Augmentation of Therapeutic Efficacy of Extraction of Causative Teeth by Irrigation for Odontogenic Maxillary Sinusitis

Discussion

Odontogenic maxillary sinusitis (OMS) is a common disease in oral surgery and otolaryngology, and currently the most common evaluation method is the Lund-Mackay (L-M) score on sinuses CT (6). In this method, CT findings regarding maxillary sinuses, frontal sinuses, anterior ethmoid sinuses, posterior ethmoid sinuses, and sphenoid sinuses are classified into three categories: no opacity, partial opacity, and complete opacity. Therefore, it is difficult to make a detailed evaluation on CT images. To overcome this problem, we created a five-point scale to evaluate the extent of maxillary sinus mucosal lesions (MSML): (i) 0% remaining of MSML (disappearance of MSML) (grade 1), (ii) roughly 10% remaining (grade 2), (iii) roughly 30% remaining (grade 3), (iv) roughly 50% remaining (grade 4), and (v) 100% remaining (no improvement in MSML) (grade 5) (Figure 1). There is also a report that recommends tooth extraction for the treatment of the causative tooth of OMS (5).

In the present study, the tooth was extracted and then maxillary sinuses was irrigated with physiological saline for the following three days. Compared to the control group, significant improvement of the lesions was observed in the irrigation group (mean grade=1.35 vs. 3.27) (Table I, Table II, and Table III). The rate of avoidance of surgery for OMS was very high (94.1%), indicating a significant difference from the control group (65.4%). In this case, injection of physiological saline into the maxillary sinus from the extraction fossa may stimulate the excreting of fluid from the nostril on the affected side. It is thus possible that this process may open up the closure of the foramen in the middle nasal passage between the maxillary sinus and the nasal cavity.

Even at the time of tooth extractions, as well as when liquid was not wasted from the nostrils at the time of tooth extraction, it was possible to cause a waste of liquid from the nostrils when irrigation was performed the next day. Patients said that they experienced the improvement of breathability by irrigation. This strengthens the possibility that irrigation cures the OMS. Furthermore, the irrigation level of maxillary sinuses can be elevated by repeated trials. Even in actual clinical practice, the accumulation of waste was found to reduce day by day after irrigation. Even omission of irrigation yields some improvement (65.4%), consistent with previous report (1, 5). However, the present study demonstrated that approximately 6.7% of patients had maxillary sinus oral fistula, suggesting the necessity of sufficient follow-up. In fact, during the follow-up period, there were cases where maxillary sinus oral fistula closure was performed for outpatients.

In this study, small amounts of macrolides were used for most of the subjects, except one subject who was allergic to macrolides and used Kakkontokasenkyushin’i, a herbal medicine. Macrolides are effective for chronic sinusitis (CRS) accompanied by rhinorrhea and hypersecretion of nasal discharges, as well as for neutrophil-related inflammation accompanied by purulent or mucopurent rhinorrhea. According to Japan’s guidelines for macrolide therapy in the treatment of CRS, macrolides are usually given for 1~3 months (7). A 14-membered macrolide antibiotics such as clarithromycin is used in most of the cases as an anti-inflammatory agent, but not as an antimicrobial agent. Macrolide suppresses mucus secretion in the respiratory tract, improves the inflammation of the respiratory tract by suppressing the production of inflammatory cytokines, bacterial extracorporeal toxins and enzymes, and the formation of biofilm, and increasing the ciliary motility of the respiratory tract (8-10).

It has been reported that ESS should be performed first or at the same time with tooth extraction (5, 11-17). In the present study, tooth extraction was considered first. It is thought that there are few cases of ESS that are really needed. Therefore, two treatment methods of odontogenic maxillary sinusitis can be used, depending on the presence or absence of extraction of the causative tooth. The first method is to save the tooth by the root canal treatment of the tooth, without extraction. In the chronic phase, a small amount of macrolide is administered for three months and examined using CT. If it showed no favorable effect, ESS is performed. The second method is used, when the causative tooth was extracted. When it is possible to clean the maxillary sinus, it is washed with physiological saline from the extraction fossa into the maxillary sinus, and the waste fluid was suctioned out through the nostril on the affected side. This process was repeated for three days, and a small amount of macrolide is administered for 3-4 months. When this method has no effect, ESS is performed. The present study suggested that the treatment of odontogenic maxillary sinusitis should be selected using the above-mentioned methods.

In conclusion, irrigation significantly augmented the therapeutic efficacy of tooth extraction for maxillary sinus mucosal lesions. The combination of tooth extraction and irrigation may contribute to avoid or reduce the frequency of the surgery for the maxillary sinuses.