1 Lateral wall of nasal fossa (medial wall of maxillary sinus) 2 Middle nasal meatus 3 Infraorbital canal 4 Inferior border of orbit 5 Pterygomaxillary fissure 6 Vertebrae 7 Horizontal chin rest (ipsilateral side) 8 Ghost image of horizontal chin rest (contralateral side) 9 Middle nasal concha 10 Inferior nasal concha 11 Orbit 12 Maxillary sinus 13 Hard palate 14 Palatoglossal air space (between the palate and tongue) 15 Zygomatic process of maxilla 16 Posterolateral border of maxilla 17 Zygomatic arch 18 Middle cranial fossa 19 Mastoid air cells and mastoid process 20 Styloid process and ear lobe 21 Mandibular foramen 22 Mandibular canal 23 Coronoid process

1 Nasal meatus 2 Lateral wall of nasal fossa (medial wall of maxillary sinus) 3 Hard palate. The superior arrow points at the ghost image of contralateral palate; the inferior arrow points at the image of ipsilateral palate 4 Superior surface of tongue. The radiolucency between the tongue and the hard palate is the palatoglossal air space 5 External auditory meatus 6 Hyoid bone 7 Horizontal chin rest (ipsilateral side) 8 Ghost image of horizontal chin rest (contralateral side) Image between unnumbered arrows ghost image of contralateral ramus

1 Anterior nasal spine 2 Bite guide (bite block) 3 Bite guide support holder 4 Ghost (reverse) image of lead marker "R" of contralateral side A Right nasal fossa (cavity) B Nasal septum C Left nasal fossa D Orbit E Maxillary sinus F Hard palate. The superior radiopaque line is the ghost image of contralateral palate whereas the inferior radiopaque line is the image of the ipsilateral palate. G Palatoglossal air space H Coronoid process. Sometimes the pterygoid plates are superimposed on the coronoid process I Soft palate J Glossopharyngeal air space 1 Infraorbital canal 2 Medial wall of maxillary sinus (lateral wall of nasal fossa) 3 Ghost image of contralateral ear-ring 4 External auditory meatus 5 Posterolateral border of maxilla 6 Ear lobe pierced with an ear-ring 7 Vertebrae 8 Hyoid bone 9 Horizontal chin rest (ipsilateral side) 10 Ghost image of horizontal chin rest (contralateral side) 11 Chin rest metal support holder

Unnumbered arrows are pointing at the ghost image of contralateral mandible 1 External auditory meatus 2 Styloid process C Middle cranial fossa N Nasopharynx O Glossopharynx R Ear-ring on right ear lobe L Ear-ring on left ear lobe 1 Ghost image of left ear-ring 2 Ghost image of right ear-ring N Nasopharynx (superior to soft palate) S Soft palate O Glossopharynx (inferior to soft palate) E Epiglottis P Palatoglossal air space. The unnumbered two arrows under "P" point at the surface of the tongue C Ghost image of cervical spine M Middle cranial fossa Z Zygomatic arch A External auditory meatus V Vertebrae