Prevalence and distribution by gender of occlusal characteristics in a sample of Italian secondary school students: a cross-sectional study

Three-dimensional assessment on digital cast of spontaneous upper first molar distorotation after Ni-ti leaf springs expander and rapid maxillary expander: A two-centre randomized controlled trial

OBJECTIVE

The aim of this randomized controlled trial (RCT) was to evaluate the spontaneous distorotation of upper first permanent molars and the transverse dentoalveolar changes on digital casts in growing patients following maxillary expansion treatment using either the Leaf Expander® or the rapid maxillary expander (RME), both anchored to the deciduous second molar.

TRIAL DESIGN AND SETTING

This study was a two-arm, parallel-assignment, RCT with a dual-centre design conducted at two teaching hospitals in Italy.

PARTICIPANTS

Inclusion criteria included maxillary transverse deficiency, prepubertal development stage (cervical vertebra maturation stage [CVMS] 1-2) and early mixed dentition with fully erupted upper first permanent molars. Exclusion criteria were systemic diseases or syndromes, CVMS 3-6, agenesis of upper second premolars, unavailability of the second deciduous molar for anchorage and Class III malocclusion.

RANDOMIZATION

Patients were randomly assigned to the Leaf Expander® or RME group using a computer-generated randomization list created by a central randomization centre. Randomization was conducted immediately before the start of treatment.

INTERVENTION

The intervention involved treatment with either the Leaf Expander® or the RME. Both devices were anchored to the second deciduous molars. Following randomization, patients were further categorized based on the presence of no crossbite, unilateral crossbite or bilateral crossbite.

MAIN OUTCOME MEASURE

The primary outcome measure was the distorotation of the upper first molar (U6). Secondary outcomes included measurements of interdental linear dimensions, specifically upper inter-canine width (53-63), upper inter-molar width (MV16-MV26) and upper inter-deciduous second molar width (55-65).

BLINDING

The examiner analysing the digital casts was blinded to the treatment groups to prevent detection bias and ensure objective assessment. However, due to the nature of the intervention, blinding was not feasible for the patients and clinicians involved in administering the treatment.

RESULTS

A total of 150 patients were enrolled and randomly assigned to two groups: 75 to the Leaf Expander® group and 75 to the RME group. Recruitment started in November 2021 and was completed in November 2022. At the time of analysis, the trial was complete with no ongoing follow-ups. ANOVA tests revealed no significant differences between the three subgroups (no-cross, unilateral-cross and bilateral-cross) within both the Leaf Expander® and RME groups at T0. The Leaf Expander® demonstrated significantly greater distorotation in the unilateral crossbite subgroup compared to the RME (p = .014). In terms of total molar distorotation, the Leaf Expander® appliance showed a significantly greater effect (12.66°) compared with conventional RME (7.83°). Linear regression analysis demonstrated a significant correlation between the extent of expansion and the degree of molar rotation.

CONCLUSIONS

Maxillary expansion resulted in significant spontaneous molar distorotation when the appliance was bonded to the second deciduous molars. The Leaf Expander® exhibited significantly greater molar distorotation compared with conventional RME. The degree of molar distorotation was correlated with the extent of expansion obtained on the second deciduous molar.

TRIAL REGISTRATION

The trial was registered at ClinicalTrials.gov (ID: NCT05135962).

Skeletal and Dentoalveolar Changes in Growing Patients Treated with Rapid Maxillary Expansion Measured in 3D Cone-Beam Computed Tomography

The skeletal and dental effects of rapid maxillary expansion (RME) have been extensively studied, but high-quality research is still needed to determine the three-dimensional (3D) effects of RME. The aim of this study was to compare skeletal and dentoalveolar parameters through cone-beam computed tomography (CBCT) pre- (T1) and post-treatment (T2) with respect to RME. Twenty growing patients (mean age 10.7 years) were treated with a Hyrax-type expander. A 3D CBCT was performed at T1 and T2, measuring nasal width, maxillary width, palatal height, maxillary arch perimeter, angulation of the upper first molar, and intermolar width. The mean palatal suture opening was 2.85 ± 0.62 mm (p < 0.0001). Nasal width increased 1.28 ± 0.64 mm and maxillary width 2.79 ± 1.48 mm (p < 0.0001). In contrast, palatal height was reduced 0.65 ± 0.64 mm (p < 0.0001). Regarding arch perimeter, the radicular perimeter increased 2.89 ± 1.80 mm, while the coronal perimeter increased 3.42 ± 2.09 mm (p < 0.0001). Molar angulation increased 5.62 ± 3.20° for the right molar and 4.74 ± 2.22° for the left molar (p < 0.0001). Intermolar width increased 5.21 ± 1.55 mm (p < 0.0001). Treatment with Hyrax produced a significant opening in the mean palatal suture. Also, a significant increase in nasal width, maxillary width, arch perimeter, molar angulation, and intermolar width, and a decrease in palatal height, were observed.

Prevalence of malocclusion and orthodontic treatment needs among adolescents in Najran City, Saudi Arabia

AIM

To determine the prevalence of malocclusions and the need for orthodontic treatment in a sample of school-going adolescents in the Najran city, Kingdom of Saudi Arabia (KSA).

METHODOLOGY

This cross-sectional study was conducted among 1094 school-going Saudi male adolescents. The age range of the sampled adolescents was 13-18 years, and none of them had any history of orthodontic treatment. A survey chart related to malocclusion was designed and filled up after clinical examination by a single experienced and calibrated examiner. The need for orthodontic treatment was assessed using the Index of Orthodontic Treatment Need (IOTN).

RESULT

The present study's findings demonstrated 61.2% of the samples with Angle's Class I malocclusions, 27.5% with Class II, and 11.4% of samples with Class III malocclusion. A significant difference was observed between the different classes of malocclusion (P < 0.001). Most samples presented normal overjet, crossbite, and no reverse overjet, deep bite, or open bite. The number of samples with no treatment need was 573 (52.37%), with slight treatment in 185 (16.91%) samples, moderate treatment needs in 123 (11.24%) samples, and severe and extreme treatment needs were 109 (9.96%) and 104 (9.50%), respectively. A significant difference was observed between the samples with no or slight treatment need (grades 1 and 2), moderate need (grade 3), and definite treatment need (grades 4 and 5) (p < 0.001).

CONCLUSION

The prevalence of malocclusion and IOTNs among the sample of school-going adolescents in the Najran city was 47.63%. However, 9.63% of those samples required immediate attention for orthodontic treatment.

Comparison of the skeletal, dentoalveolar, and periodontal changes after Ni-Ti leaf spring expander and rapid maxillary expansion: a three-dimensional CBCT based evaluation

BACKGROUND

The aim of the present study was twofold:(1) three-dimensionally evaluate the quantitative skeletal and dentoalveolar changes after Ni-Ti leaf spring expander (leaf expander) and rapid maxillary expansion (RME) in mixed dentition patients;(2) analyze the modifications of the buccal alveolar bone plate of the maxillary first permanent molars.

