Does Mandibular Distraction Osteogenesis for Robin Sequence Create Altered Craniofacial Morphology and Disrupt Tooth Development?

BACKGROUND: Robin Sequence (RS) infant patients may require mandibular distraction osteogenesis (MDO) to improve airway. The distracted mandible may grow vertically and the developing dentition may be disrupted. PURPOSE: The study purpose was to measure the association of MDO on craniofacial morphology and tooth development in RS subjects. STUDY DESIGN, SETTING, SAMPLE: This was a retrospective cohort study of RS infants treated with or without MDO. Inclusion criteria were RS diagnosis, complete imaging, and treatment at our pediatric regional hospital. Exclusion criteria were treatment elsewhere and insufficient imaging. EXPOSURE VARIABLE: Exposure was airway management; subjects were grouped by use of MDO or not. Subjects were compared to age-matched normal infants presurgically and to age-matched normal controls at follow-up. MAIN OUTCOME VARIABLES: Main outcome variables were craniofacial morphology measured using cephalometric gonial angle and ramus height to mandibular body length ratio presurgically (T1), postsurgically (T2), and at the mixed dentition (T3). Disrupted tooth development was assessed by absence/abnormality of teeth on radiographs at T3. COVARIATES: Covariates were age, sex, body mass index, comorbidities, and cephalometric measurements. ANALYSES: Appropriate univariate, bivariate, and regression models were computed, and significance level was set at P < .05. RESULTS: The sample contained 14 RS-MDO subjects with median age of 1.1 months and 10 (71.4%) were female. Presurgery, RS-MDO subjects had significantly more obtuse gonial angles (145° vs 137°, P = .04) and shorter mandibular bodies (32 vs 41 mm, P < .01) than the 37 unaffected controls. Increased ramus height (P < .01) and mandibular body length (P < .01) and forward rotation of the mandible were seen in 12 subjects with post-MDO imaging compared to their presurgical condition. At mixed dentition, 12 post-MDO subjects had more obtuse gonial angles (P < .01) and steeper mandibular planes (P < .01) than 19 non-MDO RS subjects. Both RS groups had different cephalometric values and more vertical measures than matched cephalometric norms. Thirty-one percent of 12 RS-MDO subjects had ≥1 teeth with abnormal development compared to none of 19 RS subjects without MDO (P = .02). CONCLUSION AND RELEVANCE: MDO increased mandibular size in infants but can disrupt the developing dentition. Postdistraction growth may result in more vertical mandibular morphology with large gonial angles.

The National Dental Practice-Based Research Network Adult Anterior Open Bite Study: Patient satisfaction with treatment.

INTRODUCTION: This article evaluates and reports on the satisfaction of adult patients across the United States who received orthodontic treatment for anterior open bite malocclusion. The factors that influence satisfaction are also described. METHODS: Practitioners were recruited from the National Dental Practice-Based Research Network. On joining the Network, practitioner demographics and information on their practices were acquired. Practitioners enrolled their adult patients in active treatment for anterior open bite. Patient demographics, patient dentofacial characteristics, and details regarding previous and current treatment were collected through questionnaires at enrollment (T1). Pretreatment lateral cephalograms and intraoral frontal photographs were submitted. Treatment performed, and details related to treatment outcome were recorded through questionnaires at the end of active treatment (T2). Posttreatment lateral cephalograms and intraoral frontal photographs were submitted. Patient satisfaction at T2 was assessed using a 5-point Likert-type scale and open-ended responses. Predictive univariate models were developed to evaluate the factors that affect patient satisfaction. Open-ended responses were reviewed for general trends. RESULTS: T2 data were received for 260 patients, and 248 of these patients completed and returned the patient satisfaction questionnaires. High levels of satisfaction were found in this sample of adult patients receiving treatment for anterior open bite malocclusion. Specifically, 96% of the sample reported being very or somewhat satisfied. Only 10 patients (4%) were not satisfied with the treatment provided or an element of the final result. Successful open bite closure, treatment modality, and certain patient characteristics may affect patient satisfaction. However, there was insufficient power to demonstrate statistical significance because of the very low number of dissatisfied patients. Open-ended responses directly associated with patient satisfaction were received from 23 patients (9%). They relayed positive, neutral, and negative feelings about the treatment received and final results. Additional responses regarding the orthodontic treatment in general, but not specifically linked to patient satisfaction, were received from 119 patients (48%). These comments depict an overwhelmingly positive experience. CONCLUSIONS: Adult patients who received orthodontic treatment for anterior open bite malocclusion were generally satisfied with the treatment provided, as well as the final esthetic and functional results.

