The effect of tooth borne versus skeletally anchored Alt-RAMEC protocol in early treatment of Class III malocclusion: a single-centre randomized clinical trial.

TRIAL DESIGN: This was a randomized, controlled trial designed to compare outcomes between the use of dental and skeletal anchorage, using the Face mask/Alternate Rapid Maxillary Expansion and Contraction (FM/Alt-RAMEC) protocol. METHODS AND PARTICIPANTS: The study was carried out at Mater Dei Hospital, Malta and included prepubertal skeletal Class III malocclusion patients where the aetiology was primarily maxillary hypoplasia. INTERVENTIONS: Two groups were assigned. Group I was treated with FM/Alt-RAMEC and group II was treated with skeletally anchored FM/Alt-RAMEC. Wear-time (WT) of the FM was monitored using TheraMon microsensors. Patients were instructed to wear the FM for 12-14 hours/day for 9 months. Changes were evaluated with lateral cephalograms and analysed with Wilcoxon and Mann-Whitney U tests. ANOVA was used to analyse the effect of gender on compliance parameters. Spearman's correlation coefficient was used to assess the correlation between compliance and skeletal changes. OBJECTIVE: To compare the skeletal and dentoalveolar changes in patients treated with these two protocols. OUTCOMES: The primary outcome was to assess skeletal and dentoalveolar outcomes in patients treated with skeletally anchored FM/RME and tooth-borne FM/RME; utilizing Alt-RAMEC protocol. The secondary outcome was compliance rate and adherence to FM wear among patients. RANDOMIZATION: Randomizer software and the sealed envelope technique were used to randomly allocate patients 1:1 into either group I (tooth-borne FM/Alt-RAMEC) or group II (skeletally anchored FM/Alt-RAMEC). BLINDING: It was not possible to blind to treatment allocation, but blinding was used when assessing the outcomes. RESULTS: Numbers randomized and analysed. Thirty-five patients were allocated. Group I consisted of 18 subjects and group II consisted of 17 subjects. One patient in group I dropped out due to illness, so 17 subjects in each group completed the study. OUTCOMES: Post-treatment changes in group I showed significant increases in SNA (2.10°), ANB (3.90°), Wits (4.70 mm), and overjet (5.40 mm). Group II showed significant increases in ANB (3.10°), Wits (3.20 mm), and overjet (4.50 mm). Wearing time for group I patients was 7.87 ± 2.88 hours/day and for group II was 6.98 ± 2.68 hours/day, with no significant difference between the groups. LIMITATIONS: Lack of long-term follow-up post-treatment, making the conclusion applicable only in the short term. HARMS: No harm was observed in both groups. CONCLUSION: Despite the large difference between the measured and the patient-reported daily WT, both tooth-borne and skeletally anchored FM/Alt-RAMEC showed positive, similar, skeletal and dental effects. CLINICAL TRIAL REGISTRATION: ISRCTN12197405.

Questions of logic in Atlas methods of dental age estimation.

PURPOSE: To review aspects of the underlying methodological procedures in Atlas Methods of Dental Age Estimation (DAE) research publications. Attention is paid to issues of Reference Data supporting the Atlases, details of analytic procedures in the development of the Atlases, the statistical reporting of results of Age Estimation (AE), the problems of expressing uncertainty, and the viability of conclusions in the reporting of DAE studies. METHODS: Research reports utilizing Dental Panoramic Tomographs for creating Reference Data Sets (RDS) were studied to unravel the processes of creating Atlases with a view to determining the appropriate procedures for developing numerical RDS and compiling them into an Atlas format to enable DAE of child subjects without birth records. RESULTS: The five different Atlases reviewed gave several different results in terms of AE. The possible causes of this were discussed - namely inadequate representation of Reference Data (RD) and lack of clarity in expressing uncertainty. It is suggested that the method of compiling Atlases needs to be more clearly defined. The yearly intervals described by some of the Atlases fails to take account of the Uncertainty of Estimates which is usually slightly greater than ±2½ years. CONCLUSION: The review of published Atlas design papers in the field of DAE shows a number of different study designs, statistical procedures, and presentational styles, particularly with regard to the statistical procedures and findings. These show that Atlas methods can only be accurate to what amounts to at best a year. RECOMMENDATIONS: Atlas methods lack the accuracy and precision of other methods of AE an example of which is the Simple Average Method (SAM).1 This inherent lack of accuracy must be taken into account when using Atlas methods for AE.

Root canal width as a mandibular maturity marker at the 18-year threshold in the Maltese population.

