White spot lesion-related perception of aesthetics and treatment satisfaction among orthodontic patients, orthodontists and other dental specialists

OBJECTIVE

To investigate the impact of various degrees of white spot lesions (WSLs) of maxillary anterior teeth on the aesthetic perception and treatment satisfaction among orthodontic patients, orthodontists and other dental specialists and to evaluate the differences among the three groups.

METHODS

A total of 45 orthodontic patients (OP), 45 orthodontists (OR) and 45 other dental specialists (OS) were recruited. Subjective evaluations of perceived aesthetics and treatment satisfaction were performed towards eight digitally generated photographs of maxillary anterior teeth with incremental degrees of WSLs using a numerical visual analogue scale (VAS) from 0 to 100. Data were collected and analysed with descriptive statistics, repeated one-way analysis of variance and multivariable generalized estimating equations.

RESULTS

A total of 135 valid questionnaires were collected. Regarding aesthetic scores for WSLs, OP gave more positive scores than OR and OS (p < .05) towards excessive white spot formation without colouration and were more tolerant than OR (p < .05) towards excessive white spot formation with slight colouration. The level of treatment satisfaction for slight to severe WSLs without cavitation was higher in OP than OR. Patients with higher education levels had more negative scores for aesthetic perception and treatment satisfaction (p < .05). Patients who brushed teeth more frequently scored lower in treatment satisfaction (p < .05).

CONCLUSIONS

Orthodontists were the most critical when evaluating aesthetics and treatment satisfaction for slight to severe WSLs without cavitation. For orthodontic patients, better oral hygiene habits and higher education levels were associated with more critical attitudes towards WSLs.

A comparison of skeletal and dental changes in patients with a Class II relationship treated with clear aligner mandibular advancement and Herbst appliance followed by comprehensive orthodontic treatment

INTRODUCTION

The objective of this study was to compare the skeletal and dental changes of patients with a Class II relationship treated with clear aligner mandibular advancement (MA) and Herbst appliances followed by comprehensive orthodontic treatment.

METHODS

The participants included 20 patients treated with MA and 20 with the Herbst appliance. Orthodontic records were taken before treatment, after the functional appliance, and completion of phase II treatment. The skeletal and dental changes across the 3-time periods were evaluated using a matched paired t test for each treatment. A 2-sample t test was used to examine the changes across periods between 2 treatment groups (P <0.05).

RESULTS

Significant reduction in overjet, overbite, and change in molar relationship were obtained by both appliances with similar skeletal and dental contributions. This was contributed by a forward movement of the mandible and mandibular molars, backward movement of the maxillary molars, and retraction of the maxillary incisors. After phase II treatment, both appliances could maintain the skeletal and dental changes achieved during the advancement phase. Greater change in overbite (2.4 mm vs 1.4 mm), an eruption of maxillary incisors (0.9 mm vs 0.1 mm), and proclination of mandibular incisors were found with the Herbst group (3.9° vs -2.1°). The average total treatment time was similar with the 2 appliances.

CONCLUSIONS

Both functional appliances were equally effective in reducing the overjet and overbite and achieving a Class I molar relationship with a similar length of treatment time. The Herbst design lacked control of the mandibular incisor proclination, and clear aligners offered better vertical control and management of the mandibular incisor inclination.

THE USE OF DENTAL PATIENT-REPORTED OUTCOMES AMONG COMPARATIVE OBSERVATIONAL STUDIES IN ORTHODONTICS: A METHODOLOGICAL STUDY

OBJECTIVE

To identify and summarize the presence and characteristics of dental patient-reported outcomes (dPROs) and dental patient-reported outcome measures (dPROMs) within comparative observational studies published in 5 leading orthodontic journals.

METHODS

Electronic searching was performed to identify intervention (therapeutic or preventive) related comparative observational studies published in selected journals between 2015 and 2021. Two authors extracted the characteristics of each included study independently and in duplicate and summarized the dPROs and dPROMs used in these studies. All dPROs were classified into 2 general types (oral health-related quality of life [OHRQoL] and others), while dPROMs were divided into 3 categories (single-item questionnaires, generic multiple-item questionnaires, and specific multiple-item questionnaires). In addition, dPROMs were examined, if they evaluated the 4 dimensions of OHRQoL (oral function, orofacial pain, orofacial appearance, and psychosocial impact).

RESULTS

A total of 683 observational studies were eligible and included of which 117 (17.1%) used dPROs and dPROMs. Seven different dPROs (OHRQoL, patients' satisfaction with treatment, preferences, concerns, compliance, duration, and unwanted events) and 33 different dPROMs (including 8 single-item questionnaires, 11 generic multiple-item questionnaires, and 14 specific multiple-item questionnaires) were identified in these studies. OHRQoL was the most commonly used dPRO (92/117, 78.6%), while Oral Health Impact Profile 14 (OHIP-14) was the most frequently used dPROM (20/92, 21.7%). In terms of study design, cross-sectional studies had the highest proportion of dPRO usage (62/148, 41.9%), followed by cohort studies (63/505, 12.5%) and case-control studies (1/30, 3.3%).

CONCLUSIONS

Only one-sixth of comparative observational studies published in leading orthodontic journals could reflect patients' perspectives. Observational studies in orthodontics need to provide more patient-important information through the use of dPROs and dPROMs.

Association between adenotonsillar hypertrophy and dentofacial characteristics of children seeking for orthodontic treatment: A cross-sectional study

OBJECTIVE

To compare the dentofacial characteristics of children with and without adenoid and/or tonsillar hypertrophy.

METHODS

A consecutive sample of orthodontic patients aged 6-12 that took pre-treatment lateral cephalograms were included in this study. Those with history of previous orthodontic treatment, adenoidectomy or tonsillectomy, or craniofacial anomalies were excluded. The diagnosis of adenoid and tonsillar hypertrophy was based on Fujioka's and Baroni's methods, according to which the subjects were divided into four groups: the adenoid hypertrophy only (AHO) group; tonsillar hypertrophy only (THO) group; combined adenoid and tonsillar hypertrophy (AH+TH) group; and no adenoid or tonsillar hypertrophy (NH) group. Cephalograms were used for skeletal and dental measurement. Data were analyzed using one-way ANOVA, LSD post-hoc tests and Chi-square test.

RESULTS

A total of 598 patients were included. Compared with the NH group, the THO group had significantly larger SNB angle (P < 0.001), as well as significantly smaller ANB angle (P<0.001) and Wits value (P = 0.001). The U1-L1 angle of AHO group was significantly smaller than that in the NH group (P = 0.035). The proportion of adenoid hypertrophy in Class II patients was significantly higher than that in Class III patients (P = 0.001). The proportion of tonsillar hypertrophy in Class III patients was significantly higher than that in Class I patients (P < 0.001) and Class II patients (P < 0.001).

CONCLUSION

Over 80 % of children seeking orthodontic treatment had either adenoid or tonsillar hypertrophy. Children with adenoid hypertrophy tend to have skeletal Class II malocclusion, while those with tonsillar hypertrophy tend to have skeletal Class III malocclusion.