The National Dental Practice-Based Research Network Adult Anterior Open Bite Study: Treatment success.

INTRODUCTION: Anterior open bite (AOB) continues to be a challenging malocclusion for orthodontists to treat and retain long-term. There is no consensus on which treatment modality is most successful. This study reports on the overall success rate of AOB orthodontic treatment in the adult population across the United States, as well as 4 major treatment modalities and other factors that may influence treatment success. METHODS: Practitioners and their adult patients with AOB were recruited through the National Dental Practice-Based Research Network. Patient dentofacial and demographic characteristics, practitioner demographic and practice characteristics, and factors relating to orthodontic treatment were reported. Treatment success was determined from posttreatment (T2) lateral cephalometric films and intraoral frontal photographs. Treatment was categorized into 4 main groups: aligners, fixed appliances, temporary anchorage devices (TADs), and orthognathic surgery. Extractions were also evaluated. Bivariate and multivariable models were used to investigate the association between treatment success and treatment modality, pretreatment (T1) dentofacial characteristics, patient and practitioner demographics, and practice characteristics, adjusting for clustering of patients within practice. RESULTS: A total of 254 patients, enrolled by 84 practitioners, contributed to T2 data for this study. There were 29 patients in the aligner group, 152 in fixed appliances, 20 in TADs, and 53 in surgery. A total of 49 patients underwent extractions of teeth other than third molars. Ninety-three percent finished treatment with a positive overbite on the T2 lateral cephalogram, and 84% finished with a positive vertical overlap of all incisors. The small number of aligners and TAD patients limited the ability to compare success rates in these groups. Patients treated with orthognathic surgery had a higher rate of success compared with those treated with fixed appliances only. Treatment success was also associated with academic practice setting, T1 mandibular plane angle ≤30°, no to mild T1 crowding, and treatment duration <30 months. CONCLUSIONS: The overall success of orthodontic treatment in adult patients with AOB who participated in this study was very high. Orthognathic surgery was the only treatment modality that exhibited a statistically higher odds of successful outcomes. Some T1 dentofacial characteristics and treatment factors were associated with the successful closure of AOB.

Botulinum neurotoxin type A in the masseter muscle: effects on incisor eruption in rabbits.

INTRODUCTION: Botulinum neurotoxins are responsible for the paralytic food poisoning, botulism. Commercial formulations such as botulinum neurotoxin type A are increasingly used for various conditions, including cosmetic recontouring of the lower face by injection of the large masseter muscles. The paralysis of a major muscle of mastication lowers occlusal force and thus might affect tooth eruption. The purpose of this study was to investigate the effects of unilateral masseter muscle injection of botulinum neurotoxin type A on the rate of eruption of incisors in a rabbit model. We hypothesized that the teeth would overerupt in an underloaded environment. METHODS: Forty rabbits were injected with either botulinum neurotoxin type A or saline solution in 1 masseter muscle. Mastication and muscle force production were monitored, and incisor eruption rate was assessed by caliper measurement of grooved teeth. RESULTS: The injection of saline solution had no effect. The masseter muscle injected with botulinum neurotoxin type A showed a dramatic loss of force 3 weeks after injection despite apparently normal mastication. Incisor eruption rate was significantly decreased for the botulinum neurotoxin type A group, an effect attributed to decreased attrition. CONCLUSIONS: This study has implications for orthodontics. Although findings from ever-growing rabbit incisors cannot be extrapolated to human teeth, it is clear that botulinum neurotoxin type A caused a decrease in bite force that could influence dental eruption.

Effectiveness of MI Paste Plus and PreviDent fluoride varnish for treatment of white spot lesions: a randomized controlled trial.

