The effect of increasing the gaps between the front teeth on torque and intrusion control of the incisors for anterior retraction with clear aligners: a prospective study.

OBJECTIVE: To investigate the effect of sequential distalization on increasing gaps in the maxillary anterior teeth, focusing on the control of torque and three-dimensional teeth movement during anterior retraction with clear aligners in extraction cases. METHODS: We recruited 24 patients who were undergoing extraction bilateral maxillary first premolars with clear aligners. According to a predetermined increment in the spaces between the maxillary anterior teeth, the patients were divided into three groups: those with no gap (9 cases), a 0.5 mm gap (6 cases) and a 1.0 mm gap (9 cases). In each group, a 2.0 mm en-mass retraction was applied on the anterior teeth. Plaster casts of the upper full dentition were obtained both before and after a 2 mm retraction. The palatal folds were used to overlap each pair of models. The three-dimensional movement of the teeth and the change of torque for the anterior teeth were subsequently analyzed using Geomagic Studio 2014 software. RESULTS: The change in torque in the groups with added gaps was significantly smaller than that in the group with no gaps (P < 0.05). There was no significant difference in this respect when comparing the group with a 0.5 mm gap added to the group with a 1.0 mm gap was added (P > 0.05). In the labial-lingual and vertical directions, the displacements of the central and lateral incisors were smaller in the groups with additional gaps compared to those in the groups without gaps (P < 0.05). However, there was no significant difference observed when comparing the group with a 0.5 mm added gap to the group with a 1.0 mm added gap (P > 0.05). Then, a comparison was made between the displacement of the second premolar to the second molar in the mesial-distal direction across all groups. The study revealed that the anchorage molars in the group without gaps demonstrated significantly smaller displacement compared to those in the group with additional gaps (P < 0.05). CONCLUSION: Advantages were observed in controlling the torque of the anterior teeth and achieving a desired pattern closer to normal bodily movement by sequentially distalizing the maxillary anterior teeth gaps. Increasing the gaps between the maxillary anterior teeth also resulted in improved control of the vertical direction of the anterior teeth. However, this retraction strategy necessitates substantial protection of the anchorage molars.

Prophylactic third molar removal: are oral surgeons and orthodontists aligned in preventive approaches?

BACKGROUND: There is a general consensus among dental professionals regarding the extraction of impacted third molars in the presence of clinical symptoms. However, there is less agreement on the management of asymptomatic third molars. The objective of this study is to compare the perspectives of oral surgeons and orthodontists regarding the indications for the extraction of asymptomatic third molars. It is possible that healthcare professionals from different specialties may approach the extraction of these teeth in different ways. METHODS: In this cross-sectional study, a web-based questionnaire has been employed to collect data by inquiring about the reasons why participants prefer the extraction of asymptomatic third molars. Descriptive statistics were employed to evaluate the data obtained. The level of significance was set at P < 0.05. RESULTS: Prophylactic extraction of partially impacted molars was more favored among the participants (P < 0.05). The orthodontists preferred prophylactic extraction due to the risk of late anterior dental crowding (LADC); however, the oral surgeons preferred pre-pregnancy extractions (P < 0.05). The extraction decision for partial impaction was higher in females when the risk of distal caries was considered. For fully impacted ones, it was higher in males when the risk of caries and pericoronitis were considered (P < 0.05). CONCLUSIONS: Orthodontists preferred extraction because of the risk of LADC and caries, while oral surgeons focused on preventing pericoronitis, pathology, focal infection, and symptoms during pregnancy. This divergence between the participants may inform the guidelines for prophylactic management of third molars. These findings may be pertinent in gender medicine. CLINICAL RELEVANCE: This study has been enlightening for departments to consult each other before the extraction of a patient's asymptomatic third molar.

Early prevention of maxillary canine impaction: a randomized clinical trial.

