Limits...
Assessment of maxillary third molars with panoramic radiography and cone-beam computed tomography.

Jung YH, Cho BH - Imaging Sci Dent (2015)

Bottom Line: Almost all of the Level C molars were in contact with the roots of the second molar.Erupted teeth most commonly had three roots, and completely impacted teeth most commonly had one root.The superimposition of one third of the root and the sinus floor was most commonly associated with the sinus floor being located on the buccal side of the root.

View Article: PubMed Central - PubMed

Affiliation: Department of Oral and Maxillofacial Radiology, School of Dentistry, Pusan National University, Yangsan, Korea.

ABSTRACT

Purpose: This study investigated maxillary third molars and their relation to the maxillary sinus using panoramic radiography and cone-beam computed tomography (CBCT).

Materials and methods: A total of 395 maxillary third molars in 234 patients were examined using panoramic radiographs and CBCT images. We examined the eruption level of the maxillary third molars, the available retromolar space, the angulation, the relationship to the second molars, the number of roots, and the relationship between the roots and the sinus.

Results: Females had a higher frequency of maxillary third molars with occlusal planes apical to the cervical line of the second molar (Level C) than males. All third molars with insufficient retromolar space were Level C. The most common angulation was vertical, followed by buccoangular. Almost all of the Level C molars were in contact with the roots of the second molar. Erupted teeth most commonly had three roots, and completely impacted teeth most commonly had one root. The superimposition of one third of the root and the sinus floor was most commonly associated with the sinus floor being located on the buccal side of the root.

Conclusion: Eruption levels were differently distributed according to gender. A statistically significant association was found between the eruption level and the available retromolar space. When panoramic radiographs showed a superimposition of the roots and the sinus floor, expansion of the sinus to the buccal side of the root was generally observed in CBCT images.

No MeSH data available.


Related in: MedlinePlus

Eruption levels of maxillary third molars on panoramic radiographs. A. Level A, the occlusal plane of the third molar is at the same level as the adjacent second molar. B. Level B, the occlusal plane of the third molar is between the occlusal plane and the cervical line of the adjacent tooth; C. Level C, the occlusal plane of the third molar is apical to the cervical line of the adjacent tooth.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4697008&req=5

Figure 1: Eruption levels of maxillary third molars on panoramic radiographs. A. Level A, the occlusal plane of the third molar is at the same level as the adjacent second molar. B. Level B, the occlusal plane of the third molar is between the occlusal plane and the cervical line of the adjacent tooth; C. Level C, the occlusal plane of the third molar is apical to the cervical line of the adjacent tooth.

Mentions: We examined the eruption level of the maxillary third molars, the available retromolar space, their relationship to the adjacent second molar, and their relationship to the maxillary sinus on panoramic radiographs. The eruption level of the maxillary third molars was assessed according to their relationship to the occlusal plane of the adjacent second molar using the Pell and Gregory classification system:19 level A; the occlusal plane of the third molar is at the same level as the adjacent tooth; level B, the occlusal plane of the third molar is between the occlusal plane and the cervical line of the adjacent tooth; and level C, the occlusal plane of the third molar is apical to the cervical line of the adjacent tooth (Fig. 1). The available retromolar space was measured as the distance between the distal surface of the second molar crown and the cortex of the maxillary tuberosity, and the space was categorized as sufficient (space greater than or equal to the mesiodistal length of the third molar), reduced (space greater than half and less than the entire mesiodistal length of the third molar), and insufficient (space less than half the mesiodistal length of the third molar) (Fig. 2). The relationship to the adjacent second molar was classified as no contact, contact with the crown, and contact with the root. The relationship of the maxillary third molar to the sinus on panoramic radiographs was classified into five types: class 1, the sinus floor is above the roots; class 2, the sinus floor touches the root tips; class 3, the sinus floor is superimposed on up to one third of the root; class 4, the sinus floor is superimposed on up to two thirds of the root; and class 5, the sinus floor extends up to the tooth cervix (Fig. 3).