METHODS

Patients who underwent CBCT scans before and after maxillary expansion were randomly selected from the records archived at the Department of Biomedical Surgical and Dental Sciences, University of Milan, Italy. Inclusion criteria were the following: no systemic disease or syndromes; maxillary transverse deficiencies (difference between the upper intermolar width and the lower intermolar width of at least 3 mm and/or clinical need based on radiographic evaluation), early mixed dentition with ages between 7 to 10 years old; cervical vertebra maturation stage (CVMS) 1 or 2; no pathologic periodontal status; skeletal class I or II; maxillary expander cemented on the upper second deciduous molars. Exclusion criteria were the following: patients with pubertal or post-pubertal stage of development (CVMS 3-6); late deciduous or late mixed dentition, impossibility to use the second primary molar as anchorage; skeletal class III malocclusion; craniofacial syndromes; patients unable to be followed during the treatment period. Twenty-three patients treated with Leaf Expander, 11 males (mean age 7.8 ± 0.6 years) and 12 females (mean age 8.1 ± 0.8 years), met the inclusion criteria and constituted the case group. Twenty-four (control group) treated with conventional RME, 12 males (mean age 8.4 ± 0.9 years) and 12 females (mean age 8.1 ± 0.7 years). The paired-sample T test was used for intra-group comparison to evaluate the difference between before (T1) and after (T2) maxillary expansion. Independent sample t-test was computed to perform between groups comparison of the skeletal, dentoalveolar, and periodontal changes.

RESULTS

The Leaf Expander and RME group showed a significant increase between T1 and T2 for most of the skeletal and dentoalveolar variables. Concerning the skeletal variables only the RME demonstrated a significant increase at the level of the posterior nasal (PNW) and apical base width (PABW) and maxillary mid-alveolar width (MMW). Despite this, when compare with the Leaf Expander, the RME group exhibited a statistically larger width increase for only two skeletal parameters: PNW (p = 0.03) and MMW (p = 0.02). No significant changes at the periodontal level were found in either group.

CONCLUSIONS

According to the current research, the authors confirm the effectiveness of the Leaf Expander and RME to produce similar skeletal and dentoalveolar effects in mixed dentition subjects. Moreover, the devices anchored to deciduous teeth did not reduce the thickness and height of the buccal bone at the level of the maxillary permanent first molars in either of the two groups.

Prevalence and influencing factors of malocclusion in adolescents in Shanghai, China

BACKGROUND

The main purpose of the study was to investigate the prevalence and related risk factors of malocclusion in permanent dentition among adolescents in Shanghai, and provide basic data for government's preventive strategies and intervention plans.

METHODS

1799 adolescents aged 11-15 years old from 18 middle schools in 6 districts of Shanghai were recruited to investigate oral health status and related risk factors using cluster random sampling method in 2021. Malocclusion and caries were examined by on-site inspection. The investigation criteria referred to Bjoerk and the recommendation of the WHO. The malocclusion inspection items included molars relationship, canine relationship, overbite, overjet, midline displacement, anterior crossbite, posterior crossbite, scissors bite, crowding and spacing. The subjects were asked to fill in a questionnaire including parents' education level, oral health behaviors and dietary habits. The chi-square test and logistic regression analysis were used to analyze the relationship between malocclusion and risk factors.

RESULTS

1799 adolescents were included in the study and the prevalence of malocclusion in adolescents in Shanghai was 83.5%, and the proportion of molar relationship class I, class II, and class III was 48.9%, 14.7%, and 19.0%, respectively. The most common occlusal characteristic of malocclusion was anterior crowding, followed by midline irregularities and deep overbite, with prevalence rates of 44.8%, 39.0% and 38.6%, respectively. The prevalence rate of adolescents with caries was 34.3%. Those who had dental caries and preferred soft food were more likely to have abnormal occlusal characteristics (p < 0.05).

CONCLUSION

The prevalence of malocclusion in adolescents in Shanghai is high, so it is of great significance to strengthen oral health education, allocate proper preventive strategies and carry out the early correction if necessary.

Influence of the use of remineralizing agents on the tensile bond strength of orthodontic brackets

This study aimed to evaluate the influence of the use of remineralizing agents on the tensile bond strength. The study sample consisted of 80 recently extracted molars, which were randomly divided into four experimental groups (n = 20): groups FG1 and FG30, in which fluoride varnish was used, and groups RG1 and RG30, in which Recaldent tooth mousse was used. The mesiobuccal surfaces served as experimental, and distobuccal as control (n = 80). Brackets were bonded to both surfaces and were submitted to a tension test at different time intervals (T1 and T30). Tensile bond strength (TBS) and the amount of adhesive remnant (ARI) were assessed. A statistically significantly lower mean of TBS compared to the control group was found only in the FG1 group (p < 0.001), and no significant difference was found between the other groups. The FG1 group showed significantly higher ARI scores (p < 0.001) compared to the control group. No significant difference was found between the other groups. In conclusion, bonding brackets one day after applying fluoride varnish significantly reduced the TBS, but after 30 days it was set back to an optimal value. The use of Recaldent before orthodontic treatment had no adverse effect.

Prevalence of Orthodontic Malocclusions in Healthy Children and Adolescents: A Systematic Review

The purpose of this study was to systematically review the literature regarding the prevalence of malocclusion and different orthodontic features in children and adolescents. Methods: The digital databases PubMed, Cochrane, Embase, Open Grey, and Web of Science were searched from inception to November 2021. Epidemiological studies, randomized controlled trials, clinical trials, and comparative studies involving subjects ≤ 18 years old and focusing on the prevalence of malocclusion and different orthodontic features were selected. Articles written in English, Dutch, French, German, Spanish, and Portuguese were included. Three authors independently assessed the eligibility, extracted the data from, and ascertained the quality of the studies. Since all of the included articles were non-randomized, the MINORS tool was used to score the risk of bias. Results: The initial electronic database search identified a total of 6775 articles. After the removal of duplicates, 4646 articles were screened using the title and abstract. A total of 415 full-text articles were assessed, and 123 articles were finally included for qualitative analysis. The range of prevalence of Angle Class I, Class II, and Class III malocclusion was very large, with a mean prevalence of 51.9% (SD 20.7), 23.8% (SD 14.6), and 6.5% (SD 6.5), respectively. As for the prevalence of overjet, reversed overjet, overbite, and open bite, no means were calculated due to the large variation in the definitions, measurements, methodologies, and cut-off points among the studies. The prevalence of anterior crossbite, posterior crossbite, and crossbite with functional shift were 7.8% (SD 6.5), 9.0% (SD 7.34), and 12.2% (SD 7.8), respectively. The prevalence of hypodontia and hyperdontia were reported to be 6.8% (SD 4.2) and 1.8% (SD 1.3), respectively. For impacted teeth, ectopic eruption, and transposition, means of 4.9% (SD 3.7), 5.4% (SD 3.8), and 0.5% (SD 0.5) were found, respectively. Conclusions: There is an urgent need to clearly define orthodontic features and malocclusion traits as well as to reach consensus on the protocols used to quantify them. The large variety in methodological approaches found in the literature makes the data regarding prevalence of malocclusion unreliable.

