Association Between Increased Concavity of Maxillary Labial Alveolar Bone and Decreased Labial Cortical Bone...

To assess whether an increased concavity of maxillary labial alveolar bone is related to labial thickness of cortical bone in that area and to the presence of extraoral manifestations in the philtrum.

Cone beam computed tomography images along with intra- and extraoral photographic images of 50 Caucasian female patients, age range 18 to 65 years (mean: 37 years), previously evaluated for implant treatment were assessed by three experienced prosthodontists. Patients were divided into two groups (A and B), according to the presence or absence of a horizontal groove at the philtrum area. Mann-Whitney U test (α = 0.05) was performed to reveal any statistical differences regarding the angle of the maxillary labial concavity and the labial thickness of the alveolar cortical bone between the two groups.

The mean angle of the maxillary concavity in group A was 127.76° while in group B it was 137.12°. The mean thickness of the labial cortical wall of the dental, interdental, and edentulous areas of the 8 anterior teeth for group A were: 0.41 mm, 0.61 mm, and 0.46 mm, respectively; and for group B were: 0.52 mm, 0.72 mm, and 0.56 mm, respectively. The Mann-Whitney U test (α = 0.05) revealed a statistically significant difference for both the angle (p = 0.008) but not for the thickness of the bone (p = 0.062).

According to the results of this study an increased maxillary labial concavity was associated with reduced thickness of the labial cortical wall and the presence of a horizontal groove at the philtrum area.