Richard Kulbersh

Periodontal pathogen levels in adolescents before, during, and after fixed orthodontic appliance therapy

INTRODUCTION This purpose of this study was to document and investigate changes in periodontal pathogen levels before, during, and after orthodontic treatment in adolescents. METHODS DNA gene probe analysis was used to quantify the levels of 8 periodontal pathogens before, during, and after treatment with fixed orthodontic appliances in 190 concurrently treated adolescent orthodontic patients. The 8 pathogens examined were Actinobacillus actinomycetemcomitans (AA), Porphyromonas gingivalis (PG), Prevotella intermedia (PI), Tannerella forsythia (TF), Eikenella corrodens (EC), Fusobacterium nucleatum (FN), Treponema denticola (TD), and Campylobacter rectus (CR). Chi-square tests were used to determine whether the percentages of subjects with high counts significantly changed over time. Logistic regression analyses were also performed to derive the relative risk of higher counts of pathogenic bacteria with fixed appliances at the various time intervals studied. RESULTS For 6 (PI, TF, EC, FN, TD, CR) of the 8 pathogens, the percentages of subjects with high pathogen counts increased significantly after 6 months of fixed appliance treatment, but these returned to pretreatment levels by 12 months of orthodontic treatment. No pathogen level was significantly higher after 12 months of orthodontic treatment, and orthodontic treatment was found to be significantly protective for half of the pathogens (EC, FN, TD, CR) posttreatment. CONCLUSIONS Orthodontic treatment with fixed appliances does not increase the risk of high levels of these periodontal pathogens.

CBCT assessment of alveolar buccal bone level after RME.

OBJECTIVE To evaluate the maxillary alveolar buccal bone levels after expansion with banded and bonded expanders, using cone-beam computed tomography (CBCT). MATERIALS AND METHODS The population sample consisted of 22 patients who required expansion during their comprehensive treatment; 10 patients (five males and five females) with a mean age of 13.5 years (CVMS 3) had bonded hygienic expanders, and 12 (six males and six females) with a mean age of 12.6 years (CVMS 3) had banded hyrax expanders. CBCT was taken both before (T1) and 6 months after last activation (T2). Measurements were made for buccal bone thickness (BT), buccal marginal bone level (MBL), and bone thickness level (BTL) at the right first molar (M(Rt)), left first molar (M(Lft)), right first premolar (PM(Rt)), and left first premolar (PM(Lft)). A mixed-design analysis of variance assessed differences between and within the groups. Post hoc t-tests were completed on significant analysis of variance results to determine where differences occurred. RESULTS Analysis of variance revealed no significant differences between or within the two groups. BT significantly decreased horizontally following rapid maxillary expansion. The amount of bone lost was -0.59 mm M(Rt), -0.72 mm PM(Rt), -0.50 mm M(Lft), and -0.57 mm PM(Lft) (P < .003). CONCLUSIONS There was no significant difference between or within the two groups. Buccal bone loss in the vertical dimension (MBL) only showed significance in the banded group for M(Rt) (0.63 mm) and PM(LFt) (0.37 mm) as evidenced by the paired t-test (P < .05).

Assessment of pretreatment orthodontic patients using the BANA test

Ninety-two subjects were tested before orthodontic mechanotherapy for the presence of three putative periodontopathogens-Porphyromonas gingivalis, Treponema denticola, and Bacteroides forsythus-with the BANA test (PerioScan Oral-B). The sample ranged from 9 to 16 years, with a mean age of 13.1 years, and consisted of 51% girls and 49% boys; 48% African American, 46% white, 4% Asian, and 2% Hispanic. Unlike other BANA studies that examined children and adolescents with a 15-minute incubation time, this research used a 5-minute incubation time to increase the specificity and to reduce the false positives obtained from the PerioScan cards. No statistically significant difference was found between the age, gender, or race of the patients and the levels of the three putative periodontopathogens. A Friedman two-way analysis of variance assessed the BANA levels for three groups of teeth: molars, incisors, and premolars. The central incisors and first molars had a significantly higher percentage of positive BANA readings than the first premolars at p < or = 0.05. The clinical importance of this finding has yet to be determined, however, because the central incisor and first molar are the first permanent teeth to erupt, a possible association between dental emergence time and the rate of infection with various organisms may be postulated. In a pilot study, 10 patients from a statistically comparable pretreatment group were assessed longitudinally at two separate collection times separated by 4 months. The Wilcoxon signed rank test indicated no significant changes in these patients over the 4-month period.

A simple and accurate craniofacial midsagittal plane definition

Introduction In this article, we aimed to establish an ideal definition for the craniofacial midsagittal plane (MSP) by first finding an optimal “plane of best fit” and then deriving a simple approximation for clinical use that is highly accurate. Methods For 60 adolescent patients, 3‐dimensional coordinates of 8 central landmarks and 6 pairs of lateral landmarks were collected. Across all patients, the coplanarity of the central landmarks was compared with that of the midpoints of the lateral landmarks. The MSP of best fit was then found by minimizing the mean square distance of the 8 central landmarks to a plane. Across all patients, each possible 3‐point plane was compared with the MSP of best fit with respect to both orientation and proximity. Results The central landmarks were more coplanar and thus more accurate than the midpoints of the lateral pairs. The plane defined by nasion, basion, and incisive foramen was the closest to the MSP of best fit in both orientation and proximity. Conclusions The nasion‐basion‐incisive foramen plane should be used for skull orientation and 3‐dimensional cephalometric analyses because it approximates the MSP of best fit with high accuracy, avoids the use of horizontal reference planes, avoids influence from upper and midface asymmetry, uses easily identifiable relevant landmarks, and is simple to define. HighlightsCentral landmarks of the skull agree on a midsagittal plane (MSP) better than lateral landmarks.“MSP of best fit” is a highly accurate plane that best fits multiple central craniofacial landmarks.A plane passing through Na, Ba, and IF is an optimal approximation of the “MSP of best fit.”The N‐Ba‐IF MSP definition is recommended for skull orientation and 3D cephalometric analyses.