Chewing Patterns and Muscular Activation in Deep Bite Malocclusion

Background: Deep bite, a frequent malocclusion with a high relapse rate, is associated with craniofacial features that need to be considered in the course of orthodontic treatment. Methods: This study included 81 patients with deep bite malocclusion (11.4 ± 1.1 [yr.mo]; M = 32 and F = 49), and 14 age- and gender-matched controls (9.11 ± 1 [yr.mo]; M = 5 and F = 9). The patients with deep bite malocclusion were treated with functional therapy. The chewing cycles and masticatory muscle EMG activity were recorded concomitantly before treatment in both groups (n = 95). Following correction of the malocclusion, a second recording took place (n = 25). Results: The kinematic variables showed the same dependency on bolus hardness in those with deep bite and in the controls. The masticatory muscle EMG activity was increased in those with deep bite, but decreased as a result of functional treatment. The chewing patterns showed a tendency towards a reduced lateral component, which significantly increased after treatment, indicating that functional therapy impacts the neuromuscular coordination of mastication, as well as dental positioning. Conclusions: Deep bite is a complex malocclusion, involving alterations in chewing and masticatory muscle activity. Orthognathodontic treatment should not only consider and correct the teeth position, but should also address muscular hyperactivity.

Dental aspects of quality of life in orthodontic patients

Relevance. Previous studies have shown an improvement in orthodontic patients’ health-related quality of life. It is interesting to study the effect of various orthodontic appliances on the patients’ quality of life. Purpose – to study the changes in dental parameters of the quality of life in patients with malocclusion before orthodontic treatment, during treatment with metal and ceramic vestibular braces and after treatment, using removable retainers.Materials and methods. Using a validated Russian version of Oral Health Impact Profile (OHIP-49RU), we surveyed the quality of life in four patient groups: 1 - with malocclusion (n = 35), 2 – with removable retainers (n = 32), 3 – with metal brackets (n = 30), 4 – with ceramic brackets (n = 33). Statistical processing was carried out in Statistics 10. The study used descriptive statistics methods, e.g., nonparametric test methods determined the significance of sign differences: using the Kruskal-Wallis H, z tests and the χ2 test with Yates' correction.Results. OHIP-49 score analysis revealed statistically significant differences among the studied groups of pa- tients (1 - functional limitation (H = 9.15; p <0.05), 2 - physical pain (H = 13.98; p < 0.01), 3 - psychological discomfort (H = 23.04; p <0.001), 4 - physical disability (H = 24.73; p <0.001), 5 - psychological disability (H = 11.03; p < 0.05), 6 - social disability (H = 16.21; p <0.01), 7 - handicap (H = 7.91; p <0.05)).Conclusions. The patients, who had completed the orthodontic treatment and used removable retainers at night, demonstrated the best score in most sections of the questionnaire and the patients with malocclusion, who had presented to an orthodontist - the worst. Patients with the brackets had a higher score on the "Physical pain" section of the questionnaire (6.5 (3.0-8.0) with metal braces and 4.0 (2.0-7.0) with ceramic bracket system). The quality of life in patients with metal and ceramic brackets did not have statistically significant differences. 

Relationship between dental caries, oral hygiene and malocclusion among Syrian refugee children and adolescents: a cross-sectional study

BACKGROUND

Little is known about the oral disease burden in refugee children and associated risk factors. This cross-sectional study aimed to explore the oral hygiene status and prevalence of caries, and to investigate their association with malocclusion characteristics in a child refugee population.

METHODS

606 Syrian refugee children and adolescents aged 7-19 years, registered as refugees in Jordan and residing in Zaatari camp, were recruited to the study. Oral hygiene and caries status were recorded using DMFT (mean of decayed, missing, and filled permanent teeth) and OHI-S (Simplified Oral Hygiene Index) according to WHO criteria. Oral health results were then cross tabulated with previously reported malocclusion traits for the same study sample (crowding, spacing, contact point deflection and IOTN) to detect any associations. Statistical analysis was conducted using chi-square test, independent sample t-test, one-way ANOVA, Welch test and Post Hoc testing (Gabriel and Games-Howell).

RESULTS

Overall DMFT and OHI-S were 4.32 and 1.33 respectively with no difference between males and females. Around 40% of the sample showed ≥ 5 DMFT score. 96.1% of the sample either do not brush or brush occasionally: females showed better oral hygiene practices (P = 0.002). No significant differences in DMFT scores were noted for gender or age, other than the 7-9.9 year old group having significantly higher mean DMFT scores than all other age groups (P < 0.01);the mean of OHI-S was not significantly different between different age groups (P = 0.927). Subjects with malocclusion, specifically crowding, contact point deflection and IOTN grades 3, 4 and 5 had higher scores in both arches for OHI-S and DMFT than subjects without malocclusion traits, although this was not statistically significant for DMFT scores. Overall, patients with generalized spacing had a significantly lower OHI-S score than those without spacing (P = 0.021). Significant correlations were found between parameters of intra-arch and inter-arch relationships and oral health indices (DMFT and OHI-S).

CONCLUSION

Malocclusion may increase the risk of caries and periodontal disease; the magnitude of this risk is amplified in populations with poor oral health and limited access to oral healthcare services, highlighting the need for preventive and curative oral health programs.

Posterior crossbite with mandibular asymmetry treated with lingual appliances, maxillary skeletal expanders, and alveolar bone miniscrews

Posterior crossbite and mandibular asymmetry affect esthetics and function. We report treatment of 3 patients with posterior crossbite with mandibular asymmetry but different anteroposterior and vertical characteristics. Treatment methods included maxillary skeletal expander, miniscrews, and lingual appliances. The results show that by using these appliances, ideal transverse, anteroposterior, and vertical control is possible in patients who have concerns about the esthetics of buccal appliances. Lingual appliances can provide satisfying results when combined with a maxillary skeletal expander and miniscrews in complex patients.

Malocclusion severity and its associations with oral health-related quality of life in an adult population

AIM

The aim of this study was to investigate malocclusion severity and its associations with oral health-related quality of life (OHRQoL) among middle-aged adults.

MATERIALS AND METHODS

The study material consisted of 1786 subjects from the Northern Finland Birth Cohort 1966 who attended dental and oral examination as part of the 46-year-old follow-up study. Malocclusion severity was assessed using the Dental Health Component (DHC) of the Index of Orthodontic Treatment Need (IOTN) and the Peer Assessment Rating index (PAR) from digital 3D dental models. Participants also answered a questionnaire including the Oral Health Impact Profile (OHIP-14) and a question on their satisfaction with occlusal function. Differences between malocclusion severity groups were evaluated for both genders separately. For adjusted models, multivariate Poisson regression models were conducted.

RESULTS

In this study population, 31.3% had great or very great orthodontic treatment need according to DHC and the mean PAR total score was 22.05. The most severe malocclusions were associated with OHRQoL, especially the psychosocial and handicap dimensions, and satisfaction with occlusal function. There was a significant difference between genders, men having more severe malocclusion but women reporting more OHRQoL impacts.

CONCLUSION

One third of the study population were considered to have severe malocclusion. There was an association between malocclusion severity and OHRQoL in adult population, particularly in women.

Characterisation of anterior open bite in primary school-aged children: A preliminary study with artificial neural network analysis

BACKGROUND

Non-nutritive sucking habits, bottle feeding, and facial hyperdivergency have been suggested as the influencing factors of anterior open bite (AOB). There was inconsistent reporting of prevalence and a gap of knowledge in the literature.

AIM

The aim of this study was to investigate the prevalence of AOB in 7- to 12-year-olds, with a special interest to characterise the determinants of this malocclusion.