OBJECTIVES: To investigate the effect of three interceptive measures (slow maxillary expansion (SME) with removable plates (1), extraction of both upper deciduous canines (DC) (2) and no intervention (3)) on maxillary canine (MC) position in patients with early mixed dentition (EMD) and lack of upper arch space. These three groups were additionally compared to a control group (4) with adequate upper arch space. NULL HYPOTHESIS: None of the studied strategies outperforms the others regarding improvement of MC position. TRIAL DESIGN: Four-arm parallel group prospective randomized controlled trial. PARTICIPANTS: Patients in EMD with at least one impacted MC, non-resorbed DC, and no crossbite. INTERVENTIONS: Patients with a lack of space were randomly distributed to protocols (1), (2), and (3). PRIMARY OBJECTIVE: To assess the change in MC position after 18 months follow up. SECONDARY OBJECTIVES: To assess canine eruption and need for orthodontic intervention within 18-60 month follow up. OUTCOME ASSESSMENT: Five variables defined canine position: sector, canine-to-midline angle, canine-to-first-premolar angle, canine-cusp-to-midline distance, and canine-cusp-to-occlusal-plane distance on two panoramic radiographs at 0 (T1) and 18 months (T2). Mean differences between groups were compared with linear mixed models, corrected for age and sex. RANDOMIZATION: The patient allocation sequence was generated by an electronic randomization list. BLINDING: The operator taking the measurements was blinded to the groups. RESULTS: Seventy-six patients were included (142 canines, mean age 9.2 years, 60.5 per cent male, mean follow up 1.9 years), 19, 17, 14, and 26 patients in groups 1-4, respectively. In absence of dental crossbite in patients with lack of space and impacted MC, SME improved the canine sector (P = 0.040), compared to no intervention (P = 0.028). Canine-to-midline angle and canine-to-occlusal-plane distance significantly decreased in all groups at T2. Extraction improved the canine-to-first-premolar angle at T2 more than other strategies in EMD (P = 0.015-0.000). CONCLUSIONS: Early SME improves the canine sector and reduces the need for major orthodontic intervention in the long term. Taking a first panoramic radiograph in EMD allows timely intervention in case of MC impaction. TRIAL REGISTRATION NUMBER: NCT05629312 (Clinical Trials.org). Trial status: follow up ongoing.

Orthodontic Implementation of Machine Learning Algorithms for Predicting Some Linear Dental Arch Measurements and Preventing Anterior Segment Malocclusion: A Prospective Study.

Background and Objectives: Orthodontics is a field that has seen significant advancements in recent years, with technology playing a crucial role in improving diagnosis and treatment planning. The study aimed to implement artificial intelligence to predict the arch width as a preventive measure to avoid future crowding in growing patients or even in adult patients seeking orthodontic treatment as a tool for orthodontic diagnosis. Materials and Methods: Four hundred and fifty intraoral scan (IOS) images were selected from orthodontic patients seeking treatment in private orthodontic centers. Real inter-canine, inter-premolar, and inter-molar widths were measured digitally. Two of the main machine learning models were used: the Python programming language and machine learning algorithms, implementing the data on k-nearest neighbor and linear regression. Results: After the dataset had been implemented on the two ML algorithms, linear regression and k-nearest neighbor, the evaluation metric shows that KNN gives better prediction accuracy than LR does. The resulting accuracy was around 99%. Conclusions: it is possible to leverage machine learning to enhance orthodontic diagnosis and treatment planning by predicting linear dental arch measurements and preventing anterior segment malocclusion.

[Health relevance of malocclusions and their treatment]. / Zahn- und Kieferfehlstellungen ­ gesundheitliche Relevanz und Behandlung.

