Morphometric analysis of the maxillary root apex positions according to crowding severity.

OBJECTIVES: To determine differences in arch forms derived from the root apices locations between individuals with <2 mm maxillary crowding and controls. SETTING AND SAMPLE POPULATION: The Department of Orthodontics, Pusan National University. Cone-beam computed tomography (CBCT) images of 102 patients in the control group and 95 patients in the crowding group. MATERIALS AND METHODS: X, Y and Z coordinates of the tip of the crowns and the apex of the root of the maxillary teeth (except second molars) were determined on the CBCT images. The acquired three-dimensional (3D) coordinates were converted into two-dimensional (2D) coordinates via projection on the palatal plane, and the Procrustes analysis was employed to process the converted 2D coordinates. The mean shape of the arch form derived from the location of the tip of the crowns and the apex of the root was compared between groups using the statistical shape analysis. RESULTS: There was a statistically significant difference (P = .046) between the groups for the mean shape of the root apex arch form, but the difference was small and clinically irrelevant as it is minor compared to the degree of crowding. CONCLUSIONS: Maxillary arch from at the level of the maxillary apices only shows minor differences between crowded and non-crowded dentitions.

Cone-beam computed tomography evaluation of short- and long-term airway change and stability after orthognathic surgery in patients with Class III skeletal deformities: bimaxillary surgery and mandibular setback surgery.

The purpose of this study was to evaluate the volumetric change of the upper airway space in 36 Class III patients who had undergone bimaxillary surgery or isolated mandibular setback, and, further, to analyse the relation between post-surgical stability and airway change using cone-beam computed tomography (CBCT). A three-dimensional (3D) CBCT examination was performed at three stages: T0 (before surgery), T1 (an average of 4.6 months after surgery), and T2 (an average of 1.4 years after surgery). The results showed that the volumes of the oropharyngeal and hypopharyngeal airways decreased significantly 4.6 months post-surgery in the mandibular setback group (p<0.05), and these diminished airways had not recovered 1.4 years post-surgery. In the bimaxillary surgery group, the volume of the oropharyngeal airway also decreased. A Spearman correlation analysis showed that the anteroposterior length of the hypopharyngeal area had a correlation with post-surgical stability in the isolated mandibular surgery group, and that the cross-sectional area of the nasopharynx was correlated with maxillary relapse only in the bimaxillary surgery group (p<0.05).

The assessment of the short- and long-term changes in the condylar position following sagittal split ramus osteotomy (SSRO) with rigid fixation.

The purpose of this study was to compare the short- and long-term changes in condylar position related to the glenoid fossa, and skeletal and occlusal stability after orthognathic surgery. All of the study patients were assessed by cone-beam computed tomography images for condylar rotational changes and anteroposterior position in the pre-surgery, post-surgery and post-retention period. The condylar positions were evaluated on three planes: axial, coronal and sagittal. In the skeletal and occlusal measurements, there was no significant difference between the post-surgery group and the post-retention group. After sagittal split ramus osteotomy (SSRO), the condyle on the axial plane rotated inward (P < 0.05) and maintained during the post-retention period. In the anteroposterior condylar position related to the glenoid fossa, the condyles had changed from the anterior position in the pre-surgery group to a concentric position in the post-surgery group and then returned to the anterior position in the post-retention groups. These results suggested that the changed anteroposterior condylar position in the glenoid fossa after SSRO with rigid fixation had moved from a concentric to anterior position for post-retention period.

Fusobacterium nucleatum impairs serum binding to Porphyromonas gingivalis biofilm.

Mouse immune sera obtained by immunization with Fusobacterium nucleatum and then Porphyromonas gingivalis demonstrated an impaired binding capacity to P. gingivalis-biofilm and lower avidity to P. gingivalis when compared with sera obtained from mice immunized with P. gingivalis alone.

Binding aspects of baicalein to HIV-1 integrase.

Human immunodeficiency virus type 1 (HIV-1) integrase is an essential enzyme in the life cycle of the virus. It is responsible for catalyzing the insertion of the viral genome into the host cell chromosome. This integrase is an attractive target for the design of a HIV antiviral drug, because integrase has no human counterpart. In order to know the interaction mode of HIV-1 integrase with its inhibitor, we investigated the effect of the inhibitor, baicalein, on the conformation of the HIV-1 integrase catalytic domain [IN-(50-212/F185K)] using fluorescence and circular dichroism (CD) spectroscopy. We found that baicalein binds to the hydrophobic region of the HIV-1 integrase catalytic core domain. This binding of baicalein induces the conformational change of the enzyme. We also found that the binding ratio of baicalein to the HIV-1 integrase catalytic domain is 2:1.