DESIGN

A sample of 203 children aged 7 to 12 years were selected from a primary school in regional Australia. The legal guardian of each child completed a self-administered questionnaire. Data were assessed using methods of univariate statistics and neural analysis.

RESULTS

The prevalence of AOB and thumb sucking was 24.1% and 23.2%, respectively. AOB was associated with the habit (correlation = 0.754) and duration (correlation = 0.574) of thumb sucking. Age, gender, birth order, feeding modality, sleep patterns, history of orthodontic treatment and tonsil, adenoid or grommet surgery, and parents' level of education were not related to AOB (correlation absolute value ≤ 0.474).

CONCLUSIONS

Thumb sucking, specifically for prolonged duration, increases the risk of development of AOB. Cessation of thumb sucking habits should be encouraged at an early age to avoid the development of AOB.

Prevalence of malocclusion and assessment of orthodontic treatment needs among Syrian refugee children and adolescents: a cross-sectional study

Background

There is a scarcity of data concerning the prevalence and pattern of malocclusion and orthodontic treatment needs in Syrian refugee. In this study, extra and intra-oral features of malocclusion and the dental health component of the Index of Orthodontic Treatment Need (IOTN) were reported.

Methods

Examination of 606 Syrian children/adolescents refugees attending Zaatari clinic was carried out (males = 280, females = 326, mean age = 11.84 ± 2.1 years). Subjects not within the age limit, with a history of orthodontic treatment, or with craniofacial anomalies were excluded. Both extra and intra-oral features of malocclusion were assessed. Intra-oral features included inter- and intra-arch occlusal characteristics: crowding, spacing, crossbite, overjet, overbite, molar and canine relationship, incisor relationship, and centerline shift. In addition, the dental health component (DHC) of the Index of Orthodontic Treatment Need (IOTN) was recorded. Gender and age variations in malocclusion characteristics and IOTN grading were tested using chi-square and nonparametric tests respectively (P < 0.05).

Results

The prevalence of malocclusion was 83.8% (52.6% class I, 24.2% class II, 7% class III). The most common features of malocclusion were crowding (71.1%) followed by centerline shift (52.1%), increased overjet (36.1%), high vertical proportions (34%) and deep overbite (31.2%); there were significant gender and age differences for a number of occlusal traits. The prevalence of moderate to severe need for orthodontic treatment was 67.7%.

Conclusions

This study provides baseline data on the prevalence of malocclusion in Syrian refugee children/adolescents in Zaatari camp where data concerning oral health of this population are lacking. The prevalence of orthodontic treatment need was high warranting the need for a comprehensive interceptive orthodontic program to prevent increasing oral health problems in the future. This high burden of oral diseases has a negative financial impact on the hosting country which can be reduced through public health interventions and implementing community-based dental healthcare for this underprivileged population.

Are the Reasons Why Patients Are Referred for an Orthodontic Visit Correct?

Who does refer patients for an orthodontic consultation? Which are the main reasons for the referral? Does the visit of the orthodontic specialist confirm these reasons or reveal undiagnosed problems? Is there the risk that only evident dental problems are addressed, while craniofacial malformations remain underdiagnosed? This cross-sectional epidemiologic study aims to answer these questions, analysing the clinical data collected during the orthodontic visits of 500 Caucasian young patients referred to a public health structure of northern Italy. All patients were visited by the same expert specialist in orthodontics. Clinical data were collected, analysing both dental and skeletal features. The reasons for the referral of the visit were analysed and compared with the specialistic diagnoses. In our sample, dentists, relatives/friends and paediatricians were the major source of the referrals, followed by family doctors and other facial specialists. In most cases, the reasons for the referral were dental irregularities, but approximately 80% of dental irregularities were associated with undiagnosed facial dysmorphism. Skeletal facial anomalies need an early diagnosis to prevent the development of severe facial malformations that would require invasive and expensive treatments. These findings reveal poor diagnostic skills regarding skeletal anomalies in dentists and paediatricians and the need for better specific training.

Risk assessment of orthodontic anomalies in children in suburban areas

Introduction: Orthodontic anomalies are very common both in the world and in our country. The etiology of orthodontic anomalies is multifactorial, complex and conditioned by numerous genetic and non-genetic factors: endogenous and exogenous. Prevention of orthodontic anomalies is possible if we have an insight into the most common etiological factors. Goal: To assess the frequency of individual etiological factors and assess the overall risk of orthodontic anomalies in children in suburban environments. Materials and methods: The research was conducted on 115 children, first grade elementary school pupils (28.68% of all 1st grade students), average age of 6.8 years, from 4 settlements around Novi Sad: Kisač, Kać, Veternik, and Futog. The research was conducted in the form of anonymous rounding surveys for parents with a preliminary explanation of the questions asked. The questions included etiological factors for the occurrence of orthodontic anomalies (diseases in pregnancy, childbirth, breastfeeding, supplementation and feeding, type of pacifier, position of the bottle when eating, bad habits, position when sleeping, position of arms when sleeping in relation to the jaw, pillow height, mouth breathing, orthodontic anomalies in parents). Results: Results indicate the following etiological factors as the most common: supplementary feeding and bottle feeding (in 41.74% of cases), breastfeeding from 0 to 6 months (40.87% of respondents) and mouth breathing (in 24.35% of children). In the examination of the total risk for orthodontic anomalies, low-risk was found in 95.65% of cases, medium-risk in 4.35% (in Kisac 9.38%, in Kać 2.94%, in Veternik 4.35%, in Futog 0% of children), while there were no high-risk respondents. Conclusion: Preventive measures should be aimed at educating mothers about the need and benefits of a natural way of breastfeeding and of using a spoon for supplementation and feeding.

Gender-specific associations of malocclusion traits with oral health-related quality of life in a Finnish adult population

AIM

The aim of this cross-sectional study was to investigate gender-specific associations of different malocclusion traits with oral health-related quality of life (OHRQoL) among Finnish adults.

MATERIAL AND METHODS

The study material comprised 1885 subjects from the Northern Finland Birth Cohort 1966. A clinical oral examination including registration of occlusion was carried out in connection with a 46-year follow-up examination. The 14-item Oral Health Impact Profile (OHIP-14) was used to measure OHRQoL. Subgroups with increased/decreased overjet, deep bite, open bite, lateral crossbite, and scissor bite were selected for further analysis. Subjects with normal occlusion were selected to form the normal occlusion group. Differences between subgroups and the normal occlusion group were evaluated for both genders separately. Education, number of teeth, caries, and orthodontic treatment history were chosen as confounding variables. Multivariate Poisson regression analyses were conducted to assess the effect of independent variables on OHRQoL.

RESULTS

After adjustments, decreased overjet, open bite, and scissor bite were associated with higher OHIP severity in women (P < 0.01). In men, deep bite was associated with higher OHIP severity (P = 0.007). Different malocclusion traits had associations with some OHIP dimension either in men or women. Orthodontic treatment history had a positive effect on OHRQoL in both genders.

CONCLUSION

The associations of malocclusion traits with OHRQoL differed between genders, with women reporting more impacts. Deviations from normal occlusion were generally found to have a negative impact on OHRQoL, but most of the adults with malocclusion seem to adapt to their condition.