Malocclusions are among the most common human diseases impairing oral health. The present paper gives an overview on their etiology, prevalence, and consequences. It further presents the corrective and preventive potential of orthodontic treatment and gives information on the treatment-associated legal framework in Germany. The use and quality of the orthodontic health service will be described in the international context.The etiology of malocclusions has genetic, epigenetic, functional, and environmental components, which can seldomly be differentiated on the individual level. Previous small, cross-sectional studies show that up to 80% of children in Germany are affected. Eating, drinking, chewing, speaking, and breathing may be impaired and the predisposition for periodontal disease and overuse injuries of the temporomandibular joint and the masticatory musculature increase. A proclination of the upper incisors increases the risk for dental trauma. Furthermore, malocclusions may have negative psychosocial effects and impair quality of life. In cooperation with other dental and/or medical disciplines, orthodontics make positive preventive and curative contributions to oral health, general health, and quality of life.Against this background, orthodontics has a substantial potential for the enhancement of dental prevention in healthcare. This is especially true as the German social health insurance (GKV) allows for a widespread orthodontic treatment coverage of the population at an internationally accepted, high-quality level. To further improve prevention, the implementation of a systematic orthodontic screening at the age of 7-8 years in the form of a systematic preventive measure is recommended.

Non-nutritive sucking habits in a child: A clinical protocol to their prevention and management.

Patients presenting with anterior open bites can be challenging to manage. This paper discusses the clinical features and aetiology of anterior open bites caused by non-nutritive sucking habits in a young child. It explores how these should be recognised and how certain interventions can be effective in their management. Whilst further high quality research is needed into the different methods and their effectiveness, the aim of the article is to provide a practical guide for general dental practitioners, orthodontists and paediatric dentists, who are involved in monitoring the developing dentitions of these patients.

Factors associated with spontaneous angular changes of impacted mandibular third molars as a result of second molar protraction.

INTRODUCTION: This study aimed to identify significant factors affecting the spontaneous angular changes of impacted mandibular third molars as a result of second molar protraction. Temporary skeletal anchorage devices in the missing mandibular first molar (ML-6) or missing deciduous mandibular second molar (ML-E) with missing succedaneous premolar spaces provided traction. METHODS: Forty-one mandibular third molars of 34 patients (10 male and 24 female; mean age 18.3 ± 3.7 years) that erupted after second molar protraction were included in this study. They were classified into upright (U) and tilted (T) groups. Linear and angular measurements were performed at the time of treatment initiation (T1) and of ML-6 or ML-E space closure (T2). Regression analyses were used to identify significant factors related to third molar uprighting. RESULTS: Nolla stage (odds ratio [OR] 4.1), sex (OR 0.003 for male), third molar angulation at T1 (OR 1.1), missing tooth space (OR 0.006), rate of third molar eruption (OR 23.3), and rate of second molar protraction (OR 0.2) significantly affected third molar uprighting. Age, third molar angulation at T1, rate of third molar eruption, and rate of second molar protraction were significant factors for predicting third molar angulation at T2. CONCLUSIONS: Available space for third molar eruption before and after second molar protraction is not associated with uprighting of erupting third molars. Older patients whose third molars are in greater Nolla stage, are in a more upright position at T1, and have a greater eruption rate have a greater chance for third molar uprighting. Alternatively, an increase in second molar protraction rate results in mesial tipping of the third molars.

Clinical Success of Fiber-reinforced Composite Resin as a Space Maintainer.

INTRODUCTION: The early loss of deciduous molars is a frequently encountered problem in dentistry. Various space maintainer designs were developed to prevent the loss of the space. The aim of this study was to evaluate long-term clinical performance and survival rates of fiber-reinforced composite resin (FRCR) as a space maintainer clinically. MATERIALS AND METHODS: This study was designed on 44 children who had early missed deciduous molars. Space maintainers were prepared on plaster models of patients and fixed directly to the adjacent teeth. Survival rate and whether it causes any damage to adjacent teeth were examined clinically and radio-graphically for 24 months or until failure. Kaplan-Meier survival analysis was used for the statistical analyses. RESULTS: Overall, 16.2% of space maintainers were dislodged and accepted to be failed at the end of 12 months. At the 24-month control, 52.2% success was stated with the FRCR space maintainer and because of permanent tooth eruption, 31.8% of space maintainer were taken out. The mean duration of space maintainers was measured to be 14.8 ± 3.48 months. There was no statistical significance between survival time and gender, tooth number, localization, and measured space (p > 0.05). CONCLUSION: After all 24 months follow-up, as well as esthetic properties of FRCR space maintainer, their applicability in a single seance and strength against the forces are determined as the advantages of the technique. CLINICAL SIGNIFICANCE: The FRCR space maintainers can be thought of as alternatives to metal space maintainers.