Obstructive sleep apnea-related knowledge, attitude, experience, and behaviors among orthodontic professionals: a survey

PURPOSE

To assess obstructive sleep apnea (OSA)-related experience, knowledge, attitude, and behaviors among orthodontic professionals in China and identify factors associated with their knowledge levels, attitude toward referring, and self-confidence in the management of patients with OSA.

METHODS

An online cross-sectional survey was conducted using a 31-item questionnaire developed with a professional online survey tool ( www.wjx.cn ) and distributed via WeChat (Tencent, Shenzhen, China). Data were collected between January 16 and 23, 2022 and analyzed using the chi-square test, Fisher's exact test, and multivariate generalized estimation equations.

RESULTS

A total of 1760 professionals responded to the survey, and responses to 1611 questionnaires were valid. The average score of correct answers to the 15 OSA knowledge questions was 12.1 ± 2.0. Most of the professionals agreed that it was necessary to identify patients who might have OSA in practice. The top three sources for gaining knowledge of OSA according to the survey were classrooms and textbooks (76.3%), medical lectures (75.7%), and academic conferences (73.2%). The level of knowledge was significantly correlated with self-confidence in treatment (P < 0.001) and willingness to refer patients to otolaryngologists or clinicians of related disciplines (P < 0.001).

CONCLUSIONS

Most orthodontic professionals agreed that there was a need to identify patients with OSA and learn further about related problems. Treatment confidence and willingness of professionals to refer patients were related to the level of OSA knowledge. These findings suggest that promotion of OSA-related education may help improve the care of patients with OSA.

Role of the tonsil-oropharynx ratio on lateral cephalograms in assessing tonsillar hypertrophy in children seeking orthodontic treatment

OBJECTIVES

To analyze the diagnostic value of the tonsil-oropharynx (T/O) ratio on lateral cephalograms for evaluating tonsillar hypertrophy (TH).

METHODS

A cross-sectional study was performed on 185 consecutive children (101 males, 84 females; mean age 7.3 ± 1.4 years) seeking orthodontic treatment. The T/O ratios on lateral cephalograms were calculated following Baroni et al.'s method. Tonsil sizes were clinically determined according to the Brodsky grading scale. Spearman correlation coefficients between the T/O ratio and clinical tonsil size were calculated with the total sample and subgroups and then compared between subgroups. Diagnostic value was analyzed using the receiver operating characteristic (ROC) curve, sensitivity, specificity, positive and negative predictive values, and accuracy.

RESULTS

There was a strong correlation between the T/O ratio and clinical tonsil size in children (ρ = 0.73; P < 0.001). A significantly higher correlation coefficient was found in the Class III children. The ROC curve revealed an area under the curve of 0.90 (95% CI, 0.86-0.94; P < 0.001). The optimal cutoff value of the T/O ratio for predicting TH was 0.58, with a sensitivity of 98.7% and specificity of 64.2%. Employing the cutoff value of 0.5, the sensitivity was 100% and the specificity was 45.9%.

CONCLUSIONS

Measurement of the T/O ratio on lateral cephalograms may be helpful to initial screening in children for TH. Practitioners may combine the clinical examination of tonsil size with the cephalometric findings for a more comprehensive evaluation.

Three-dimensional comparison of bone-borne and tooth-bone-borne maxillary expansion in young adults with maxillary skeletal deficiency

OBJECTIVE

To compare the transverse dental and skeletal changes in patients treated with bone-anchored palatal expander (bone-borne, BB) compared to patients treated with tooth and bone-anchored palatal expanders (tooth-bone-borne, TBB) using cone-beam computer tomography (CBCT) and 3D image analysis.

METHODS

The sample comprised 30 patients with transverse maxillary discrepancy treated with two different types of appliances: bone-borne (Group BB) and tooth-bone-borne (Group TBB) expanders. CBCT scans were acquired before (T1) and after completion of maxillary expansion (T2); the interval was 5.4 ± 3.4 and 6.2 ± 2.1 months between the T1 and the T2 scans of Group TBB (tooth-bone-borne) and Group BB (bone-borne), respectively. Transverse, anteroposterior and vertical linear and angular three-dimensional dentoskeletal changes were assessed after cranial base superimposition.

RESULTS

Both groups displayed marked transverse skeletal expansion with a greater ratio of skeletal to dental changes. Greater changes at the nasal cavity, zygoma and orbital levels were found in Group BB. A relatively parallel sutural opening in an anterior-posterior direction was observed in Group TBB; however, the Group BB presented a somewhat triangular (V-shaped) opening of the suture that was wider anteriorly. Small downward-forward displacements were observed in both groups. Asymmetric expansion occurred in approximately 50% of the patients in both groups.

CONCLUSION

Greater skeletal vs dental expansion ratio and expansion of the circummaxillary regions were found in Group BB, the group in which a bone-borne expander was used. Both groups presented skeletal and dental changes, with a similar amount of posterior palate expansion. Asymmetric expansion was observed in both groups.

The dental and craniofacial characteristics among children with obstructive sleep apnoea: a systematic review and meta-analysis

BACKGROUND

Paediatric obstructive sleep apnoea (OSA) is a sleep breathing disorder which may have dramatic effects on childhood behaviour, neurodevelopment, metabolism, and overall health in children. Malocclusion and craniofacial morphology may be related to paediatric OSA, and therefore provide information for clinicians to recognize, evaluate and treat patients with this sleeping disorder.

OBJECTIVE

The aim of this systematic review was to summarize evidence regarding the association between paediatric OSA and children's dental and craniofacial characteristics.

SEARCH METHODS

PubMed, Embase, and Cochrane Central Register of Controlled Trials were searched from inception to 1 June 2022.

SELECTION CRITERIA

Cross-sectional studies, comparing dental or craniofacial characteristics using clinical dental examinations or radiographic findings between OSA children (less than 18 year, diagnosed with overnight polysomnography) and healthy children, were included.

DATA COLLECTION AND ANALYSIS

The Joanna Briggs Institute Critical Appraisal Checklist for Analytical Cross-Sectional Studies was used to assess the quality of included studies. RevMan software was used for performing the Meta-analyses.

RESULTS

Sixteen studies were included. Meta-analyses showed that the overjet (MD = 0.86, 95% CI: 0.20 to 1.51; P = 0.01), the saggital skeletal jaw discrepancy (ANB; MD = 1.78, 95% CI: 1.04 to 2.52; P < 0.00001) and mandibular plane angle (FH-MP; MD = 3.65, 95% CI: 2.45 to 4.85; P < 0.00001) were greater in OSA-affected children. In contrast, the upper molar arch width (upper first deciduous molar width; MD = -1.86, 95% CI: -3.52 to -0.20; P = 0.03), (Upper second deciduous molar width; MD = -1.06, 95% CI: -1.88 to -0.24; P = 0.01), SNB (MD = -2.10, 95% CI: -3.11 to -1.09; P < 0.0001), and maxillary length (ANS-PNS; MD = -1.62, 95% CI: -2.66 to -0.58; P = 0.002) were smaller in the OSA group.

CONCLUSIONS

This review shows that OSA-affected children tend to present with mandibular retroposition or retrognathia, increased mandibular plane angle and excess anterior overjet. However, these findings need to be viewed with caution as the corresponding differences may not be significant clinically.