Mechanical properties of the NiTi Memoria Leaf Spring Activated Expander (NiTi MLSAE) for maxillary transverse discrepancy correction: An in-vitro study

Background

To determine the mechanical properties of the NiTi Memoria® Leaf Spring Activated Expander (NiTi MLSAE) in two forms, unaltered (unbent) and altered (bent) to mimic clinical use.

Material and Methods

This in-vitro pilot study was conducted using eight NiTi MLSAE expanders (American Tooth Industries, Oxnard, California) representing four force magnitudes: 10mm 500g, 10mm 900g, 6mm 450g and 6mm 900g models. Two experiments were performed: the first tested the expanders in their unbent form and the second tested them after they were bent by one experienced technician. All expanders were adapted to a standard three dimensional printed maxillary study model. A Dillion Quantrol 500N (110lbf) load cell and a custom-made fixturing apparatus was used to determine the amount of expansive forces delivered. Prior to testing, the ligation compressing the NiTi MLSAE leaves was cut to allow the appliances to expand to their original form. Emperor™ (force) Software was used to measure the expansion forces.

Results

The average expansion forces generated by the expanders were: unaltered = 897.4g (8.8N) and bent = 877.0g (8.6N) for the 10mm 900g model, unaltered = 489.5g (4.8N) and bent = 479.3g (4.7N) for the 10mm 500g model, unaltered = 458.9g (4.5N) and bent = 438.5g (4.3N) for the 6mm 450g model, and unaltered = 805.6g (7.9N) and bent = 785.2g (7.7N) for the 6mm 900g model.

Conclusions

Regardless of whether the expander was straight or bent, the forces generated by the 10mm 900g, 10mm 500g and 6mm 450g Ni-Ti MLSAEs correlated with the benchmark study conducted by the manufacturer. However, the forces generated by the 6mm 900g Ni-Ti MLSAE were less than the data published by the manufacturer. Binding was observed when the expanders were manipulated to mimic clinical use, and this may account for the reported lower expansion force.

Key words:Maxillary expansion, NiTi, posterior crossbite, malocclusion, maxillary transverse discrepancy.

Association between malocclusion and orofacial myofunctional disorders of pre-school children in Latvia

OBJECTS

Abnormal use of muscles of tongue and lips is called orofacial myofunctional disorders (OMD). In this study, we aimed to investigate the interrelation between occlusal findings and OMD in primary and mixed dentition and to find out the reasons for malocclusions, and the effect modification of these associations by the number of sources that parents used to receive the information on child oral health issues (NSI).

SETTING AND SAMPLE POPULATION

Cross-sectional study was performed in one kindergarten in Latvia (cluster sampling). The study sample comprised 141 children-mothers' pairs of pre-school children aged 4-7 years.

MATERIALS AND METHODS

Children' myofunctional situation, occlusion and speech defects were assessed during an examination. Children's mothers were interviewed on their socio-demographic situation, feeding and habits of the child, history of diseases and NSI. Multiple logistic regression models adjusted for lip power, swallowing, breathing and speech cases of long respiratory diseases, age and gender were built to investigate associations between the types of occlusion and OMD/health characteristics. Effect modification of these associations by NSI was analysed.

RESULTS

Types of occlusion associated with OMD/health characteristics were as follows: normal occlusion with prolonged respiratory diseases (odds ratio, OR = 0.345 [95% confidence interval, CI 0.16; 0.75]); combined type with tongue thrust habits (OR = 3.11 [0.99; 9.90]), lip-closing strength (OR = 0.99 [0.98; 0.99]); and cross-bite with speech (OR = 3.55 [1.07; 11.78]). These associations remained stable when parents used two or less sources of information on children's oral health.

CONCLUSIONS

To facilitate occlusal stability, early interdisciplinary examinations should be performed to prevent time-consuming and cost-consuming treatment.

Global distribution of malocclusion traits: A systematic review

OBJECTIVE

Considering that the available studies on prevalence of malocclusions are local or national-based, this study aimed to pool data to determine the distribution of malocclusion traits worldwide in mixed and permanent dentitions.

METHODS

An electronic search was conducted using PubMed, Embase and Google Scholar search engines, to retrieve data on malocclusion prevalence for both mixed and permanent dentitions, up to December 2016.

RESULTS

Out of 2,977 retrieved studies, 53 were included. In permanent dentition, the global distributions of Class I, Class II, and Class III malocclusion were 74.7% [31 - 97%], 19.56% [2 - 63%] and 5.93% [1 - 20%], respectively. In mixed dentition, the distributions of these malocclusions were 73% [40 - 96%], 23% [2 - 58%] and 4% [0.7 - 13%]. Regarding vertical malocclusions, the observed deep overbite and open bite were 21.98% and 4.93%, respectively. Posterior crossbite affected 9.39% of the sample. Africans showed the highest prevalence of Class I and open bite in permanent dentition (89% and 8%, respectively), and in mixed dentition (93% and 10%, respectively), while Caucasians showed the highest prevalence of Class II in permanent dentition (23%) and mixed dentition (26%). Class III malocclusion in mixed dentition was highly prevalent among Mongoloids.

CONCLUSION

Worldwide, in mixed and permanent dentitions, Angle Class I malocclusion is more prevalent than Class II, specifically among Africans; the least prevalent was Class III, although higher among Mongoloids in mixed dentition. In vertical dimension, open bite was highest among Mongoloids in mixed dentition. Posterior crossbite was more prevalent in permanent dentition in Europe.

The prevalence of malocclusion and orthodontic treatment need in Omani adolescent population

OBJECTIVE:

To determine the prevalence of malocclusion and orthodontic treatment need in a sample of Omani adolescents aged 11–16 years.

MATERIALS AND METHODS:

The total sample included 854 adolescents with 387 boys and 467 girls between the age of 11 and 16 years with no previous orthodontic treatment history. The study design was cross-sectional. The parameters studied were skeletal relationship, lip competency, teeth impactions, missing teeth, contact point displacement, crowding, spacing, incisors and molars classification, overjet, overbite, crossbite, oral hygiene and caries. The Index of Orthodontic Treatment Need (IOTN) was used to study the need for orthodontic treatment for the total sample.

RESULTS:

There was a high prevalence of Class I jaw relationship (86.2%). About 81.6% of the sample studied had Class I molar relationship and 73.8% had Class I incisors relationship. About 61.4% of the sample had no contact displacement, while 5.2% had contact displacement >4 mm. Severe crowding in the maxilla was found in 2.3% while spacing was found in 24.2%. Around 11% of the sample studied had Class II div 1 incisors relationship, 13.5% Class III and only 1.8% had Class II div 2 incisors relationship. Only 8.6% of the sample studied had an overjet >6 mm while 16.3% had a deep bite and 0.2% had anterior open bite of >4 mm. Teeth impaction was found in 11.7% while permanent missing teeth was present in 1.8%. The results showed that 13.9% had a very great need for treatment while 43.2% of the sample did not need any treatment.

CONCLUSION:

Among the Omani adolescents, there was a high prevalence of Class I jaw relations and Class I molar relationship. The prevalence of malocclusion and treatment need in Omanis shows some variation when compared to other ethnicities.

Malocclusion prevalence and orthodontic treatment need in central Anatolian adolescents compared to European and other nations' adolescents

Objective:

To determine the prevalence of malocclusion and orthodontic treatment need in a large sample of Central Anatolian adolescents and compare them with European-other nations' adolescents.