INTRODUCTION: White spot lesions are a common sequela of orthodontic therapy. In this parallel-group randomized trial, we assessed the effectiveness of 2 agents commonly used to ameliorate white spot lesions compared with a normal home-care regimen. METHODS: Patients aged 12 to 20 years were recruited from the offices of orthodontists and dentists who belonged to the Practice-based Research Collaborative in Evidence-based Dentistry network. The patients had their orthodontic appliances removed within the past 2 months and had at least 1 white spot lesion affecting their maxillary incisors. The subjects were randomized to 1 of 3 arms: (1) an 8-week regimen of MI Paste Plus (GC America, Alsip, Ill), (2) a single application of PreviDent fluoride varnish (Colgate Oral Pharmaceuticals, New York, NY), and (3) usual home care (control). Photographs were taken at enrollment and 8 weeks later. Two panels consisting of 5 dental professionals and 5 laypersons assessed the before-and-after pairs of photographs in a blinded fashion. Objective assessments and self-assessments were also performed. RESULTS: One hundred fifteen subjects completed the study; 34 were assigned to the MI Paste Plus group, 40 to the fluoride varnish group, and 41 to the control group. The mean improvements assessed by the professional panel were 21%, 29%, and 27% in the MI Paste Plus, fluoride varnish, and control groups, respectively.The results from the lay panel were 29%, 31%, and 25%, respectively. Objective improvements in the surface affected were 16%, 25%, and 17%, respectively; self-assessments of improvement were 37% in all 3 groups. No assessments indicated significant differences between subjects in the active arms compared with the control arm. CONCLUSIONS: MI Paste Plus and PreviDent fluoride varnish do not appear to be more effective than normal home care for improving the appearance of white spot lesions over an 8-week period.

Medicaid and privately financed orthodontic patients have similar occlusal and psychosocial outcomes.

OBJECTIVE: This study compares occlusal and psychosocial outcomes from comprehensive orthodontic treatment in Medicaid (MC) and privately financed (private pay, PP) patients. METHODS: Two cohorts received comprehensive orthodontics: MC (n = 66); PP (n = 60). A calibrated, blinded examiner scored dental casts at baseline (pretreatment, T1) and after completing 2 years of treatment (posttreatment, T2) using the Peer Assessment Rating (PAR) and the Index of Complexity, Outcome, and Need (ICON). The prevalence of patients in the validated ICON categories for treatment need, complexity, and improvement were calculated. Questionnaires to assess body image (BI) and expectations/experiences were administered. Occlusal measures at T2 were compared after adjustment for baseline characteristics. Psychosocial measures were compared between and within groups. Occlusal and psychosocial associations were evaluated. RESULTS: MC was 1.3 years younger (P < 0.001) and had worse malocclusions at baseline (PAR 32 versus 25; P < 0.001); (ICON 64 versus 56; P = 0.06). After adjustment for age and initial severity, estimated average differences between groups at T2 (MC-PP) were slight: 1.5 [95 percent confidence interval (CI) -2.9, 5.9] and 2.4 (95 percent CI -4.4, 8.9) for PAR and ICON, respectively. More PP completed treatment under 2 years (85 percent versus 62 percent; P = 0.03). At baseline, both groups needed treatment, but MC malocclusions were more complex (P = 0.05). At T2, both groups were acceptable and there were no differences in ICON improvement categories. Group differences in psychosocial measures and associations between psychosocial and occlusal measures were evident in the "teeth" domain but weak or lacking elsewhere. CONCLUSIONS: Occlusal and psychosocial outcomes from orthodontics in MC and PP were comparable, despite worse MC malocclusions at baseline.

Bisphosphonates as a risk factor for adverse orthodontic outcomes: a retrospective cohort study.

INTRODUCTION: Bisphosphonates are a class of drugs commonly prescribed to treat osteoporosis. They act by decreasing the resorption of bone. Since tooth movement depends on bone remodeling, these drugs can impact orthodontic treatment. The purpose of this study was to evaluate the extent to which bisphosphonate therapy is a risk factor for poor orthodontic outcomes. METHODS: Orthodontists were invited to participate in the study by performing case reviews of women over age 50 who were treated from 2002 through 2008. Women who used bisphosphonates were compared with women who did not have a history of bisphosphonate use. Outcomes assessed included treatment time, osteonecrosis of the jaws, incisor alignment, incomplete space closure, and root parallelism. RESULTS: The records for 20 subjects with bisphosphonate exposure were collected, as well as records for 93 subjects without bisphosphonate exposure. In patients undergoing extractions, treatment times were significantly longer if they had a history of bisphosphonate use. No occurrences of osteonecrosis of the jaws were reported, nor did patients end treatment with incisor alignment discrepancies greater than 1 mm, regardless of bisphosphonate exposure. Among patients with extractions or initial spacing, there were higher odds of incomplete space closure (odds ratio, 13) and poor root parallelism (odds ratio, 26) at the end of treatment for patients using bisphosphonates. CONCLUSIONS: Bisphosphonate use is associated with longer treatment times among extraction patients, increased odds of poor space closure, and increased odds of poor root parallelism.

Long-term stability of anterior open-bite closure with bilateral sagittal split osteotomy.