Assessment of maxillary third molars with panoramic radiography and cone-beam computed tomography.

Jung YH, Cho BH - Imaging Sci Dent (2015)

Eruption levels of maxillary third molars on panoramic radiographs. A. Level A, the occlusal plane of the third molar is at the same level as the adjacent second molar. B. Level B, the occlusal plane of the third molar is between the occlusal plane and the cervical line of the adjacent tooth; C. Level C, the occlusal plane of the third molar is apical to the cervical line of the adjacent tooth.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4697008&req=5

Figure 1: Eruption levels of maxillary third molars on panoramic radiographs. A. Level A, the occlusal plane of the third molar is at the same level as the adjacent second molar. B. Level B, the occlusal plane of the third molar is between the occlusal plane and the cervical line of the adjacent tooth; C. Level C, the occlusal plane of the third molar is apical to the cervical line of the adjacent tooth.
Mentions: We examined the eruption level of the maxillary third molars, the available retromolar space, their relationship to the adjacent second molar, and their relationship to the maxillary sinus on panoramic radiographs. The eruption level of the maxillary third molars was assessed according to their relationship to the occlusal plane of the adjacent second molar using the Pell and Gregory classification system:19 level A; the occlusal plane of the third molar is at the same level as the adjacent tooth; level B, the occlusal plane of the third molar is between the occlusal plane and the cervical line of the adjacent tooth; and level C, the occlusal plane of the third molar is apical to the cervical line of the adjacent tooth (Fig. 1). The available retromolar space was measured as the distance between the distal surface of the second molar crown and the cortex of the maxillary tuberosity, and the space was categorized as sufficient (space greater than or equal to the mesiodistal length of the third molar), reduced (space greater than half and less than the entire mesiodistal length of the third molar), and insufficient (space less than half the mesiodistal length of the third molar) (Fig. 2). The relationship to the adjacent second molar was classified as no contact, contact with the crown, and contact with the root. The relationship of the maxillary third molar to the sinus on panoramic radiographs was classified into five types: class 1, the sinus floor is above the roots; class 2, the sinus floor touches the root tips; class 3, the sinus floor is superimposed on up to one third of the root; class 4, the sinus floor is superimposed on up to two thirds of the root; and class 5, the sinus floor extends up to the tooth cervix (Fig. 3).

Bottom Line: Almost all of the Level C molars were in contact with the roots of the second molar.Erupted teeth most commonly had three roots, and completely impacted teeth most commonly had one root.The superimposition of one third of the root and the sinus floor was most commonly associated with the sinus floor being located on the buccal side of the root.

View Article: PubMed Central - PubMed

Affiliation: Department of Oral and Maxillofacial Radiology, School of Dentistry, Pusan National University, Yangsan, Korea.

ABSTRACT

Purpose: This study investigated maxillary third molars and their relation to the maxillary sinus using panoramic radiography and cone-beam computed tomography (CBCT).

Materials and methods: A total of 395 maxillary third molars in 234 patients were examined using panoramic radiographs and CBCT images. We examined the eruption level of the maxillary third molars, the available retromolar space, the angulation, the relationship to the second molars, the number of roots, and the relationship between the roots and the sinus.

Results: Females had a higher frequency of maxillary third molars with occlusal planes apical to the cervical line of the second molar (Level C) than males. All third molars with insufficient retromolar space were Level C. The most common angulation was vertical, followed by buccoangular. Almost all of the Level C molars were in contact with the roots of the second molar. Erupted teeth most commonly had three roots, and completely impacted teeth most commonly had one root. The superimposition of one third of the root and the sinus floor was most commonly associated with the sinus floor being located on the buccal side of the root.

Conclusion: Eruption levels were differently distributed according to gender. A statistically significant association was found between the eruption level and the available retromolar space. When panoramic radiographs showed a superimposition of the roots and the sinus floor, expansion of the sinus to the buccal side of the root was generally observed in CBCT images.

No MeSH data available.


Related in: MedlinePlus