REGISTRATION

PROSPERO (CRD42020162274).

THE USE OF DENTAL PATIENT-REPORTED OUTCOMES AMONG RANDOMIZED CONTROLLED TRIALS IN ORTHODONTICS: A METHODOLOGICAL STUDY

OBJECTIVE

To identify and summarize the use and characteristics of dental patient-reported outcomes (dPROs) and dental patient-reported outcome measures (dPROMs) within randomized controlled trials (RCTs) published in 5 leading orthodontic journals.

METHODS

A manual search was conducted to identify intervention (therapeutic or preventive) related RCTs published in selected journals between 2015 and 2021. Two authors extracted the characteristics of each included trial, as well as all outcomes and outcome measures used in these trials independently and in duplicate. Thereafter, the use of dPROs and dPROMs was identified and summarized. We classified all dPROs into 2 general types (oral health-related quality of life [OHRQoL] and others) and dPROMs into 3 categories (single-item questionnaires, generic multiple-item questionnaires, and specific multiple-item questionnaires). We also identified whether these dPROMs assessed 4 dimensions of OHRQoL (Oral Function, Orofacial Pain, Orofacial Appearance, and Psychosocial Impact).

RESULTS

From 4631 examined articles, a total of 315 RCTs were included, of which 76 (24.1%) used dPROs and dPROMs. Eight different dPROs (OHRQoL, patients' satisfaction with treatment, difficulty, compliance, preference, efficacy, duration, and unwanted events) and 34 different dPROMs (including 13 single-item questionnaires, 7 generic multiple-item questionnaires, and 14 specific multiple-item questionnaires) were identified in these trials. OHRQoL was the most commonly used dPRO (n = 71; 93.4%), followed by patients' satisfaction with treatment (n = 10; 13.2%), patient-reported difficulty (n = 5; 6.6%), and patient-reported compliance (n = 4, 5.3%). The 4 most frequently used dPROMs were pain measured with 10 mm Visual Analogue Scale (n = 20; 24.1%), pain measured with Numerical Rating Scale (n = 11; 13.3%), the Feldmann's Questionnaire (2007) (n = 6; 7.2%), and the Oral Health Impact Profile 14 (n = 5; 6.0%).

CONCLUSION

Only about one-fourth of RCTs published in leading orthodontic journals can reflect patients' perspectives. OHRQoL was the most commonly used dPRO in these trials. Substantial heterogeneity exists among dPROMs used for OHRQoL assessment. Efforts are needed from researchers, reviewers, editors and other stakeholders to promote the wide and standardized use of dPROs in orthodontic research.

Anteroposterior relationship of the maxillary central incisors to the forehead in adult Chinese females

Objectives:

The objectives of the study were to evaluate the anteroposterior (AP) relationship of the maxillary central incisors to the forehead in adult Chinese females.

Material and Methods:

The study sample consisted of 100 lateral smiling photographic images of adult Chinese females who were seeking orthodontic treatment (mean age = 24.0 + 6.5 years old). The study sample was compared to a control sample consisting of 100 images of adult Chinese females with harmonious facial profiles downloaded from the internet. The images were resized and rotated to the upright head position in an image editing software. Reference lines were constructed to evaluate forehead inclinations and AP positions of the maxillary central incisors.

Results:

In the control sample, 80% of the maxillary central incisors were positioned between the facial axis point of the forehead (FFA) and the glabella. About 13% were positioned posterior to the FFA point and 7% anterior to the glabella. In the study sample, 31% of the maxillary central incisors were positioned between the FFA point and glabella, 52% posterior to the FFA point, and 18% anterior to the glabella. There was a strong correlation between the position of the maxillary central incisors and forehead inclination in the control sample (r2 = 0.827). The difference in AP maxillary central incisor position relative to the forehead between the two groups was found to be statistically significant (P = 0.000).

Conclusion:

The forehead may be an important landmark when evaluating the AP position of maxillary incisors in adult Chinese female patients.

Three-dimensional evaluation of skeletal and dental effects of treatment with maxillary skeletal expansion

INTRODUCTION

The objective was to determine the skeletal and dental changes with microimplant assisted rapid palatal expansion (MARPE) appliances in growing (GR) and nongrowing (NG) patients using cone-beam computed tomography and 3-dimensional imaging analysis.

METHODS

The sample consisted of 25 patients with transverse maxillary discrepancy treated with a maxillary skeletal expander, a type of MARPE appliance. Cone-beam computed tomography scans were taken before and after maxillary expansion; the interval was 6.0 ± 4.3 months. The sample was divided into GR and NG groups using cervical vertebral and midpalatal suture maturation. Linear and angular 3-dimensional dentoskeletal changes were assessed after cranial base superimposition. Groups were compared with independent-samples t test (P <0.05).

RESULTS

Both groups displayed marked transverse changes with a similar ratio of skeletal to dental transverse changes and parallel sutural opening from the posterior nasal spine-anterior nasal spine; a similar amount of expansion occurred in the anterior and the posterior regions of the maxilla. The maxilla expanded skeletally without rotational displacements in both groups. The small downward-forward displacements were similar in both groups, except that the GR group had a significantly greater vertical displacement of the canines (GR, 1.7 ±1.0 mm; NG, 0.6 ± 0.8 mm; P = 0.02) and anterior nasal spine (GR, 1.1 ± 0.6 mm; NG, 0.5 ± 0.5 mm; P = 0.004).

CONCLUSIONS

Treatment of patients with MARPE appliance is effective in GR and NG patients. Although greater skeletal and dental changes were observed in GR patients, a similar ratio of skeletal to dental transverse changes was observed in both groups.

Changes in the nasal and pharyngeal airway volume with miniscrew-assisted rapid palatal expansion appliances

Objectives:

The purpose of this study was to assess the volumetric changes in the nasal and pharyngeal airway volume in patients with maxillary transverse deficiency treated with miniscrew-assisted rapid palatal expansion (MARPE) appliances.

Material and Methods:

The pre- and post-treatment cone-beam computed tomography scans of 20 subjects who underwent treatment with the MARPE appliance as part of their orthodontic treatment were included in the study. Pre- and post-expansion airway volume measurements of the nasal cavity, nasopharynx, and oropharynx were measured. Linear measurements of the skeletal structures surrounding the nasal cavity were taken to assess the pattern of airway expansion. Paired t-tests were used to evaluate nasal and pharyngeal airway volume changes with expansion. Pearson correlation test was utilized to assess the relationship between nasal and pharyngeal volume changes.

Results:

A total of 17 out of 20 samples had a successful split of the mid-palatal sutures. A significant increase in nasal airway volume (12.0%) was found post-expansion. In addition, a significant increase in linear measurements of the nasal cavity base width in the frontal plane (7.1%) and both the anterior and posterior widths in the transverse dimension (9.4% and 3.4%, respectively) were found. Significant positive correlations were found between airway volumes and increase in width of the maxillary expansion appliance.

Conclusion:

The effects of maxillary expansion with a MARPE appliance include an increase in nasal cavity volume, but not the nasopharyngeal and the oropharyngeal airway volume. The nasal cavity expands in a triangular pattern in both the frontal and transverse dimensions following orthopedic expansion with the MARPE appliance. Increase in airway volume is a result of the increase in width of the maxillary expansion appliance.

