Abstract
Odontogenic maxillary sinusitis is an odontogenic infection caused by inflammation spreading from the apical area to the maxillary sinus. Deciduous teeth are rarely causative factors, as a succedaneous permanent tooth germ is present between those teeth and the bottom of the maxillary sinus. We report here a case of odontogenic maxillary sinusitis caused by apical periodontitis in the maxillary second deciduous molar. A 6-year-5-month-old girl visited our hospital with buccal tenderness and gingival swelling in the area of the left maxillary deciduous molar. CT findings showed mucosal hypertrophy in the bottom of the left maxillary sinus, with interruption of bone continuity in that area also confirmed. Under a diagnosis of odontogenic maxillary sinusitis on the left side caused by apical periodontitis of the left maxillary second deciduous molar, anti-inflammatory treatment was given, then the causative tooth was extracted and a space maintainer attached. The patient was then followed for 1 year 11 months until eruption of the left maxillary second premolar had occurred. For a better understanding of the factors involved in this case, we compared CT images obtained at the time of the first consultation with those obtained 1 year 2 months later, with reference planes set for analysis as follows. A sagittal reference plane was established on the basis of the anterior nasal spine (ANS), posterior nasal spine (PNS), and center of the incisor foremen. A horizontal reference plane including the ANS and PNS, and perpendicular to the sagittal reference plane was also established. Finally, a frontal reference plane was set perpendicular to those 2 planes and contained the ANS. Furthermore, the ANS was established as the reference point (O). Mucosal changes in the bottom of the maxillary sinus and conditions leading to eruption of the succedaneous permanent tooth germ in the bone were analyzed using these reference planes. Regression of mucosal hypertrophy and improvement in the position of the succedaneous permanent tooth germ were evaluated in a quantitative manner. The reference planes utilized in the present study were found useful for comparing CT images obtained over time.