Malocclusion in the primary dentition in children with and without deformational plagiocephaly.

OBJECTIVES: Asymmetries of the jaw and orthodontic abnormalities are suspected as long-term consequences of positional cranial deformity. But only few data exist on this issue. As plagiocephaly is a common problem in infancy, potential functional impairments should be investigated to initiate appropriate measures if necessary. The aim of our study was to compare the orthodontic situation in primary dentition of children with positional plagiocephaly and children without cranial deformities. MATERIAL AND METHODS: Fifty children treated by helmet therapy for plagiocephaly and 50 non-affected children (age 1.98-5.69 years) were examined in a cross-sectional study. Orthodontic parameters of all dimensions were assessed and analyzed. RESULTS: Children of the plagiocephalic group showed more often orthodontic alterations compared to the others. Especially the frequencies of a class II malocclusion (36 vs. 14 %), an edge-to edge bite (28 vs. 12 %), and deviations of the midline (38 vs. 16 %) were conspicuous. However, none of the differences was significant (p > 0.003). Of all observed mandibular asymmetries, 69 % appeared as a shift to the contralateral side of the former flattened occipital region. CONCLUSION: Positional head deformity might be associated in some cases with a higher prevalence of occlusal abnormalities in primary dentition. CLINICAL RELEVANCE: Positional plagiocephaly interfaces medicine and dentistry. As it is a common disorder, this etiology has to be considered in the prevention and therapy of malocclusion.

Orthodontic retention to have and to hold.