INTRODUCTION: Maxillary impaction and bimaxillary osteotomies are used to treat anterior open-bite malocclusions but can have adverse soft-tissue effects. Correcting an anterior open bite with a single mandibular procedure avoids these undesirable soft-tissue effects, but the stability of this procedure is unknown. The purpose of this study was to assess the long-term stability of anterior open-bite correction with bilateral sagittal split osteotomy and rigid internal fixation. METHODS: Orthognathic surgical records of 1 oral surgeon were searched for all patients treated for anterior open bite with bilateral sagittal split osteotomy and surgical closing rotation of the mandible with rigid internal fixation. Cephalometric films from initial consultation, presurgery, postsurgery, orthodontic appliance removal, and a mean of 4.5 years after orthodontic appliance removal were collected, traced, and measured. RESULTS: Thirty-one patients fit the inclusion criteria for this study and had an initial mean open bite of -2.6 mm (SD, 1.1 mm). The patients experienced an average mandibular closing rotation of 3.7° (SD, 2.4°) with surgery. By orthodontic appliance removal, the mandible rotated open 1.1°, and incisor overlap was 1.4 mm (SD, 1.0 mm). Approximately 4.5 years after orthodontic appliance removal, the mean incisor overlap was maintained at 1.0 mm (SD, 1.0 mm), yet the mandible rotated open an additional 1.1°. Only 3 patients relapsed to no incisor overlap in the long term, and only 3 patients experienced relapse greater than 1 mm in the long term. CONCLUSIONS: Approximately 90% of the treated patients had a positive incisor overlap 4.5 years after orthodontic appliance removal. Despite a 60% loss of mandibular surgical closing rotation, only 10% of the patients relapsed to no incisor overlap in the long term. Bilateral sagittal split osteotomy and surgical closing rotation of the mandible by using rigid internal fixation should be considered a stable alternative in the treatment of mild-to-moderate anterior open-bite malocclusions.

Stability of treatment for anterior open-bite malocclusion: a meta-analysis.

INTRODUCTION: Anterior open-bite (AOB) treatment is considered challenging because of difficulties in determining and addressing etiologic factors and the potential for relapse in the vertical dimension after treatment. In this review, we compiled evidence on the long-term stability of the major therapeutic interventions for correcting AOB. Our objective was to review and compile evidence for the stability of surgical and nonsurgical therapies for AOB malocclusion. Our data sources were PubMed, EMBASE, Cochrane Library, limited gray literature search, and hand searching. METHODS: A search was performed of the electronic health literature on the stability of AOB after treatment. Hand searching of major orthodontic journals and limited gray literature searching was also performed, and all pertinent abstracts were reviewed for inclusion. Full articles were retrieved for abstracts or titles that met the initial inclusion criteria or lacked sufficient detail for immediate exclusion. Studies accepted for analysis were reviewed and their relevant data retrieved for pooling. The long-term stability estimates were pooled into nonsurgical and surgical groups, and summary statistics were generated. RESULTS: One hundred five abstracts met the initial search criteria, and 21 articles were included in final analyses. Rejected articles failed to exhibit follow-up times of 12 months or more, did not include measurements of overbite (OB), or did not meet inclusion criteria. All included articles were divided into a surgical group (SX) with a mean age of 23.3 years and a nonsurgical group (NSX) with a mean age of 16.4 years. All studies were case series. Random-effects statistical models were used to pool the mean OB measures before and after treatment and also at the long-term follow-up. The pretreatment adjusted means of OB were -2.8 mm for the SX and -2.5 mm for the NSX. AOB closures up to +1.6 mm (SX) and +1.4 mm (NSX) were achieved. Relapse in the SX group during the mean 3.5 years of follow-up reduced the OB to +1.3 mm; the NSX group relapsed to +0.8 mm in the mean 3.2 years of follow-up. Pooled results indicated reasonable stability of both the SX (82%) and NSX (75%) treatments of AOB measured by positive OB at 12 or more months after the treatment interventions. CONCLUSIONS: In the included case series publications, success of both the SX and NSX treatments of AOB appeared to be greater than 75%. Because the SX and the NSX were examined in different studies and applied to different clinical populations, no direct assessment of comparative effectiveness was possible. The pooled results should be viewed with caution because of the lack of within-study control groups and the variability among studies.

Dental effects of interceptive orthodontic treatment in a Medicaid population: interim results from a randomized clinical trial.