Three-dimensional craniofacial changes with maxillary expansion in young adult patients with different craniofacial morphology

Objectives:

Skeletally mature patients with transverse deficiency are best treated with surgically assisted rapid palatal expansion (RPE) procedure. Recent studies have shown that microimplant-assisted RPE (MARPE) appliances can be effective in achieving skeletal expansion in young adults. This retrospective study aimed to evaluate the skeletal and dental alveolar changes in response to treatment with MARPE appliances in three types of anteroposterior skeletal malocclusions using cone-beam computed tomography (CBCT) scans.

Material and Methods:

Seventy-eight subjects diagnosed with maxillary transverse deficiency and treated with the MARPE appliance (mean age of 22.9 ± 4.2 years) were divided into skeletal Class I, II, and III malocclusions with 26 subjects in each group. Pre- and post-treatment CBCT scans were used for superimposition to examine the skeletal and dentoalveolar changes following maxillary expansion treatment.

Results:

Significant lateral separation of the maxilla was found at the levels of the nasal floor, interzygomatic bones, and the inferior palatine margin of the alveolar process (P < 0.05) in the whole sample. Most of the sagittal and vertical variables change significantly in the whole sample and each studied group separately. Intergroup comparisons revealed no significant differences among the three skeletal classes except for the left frontozygomatic angle, left maxillary inclination angle, and torque in the first and second premolars. In Class III patients, the maxilla moved forward significantly in most of the cases (eight of 26 cases) (0.88°, P < 0.05) and the mandible moved downward and backward improving the anteroposterior skeletal relationship. Significant differences were also found in the vertical measurements (N-Me, MMP, and MP/SN, P < 0.05) in all three types of anteroposterior malocclusions.

Conclusion:

Maxillary expansion with the MARPE appliance in young adult patients induced different skeletal and dentoalveolar changes in the anteroposterior and vertical dimensions in each skeletal malocclusion with no significant difference among the three skeletal classes.

Custom fabrication of cast splint microimplant-assisted rapid palatal expansion appliances for treatment of maxillary deficiency in young adults

Background:

The objective of this article was to illustrate the process in the fabrication of a custom cast splint Microimplant-Assisted Rapid Palatal Expansion (MARPE) appliance for treatment of maxillary deficiency in young adults.

Findings:

The fabrication of a custom-made MARPE appliance allows the casting base to design according to the shape of the patient’s palate close to the palatal mucosa. In this new design, one end consists of a casting body, inserting hole, and teeth retention device (circumferential rings) connected to the other end by a jackscrew. Connection of all parts in the integral casting unit increases the strength of the expansion appliance and avoids distortion, deformation, or damage to the palatal mucosa due to increased resistance from the oromaxillofacial area.

Conclusion:

This custom design can improve the clinical outcome of maxillary expansion, especially in patients with narrow and high-arched palates.

Outcomes used in trials regarding the prevention and treatment of orthodontically induced white spot lesions: A scoping review

INTRODUCTION

The objective was to identify and summarize the outcomes and evaluation methods used in clinical trials regarding the prevention and treatment of orthodontically induced white spot lesions (WSLs).

METHODS

Three electronic databases were searched to identify studies that were (1) clinical trials on prevention and/or treatment of orthodontically induced WSLs, (2) reported in English, and (3) published between January 2010 and October 2019. At least 2 authors assessed the eligibility and extracted the characteristics, outcomes, and evaluation methods from included studies. All disagreements were resolved through discussion.

RESULTS

Among 1328 studies identified, 51 were eligible and included. A total of 48 different outcomes and 11 different evaluation methods were used in these studies. The most frequently used outcomes were WSLs clinical visual examination scores (n = 22, 43.1%), DIAGNOdent values (n = 14; 27.5%), fluorescence loss measured with quantitative light-induced fluorescence (QLF) (n = 10; 19.6%), and lesion area measured with QLF (n = 10; 19.6%). The most frequently used evaluation methods were clinical examination (n = 25; 49.0%), visual inspection by photographs (n = 15; 29.4%), DIAGNOdent (n = 14; 27.5%), and QLF (n = 10; 19.6%). None of the included studies reported data on quality of life.

CONCLUSIONS

Substantial outcome heterogeneity exists among studies regarding the prevention and treatment of orthodontically induced WSLs. Most of the identified outcomes are aimed to assess morphologic changes of WSLs and may not reflect patient perspectives.

REGISTRATION

The Core Outcome Set for trials on the prevention and treatment of enamel White Spot Lesions (COS-WSL) project was registered in the COMET Initiative database (No. 1399).

Protocol for the development of a Core Outcome Set for trials on the prevention and treatment of Orthodontically induced enamel White Spot Lesions (COS-OWSL)

BACKGROUND

Enamel white spot lesions (WSLs), characterized by an opaque, matt, and chalky white appearance of enamel, are a sign of incipient caries. WSLs are common in orthodontic practice and can affect both the oral health and dental aesthetics of patients. Extensive studies have been conducted to evaluate the effectiveness of prevention or treatment for orthodontically induced enamel WSLs. However, substantial heterogeneity has been found in the outcomes used for the prevention and treatment of WSLs in literature, which prevents researchers from comparing and combining the results of different studies to draw more decisive conclusions. Therefore, we aim to develop a Core Outcome Set for trials on the prevention and treatment of Orthodontically induced enamel White Spot Lesions (COS-OWSL).

METHODS

The development of COS-OWSL comprises four phases: (1) a scoping review to identify and summarize all existing outcomes that have been used in trials on the prevention or treatment of orthodontically induced WSLs; (2) qualitative interviews with orthodontic patients without (for prevention) and with WSL-affected teeth (for treatment) and relevant dental professionals to identify additional outcomes relevant to them; (3) Delphi surveys to collect opinions from key stakeholders including patients, dental professionals, and researchers and to reach a preliminary consensus; and (4) a consensus meeting to develop the final COS-OWSL.

DISCUSSION

The COS-OWSL will be developed to facilitate the synthesis of evidence regarding the prevention and treatment of orthodontically induced WSLs and to promote the consistent use of relevant patient-important outcomes among future studies in this field.

TRIAL REGISTRATION

Core Outcome Measures in Effectiveness Trials (COMET) initiative (the COS-WSL project) 1399.

Effects of maxillomandibular advancement surgery on a skeletal Class III patient with obstructive sleep apnea: A case report

This case report describes the successful surgical treatment of a patient diagnosed with obstructive sleep apnea (OSA). A 55-year-old Caucasian male patient with a body mass index (BMI) of 25.6 kg/m2 sought treatment with a chief concern of excessive daytime sleepiness and fatigue. An initial polysomnography report showed moderate OSA with an apnea-hypopnea index (AHI) of 21.2 events/h, and Epworth Sleepiness Score (ESS) of 12/24. The patient was initially prescribed with CPAP treatment but was unable to tolerate treatment after a few months. Clinical and radiographic examination revealed a concave facial profile with maxillary retrognathism. Intraoral examination revealed generalized gingival recession, missing upper lateral incisors and lower first premolars, anterior crossbite, and maxillary transverse deficiency with bilateral posterior crossbite. The lateral cephalogram showed a narrow posterior airway space at the level of the base of the tongue. The patient was treated with maxillomandibular advancement (MMA) surgery to improve airway obstruction. Results showed balanced facial esthetic and stable occlusion with a complete resolution of the patient’s OSA and a post-operative improvement of AHI from 21.2 to 0.7 events/h and ESS from 12/24 to 3/24. The lowest oxyhemoglobin saturation during sleep was improved to 97%, and the BMI decreased from 25.6 to 25.2 kg/m2. These results suggest that MMA surgical procedure can be used as a definitive treatment for patients with maxillomandibular deficiency and OSA.

