Symmetry of palatal shape during the first year of life in healthy infants.

OBJECTIVES: The purpose of this study was to quantify the symmetry of the alveolar process of the maxilla and palate during the first year of life in healthy infants with the help of a semiautomatic segmentation technique. MATERIALS AND METHODS: Maxillary plaster models of seventy healthy babies at 0, 3, 6, 9, and 12 months were collected and digitized. A semiautomatic segmentation tool was used to extract the alveolus and palate. The resulting model was aligned within a reference frame and mirrored on its medial plane. Distance maps were created and analyzed to compare and quantify the differences between the two hemispheres. Additional hemispherical width and area measurements were performed. An ANOVA test with additional post hoc tests was performed to check if the symmetry changed during development. Finally, the results were tested on intra- and interobserver variability. RESULTS: The absolute mean inter-surface distance between the original and mirrored models in each age group ranged between 0.23 and 0.30 mm. Width and area analysis showed a small but significant larger left palatal hemisphere. ANOVA and post hoc tests showed no significant difference in symmetry between groups. Reliability analysis showed no significant differences between observers. CONCLUSIONS: This study showed that in this infant population, only a small degree of palatal asymmetry was present, which can be considered as normal and clinically irrelevant. CLINICAL RELEVANCE: The data from this study can be used in future comparative studies as reference data. Furthermore, modeling of these data can help in predicting the growth pattern, which may lead to improved treatment protocols for children with craniofacial anomalies.

[Activator or Herbst, what's best?] / Activator of Herbst; wat is beter?

In this article, the short- and long-term results of two types of functional appliances are discussed regarding their ability to stimulate the mandibular growth at mandibular retrognathia and reduce an increased overjet. Removable functional appliances, or activators, are compared to a fixed functional appliance, the Herbst appliance. The activator, often consisting of an acrylic base, is advised to be worn for 12 to 20 hours a day. The Herbst appliance consists of interconnected bands around the molar- and premolar bands, keeping the mandibula continuously positioned forward by means of hinges or telescopes. In the short-term, both appliances are effective in reducing the overjet, improving the molar-occlusion and reducing the mandibular retrognathia. The comparative literature is inconclusive as to which appliance is more effective on which level, skeletal or dentoalveolar. The removable appliances are more likely to be accepted at a younger age, whilst the fixed appliances are more suitable for the adolescents. The stability of the long-term treatment effects is minimally described in the existing literature. However, the highest stability rate seems to apply to the Herbst appliance. The impact of a widely applied second phase of treatment with fixed appliances, with possible use of intermaxillary class II elastics and retention using functional appliances is barely taken into account.

[Opinions on orthodontics: an online questionnaire among NTVT readers]. / Mening over orthodontie: een online enquête onder NTVT-lezers.

By means of an online questionnaire, the opinions of dental health practitioners on 'orthodontics' were assessed on the basis of 10 statements. There were 523 responses, 51% of which were from general practitioners, a relatively large number from orthodontists (31%) and 18% from other dental health practitioners. Concerning indication of treatment, dental health prior to treatment and the value of straightened teeth, opinions were clearly positive, somewhat more among orthodontist than among general practitioners. Patients knowledge concerning orthodontics and the negative side of orthodontics and their trust in the durability of orthodontic retention are all considered to be more positively present in patients by orthodontists than general practitioners. 1 in 3 non-orthodontists considered carrying out orthodontic procedures in the general practice to be fine. More than 90% of orthodontists disagreed. Female dental practitioners more often consider orthodontic treatment to belong with an orthodontist. The number of women was equally divided across the different groups.

Three dimensional maxillary growth modeling in newborns.

OBJECTIVES: The aim of this study was to develop an accurate and intuitive semi-automatic segmentation technique to calculate an average maxillary arch and palatal growth profile for healthy newborns in their first year of life. MATERIALS AND METHODS: Seventy babies born between 1985 and 1988 were included in this study. Each child had five impressions made in the first year after birth that were digitalized. A semi-automatic segmentation tool was developed and used to assess the maxillary dimensions. Finally, random effect models were built to describe the growth and build a simulation population of 10,000 newborns. The segmentation was tested for inter- and intra-observer variability. RESULTS: The Pearson correlation coefficient for each of the variables was between 0.94 and 1.00, indicating high inter-observer agreement. The paired sample t test showed that, except for the tuberosity distance, there were small, but significant differences in the landmark placements between observers. Intra-observer repeatability was high, with Pearson correlation coefficients ranging from 0.87 to 1.00 for all measurements, and the mean differences were not significant. A third or second degree growth curve could be successfully made for each parameter. CONCLUSIONS: These findings indicated this method could be used for objective clinical evaluation of maxillary growth. CLINICAL RELEVANCE: The resulting growth models can be used for growth studies in healthy newborns and for growth and treatment outcome studies in children with cleft lip and palate or other craniofacial anomalies.

[Orthodontic treatment of a malocclusion with a compromised central upper incisor]. / Orthodontische behandeling van een malocclusie met een gecompromitteerde centrale bovenincisief.