Methods:

The sample included 1125 boys and 1204 girls aged between 12 and 16 years with no previous orthodontic treatment history. Occlusal variables examined were molar relationship, overjet, overbite, crowding, midline diastema, posterior crossbite, and scissors bite. The dental health (DHC) and aesthetic components (AC) of the Index of Orthodontic Treatment Need (IOTN) were used as an assessment measure of the need for orthodontic treatment for the total sample.

Results:

The results indicated a high prevalence of Class I (34.9%) and Class II, Division 1 malocclusions (40.0%). Moreover, increased (18%) and reduced bites (14.%), and increased (25.1%) and reversed overjet (10.%) were present in the sample.

Conclusion:

Using the DHC of the IOTN, the proportion of subjects estimated to have great and very great treatment need (grades 4 and 5) was 28.%. However, only 16.7% of individuals were in need (grades 8-10) of orthodontic treatment according to the AC.

The Prevalence of Major Types of Occlusal Anomalies among Saudi Middle School Students

INTRODUCTION

Malocclusion is the most common dental anomaly among children and adolescents. Accordingly, this study was conducted to investigate the prevalence of major types of occlusal anomalies in permanent dentition among Saudi Arabian middle school adolescent students seeking orthodontic treatment in Jeddah.

MATERIALS AND METHODS

The sample comprised 150 males and 150 females with mean age of 14.25 (±1.09) for both males and females. Data were registered using the Bjork method.

RESULTS

The results of the study showed that postnormal occlusion, prenormal occlusion, and bimaxillary protrusion represented 22, 14.7, and 8.3% of the studied sample respectively. Moderate and severe overjet accounted for 24.7 and 5.7% and for overbite 28 and 13% respectively. Midline deviation was detected in 25.3% of the sample. Mild, moderate, and severe maxillary and mandibular crowding represented 10, 27.3, and 10% and 13, 40, and 9.7% respectively.

CONCLUSION

The prevalence of occlusal anomalies was 90% and some occlusal anomalies were higher in females.

CLINICAL SIGNIFICANCE

The prevalence of occlusal anomalies in Saudi Arabian middle school students necessitates the demand for obtaining baseline data for planning orthodontic services.

Prevalence of Posterior Crossbite for Orthodontic Treatment Timing

OBJECTIVE

To evaluate the prevalence and distribution of posterior crossbite in different dentition stages in a Turkish sample.

STUDY DESIGN

1554 subjects (843 girls, 711 boys) aged 4-25 years were evaluated to determine the prevalence of posterior crossbite in a Turkish sample. The subjects were classified according to four dentition stages (primary, early mixed, late mixed and permanent) and transversal occlusal status. The statistical evaluation was done by Chi-square, Fischer exact tests.

RESULTS

Bilateral and unilateral crossbite on the right and left sides had the highest frequency in the permanent dentition (51.0%, 47.3%, and 53.6%; respectively). No significant differences were found between unilateral (right and left) and bilateral crossbite with regard to dentition stages. No significant differences were found between unilateral right or left side posterior crossbite with regard to dentition stages.

CONCLUSION

An increasing trend in the prevalence of posterior crossbite was observed from the primary dentition towards permanent dentition in this study.

Unilateral Posterior Crossbite is Not Associated with TMJ Clicking in Young Adolescents

Unilateral posterior crossbite has been considered as a risk factor for temporomandibular joint clicking, with conflicting findings. The aim of this study was to investigate a possible association between unilateral posterior crossbite and temporomandibular disk displacement with reduction, by means of a survey carried out in young adolescents recruited from three schools. The sample included 1291 participants (708 males and 583 females) with a mean age of 12.3 yrs (range, 10.1–16.1 yrs), who underwent an orthodontic and functional examination performed by two independent examiners. Unilateral posterior crossbite was found in 157 participants (12.2%). Fifty-three participants (4.1%) were diagnosed as having disk displacement with reduction. Logistic regression analysis failed to reveal a significant association between unilateral posterior crossbite and disk displacement with reduction (odds ratio = 1.3; confidence limits = 0.6–2.9). Posterior unilateral crossbite does not appear to be a risk factor for temporomandibular joint clicking, at least in young adolescents.

Prevalence of Malocclusion among 10-12-year-old Schoolchildren in Kozhikode District, Kerala: An Epidemiological Study

Background: A malocclusion is an irregularity of the teeth or a malrelationship of the dental arches beyond the range of what is accepted as normal.

Objectives: To determine the prevalence of malocclusion in children aged 10-12 years in Kozhikode district of Kerala, South India.

Materials and methods: A descriptive cross-sectional study was conducted among schoolchildren aged 10-12 years in six schools in Kozhikode district of Kerala, South India. A total of 2,366 children satisfied the inclusion criteria. Occlusal characteristics like crossbite, open bite, deep bite, protrusion of teeth, midline deviations, midline diastema and tooth rotation were recorded. The data were tabulated and analyzed using Chi-square test.

Results: The results revealed that the overall prevalence of malocclusion was 83.3%. Of this, 69.8% of the children had Angle’s class I malocclusion, 9.3% had class II malocclusion (division 1 = 8.85%, division 2 = 0.5%) and 4.1% had class III malocclusion; 23.2% showed an increased overjet (>3 mm), 0.4% reverse overjet, 35.6% increased overbite (>3 mm), 0.29% open bite, 7.2% crossbite with 4.6% crossbite of complete anterior teeth, 63.3% deviation of midline, 0.76% midline diastema and 3.25% rotated tooth. No significant differences in gender distributions of malocclusions were noted except for increased overjet and overbite.

Conclusion: There is high prevalence of malocclusion among schoolchildren in Kozhikode district of Kerala. Early interception and early correction of these malocclusions will eliminate the potential irregularities and malpositions in the developing dentofacial complex.

How to cite this article: Narayanan RK, Jeseem MT, Kumar TVA. Prevalence of Malocclusion among 10-12-year-old Schoolchildren in Kozhikode District, Kerala: An Epidemiological Study. Int J Clin Pediatr Dent 2016;9(1):50-55.

The prevalence of malocclusion and oral habits among 5-7-year-old children

BACKGROUND

Digit sucking, tongue thrust swallowing, and mouth breathing are potential risk factors for development of malocclusion. The purpose of this study was to verify the prevalence of different occlusal traits among 5-7-year-old children and assess their relationship with oral habits.

MATERIAL AND METHODS

The study included 503 pre-school children (260 boys and 243 girls) with a mean age of 5.95 years. Different occlusal traits were verified by intraoral examination. Oral habits were diagnosed using data gathered from clinical examination of occlusion and extra-oral assessment of the face, combined with a questionnaire for parents.

RESULTS

The study demonstrated that 71.4% of the children presented with 1 or more attributes of malocclusion and 16.9% had oral habits. The vertical and sagittal malrelation of incisors, as well as spacing, were the predominant features. This study showed that digit suckers have higher incidence of anterior open bite (P=0.013) and posterior crossbite (P=0.005). The infantile type of swallowing demonstrated strong association (P=0.001) with anterior open bite.

CONCLUSIONS

Non-nutritive sucking habits and tongue thrust swallowing are significant risk factors for the development of anterior open bite and posterior crossbite in pre-school children.

