Cephalometric Analysis and Long-Term Outcomes of Surgical Jaw Advancement in Obstructive Sleep Apnea


Purpose: To describe the posterior airway space and soft tissue changes in patients who received orthodontics and single or dual surgical jaw advancement and to evaluate if there is a correlation between increasing amounts of advancement and long-term reduction in obstructive sleep apnea.

Methods: Records were searched from one oral surgeon and one orthodontist for all patients treated by bilateral sagittal split osteotomy (BSSO) or maxillomandibular advancement (MMA) done in combination with orthodontics. Cephalometric films from pre-treatment, pre-surgery, post-surgery, and final removal of appliances were collected and traced.  Pre-surgical and Post-surgical polysomnography results were collected, specifically the apnea-hypopnea indexes (AHI). The patients were recruited to complete a questionnaire and Epworth Sleepiness Scale (ESS) to assess long-term outcomes from treatment. Descriptive statistics were calculated for all cephalometric measurements and the data was analyzed for change from initial to final measurements with significance level set at P < .05. Linear regressions were performed to find estimates for the final OSA outcomes (AHI and ESS) as a function of mandibular advancement.

Results: Forty-three patients, treated from 1995-2010, were identified for the study. Twenty-nine patients had a complete cephalometric film series. The maxilla and mandible were advanced 5.2 mm and 8.3 mm respectively, with a mean 4 mm increase in posterior airway space. The upper and lower lip protrusion increased by 4.8 mm and 7.6 mm but there was no significant change in relation to the nose-chin line. The soft tissue chin increased by 11.3 mm. Thirty-three patients completed the long-term survey at a mean 6.3 years ± 2.6 (range 2-12 years) after removal of appliances. The majority of patients (90%) reported reduction of their OSA symptoms and were pleased with their facial appearance. 79% of patients would recommend the orthodontic and surgical management of OSA to prospective candidates. 22 patients had initial AHI and final ESS values to assess final ESS score as a function of mandibular advancement. The mandibular advancement regression coefficient was -0.03 statistically and clinically insignificant. Twelve patients had initial and final AHI values to assess final AHI value as a function of mandibular advancement. The regression coefficient of mandibular advancement was 0.05, also statistically and clinically insignificant. No correlation could be found due to the lack of variation of mandibular advancement and limited sample size.

Conclusions: Soft tissue profile characteristics, AP airway dimensions, and skeletal maxillomandibular advancement were significantly increased after MMA. Soft tissue parameters were considerably protrusive but still demonstrate facial harmony. There was no evidence of a linear relationship between greater amounts of mandibular advancement and improvement of OSA outcomes. An advancement threshold could not be evaluated due to the limited sample size. Patients well below the recommended 10 mm advancement had successful objective short-term and subjective long-term reduction in OSA symptoms. Overall, patients were satisfied with their OSA management, facial aesthetics, and would recommend the treatment to others.

Characteristics and Fate of Orthodontic Articles Submitted for publication: An exploratory study of the American Journal of Orthodontics and Dentofacial Orthopedics

Nadia Farjo DMD

Purpose: The orthodontic literature lacks any study that investigates the characteristics and fate of manuscripts submitted to a top journal, such as the American Journal of Orthodontics and Dentofacial Orthopedics (AJO-DO). Having such information could be valuable to authors and editors alike in understanding critical aspects of the review process.

Methods: This exploratory study looked at original articles submitted to the AJO-DO in 2008 and gathered the following information: (1) For rejected articles: main reason for rejection, publication elsewhere, and journal of subsequent publication where applicable; (2) For accepted articles: number/type of revisions and time elapsed to publication; (3) For all articles: study topic, study design, area of origin, and presence of statistically significant findings. Descriptive statistics were used to describe the manuscripts in terms of the above characteristics. Interactions between the above characteristics and rejection/acceptance/publication elsewhere were explored and reported using the Chi-squared test for equality of proportions, with Fisher’s exact test used for samples of five and below. Post-hoc pairwise tests were checked against the Bonferroni correction to account for multiple testing.

Results: Of the 440 original articles submitted to the AJO-DO in 2008, 113 (25.9%) were accepted for publication while 323 (74.1%) were rejected. All accepted articles underwent either major or minor revision before acceptance and were published in an average of 20.9 months (sd=4.9) after acceptance. Of the rejected articles, 137 were subsequently published in 58 different journals with an average time to publication of 22.2 months (sd=10.9) after rejection from AJO-DO. Among articles not accepted by AJO-DO, the top three reasons for rejection were: (1) Poor study design/small sample size (59% of rejected papers); (2) Outdated/Unoriginal topic (41.5%); and (3) Inappropriate for AJO-DO audience (27.2%). Manuscripts rejected for poor study design had the least success in subsequent publication, while those rejected as inappropriate for the AJO-DO had the highest rate of publication elsewhere. Neither study topic nor study design were significantly associated with acceptance to AJO-DO or publication elsewhere except among rejected observational studies, where it was found that cross-sectional studies were most likely to be published elsewhere, and case series had the least success (p=0.002). Area of origin was found to be significantly associated with acceptance to AJO-DO, with articles from USA and Canada most likely to be accepted (p<5×109). An inverse relationship was seen for publication of rejected articles in other journals, where countries with the least publishing success with AJO-DO had the highest rate of publication elsewhere. The presence of statistically significant findings was shown to be significantly associated with acceptance to AJO-DO (p=0.013) but not with publication elsewhere (p=0.77).