Comparison of skeletal and dentoalveolar changes between pure bone-borne and hybrid tooth-borne and bone-borne maxillary rapid palatal expanders using cone-beam computed tomography

Objectives:

The objectives of the study were to compare the skeletal, dentoalveolar, and periodontal changes between two types of microimplant-assisted rapid maxillary expansion appliances: The bone-anchored maxillary expanders (BAME) and the tooth-bone-anchored maxillary skeletal expander (MSE).

Materials and Methods:

Thirty-four patients with a transverse maxillary deficiency were divided into two groups; the first group (16 patients, average age 14.9 years) was treated with the MSE appliance, and the second group (18 patients, average age 13.8 years) was treated with the BAME appliance. Cone-beam computed tomography scans were taken at pre-treatment (T1) and immediately post-expansion (T2) to measure the changes in midpalatal suture opening, total expansion (TE), alveolar bone bending, dental tipping (DT), and buccal bone thickness. Data were analyzed using paired t-test and two-sample t-test.

Results:

Midpalatal suture separation was found in 100% of the patients in both groups. The TE at the first molar was 5.9 mm in the MSE group and 4.7 mm in the BAME group. The skeletal contributions were 56% and 83% of TE for the MSE and BAME groups, respectively. Significantly less dental buccal tipping and buccal bone loss were found with the BAME group. The midpalatal suture in both groups exhibited a parallel opening pattern in the axial plane.

Conclusion:

The use of BAME appliance resulted in greater skeletal effects, less dental tipping, and less buccal bone reduction compared to MSE appliance (immediately after maxillary expansion).

Early timely orthodontic treatment: Treatment of unerupted maxillary laterals

There is no universal agreement as to which type of orthodontic or orthopedic treatment deserves early intervention. In addition, there is a need for more information as to which treatments are the most effective and less costly if they are initiated timely in the mixed dentition. Early timely treatment may benefit young patients with a maxillary transverse deficiency with or without a posterior crossbite that requires maxillary expansion. It may also be indicated in children with anteroposterior jaw discrepancy that requires chin cup or maxillary protraction. In this paper, the authors will focus on early maxillary expansion to facilitate the eruption of maxillary laterals. In specific, the authors will present a contemporary protocol using a bonded maxillary expander as anchorage for treatment of unerupted maxillary laterals. The use of this protocol was illustrated with two case reports to enable clinicians to routinely achieve a beautiful smile on a young patient by timely alignment of the maxillary incisors.

Stress influence on orthodontic system components under simulated treatment loadings

BACKGROUND AND OBJECTIVE

Mini-implants have been developed and effectively used by clinicians as anchorage for orthodontic tooth movement. The objective of this study was to elucidate the stress response of orthodontic forces on the periodontal system, bone tissues, mini-implant and the bracket-enamel interface.

METHODS

Computer tomography images of a commercially available mini-implant, an orthodontic bracket bonded to a central incisor, and jawbone section models were used to reconstruct three dimensional computer models. These models were exported and meshed in an ABAQUS^Ⓡ finite-element package. Material properties, multi-segment interactions, boundary and loading conditions were then applied to each component. Finite-element analyses were conducted to elucidate the effect of orthodontic force on the equivalent von Mises stress response within the simulated orthodontic system.

RESULTS

The highest stress values in the orthodontic system were predicted at the mini-implant neck, at the interface of the cortical bone, and gradually decreased in the internal apical direction of the miniscrew. On the alveolar bone, the maximum stress values were located in the alveolar cortical bone near the cervical areas of the mini-implant, which is in line with clinical findings of area where bone loss was found post orthodontic tooth treatment. Another peak of von Mises stress response was found in the enamel bracket junction with a maximum up to 186.05 MPa. To ensure good bonding between the enamel and bracket, it is vital to select carefully the type and amount of bonding materials used in the bracket-enamel interface to assure an appropriate load distribution between the teeth and alveolar bone. The results also revealed the significance of the periodontal ligaments, acting as an intermediate cushion element, in the load transfer mechanism.

CONCLUSIONS

This study is sought to identify the stress response in a simulated orthodontic system to minimize the failure rate of mini-implants and bracket loss during orthodontic treatment.

Early class III treatment decision-making

Clinicians make decisions for their patients everyday. Ryan Hamilton, in his course guidebook, How You Decide: The Science of Human Decision Making, summarized the current research on the 4 R's of decision-making that matter: reference points, reasons, resources, and replacement. The authors will apply this principle in the decision- making necessary for the growing Class III patients. First, the decision on whether to treat or not to treat Class III patients in the mixed dentition rely on a thorough diagnosis and objectives for early treatment. For example, elimination of a functional shift of the mandible may be a good reason to institute early treatment. Second, the decision on when to start Phase II treatment relies on the follow-up observation after Phase I treatment. The authors suggested the use of a “checklist” to decide whether patient will be benefited from surgical intervention or nonsurgical orthodontic treatment. If the checklist review has several negative checkpoints, it will help the clinicians to decide on an aggressive stage of 4–8 months therapeutic re-diagnosis to confirm the surgical or nonsurgical decision.

Skeletal, Dentoalveolar, and Periodontal Changes of Skeletally Matured Patients with Maxillary Deficiency Treated with Microimplant-assisted Rapid Palatal Expansion Appliances: A Pilot Study

Introduction

Microimplant-assisted rapid palatal expansion (MARPE) has recently been offered to adult patients for correcting maxillary transverse deficiency. However, there is limited information in the literature on the success of this appliance and its skeletal and dental effects on skeletally matured patients. The purpose of this study was to investigate the immediate skeletal, dentoalveolar, and periodontal response to MARPE appliance using cone-beam computed tomography in a skeletally matured patient as assessed by the cervical vertebral maturation method.

Materials and Methods

Eight consecutively treated patients (2 females, 6 males; mean age of 21.9 ± 1.5 years) treated with a maxillary skeletal expander were included in the study. Measurements were taken before and after expansion to determine the amount of midpalatal suture opening, upper facial bony expansion, alveolar bone bending, dental tipping, and buccal bone thickness (BBT). Data were analyzed using a one-way ANOVA and matched-pair t-test (α = 0.05).

Results

Midpalatal suture separation was found in 100% of the patients with no dislodged microimplants. Total maxillary expansion was attributed to 41% skeletal, 12% alveolar bone bending, and 48% dental tipping. Pattern of midpalatal suture opening was found to be parallel in both the coronal and axial planes. On average, the absolute dental tipping ranged from 4.17° to 4.96° and the BBT was reduced by an average of 39% measured at the premolars and molars.