INTRODUCTION: There are disparities in access to orthodontic treatment for children from low-income families. Systematic programs of limited-care interceptive and preventive orthodontics have been proposed as a solution. The purpose of this randomized clinical trial was to compare dental outcomes and funding eligibility from a group of Medicaid patients randomized to receive interceptive orthodontics (IO) in the mixed dentition or observation (OBS). METHODS: One hundred seventy Medicaid-eligible children were randomized to receive IO or OBS and followed for 2 years, when complete data were available on 72 and 74 children, respectively. The 2-year changes in the peer assessment rating (PAR) were compared using the Student t test. The proportions of children no longer eligible for Medicaid funding as defined by handicapping labiolingual deviation (HLD) scores less than 25 at the 2-year follow-up were compared with the chi-square test. RESULTS: The IO patients had significantly greater decreases in the PAR scores--50%-compared with the OBS subjects, -6% (P <0.001). Negative and positive overjet and maxillary alignment were the components most affected by IO; they decreased by 11.0, 7.2, and 3.7 PAR points, respectively (P <0.001). Overbite showed little change. At the 2-year follow-up, 80% of the IO patients' malocclusions that qualified initially were no longer deemed medically necessary by the HLD index, compared with 6% in the OBS group (P <0.001). CONCLUSIONS: IO significantly reduces the severity of malocclusions and moves most from the "medically necessary" category to elective but does not produce finished results for most patients. Overjet and alignment were most readily corrected by interceptive treatment. Deep overbites were the least susceptible to IO correction.

Effects of malocclusion and its treatment on the quality of life of adolescents.

INTRODUCTION: The relationship between malocclusion and quality of life (QoL) is complex and not well understood. The objective of this study was to determine whether malocclusion and its treatment influence an adolescent's general and oral health-related QoL. METHODS: An observational, cross-sectional design with a longitudinal component was used. Clinical and self-reported data were collected from 293 participants aged 11 to 14. The children were recruited from orthodontic and pediatric dental clinics at the University of Washington and a community health clinic in Seattle. The participants were classified into precomprehensive orthodontic (n = 93), postinterceptive orthodontic (n = 44), and nonorthodontic comparison (n = 156) groups. Assessments of dental esthetics and occlusion were evaluated with the Index of Complexity, Outcome, and Need. Three QoL questionnaires were completed: Youth Quality of Life to assess general QoL, Children's Oral Health-Related Quality of Life to assess oral health QoL, and Treatment Expectations and Experiences to evaluate participants' expectations for changes in specific aspects of their lives. Nonparametric tests were used for all analyses. RESULTS: In general, overall and oral health QoL were high in this population. The instruments were correlated so that when oral health QoL improved, so did general QoL. No differences were found in these measurements between the university and community health clinics. Nor were there differences between the 3 study groups on general QoL and oral health QoL. There was little effect of malocclusion complexity on any QoL measure. Both preorthodontic and postorthodontic participants expected improvements in their health, oral function, appearance, and social well-being after orthodontic treatment; the postinterceptive sample's posttreatment experiences were consistent with their pretreatment expectations in all domains. CONCLUSIONS: Malocclusion and orthodontic treatment do not appear to affect general or oral health QoL to a measurable degree, despite subjective and objective evidence for improved appearance, oral function, health, and social well-being.

The National Dental Practice-Based Research Network adult anterior open bite study: A description of the practitioners and patients.

OBJECTIVES:: To describe the demographic and practice characteristics of the clinicians enrolled in a large, prospective cohort study examining recommendations and treatment for adult anterior open bite (AOB) and the relationship between these characteristics and practitioners' self-reported treatment preferences. The characteristics of the AOB patients recruited were also described. MATERIALS AND METHODS:: Practitioners were recruited from the National Dental Practice-Based Research Network. Participants in the study consisted of practitioners and their adult AOB patients in active treatment. Upon enrollment, practitioners completed questionnaires enquiring about demographics, treatment preferences for adult AOB patients, and treatment recommendations for each patient. Patients completed questionnaires on demographics and factors related to treatment. RESULTS:: Ninety-one practitioners and 347 patients were recruited. Demographic characteristics of recruited orthodontists were similar to those of American Association of Orthodontists members. The great majority of practitioners reported using fixed appliances and elastics frequently for adult AOB patients. Only a third of practitioners reported using aligners frequently for adult AOB patients, and 10% to 13% frequently recommended temporary anchorage devices (TADs) or orthognathic surgery. Seventy-four percent of the patients were female, and the mean age was 31.4 years. The mean pretreatment overbite was -2.4 mm, and the mean mandibular plane angle was 38.8°. Almost 40% of patients had undergone orthodontic treatment previously. CONCLUSIONS:: This article presents the demographic data for 91 doctors and 347 adult AOB patients, as well as the practitioners' self-reported treatment preferences.