Relationship of Associated Vital Structures
When performing extractions of the maxillary molars, it is essential to be aware of the proximity of the molars’ roots to the floor. of the. maxillary sinus. If only a thin layer .of bone exists between the sinus and the roots of the molar teeth, the potential for perforation of the maxillary sinus during the extraction increases. Thus the surgical treatment plan may be altered to an open surgical technique with division of the maxillary molar roots into individual roots before the extraction proceeds (Fig. 7-6).
The inferior alveolar canal may approximate the roots of the mandibular molars. Although the removal of an erupted tooth rarely impinges on the inferior alveolar canal, if an impacted tooth is to be removed, it is important that the relationship between the molar roots and the canal be assessed. Such an extraction may lead to injury to the canal and cause consequent ‘anesthesia of
the inferior alveolar nerve (Fig. 7-7).
A periapical radiograph taken before the removal of mandibular premolar teeth should include the mental foramen. Should a surgical flap be required to retrieve a premolar root, it is essential that the surgeon know where the mental foramen is to avoid injuring the mental nerve during flap development (see Fig. 7-3; Fig. ?-8).