Conclusions

The MARPE appliance can be a clinically acceptable, nonsurgical treatment option for correcting mild to moderate maxillary transverse discrepancies for skeletally matured adult patients with a healthy periodontium.

Impact of pediatric obstructive sleep apnea on the development of Class II hyperdivergent patients receiving orthodontic treatment: A pilot study

OBJECTIVES

To conduct a pilot study to determine if the presence of obstructive sleep apnea (OSA) influences the orthodontic treatment outcome of Class II hyperdivergent patients receiving comprehensive orthodontic treatment.

MATERIALS AND METHODS

Patients between the ages of 12 and 14 who received orthodontic treatment at the Hospital of Stomatology, Wuhan University, China, were included in this study. Patients were divided into two groups: the OSA group and the control group, based on the outcome of pretreatment polysomnography findings and lateral cephalometric radiograph examination. Patients in the control group were matched with the OSA group for age, sex, ethnicity, weight, and height. Cephalometric measurements were used to record the skeletal and dental changes from before to after treatment. Data were analyzed using the t-test.

RESULTS

Twenty three OSA patients and 23 control patients were included. After comprehensive orthodontic treatment, the mandibular plane angle (SN-GoMe), articular angle (SArGo), sum of Jarabak angles (SUM) and the lower gonial angle (NGoMe) were found to increase significantly in the OSA group but remained unchanged or decreased slightly in the control group ( P < .05). In the non-OSA group, the growth pattern became more horizontal. In contrast, in the OSA group the growth pattern became more vertical. Otherwise, similar treatment results were obtained for both groups in terms of sagittal change and occlusion.

CONCLUSIONS

The presence of OSA in pediatric patients has a deleterious effect on the development of hyperdivergent malocclusions. Early diagnosis and management of pediatric OSA can affect the orthodontic treatment outcome of these patients.

Cephalometric study of Class II Division 1 patients treated with an extended-duration, reinforced, banded Herbst appliance followed by fixed appliances

INTRODUCTION

The Herbst appliance has been used in the treatment of Class II malocclusions with deficient mandibles. Various protocols, including different durations of the orthopedic treatment phase and stepwise advancement of the mandible, have been advocated for increasing the orthopedic effects. The objective of this study was to investigate the skeletal and dental changes in patients treated with a reinforced banded Herbst appliance for an extended duration and fixed appliance therapy.

METHODS

The study group consisted of 30 patients (16 boys, 14 girls; mean age, 12.3 ± 2.5 years) with Class II Division 1 malocclusions who were successfully treated with the new Herbst protocol followed by fixed appliances. Lateral cephalometric radiographs were taken before treatment, at the completion of Herbst treatment, and after removal of fixed appliances. The average treatment times were 1.5 ± 0.7 years for the Herbst treatment and 1.8 ± 0.5 years for the fixed appliances. A control Class II sample from the Bolton-Brush study was used to subtract growth from treatment changes to determine the appliance effect. Data were analyzed using analysis of variance and the Tukey-Kramer test.

RESULTS

After the Herbst treatment, the incisal relationships of all subjects had been overcorrected to end-to-end relationships. Overjet was reduced by 7.2 mm after subtracting changes from growth. The skeletal contribution was 2.5 mm (35%), and the dental contribution was 4.7 mm (65%). The molar relationship was overcorrected to a more Class I relationship by 7.5 mm. The Wits appraisal was improved by 4.2 mm. Vertically, overbite was decreased by 3.3 mm. The maxillary and mandibular molars were extruded by 1 mm. The occlusal plane rotated clockwise by 5° with little change in the mandibular plane angle. After the treatment with fixed appliances, the overjet correction was maintained at 7.6 mm. The skeletal contribution was 2.9 mm (38%), and the dental contribution was 4.7 mm (62%). The molar relationship was corrected to a Class I relationship by 5.9 mm. The Wits appraisal was improved by 3.2 mm. Vertically, overbite was decreased by 4.2 mm. The maxillary and mandibular molars were extruded by 0.3 and 0.8 mm, respectively. The occlusal plane rotated clockwise by 1.2° with little change in the mandibular plane angle.

CONCLUSIONS

Doubling the usual orthopedic treatment time with the reinforced Herbst appliance followed by fixed appliance therapy was effective in correcting Class II Division 1 malocclusions with excess overjet and overbite. In this sample of successfully treated patients, most changes after Herbst and fixed appliance therapy were dentoalveolar (62%). However, the skeletal changes attained in the orthopedic phase of treatment were maintained after fixed appliance therapy.

Comparison of two maxillary protraction protocols: tooth-borne versus bone-anchored protraction facemask treatment

Background

Protraction facemask has been advocated for treatment of class III malocclusion with maxillary deficiency. Studies using tooth-borne rapid palatal expansion (RPE) appliance as anchorage have experienced side effects such as forward movement of the maxillary molars, excessive proclination of the maxillary incisors, and an increase in lower face height. A new Hybrid Hyrax bone-anchored RPE appliance claimed to minimize the side effects of maxillary expansion and protraction. A retrospective study was conducted to compare the skeletal and dentoalveolar changes in patients treated with these two protocols.

Methods

Twenty class III patients (8 males, 12 females, mean age 9.8 ± 1.6 years) who were treated consecutively with the tooth-borne maxillary RPE and protraction device were compared with 20 class III patients (8 males, 12 females, mean age 9.6 ± 1.2 years) who were treated consecutively with the bone-anchored maxillary RPE and protraction appliances. Lateral cephalograms were taken at the start of treatment and at the end of maxillary protraction. A control group of class III patients with no treatment was included to subtract changes due to growth to obtain the true appliance effect. A custom cephalometric analysis based on measurements described by Bjork and Pancherz, McNamara, Tweed, and Steiner analyses was used to determine skeletal and dental changes. Data were analyzed using a one-way analysis of variance.

Results

Significant differences between the two groups were found in 8 out of 29 cephalometric variables (p < .05). Subjects in the tooth-borne facemask group had more proclination of maxillary incisors (OLp-Is, Is-SNL), increase in overjet correction, and correction in molar relationship. Subjects in the bone-anchored facemask group had less downward movement of the “A” point, less opening of the mandibular plane (SNL-ML and FH-ML), and more vertical eruption of the maxillary incisors.

Conclusions

The Hybrid Hyrax bone-anchored RPE appliance minimized the side effect encounter by tooth-borne RPE appliance for maxillary expansion and protraction and may serve as an alternative treatment appliance for correcting class III patients with a hyperdivergent growth pattern.