INTRODUCTION: The determination of age of majority (the 18-year-old threshold) using the popular Demirjian tooth staging method is unreliable, so other maturity markers are required. This study examines whether the ratio of the root canal widths (RCW) of the mandibular first, second and third molars is a useful indicator of age. METHODS: Nine hundred eighteen dental panoramic radiographs (DPT) were examined and the ratio of the mid-points of the distal roots of the left mandibular first, second and third molars assessed according to the RCW stages as described by Roberts (J Forensic Sci 62:351-354, 2017). RESULTS: Individuals who had reached stages RCW-A and RCW-B were represented in a wide range of ages spanning the 18-year-old threshold. Individuals who had reached Stage RCW-C were all above the 18-year-old threshold. It was not possible to analyse a large number of DPTs for various reasons. DISCUSSION: Individuals categorised as stage RCW-C may be deemed to have reached the 18-year-old threshold. These results are consistent with other published studies. Variation in root morphology and in the rate of development of the third molar limits the applicability of this method. CONCLUSIONS: RCW staging is an accurate method of determining the 18-year-old threshold. Its limited applicability requires the use of substitute markers in a large number of cases.

Canine exposure: open or closed?

Evidence for open or closed exposure of palatally displaced canines is equivocal, but this study sheds light on new facets which may influence the method of choice. The aim of this article is to give a short perspective on this field, highlight the merits of a study published in this issue of the European Journal of Orthodontics by Björksved et al. the study, place the findings into context and show how it may influence clinical practice.

Dental age estimation of young subjects with unilateral palatally displaced canine teeth.

INTRODUCTION: Delayed tooth eruption is often seen in patients with palatally displaced canines (PDC), but there is controversy over whether tooth formation is also delayed. This study attempts to elucidate the answer by addressing methodological shortcomings in previous studies. METHODS: Archived records were searched, and 100 patients (aged 8-16 years) with unilateral PDC were identified. Records of 50 women and 50 men were matched for age and sex with unaffected controls. The exclusion criteria included hypodontia. Dental age (DA) was calculated using the population-specific Maltese database and subtracted from the chronological age (CA). Nonparametric tests were used to compare CA-DA in patients with PDC and controls to determine the DA of end-of-series teeth. RESULTS: No statistically significant difference with CA-DA between patients with PDC and controls was found. In addition, there were no particular teeth significantly delayed in development. CONCLUSIONS: Unilateral PDC does not affect dental developmental age, and the end-of-series teeth investigated show no delay in development.

Root Pulp Visibility as a mandibular maturity marker at the 18-year threshold in the Maltese population.

INTRODUCTION: The determination of age of majority (the 18-year-old threshold) using the popular Demirjian tooth staging method is unreliable, so other maturity markers are required. This study examines whether the Root Pulp Visibility (RPV) of the mandibular third molar is a useful indicator of age. METHODS: One thousand six dental panoramic radiographs (DPTs) were examined and the left mandibular third molar assessed according to the RPV stages using the method of Olze et al. (Int J Legal Med 124:183-186, 2010) as modified by Lucas et al. (Forensic Sci Int 270:98-102, 2017). Six hundred sixty-two DPTs, 288 males and 374 females, satisfied the inclusion criteria. RESULTS: Individuals who had reached stages RPV-A and RPV-B were represented in a wide range of ages spanning the 18-year-old threshold. Individuals who had reached stages RPV-C and RPV-D were all above the 18-year-old threshold. It was not possible to analyse a large number of DPTs for various reasons. DISCUSSION: Individuals whose mandibular third molar exhibited stages RPV-C and RPV-D may be deemed to have reached the age of majority. These results are consistent with other published studies. Variation in the rate of development of the third molar limits the applicability of this method. CONCLUSIONS: RPV staging is an accurate method of determining the 18-year-old threshold. Substitute methods are required in a large number of cases.

A novel PAX9 mutation causing oligodontia.

INTRODUCTION: An extended family presenting with several members affected by developmentally missing teeth was investigated by analysis of the MSX1 and PAX9 genes. MATERIALS AND METHODS: Saliva samples were collected and DNA extracted. Primers were designed to span the exons and intron-exon junctions of the MSX1 and PAX9 genes. These primers were optimised using gradient Polymerase Chain Reaction. The amplified fragments were sent for Sanger sequencing RESULTS: a novel heterozygote missense mutation in exon 3 of PAX9 (c.296G > C, p.A99P), was found in two severely affected members of the family as well as a potentially pathogenic heterozygote variant (c.119C > G, p.A40G) in exon 1 of the MSX1 gene. CONCLUSION: The PAX9 A99P mutation is in the DNA binding domain and is predicted to be pathogenic.

Dental age estimation of children and adolescents: Validation of the Maltese Reference Data Set.