Conclusions: Rejection by AJO-DO does not preclude publication elsewhere. Geographic origin is a predictor of acceptance to AJO-DO as well as subsequent journals. Authors aiming to maximize their chance of article acceptance should submit to an appropriate journal, use a well-designed and described study with adequate sample sizes, and emphasize the novelty and relevance of their work.

A Retrospective Investigation of the Effects and Efficiency of Self-ligating and Conventional Brackets

Megha Anand 

Introduction: Marketing strategies for self-ligating brackets have focused on less need for extractions and faster treatment. Recent meta-analyses have not found these claims to be well supported, but they point out limitations of the current evidence. These meta-analyses also conclude that additional, well-designed studies are indicated to improve our evidence base. The purpose of this retrospective cohort study is to assess the effectiveness and efficiency of treatment with self-ligating brackets compared to conventional brackets. A secondary purpose is to identify any pretreatment malocclusion characteristics associated with choice of either self-ligating or conventional brackets.

Methods: Patients treated in the private offices of two practitioners who simultaneously used both self-ligating and conventional brackets were selected for this study. The self-ligating subjects were selected first, and for each subject, an age and gender matched subject was chosen from the respective office. The self-ligation subjects were consecutively treated adolescents and young adults (11-25 years-old) who completed comprehensive fixed appliance therapy between January 1, 2011 and April 31, 2012. Patients with craniofacial anomalies, surgical treatment, treatment with arch expansion using expanders, interdisciplinary treatment, and incomplete records were excluded. The outcome measures were changes in the intercanine width, intermolar width, and arch length for both arches, change in mandibular incisor inclination, final PAR score, percent PAR reduction, overall treatment time, total number of visits, number of emergencies, number of broken brackets, and other emergencies such as a wire sliding to one side or the loss of ligation. All measurements were performed on digital models or digital lateral cephalograms in a blinded manner. PAR scores were measured by two calibrated assessors and the average of the two scores were used. Data were analyzed using the independent sample t-test, chi-square or fisher exact test and linear regression analysis.

Results: The final sample comprised 74 patients from Clinician 1, and 34 patients from Clinician 2.  The two clinicians exhibited significant differences in treatment duration, as well as in treatment strategies, such as the use of the SureSmile technique. Therefore, the decision was made not to pool the data from the two offices. For Clinician 1, no significant differences were observed between self-ligating and conventional brackets for the outcomes described above, other than increased arch length in both arches in the self-ligating group.  The self-ligation patients treated by Clinician 2 demonstrated a significant increase in transverse dimension, less percent reduction in PAR score, less treatment time, fewer visits, and more wire sliding emergencies compared to the conventional bracket group.

Conclusions: While some significant findings were observed, the small sample and lack of consistent findings between the two clinicians makes it difficult to draw strong conclusions.

Comparing Nasolabial Measures Using Casts and Facial Scans In Infants with Non-Syndromic Clefts


Objective: To compare nasolabial measurements on nasal casts and facial scans in infants with non-syndromic clefts.

Data: Two types of clinical records obtained prior to and post- presurgical: (1) digital scans of nasal casts (N = 35); (2) 3dMD facial scans (N = 69); 34 of which had repeated facial scans on the same day.

Main Outcome Measures: (1) columellar angle; (2) columella length on the noncleft or right side; (3) columella length on the cleft or left side; (4) nasal alar base width on the noncleft or right side; (5) nasal alar base width on the cleft or left side; (6) inter-endocanthal width; (7) nostril dome curvature on the noncleft or right side; (8) nostril dome curvature on the cleft or left side.

Results: There were no significant differences (p > .05) between nasolabial measurements obtained from nasal casts and 3dMD facial scans. Both records can be measured with high intra-rater reliabilities except the nasal alar base width and columella length on the noncleft or right side (p < .005). However, the discrepancies are not clinically significant. Reliability between two raters based on 10 casts and 11 facial scans is fair.

Conclusions: The measurements obtained from casts and 3D facial scans are consistent, both of which show good intra- reliability and inter-rater reliability. Nasolabial measurements are reproducible across repeated 3D facial scans in infants with cleft.