Treatment and retention of relapsed anterior open-bite with low tongue posture and tongue-tie: A 10-year follow-up

The purpose of the current report is to present 6-year long-term stability and 10-year follow-up data for an adult patient who was treated with a tongue elevator for relapsed anterior open-bite. The 19-year-old male patient presented with the chief complaint of difficulty in chewing his food. Collectively, clinical and radiographic examinations revealed an anterior open-bite, low tongue posture, and tongue-tie. The patient opted for orthodontic treatment alone, without any surgical procedure. A lingual frenectomy was recommended to avoid the risk of relapse, but the patient declined because he was not experiencing tongue discomfort. Initial treatment of the anterior open-bite with molar intrusion and tongue exercises was successful, but relapse occurred during the retention period. A tongue elevator was used for retreatment, because the approach was minimally invasive and suited the patient's requirements regarding discomfort, cost, and time. The appliance changed the tongue posture and generated an altered tongue force, which ultimately resulted in intrusive dentoalveolar effects, and a subsequent counterclockwise rotation of the mandible. The results showed long-term stability and were maintained for six years through continual use of the tongue elevator. The results of this case indicated that a tongue elevator could be used not only as an alternative treatment for open-bite, but also as an active retainer.

Evaluation of masseter muscle morphology in different types of malocclusions using cone beam computed tomography

OBJECTIVES

To evaluate the length and orientation of masseter in different types of malocclusions using Cone Beam Computed Tomography (CBCT).

METHODS

Samples of 180 patients seeking orthodontic treatment at the University of Nevada, Las Vegas School of Dentistry, were included in the study. Pre-treatment multi-slice CBCT scans of these patients were divided into three anteroposterior groups: Class I subjects with ANB angle 0° to 5°; Class II subjects with ANB angle >5°; and Class III subjects with ANB angle <0°. CBCT scans were also divided into three vertical groups: normodivergent subjects with mandibular plane angle 22° to 30°; hyperdivergent subjects with mandibular plane angle >30°, hypodivergent subjects with mandibular plane angle <22°. The masseter was identified and landmarks were placed on the anterior border, at the origin and insertion of the muscle in 3-D mode of the Dolphin Imaging 10.5 Premium software. The Frankfort Horizontal Plane was used as a reference plane and an angular measurement was obtained by intersection of a line produced by the masseter landmarks to calculate the orientation of the muscles. The length of the masseter was measured and data were analyzed using ANOVA and matched pairs test.

RESULTS

ANOVA found significant differences in muscle length among the three vertical groups for both the left and right muscles. Paired t test showed significantly shorter muscle length for the hypodivergent group (43.3 ± 4.0 mm) compared to the normodivergent group (45.6 ± 4.5 mm, P < 0.05) and shorter muscle length for the hyperdivergent group (42.3 ± 4.7 mm) compared to the hypodivergent group, P < 0.05. No significant differences were found in muscle length among the three anteroposterior groups. However, significant differences in muscle orientation angle were found among the three anteroposterior groups (P < 0.05). Class II subjects were found to have the most acute orientation angle (67.2 ± 6.6°) and Class III had the most obtuse orientation angle (81.6 ± 6.8°).

CONCLUSIONS

These results suggest that certain types of malocclusion may have different masseter lengths and orientations and these differences may have implications for the mechanical advantage in bite force. For example, Class III individuals may have greater bite force than Class II individuals because the muscle fibers are oriented more along the arch of closure.

Prevalence of peg-shaped maxillary permanent lateral incisors: A meta-analysis

INTRODUCTION

The aim of this meta-analysis was to gain more insight into the prevalence of peg-shaped maxillary permanent lateral incisors and their associations with race, population type, sex, and sidedness.

METHODS

Electronic searches and supplementary hand searches initially yielded 3337 records. After applying inclusion and exclusion criteria, 30 articles about 36 studies were included. The overall pooled prevalence estimate was calculated with a random-effects model. An estimated risk ratio was used for sex comparison.

RESULTS

The overall prevalence of peg-shaped maxillary permanent lateral incisors was 1.8%. No publication bias was found. The occurrence rates were higher in Mongoloid (3.1%) than in black (1.5%) and white (1.3%) patients, and in orthodontic patients (2.7%) than in the general population (1.6%) and dental patients (1.9%). Women were 1.35 times more likely than men to have peg-shaped maxillary permanent lateral incisors. The prevalence rates of unilateral (0.8%) and bilateral peg-shaped maxillary permanent lateral incisors were approximately the same. However, among the unilateral lateral incisors, the left side (0.4%) was twice as common as the right side (0.2%). In addition, contralateral lateral incisor hypodontia was seen in 55.5% of the subjects with unilateral lateral incisors.

CONCLUSIONS

The prevalence of peg-shaped maxillary permanent lateral incisors varies by race, population type, and sex. The prevalence rates were higher among Mongoloid people, orthodontic patients, and women. Although the prevalence of unilateral and bilateral lateral incisors was the same, the left side was twice as common as the right side. Subjects with unilateral peg-shaped maxillary permanent lateral incisors might have a 55% chance of having lateral incisor hypodontia on the contralateral side.

Effects of twin block appliance on obstructive sleep apnea in children: a preliminary study

BACKGROUND

Oral appliances are increasingly advocated as a treatment option for obstructive sleep apnea (OSA). However, it is not clear how the different designs influence treatment efficacy in children. The aim of this study was to investigate the effects of twin block (TB) appliance on children with OSA and mandibular retrognathia.

METHODS

A total of 46 children (31 males, 15 females, aged 9.7 ± 1.5 years, BMI: 18.1 ± 1.04 kg/m(2)) diagnosed with mandibular retrognathia and OSA by polysomnography (PSG) and with no obesity or adenotonsillar hypertrophy were recruited for the study. Patients in the treatment group were instructed to wear the twin block oral appliance full time for an average of 10.8 months. The efficacy of treatment was determined by monitoring the PSG and cephalometric changes before and after appliance removal. Data were analyzed using paired t test.

RESULTS

Results showed an improvement in patient's facial profile after treatment with the TB appliance. The average AHI index decreased from 14.08 ± 4.25 to 3.39 ± 1.86 (p < 0.01), and the lowest SaO2 increased from 77.78 ± 3.38 to 93.63 ± 2.66 (p < 0.01). Cephalometric measurements showed a significant increase in the superior posterior airway space, middle airway space, SNB angle and facial convexity which indicate an enhancement in mandibular growth, and reduction in the soft palate length.

CONCLUSIONS

This preliminary study suggests that twin block appliance may improve the patient's facial profile and OSA symptoms in a group of carefully selected children presented with both OSA and mandibular retrognathia symptoms.

Stability of Class II treatment with an edgewise crowned Herbst appliance in the early mixed dentition: Skeletal and dental changes

INTRODUCTION

The objectives of this research were to assess skeletal and dental changes in patients with Class II malocclusion treated with the edgewise crowned Herbst appliance in the early mixed dentition and to measure the stability of treatment after a second phase of fixed appliance therapy.

METHODS

Twenty-two patients (ages, 8.4 ± 1.0 years) with Class II Division 1 malocclusion treated consecutively with the edgewise crowned Herbst appliance in the early mixed dentition were studied. Lateral cephalograms were taken before Herbst treatment, immediately after Herbst treatment, and after a second phase of fixed appliance therapy. The results were compared with a control group of untreated Class II subjects selected from the Bolton-Brush study, matched by age, sex, and craniofacial morphology. A total of 37 sagittal, vertical, and angular cephalometric variables were evaluated. Changes in overjet and molar relationship were calculated. Changes due to growth were subtracted to obtain the net changes due to treatment. The data were analyzed by using analysis of variance (ANOVA) and the t tests.