Data sourcesCochrane Oral Health Group's Trials Register, Cochrane Central Register of Controlled Trials (CENTRAL), Medline, Embase, US National Institutes of Health Trials Registry and The World Health Organization (WHO) Clinical Trials Registry Platform, abstracts from the British Orthodontic Conference, the European Orthodontic Conference and the International Association for Dental Research (IADR) from 2011 to 2015 and the bibliographies of identified studies.Study selectionRandomised controlled trials (RCTs) involving children and adults who had had retainers fitted or adjunctive procedures undertaken to prevent relapse following orthodontic treatment with braces were considered.Data extraction and synthesisTwo reviewers independently selected studies, abstracted data and assessed study quality. For continuous data mean differences (MD) with 95% confidence intervals (CI) were calculated with ratios (RR) and 95% CI for dichotomous outcomes.ResultsFifteen studies involving a total of 1722 patients were included. Seven studies were considered to be at high risk of bias, four at low risk and four at unclear risk. For removable retainers versus fixed retainers (three studies) there was low quality evidence that thermoplastic removable retainers provided slightly poorer stability in the lower arch than multistrand fixed retainers: MD (Little's Irregularity Index, 0 mm is stable) 0.6 mm (95% CI 0.17 to 1.03) and of less gingival bleeding with removable retainers: RR 0.53 (95%CI; 0.31 to 0.88). Patients found fixed retainers more acceptable to wear, with a mean difference on a visual analogue scale (VAS; 0 to 100; 100 being very satisfied) of -12.84 (95% CI -7.09 to -18.60).For different types of fixed retainers (four studies) data from three studies (228 patients) comparing polyethylene ribbon bonded retainer versus multistrand retainer were pooled showing no evidence of a difference in failure rates. RR = 1.10 (95%CI; 0.77 to 1.57).Pooled data from two trials (174 patients) comparing the same types of upper fixed retainers, showed a similar finding: RR =1.25 (95%CI; 0.87 to 1.78).For different types of removable retainers (eight studies) one study at low risk of bias comparing upper and lower part-time thermoplastic versus full-time thermoplastic retainers showed no evidence of a difference in relapse (graded moderate quality evidence). Another study, comparing part-time and full-time wear of lower Hawley retainers, found no evidence of any difference in relapse (low quality evidence). Two studies at high risk of bias suggested that stability was better in the lower arch for thermoplastic retainers versus Hawley, and for thermoplastic full-time versus Begg (fulltime) (both low quality evidence). In one study, participants wearing Hawley retainers reported more embarrassment more often than participants wearing thermoplastic retainers: RR 2.42 (95% CI 1.30 to 4.49; one trial, 348 participants, high risk of bias, low quality evidence). They also found Hawley retainers harder to wear. There was conflicting evidence about survival rates of Hawley and thermoplastic retainers.For combination of upper thermoplastic and lower bonded versus upper thermoplastic with lower adjunctive procedures versus positioner (one study) there was no evidence of a difference in relapse between the combination of an upper thermoplastic and lower canine to canine bonded retainer and the combination of an upper thermoplastic retainer and lower interproximal stripping, without a lower retainer. Both these approaches are better than using a positioner as a retainer.ConclusionsWe did not find any evidence that wearing thermoplastic retainers fulltime provides greater stability than wearing them part-time, but this was assessed in only a small number of participants. Overall, there is insufficient high quality evidence to make recommendations on retention procedures for stabilising tooth position after treatment with orthodontic braces. Further high quality RCTs are needed.

Interventions for the cessation of non-nutritive sucking habits in children.