The purpose of this study was to validate a Reference Data Set, developed from the radiographic archives of the Dental Department, Mater Dei Hospital, Malta, for Dental Age Estimation of the Maltese population and to assess the accuracy of the method. Dental Panoramic Tomograms of 100 male and 100 females were selected. Tooth Development Stages were recorded for all 16 permanent teeth on the left and both third molars on the right. Summary and percentile data were calculated for each Tooth Development Stage and the Dental Age of each subject estimated using the unweighted average method. The distribution of the differences between the Dental and Chronological age was analysed. There was no statistically significant difference between the means of the Dental and Chronological ages and the mean differences were within acceptable limits. The conclusion was that the Dataset is valid for the Maltese population and the method used gives adequate accuracy.

Dental age assessment of Maltese children and adolescents. Development of a reference dataset and comparison with a United Kingdom Caucasian reference dataset.

The purpose of this study was to develop and validate a Reference Data Set for Dental Age Assessment of the Maltese population and compare the mean Age of Attainment to a UK Caucasian Reference Data Set. The Maltese Reference Data Set was developed from 1593 Dental Panoramic Tomograms of patients aged between 4 and 26 years, taken from the radiographic archives of the Dental Department, Mater Dei Hospital, Malta. Tooth Development Stages were recorded for all 16 maxillary and mandibular permanent teeth on the left side and both permanent third molars on the right, according to Demirjian's staging method. Summary and percentile data were calculated for each Tooth Development Stage, including the mean Age of Attainment. These means were used to estimate the Dental Age of each subject in the study sample using the simple unweighted average method. The estimated Dental Age was compared to the gold standard of the Chronological Age. Comparison of the Maltese and UK Caucasian Reference Data Set was by a series of t-tests, carried out for each paired Tooth Development Stage by gender. The mean Age of Attainment was slightly higher for the Maltese than the UK Caucasians in both males and females. However there was no statistically significant difference between the Chronological Age and Dental Age for either sex.

Comparison of the dental anomalies found in maxillary canine-first premolar transposition cases with those in palatally displaced canine cases.

AIM: To compare the developmental dental anomalies associated with maxillary canine-first premolar (MxCP1) transposition and those of palatally displaced canine (PDC) with each other and with the background prevalence in the Maltese population in order to elucidate whether the two conditions have similar or differing genetic backgrounds. MATERIALS AND METHODS: Dental records of 477 subjects with PDC, 57 subjects with MxCP1, and a control group of 500 subjects with no history of a PDC or tooth transposition were compared for canine eruption anomalies and hypodontia. RESULTS: A high frequency of bilateral occurrence was present for both canine malpositions and when unilateral, a trend to right-sided occurrence was evident. The occurrence of transpositions in the PDC group and of PDC in the MxCP1 group was higher than expected. The prevalence of incisor hypodontia was significantly higher in subjects with PDC and MxCP1, as compared to the control group. LIMITATIONS: The size of the MxCP1 group is relatively small. The study population is a small isolated Caucasian population and the results may not be applicable to other populations. CONCLUSIONS: There is no significant difference between the MxCP1 and PDC groups in the prevalence or distribution of hypodontia and each of these groups exhibits a higher prevalence of the other canine anomaly. These findings support the theory that PDC and MxCP1 form part of a group of interrelated dental anomalies that share a common genetic basis.

Dental anomalies in first-degree relatives of transposed canine probands.

The aim of this study was to investigate and compare the inheritance pattern and prevalence of inheritable dental anomalies in a sample of patients with maxillary canine-first premolar transposition and their first-degree relatives with a sample of palatally displaced canine families. Thirty-five consecutive maxillary canine-first premolar transposition probands and 111 first-degree relatives were matched to 35 consecutive palatally displaced canine probands and 115 first-degree relatives. These were assessed for palatally displaced canines and incisor-premolar hypodontia. Parental age at birth of the proband was also noted. The results revealed that (i) there is no difference in the overall prevalence of palatally displaced canine or incisor-premolar hypodontia between the groups of relatives; (ii) first-degree relatives of bilateral palatally displaced canine probands have a higher prevalence of palatally displaced canine and incisor-premolar hypodontia than those with unilateral palatally displaced canine; and (iii) maternal age at birth of the maxillary canine-first premolar transposition probands was significantly higher than that of the palatally displaced canine probands. The results suggest that maxillary canine-first premolar transposition and palatally displaced canine are unlikely to be different genetic entities and also indicate environmental or epigenetic influences on dental development.

The effect of NitrAdine on the Candida levels of maxillary removable appliances.

OBJECTIVE: Candida colonization is a consequence of orthodontic treatment and can lead to oral candidosis as a complication of maxillary removable appliance treatment. During orthodontic treatment, it is important to minimize colonization to prevent active infection that could consequently interfere with treatment. Hygiene is the most important factor in managing colonization; in this study, the efficacy of NitrAdine to reduce Candida was tested. METHOD AND MATERIALS: A randomized, double-blind, placebo-controlled trial was performed. Ninety-two patients 11 to 14 years of age were recruited at the Children's and the University Dental Clinics at Mater Dei Hospital, Tal-Qroqq, Msida, Malta. Forty-four patients used the product with NitrAdine, while 48 patients used a placebo. Sampling employing the imprint technique was performed before and after the product was used. Brilliance Candida agar was used for cultures and identification. Further identification was performed using Auxacolor 2 when required. RESULTS: The control group had a statistically significant increase in Candida during treatment, while the experimental group had a nonstatistically significant decrease. CONCLUSION: It was concluded that NitrAdine may reduce the Candida burden in maxillary removable appliances. Larger sample sizes are needed to achieve statistical significance.