RESULTS

Overcorrection with the Herbst appliance resulted in an average reduction in overjet of 7.0 mm and a change in molar relationship of 6.6 mm. Several factors contributed to the change in overjet: restraint of the forward movement of the maxilla (0.4 mm), forward movement of the mandible (2.0 mm), backward movement of the maxillary incisors (3.7 mm), and forward movement of the mandibular incisors (0.9 mm). Skeletal changes together with a 3.1-mm backward movement of the maxillary molars and a 1.1-mm forward movement of the mandibular molars contributed to the changes in molar relationship. After the second phase of fixed appliance therapy, the change in overjet was reduced to 2.8 mm. Most of the remaining overjet corrections were contributed by the restraint of maxillary growth (2.8 mm). The mandible moved posteriorly by 1.6 mm, and the mandibular incisors moved forward by 0.2 mm. Change in molar relationship was reduced to 2.2 mm. The maxillary molars moved backward by 0.2 mm, and the mandibular molars moved forward by 0.8 mm.

CONCLUSIONS

Overcorrection of Class II malocclusion with the edgewise crowned Herbst appliance in the early mixed dentition resulted in a significant reduction in overjet and correction of the molar relationship. A portion of the correction was maintained after a second phase of fixed appliance therapy because of the continuous restraint of maxillary growth and the dentoalveolar adaptations.

Tooth whitening effects on bracket bond strength in vivo

OBJECTIVE

To test the hypothesis that there is no difference between the bracket survival rate of brackets bonded to bleached and unbleached teeth.

MATERIALS AND METHODS

Thirty-eight patients who required comprehensive orthodontic treatment were included in the study. A split mouth technique was used with one arch exposed to in-office whitening gel containing 38% hydrogen peroxide for 30 minutes, while the unbleached arch served as the control. Patients were divided into two groups: Brackets bonded within 24 hours after bleaching and brackets bonded 2-3 weeks after bleaching. The bracket survival rate was computed using the log-rank test (Kaplan-Meier Analysis).

RESULTS

A significantly higher rate of bracket failure was found with bleached teeth (16.6%) compared with unbleached teeth (1.8%) after 180 days. Brackets bonded within 24 hours of bleaching resulted in significantly higher clinical failure (14.5%) compared with those bonded after 3 weeks (2.1%). Adhesive Remnant Index scores of failed brackets revealed that the majority of failure in bleached teeth occurred in the enamel/resin interface.

CONCLUSIONS

The hypothesis was rejected. Brackets bonded within 24 hours after bleaching have a significantly higher risk for bond failure. Orthodontic bonding should be delayed for 2-3 weeks if patients have a history of in-office bleaching with 38% hydrogen peroxide.

Survey of treatment provided for young children by West Virginia general dentists

PURPOSE

The purpose of this study was to survey the treatment provided by West Virginia general dentists (GDs) for young children.

METHODS

A survey was mailed to 683 GDs in West Virginia. Respondents were questioned about their referrals to pediatric dentists, the youngest age for which they perform specific procedures, conscious sedation utilization, and whether they treat Medicaid-covered children.

RESULTS

The response rate was 72%. Half of the GDs responded that they frequently referred children younger than 3 years old, and only one third reported performing dental examinations on a child 2 years old or younger. All responding GDs performed the surveyed procedures in 5-year-olds, but fewer respondents performed complex procedures for children < or = 2 years old. More than half of the GDs responded that they frequently had difficulty with referrals to a pediatric dentist due to distance/ transportation or not accepting new Medicaid patients. Medicaid-covered children were not treated by 25% of general dentists.

CONCLUSIONS

Most GDs in West Virginia treat older children, but care is limited for children < or = 2 years old. Further studies are needed to uncover the specifics of these findings to improve the access and care for young West Virginia children.

Noninvasive assessment of human jawbone using ultrasonic guided waves

The problem of detecting defects in jawbones is an important problem. Existing methods based on Xrays are invasive and constrain the achievable image quality. They also may carry known risks of cancer generation or may be limited in accurate diagnosis scope. This work is motivated by the lack of current imaging modalities to accurately predict the mechanical properties and defects in jawbone. Ultrasonic guided waves are sensitive to changes in microstructural properties and thus have been widely used for noninvasive material characterization. Using these waves may provide means for early diagnosis of marrow ischemic disorders via detecting focal osteoporotic marrow defect, chronic nonsuppurative osteomyelitis, and cavitations in the mandible (jawbone). Guided waves propagating along the mandibles may exhibit dispersion behavior that depends on material properties, geometry, and embedded cavities. In this work, we present the first study in the theoretical and experimental analysis of guided wave propagation in jawbone. Semianalytical, finite-element (SAFE) method is used to analyze dispersion behavior of guided waves propagating in human mandibles. The geometry of the cross section is obtained by segmenting the computed tomography (CT) images of the jawbone. The cross section of the mandible is divided in two regions representing the cortical and trabecular bones. Each region is modeled as a linear Hookean material. The material properties for both regions are adopted from the literature. The experimental setup for the guided waves experiment is described. The results from both numerical analysis and guided waves experiment exhibit variations in the group velocity of the first arrival signal and in the dispersion behavior of healthy and defected mandibles. These results shall provide a means to noninvasively characterize the jawbone and accurately assess the bone mechanical properties. Our study is not aimed at characterizing the bone density in human mandibles. Rather, it is aimed to assess bone mechanical properties and defects that cannot be diagnosed by X-ray or other imaging modalities. This work may pave the way to the development of inexpensive noninvasive devices to detect small defects in human mandibles.

Use of conventional tomography to evaluate changes in the nasal cavity with rapid palatal expansion

INTRODUCTION

The relationship between nasal airway resistance and the use of rapid palatal expansion appliances remains controversial. The purpose of this study was to use conventional tomography to determine the anatomical changes in the nasal cavity after maxillary expansion.

METHODS

Nineteen patients (aged 8-15 years) were included in the study. Tomograms were taken before expansion (T1), immediately after expansion (T2), and 3 months after expansion (T3). Areas for the left and right anterior, middle, and posterior nasal cavity and total volume were calculated by using the computer software, AutoCAD LT 2005. Data were analyzed with paired t tests.

RESULTS

Significant increases in area were found in the anterior nasal cavity from T1 to T2 (0.85 +/- 1.19 cm2, 11.7% increase), T2 to T3 (1.18 +/- 1.2 cm2, 22.2% increase), and T1 to T3 (2.6 +/- 1.7 cm2, 35.7% increase) (P <.05). Similar increases were found in the middle and posterior nasal cavity. Significant increases in volume were found from T1 to T2 (2.1 +/- 2.7 cm3, 10.7% increase), T2 to T3 (4.9 +/- 2.3 cm3, 22.6% increase), and T1 to T3 (6.99 +/- 2.45 cm3, 27.8% increase). No significant differences were found in the area or the volume of the left and right sides of the nasal cavity. Individual variations in response to maxillary expansion were large for most of the parameters tested.

CONCLUSIONS

These data suggest that rapid palatal expansion is usually accompanied by increases in area and volume of the nasal cavity, and these changes remain stable 3 months after maxillary expansion.