BACKGROUND: Comforting behaviours, such as the use of pacifiers (dummies, soothers), blankets and finger or thumb sucking, are common in babies and young children. These comforting habits, which can be referred to collectively as 'non-nutritive sucking habits' (NNSHs), tend to stop as children get older, under their own impetus or with support from parents and carers. However, if the habit continues whilst the permanent dentition is becoming established, it can contribute to, or cause, development of a malocclusion (abnormal bite). A diverse variety of approaches has been used to help children with stopping a NNSH. These include advice, removal of the comforting object, fitting an orthodontic appliance to interfere with the habit, application of an aversive taste to the digit or behaviour modification techniques. Some of these interventions are easier to apply than others and less disturbing for the child and their parent; some are more applicable to a particular type of habit.  OBJECTIVES: The primary objective of the review was to evaluate the effects of different interventions for cessation of NNSHs in children. The secondary objectives were to determine which interventions work most quickly and are the most effective in terms of child and parent- or carer-centred outcomes of least discomfort and psychological distress from the intervention, as well as the dental measures of malocclusion (reduction in anterior open bite, overjet and correction of posterior crossbite) and cost-effectiveness. SEARCH METHODS: We searched the following electronic databases: the Cochrane Oral Health Group Trials Register (to 8 October 2014), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2014, Issue 9), MEDLINE via OVID (1946 to 8 October 2014), EMBASE via OVID (1980 to 8 October 2014), PsycINFO via OVID (1980 to 8 October 2014) and CINAHL via EBSCO (1937 to 8 October 2014), the US National Institutes of Health Trials Register (Clinical Trials.gov) (to 8 October 2014) and the WHO International Clinical Trials Registry Platform (to 8 October 2014). There were no restrictions regarding language or date of publication in the searches of the electronic databases. We screened reference lists from relevant articles and contacted authors of eligible studies for further information where necessary. SELECTION CRITERIA: Randomised or quasi-randomised controlled trials in children with a non-nutritive sucking habit that compared one intervention with another intervention or a no-intervention control group. The primary outcome of interest was cessation of the habit. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by The Cochrane Collaboration. Three review authors were involved in screening the records identified; two undertook data extraction, two assessed risk of bias and two assessed overall quality of the evidence base. Most of the data could not be combined and only one meta-analysis could be carried out. MAIN RESULTS: We included six trials, which recruited 252 children (aged two and a half to 18 years), but presented follow-up data on only 246 children. Digit sucking was the only NNSH assessed in the studies. Five studies compared single or multiple interventions with a no-intervention or waiting list control group and one study made a head-to-head comparison. All the studies were at high risk of bias due to major limitations in methodology and reporting. There were small numbers of participants in the studies (20 to 38 participants per study) and follow-up times ranged from one to 36 months. Short-term outcomes were observed under one year post intervention and long-term outcomes were observed at one year or more post intervention. Orthodontics appliance (with or without psychological intervention) versus no treatmentTwo trials that assessed this comparison evaluated our primary outcome of cessation of habit. One of the trials evaluated palatal crib and one used a mix of palatal cribs and arches. Both trials were at high risk of bias. The orthodontic appliance was more likely to stop digit sucking than no treatment, whether it was used over the short term (risk ratio (RR) 6.53, 95% confidence interval (CI) 1.67 to 25.53; two trials, 70 participants) or long term (RR 5.81, 95% CI 1.49 to 22.66; one trial, 37 participants) or used in combination with a psychological intervention (RR 6.36, 95% CI 0.97 to 41.96; one trial, 32 participants). Psychological intervention versus no treatmentTwo trials (78 participants) at high risk of bias evaluated positive reinforcement (alone or in combination with gaining the child's co-operation) or negative reinforcement compared with no treatment. Pooling of data showed a statistically significant difference in favour of the psychological interventions in the short term (RR 6.16, 95% CI 1.18 to 32.10; I(2) = 0%). One study, with data from 57 participants, reported on the long-term effect of positive and negative reinforcement on sucking cessation and found a statistically significant difference in favour of the psychological interventions (RR 6.25, 95% CI 1.65 to 23.65). Head-to-head comparisonsOnly one trial demonstrated a clear difference in effectiveness between different active interventions. This trial, which had only 22 participants, found a higher likelihood of cessation of habit with palatal crib than palatal arch (RR 0.13, 95% CI 0.03 to 0.59). AUTHORS' CONCLUSIONS: This review found low quality evidence that orthodontic appliances (palatal arch and palatal crib) and psychological interventions (including positive and negative reinforcement) are effective at improving sucking cessation in children. There is very low quality evidence that palatal crib is more effective than palatal arch. This review has highlighted the need for high quality trials evaluating interventions to stop non-nutritive sucking habits to be conducted and the need for a consolidated, standardised approach to reporting outcomes in these trials.

Completion of nonreducible Le Fort fractures by Le Fort I osteotomy: sometimes an inevitable choice to avoid postoperative malocclusion.

The aim of this study was to prospectively evaluate the use of a simultaneous Le Fort I osteotomy for completion of nonreducible Le Fort fractures. We analyzed the clinical and radiological data of 44 patients with Le Fort fractures, 9 of whom presented with a nonreducible type. Seven patients with an incomplete Le Fort I fracture had a contralateral Le Fort I osteotomy, and 2 patients with an incomplete Le Fort III fracture had a true bilateral Le Fort I-type osteotomy. We recorded age and sex, mechanism of injury, level of Le Fort fracture, concomitant mandibular fractures, concomitant maxillomandibular fixation (MMF) and its duration, surgical approach, status of healing, and complications. Follow-ups were at 1 week and 1, 3, 6, and 12 months.All patients recovered their normal pretrauma occlusion without the need for postoperative elastic guidance, except for 1 patient who required light class III traction elastics for 3 weeks to achieve the correct occlusion. None of the patients presented with intraoperative or postoperative complications.The present study has demonstrated that completion of nonreducible Le Fort fractures by Le Fort I osteotomy results in a high rate of success.

