study.