An 11-year-old girl presented at an orthodontist asking for the correction of the crooked position of her upper and lower front teeth. In addition, the patient was concerned about the abnormal shape and size of tooth 21. There was a disto-occlusion, crowding and tooth gemination of tooth 21 with the shape of a dens invaginatus. The tooth, moreover, was infected. Teeth 21 and 14 were extracted as part of the treatment. By means of a guided transposition, tooth 23 was brought to the extraction site of tooth 21. Treatment was performed with hybrid fixed appliance techniques.

The Asher-McDade Aesthetic Index in Comparison With Two Scoring Systems in Nonsyndromic Complete Unilateral Cleft Lip and Palate Patients.

OBJECTIVE: To compare the Asher-McDade aesthetic index with 2 systems used to score the appearance of the nasolabial area in patients with a complete cleft lip and palate. DESIGN: Retrospective analysis of the results of complete unilateral cleft lip and palate patients. SETTING: Academic Center for Dentistry of Amsterdam and the VU University Medical Center. PATIENTS: Six-year-olds with complete unilateral cleft lip and palate. MAIN OUTCOME MEASURES: Cleft lip and palate patients assessed using the scoring system proposed by Prahl et al, a 5-point ordinal scale, and the scoring system proposed by Asher-McDade et al by 6 judges, 3 orthodontists, and 3 plastic surgeons. A calculation of intra- and interobserver reliability was made. A comparison was made of all the assessment methods using Kendalls' tau. RESULTS: Photographs of 55 children (38 boys and 17 girls) with complete unilateral cleft lip and palate were assessed. For the scoring system of Prahl et al, interobserver reliability varied from 0.43 to 0.53, for the 5-point scale between 0.45 and 0.57, and for the scoring system by Asher-McDade et al these varied between 0.52 and 0.66. Multiple significant correlations were found between the used scoring systems. CONCLUSION: It can be concluded that the Asher-McDade aesthetic index is still superior to the other scoring systems used in this study. However, all 3 scoring systems can reliably be used when 3 or more observers are used.

Comparison of two scoring systems in the assessment of nasolabial appearance in cleft lip and palate patients.

OBJECTIVE: The aim of this study was to determine the reliability of 2 scoring systems. DESIGN: This study used a retrospective analysis of the results of complete unilateral cleft lip and palate patients. SETTING: The study was conducted at the VU Medical Center and the Academic Center for Dentistry of Amsterdam. PATIENTS: Patients were complete unilateral cleft lip and palate patients at the age of 6 years. MAIN OUTCOME MEASURES: Assessment of the nose and lip together and separately with a numerical photographic reference scoring system and with a 5-point ordinal scale without the use of a reference photograph by 6 judges. Intraobserver and interobserver reliability was calculated; both ways of assessment were compared by using Kendall tau. RESULTS: Photographs were available of 55 children (6 years old, 38 boys and 17 girls) with a complete unilateral cleft lip and palate. The interobserver reliabilities of the lip and nose together were 0.53 and, for the nose and lip separately, 0.51 and 0.43, respectively with the use of the numerical scale. In the 5-point scale, these were 0.55 for the nose and lip together and 0.57 and 0.45 for the nose and lip separately, respectively. Furthermore, it was found that the lip dominates in the scorings of the lip and nose together (linear regression analysis). CONCLUSIONS: The 2 tested systems are equivalent in their reliability and outcome. The lip is dominating in the overall scorings. It is advocated to use the 5-point scale without the use of a reference photograph and to assess the lip and nose separately.

The reliability and validity of the Index of Complexity, Outcome and Need for determining treatment need in Dutch orthodontic practice.

The Index of Complexity, Outcome and Need (ICON), based on international opinion, has been proposed as a multipurpose occlusal index. The aim of this study was to validate the ICON for treatment need in the Netherlands by relating it to Dutch orthodontic opinion. Furthermore, the reliability of this index was explored, for both a calibrated orthodontist and non-calibrated orthodontists. A sample of 102 patients was chosen which represented the actual distribution of severity of malocclusion experienced by orthodontists in every day practice. The ICON was scored, based on complete patients records of those 102 patients, by an examiner calibrated in the use of this index. The results were compared with the opinion about treatment need of seven Dutch orthodontists - the 'gold standard'. Nine non-calibrated orthodontists also scored the ICON for 49 patients. The intra-examiner agreement of both the non-calibrated and the calibrated orthodontists was moderate to high [0.52-0.86 and 0.89, respectively, measured with the Intraclass Correlation Coefficient (ICC)]. The inter-examiner agreement of the ICON score of the nine orthodontists was moderate measured with the single estimate of the ICC (0.60), and high measured with the average estimate (0.93). Spearman's correlation coefficient between the ICON score (calibrated) and the gold standard was sufficient: 0.78. The sensitivity and specificity were 1 and 0.36, respectively. The best compromise between sensitivity and specificity was at a cut-off point of 52, instead of the international ICON cut-off point of 43. There was a significant difference in ICON score between the non-calibrated orthodontists and the calibrated orthodontist, mainly based on the Aesthetic Component (AC) of the Index of Orthodontic Treatment Need (IOTN). It can be concluded that the ICON needs to be adjusted when used to determine treatment need in the Dutch orthodontic population.