Bony adaptation after expansion with light-to-moderate continuous forces

INTRODUCTION

The purpose of this study was to evaluate the biologic response of dentoalveolar bone to archwire expansion with light-to-moderate continuous forces.

METHODS

With a split-mouth experimental design, the maxillary right second premolars of 7 adult male dogs were expanded for 9 weeks using passive self-ligating brackets (Damon Q; Ormco, Orange, Calif) and 2 sequential archwires (0.016 × 0.022-in copper-nickel-titanium alloy, followed by 0.019 × 0.025-in copper-nickel-titanium alloy). Intraoral and radiographic measurements were made to evaluate tooth movements and tipping associated with expansion; archwire forces were measured using a force gauge. Microcomputed tomography was used to compare buccal bone height, total tooth height, total root height, and buccal bone thickness. Bone formation was evaluated histologically using tetracycline and calcein fluorescent labels and hematoxylin and eosin stains.

RESULTS

Buccal expansion was produced by forces between 73 and 178 g. Compared with the control side, which showed no tooth movement, the experimental second premolars were expanded by 3.5 ± 0.9 mm and tipped by 15.8°. Buccal bone thickness was significantly thinner (about 0.2 mm) in the coronal aspects and significantly thicker (about 0.9 mm) in the apical aspects over the mesial roots. The tipping and expansion significantly (P <0.05) reduced buccal bone height (ie, caused dehiscences) at the mesial (about 2.9 mm) and distal (about 1.2 mm) roots. Bony apposition occurred on the trailing edges of tooth movement and on the leading edges of the second premolar apices. The axial microcomputed tomography slices indicated, and the bone histomorphometry and histology demonstrated, newly laid-down bone on the periosteal side of the buccal cortical surfaces. Ordered osteoblast aggregation was also evident on the periosteal surfaces of buccal bone, just cervical to the apparent center of rotation of the tooth. Tooth and root heights showed no significant differences between the experimental and control second premolars.

CONCLUSIONS

Buccal expansion with light-to-moderate continuous forces produced 3.5 mm of tooth movement, uncontrolled tipping, and bone dehiscence, but no root resorption. Bone formation on the periosteal surfaces of cortical bone indicates that apposition is possible on the leading edge of tooth movements.

Prevalence of malocclusion among adolescents in South Indian population

Objective:

To record prevalence of malocclusion among 2,400 adolescents in Karnataka state, India and to define difference in malocclusion status in urban and rural population.

Design:

Randomized cross-sectional study.

Setting:

School students of Karnataka state, 24 August 2011 to 30 March 2012.

Participants:

School students in the age group of 13-17 years.

Materials and Methods:

Each individual was assessed for occlusal traits - sagittal occlusion, overjet, overbite, crowding, midline diastema, and crossbite.

Statistical Analysis Used:

Examinations were computerized and analyzed using Statistical Package for Social Sciences version 16. Chi-square test was used for computing statistical significance.

Results:

87.79% of population had malocclusion. Out of which 89.45% had class I, 8.37% had class II, and 2.14% had class III malocclusion. Normal overjet and overbite was seen in 48.22 and 49.87% of subjects, respectively. Frequency of crowding was 58.12% and 15.43% of subjects had midline diastema. Anterior crossbite was present in 8.48% and posterior crossbite in 0.99%. Urban population had twice the class II sagittal occlusion, and increased overjet as compared to rural population.

Conclusions:

Malocclusion is widely spread among population of Karnataka state, with greater prevalence in urban population. Early exfoliation of deciduous teeth and refined diet can be considered as viable etiological factors.

Possible causal relationships between competitive swimming in growing age and three-dimensional dentoalveolar development

Background

The aim of this study was to investigate possible links between competitive swimming during the growth phase and the development of the dentoalveolar arches.

Methods

The study sample included 100 swimmers and a control group of 100 age-matched non-swimmers who had never practised swimming or related sports. Subjects who had had previous orthodontic treatment were excluded. Overjet, overbite, sagittal and transverse parameters, arch dimension, crowding and oral habits were recorded.

Results

In the swimmers, there was a significantly higher frequency of molar symmetry (P = 0.04), together with a greater number of Class I subjects. The overjet in the swimmers was mainly normal, but the arch dimensions were significantly wider (+10% in the upper arch; P < 0.001). Similarly, the swimmers showed significantly less severe crowding (P < 0.001) and significantly reduced oral habits (P < 0.001).

Conclusions

Our data and analysis demonstrate that competitive swimming during the growth phase has a favourable effect on dental arch development in the sagittal, vertical and transverse planes.

Early treatment of posterior crossbite--a randomised clinical trial

Background

The aim of this randomised clinical trial was to assess the effect of early orthodontic treatment in contrast to normal growth effects for functional unilateral posterior crossbite in the late deciduous and early mixed dentition by means of three-dimensional digital model analysis.

Methods

This randomised clinical trial was assessed to analyse the orthodontic treatment effects for patients with functional unilateral posterior crossbite in the late deciduous and early mixed dentition using a two-step procedure: initial maxillary expansion followed by a U-bow activator therapy. In the treatment group 31 patients and in the control group 35 patients with a mean age of 7.3 years (SD 2.1) were monitored. The time between the initial assessment (T1) and the follow-up (T2) was one year. The orthodontic analysis was done by a three-dimensional digital model analysis. Using the ‘Digimodel’ software, the orthodontic measurements in the maxilla and mandible and for the midline deviation, the overjet and overbite were recorded.

Results

Significant differences between the control and the therapy group at T2 were detected for the anterior, median and posterior transversal dimensions of the maxilla, the palatal depth, the palatal base arch length, the maxillary arch length and inclination, the midline deviation, the overjet and the overbite.

Conclusions

Orthodontic treatment of a functional unilateral posterior crossbite with a bonded maxillary expansion device followed by U-bow activator therapy in the late deciduous and early mixed dentition is an effective therapeutic method, as evidenced by the results of this RCT. It leads to three-dimensional therapeutically induced maxillary growth effects. Dental occlusion is significantly improved, and the prognosis for normal craniofacial growth is enhanced.

Trial registration

Registration trial DRKS00003497 on DRKS

Odontostomatologic involvement in juvenile localised scleroderma of the face

AIM

Localised scleroderma of the face (LSF) can lead to significant aesthetical and functional abnormalities. Despite their quite frequent clinical observation, the odontostomatologic complications are not thoroughly described. Aim of the study was to describe the clinical features of the most frequent odontostomatologic abnormalities of LSF and to propose clinical and radiologic criteria for the assessment and follow-up of these complications.

METHODS

  We performed a cross-sectional, multicenter study involving a multidisciplinary team formed by paediatric rheumatologists, orthodontists and radiologists. Patients with a diagnosis of LSF underwent a comprehensive rheumatologic evaluation, dental examination, conventional radiology (orthopantomography, teleradiography) and cone beam computed tomography.

RESULTS

16 patients, nine F, seven M, aged 6.5-21.9 years, were investigated. The mean disease duration was 7.7 years, 62.5% had extracutaneous complications. All patients reported at least one odontostomatologic complication. The main alterations were: malocclusion (94%), overgrowth tendency of the anterior lower third of the face (82%), gnatologic alterations (69%), dental anomalies (63%), skeletal asymmetry (56%), bone involvement (50%) and temporomandibular joint involvement (19%).