Preventive treatment of post-traumatic dental infraocclusion: study on the knowledge of dental decoronation in a sample of Italian dental students and dentists.

AIM: The aim of the present work is to investigate whether dental decoronation is a procedure known by a sample of dental students and Italian dentists. Dental decoronation technique is performed in order to mitigate the outcomes which may occur after a delayed tooth replantation. MATERIALS AND METHODS: A cognitive survey about the knowledge of the dental decoronation technique was carried on two groups: a sample of 120 dental students (5th year of dental school), from University of Cagliari, Sassari and of Chieti-Pescara (60 males and 60 females), and a group which involved 200 Italian dentists (age comprised between 25 and 45, 130 females and 70 males) enrolled at pedodontics and orthodontics Masters and CE courses (University of Roma Sapienza, Chieti- Pescara, Cagliari). The latter group's main field of work was paediatric dentistry and orthodontics, two dental specialties often involved in treating Traumatic dental injuries. RESULTS: Only 20 dentists out of the 200 interviewed answered that they knew this technique and only 5 of them proved to know it and were able to describe it correctly. No students interviewed knew this technique. CONCLUSION: It is apparent from the results of this survey that there is very little information about the dental decoronation technique both during the Degree Course in Dentistry and Post Graduate specialty programmes (Continuing Education Courses and Masters).

The efficacy of Italian guidelines in promoting oral health in children and adolescents.

AIM: The purpose of the study was to evaluate the efficacy of the guidelines on oral health published by the Italian Health Ministry. STUDY DESIGN: 1239 patients (582 girls and 657 boys) with a mean age of 4.46 (SD 2.81) years were evaluated before application of the guidelines by paediatricians (T0) for the presence of caries, gingivitis, diseases of the oral mucosa, and malocclusion. Only patients aged 6 months, 3 years, 6 years, and 9 years at T0 were taken into consideration. All patients were reevaluated after application of the ministerial guidelines (T1). METHODS: the study took place over a 3-year period. Enrolled patients referred to the outpatient clinics of three paediatricians of the Province of Genoa who strictly applied the ministerial guidelines. STATISTICS: Chi square test analysis was performed to evaluate a statistically significant decrease in the incidence of caries, gingivitis and diseases of the oral mucosa. RESULTS: After a 3-year follow-up collected data underlined a statistically significant decrease in the incidence of dental caries, gingivitis and oral mucosal diseases after implementation of the recommended ministerial guidelines. A statistically significant decrease of malocclusions was also evident in the elder patients (12 years old at T1). CONCLUSION: The accurate implementation of the Guidelines is supported. Only collaboration and increased synergy between paedodontists and paediatricians can fulfill the objectives which were the reason for publishing the "National guidelines for the promotion of oral health and the prevention of oral diseases in developmental age".

[Recognizing and preventing disturbances in eruption]. / Herkennen en voorkomen van eruptiestoornissen.

Disturbances in eruption and related problems are quite common in permanent dentition but rare in deciduous dentition. For the timely recognition of disturbances in eruption, knowledge of the normal development of dentition is essential. Disturbances in eruption comprise disturbances in which eruption does not occur at all, in which it is delayed or incomplete, or in which the normal direction of eruption is influenced. If identified early enough, many undesirable dental conditions can be avoided or their seriousness can be limited. A possible impacting of permanent cuspids, for example, can be avoided by extracting the deciduous cuspids at the right moment; in cases of a large overjet or the threat of a cover-bite, lip interference can be prevented.

Friction forces during sliding of various brackets for malaligned teeth: an in vitro study.