CONCLUSIONS

We found a high incidence of odontostomatologic abnormalities in LSF. Cone beam computed tomography represents a new feasible technique to evaluate and monitor soft and hard tissue changes in LSF. The observed findings highlight the importance of a multidisciplinary and standardised management of this challenging and rare condition.

Malocclusion Pattern (Angle's) in Mauritian Orthodontic Patients

The aim of the study was to assess the pattern of malocclusion in different ethnic group of Mauritian population visiting the Orthodontic Department at Mauras College of Dentistry and Hospital, Republic of Mauritius. The study population comprised of 624 patients who visited the orthodontic department during 2010. The clinical examination was conducted by a well-calibrated orthodontist. The data were recorded in the case sheets and was analyzed for presence of angles class I, class II, and class III malocclusion in both male and female patients of Asian, African, Caucasian, and Chinese ethnicity aged 5-55 years. Malocclusion was found to be high in females compared to males. 414 patients (150 male + 264 female) presented with class I, 182 patients (52 male + 130 female) presented with class II, and 28 patients (12 male + 16 female) presented with class III. Asian ethnic group were more affected and patient seeking orthodontic treatment was high in 11-15 years age group.

Transverse changes determined by rapid and slow maxillary expansion--a low-dose CT-based randomized controlled trial

OBJECTIVES

To compare transverse skeletal changes produced by rapid (RME) and slow (SME) maxillary expansion using low-dose computed tomography. The null hypothesis was that SME and RME are equally effective in producing skeletal maxillary expansion in patients with posterior crossbite.

SETTING AND SAMPLE POPULATION

This study was carried out at the Department of Oral Sciences, University of Naples Federico II, Italy. Twelve patients (seven males, five females, mean age ± SD: 10.3 ± 2.5 years) were allocated to the SME group and 14 patients (six males, eight females, mean age ± SD: 9.7 ± 1.5 years) to the RME group.

MATERIALS AND METHODS

All patients received a two-band palatal expander and were randomly allocated to either RME or SME. Low-dose computed tomography was used to identify skeletal and dental landmarks and to measure transverse maxillary changes with treatment.

RESULTS

A significant increase in skeletal transverse diameters was found in both SME and RME groups (anterior expansion = 2.2 ± 1.4 mm, posterior expansion = 2.2 ± 0.9 mm, pterygoid expansion = 0.9 ± 0.8 mm). No significant differences were found between groups at anterior (SME = 1.9 ± 1.3 mm; RME = 2.5 ± 1.5 mm) or posterior (SME = 1.9 ± 1.0 mm; RME = 2.4 ± 0.9 mm) locations, while a statistically significant difference was measured at the pterygoid processes (SME = 0.6 ± 0.6 mm; RME = 1.2 ± 0.9 mm, p = 0.04), which was not clinically relevant.

CONCLUSION

Rapid maxillary expansion is not more effective than SME in expanding the maxilla in patients with posterior crossbite.

Sex differences in esthetic treatment needs in American black and white adolescent orthodontic patients

OBJECTIVE

To test whether the severity of malocclusions in adolescents who actually entered orthodontic treatment is different between the sexes, as this might explain the preponderance of girls in orthodontic practices.

MATERIALS AND METHODS

Severity was gauged with the 10-grade esthetic component of the Index of Orthodontic Treatment Need (IOTN) scored on the pretreatment intraoral photographs (n = 562) in a university-based specialty program. The samples of American White (n = 401) and American Black (n = 161) adolescents were free of craniofacial defects. Nonparametric statistics were used for analysis.

RESULTS

There is a significant sex difference in the IOTN in White teenagers due to milder, more esthetic cases among the girls. No sex difference occurs in the sample of Blacks, with both sexes having IOTN scores on a par with White males. The severity of malocclusion is independent of the age at start of treatment (within range of 12 to 19 years).

CONCLUSIONS

Greater subjective self-perceptions of occlusal issues seem to account for the preponderance of White girls in the patient pool, though why the sex difference is not evident in American Blacks is complex. We speculate that sex differences are larger in private practices, since there are fewer selection criteria for entering treatment.

Prevalence of orthodontic treatment need in southern Italian schoolchildren

The present survey was performed to determine orthodontic treatment need in a large sample (n = 703) of 12-year-old schoolchildren from the southern part of Italy. The sample comprised 331 males (47 per cent) and 372 females (53 per cent), all orthodontically untreated. Two examiners, who had been previously trained in the use of occlusal indices, screened all the schoolchildren. The prevalence rates for the Dental Health Component (DHC) of the Index of Orthodontic Treatment Need (IOTN) as well as for occlusal features (Angle Class, overjet, overbite, crowding, posterior crossbite) were calculated for the total sample. The IOTN grades were statistically compared in the two genders using the chi-square test. The findings indicated that this southern Italian school population showed a rather low prevalence rate for objective need for treatment (grades 4 and 5; 27.3 per cent of the total sample). This prevalence rate is generally lower than those reported in northern and central European countries (Sweden, Germany, and UK) but slightly greater than those in France. No significant differences in the DHC grades of the IOTN were found between genders. Among the occlusal features diagnosed in the subjects examined, a high prevalence rate was found for crowding (45.9 per cent). Moreover, posterior crossbites and Class III malocclusions, which would presumably have benefited from early orthodontic intervention, were still present in 14.2 and 4.3 per cent of the students, respectively.

Prevalence of malocclusion and its relationship with socio-demographic factors, dental caries, and oral hygiene in 12- to 14-year-old Tanzanian schoolchildren

The aim of this study was to assess the prevalence of malocclusion and its association with socio-demographic characteristics, caries experience, and level of oral hygiene in 12- to 14-year-old schoolchildren residing in two socio-economically different districts of Tanzania. A total of 1601 children (mean age 13 years, 60.5 per cent girls) attending 16 primary schools in Kinondoni and Temeke districts participated in a clinical examination and were interviewed in school settings. Chi-square and multiple logistic regression models were used to test for statistically significant differences between different groups. The results showed that 63.8 per cent (62.6 per cent in Kinondoni and 66.0 per cent in Temeke) of the subjects had at least one type of anomaly, with a midline shift (22.5 per cent), spacing of at least 2 mm (21.9 per cent), and an open bite (16.1 per cent) being the most frequently recorded. The majority (93.6 per cent) of the children showed a Class I molar relationship. Class II and Class III malocclusions were registered in 4.4 and 2.0 per cent, respectively. Multiple logistic regression analyses, controlling for socio-demographic factors, showed that the odds ratio for having an open bite was 1.8 if residing in a less socio-economically privileged district. Subjects with decayed, missing, and filled teeth (DNFT) (>0) were 1.7, 2.1, 2.4, and 1.7, respectively, more likely to be diagnosed with a malocclusion, a midline shift, Angle Class II and III, and an open bite. Schoolchildren with fair/poor oral hygiene were less likely than their counterparts with good oral hygiene to be diagnosed with a midline shift. Malocclusions were prevalent in the Tanzanian children investigated and were associated with environmental factors in terms of caries experience and residing in a less affluent district. Preventive programmes to combat the prevalence of malocclusion are recommended.