AIMS: To measure the friction force generated during sliding mechanics with conventional, self-ligating (Damon 3 mx, Smart Clip, and Time 3) and low-friction (Synergy) brackets using different archwire diameters and ligating systems in the presence of apical and buccal malalignments of the canine. METHODS: An experimental setup reproducing the right buccal segment of the maxillary arch was designed to measure the friction force generated at the bracket/wire and wire/ligature interfaces of different brackets. A complete factorial plan was drawn up and a three-way analysis of variance (ANOVA) was carried out to investigate whether the following factors affect the values of friction force: (i) degree of malalignment, (ii) diameter of the orthodontic wire, and (iii) bracket/ligature combination. Tukey post hoc test was also conducted to evaluate any statistically significant differences between the bracket/ligature combinations analyzed. RESULTS: ANOVA showed that all the above factors affect the friction force values. The friction force released during sliding mechanics with conventional brackets is about 5-6times higher than that released with the other investigated brackets. A quasilinear increase of the frictional forces was observed for increasing amounts of apical and buccal malalignments. CONCLUSION: The Synergy bracket with silicone ligature placed around the inner tie-wings appears to yield the best performance.

Case history: improved maxillary growth and development following digit sucking elimination and orofacial myofunctional therapy.

Orofacial myologists are frequently called upon to address retained oral habit concerns. During this process, current I.A.O.M. recommended treatment includes addressing tongue, lip, and jaw rest posture concerns. Following digit sucking remediation, we may also be called upon to address these rest posture issues, and tongue thrust more aggressively together. In this process, facial growth and development and jaw structure may coincidentally improve as a result of 'nature taking its course' by addressing both swallow AND rest posture. In a select subset of clients, dramatic improvements may occur if the timing is right. This article discusses one such case that appears to have yielded a significant improvement in oral postures influencing improved facial and oral growth and development.

A Scottish cost analysis of interceptive orthodontics for thumb sucking habits.

OBJECTIVE: There is a potential cost saving to be made within the NHS by providing simple interceptive treatment rather than comprehensive treatment at a later date. The focus of this study is to determine the size of this potential cost by looking at the cost to NHS Tayside for the provision of interceptive treatment for cessation of thumb sucking and where this has been unsuccessful (or not provided) the costs of correction of the associated malocclusion. DESIGN: A cost analysis is described, investigating the costs of treatment solely to the NHS, both in the primary and secondary setting. METHODS: Three potential treatment pathways are identified with the costs calculated for each pathway. The actual cost of providing this treatment in NHS Tayside, and the potential cost saving in Tayside if there was a change in clinical practice are calculated. Both discounting of costs and a sensitivity analysis are performed. RESULTS: The cost to NHS Tayside of current practice was calculated to be between £123,710 and £124,930 per annum. Change in practice to replace use of a removable with a fixed habit breaker for the interceptive treatment of thumb sucking reduced the calculated cost to between £99,581 and £105,017. CONCLUSION: A saving could be made to the NHS, both locally and nationally, if the provision of a removable habit breaker was changed to a fixed habit breaker. In addition, increasing the proportion receiving active treatment, in the form of a fixed habit breaker, rather than monitoring, would appear to further reduce the cost to the NHS considerably.

Removable orthodontic appliances: new perspectives on capabilities and efficiency.

AIM: Removable appliances are a dependable choice for many patients but like all orthodontic appliances, they have some limitations in use. Patient selection and appropriate appliance design are two key factors for success. Many patients, especially adults, prefer intra-oral appliances to extra-oral devices. Sometimes a removable intra-oral appliance can solve a dental problem in a shorter period of time compared to fixed treatment, and this has also been repeatedly seen in molar distalisation. From the interceptive perspective, the appliance can prevent or alleviate an impending crowding for erupting permanent incisors. CASE REPORT: This article describes 5 patients with different orthodontic problems: impending crowding for erupting upper canine with 2 approaches, provision of space for upper cuspids, resolution of chronic attrition of anterior teeth, relief of space shortage for upper canines eruption, and reduction of excess overjet. All subjects were treated with removable appliances of various designs.