Randomized, double-blind, placebo-controlled trial to test the efficacy of nitradine tablets in maxillary removable orthodontic appliance patients.

OBJECTIVE: to evaluate the efficiency of NitrAdine (MSI Laboratories) tablets in the reduction of oral Candida levels, biofilm formation, and appliance odor in maxillary removable orthodontic appliance wearers. METHOD AND MATERIALS: seventy children between 11 and 15 years of age undergoing maxillary removable appliance treatment were assigned via a double-blind randomized method to the experimental or placebo arm of the study. One milliliter of unstimulated saliva was collected at the beginning of the experiment and 6 weeks later after treatment of the maxillary removable appliance with NitrAdine tablets. Samples were cultured on chromogenic Candida agar, and the number of colony-forming units per mL of saliva (CFU mL-1) was determined. RESULTS: there was no significant difference in salivary Candida levels before or after treatment with NitrAdine tablets. There was a significant drop in plaque accumulation on the appliance and a significant amelioration in appliance odor. There was a small, nonsignificant drop in individuals exhibiting counts of 400 CFU mL-1 or more in the experimental group and a nonsignificant increase in the number of new species in the placebo group. CONCLUSIONS: NitrAdine tablets are effective in reducing plaque accumulation and appliance odor during maxillary removable appliance treatment. Further in vivo studies are required to determine the efficacy and exact protocol for NitrAdine tablets in appliance disinfection.

Morphologic and developmental disturbances of permanent teeth following trauma to primary dentition in a selected group of Maltese children.

OBJECTIVE: This study investigated the effects of trauma to primary teeth, related by age at the time of injury and type of injury sustained, to the frequency and type of developmental disturbances in the permanent successor teeth in a representative population of Maltese children. METHOD AND MATERIALS: Thirty-two children with 67 traumatized primary teeth were examined and any developmental disturbances of the corresponding permanent teeth recorded. RESULTS: Altogether, 52.2% of the permanent teeth exhibited developmental disturbances following trauma to their primary predecessors. The highest frequency of malformations was found following subluxation injuries. Intrusion injuries were associated with the most severe malformations. Age at the time of trauma to the primary dentition was a principal factor in the risk and severity of malformations developing in the permanent successors. CONCLUSION: The extent of malformation of the developing tooth germ was highly related to its developmental stage and to the severity and type of trauma sustained by the primary incisor.

Unerupted incisors--characteristic features and associated anomalies.

The aims of this study were to investigate the association of unerupted incisors with other dental anomalies and to indicate the aetiological and clinical relevance of such associations. Forty-one patients with unerupted incisors were examined. The group comprised 30 males and 11 females, ranging in age from 7 to 39 years. The patients were assessed for nine dental anomalies: hyperdontia, hypodontia, microdontia, enamel hypoplasia, infraocclusion of the primary molars and ectopia of the canines, premolars, first permanent molars, and second permanent molars. The patients were matched with respect to age and gender to 41 consecutively selected control subjects with similar selection criteria but no history of problems with incisor eruption. The prevalence rates of the dental anomalies in association with failure of eruption of incisors were compared to the reference rates in the control group by means of Pearson chi-square tests. The results of this study revealed that unerupted incisors were more frequent in males than in females. A statistically significant association (P = 0.006) was found between unerupted incisors and other inherited dental anomalies, namely ectopic teeth, hyperdontia, and enamel hypoplasia. Unerupted incisors may be considered part of a spectrum of inheritable dental anomalies.

Double transmigration and hyperdontia.

Transmigrated teeth are rare, though reports have increased with the advent of panoramic radiography. Ectopic eruption of canines and other dental anomalies as retained deciduous teeth and supernumerary teeth have a genetic etiology and may be linked. A case report is presented which exhibits transmigration of both a mandibular canine and lateral incisor as well as the presence of a supplemental premolar and retained deciduous molar roots. The possible etiology of these abnormalities is discussed.

Runx2 and dental development.

The Runx2 gene is a master transcription factor of bone and plays a role in all stages of bone formation. It is essential for the initial commitment of mesenchymal cells to the osteoblastic lineage and also controls the proliferation, differentiation, and maintenance of these cells. Control is complex, with involvement of a multitude of factors, thereby regulating the expression and activity of this gene both temporally and spatially. The use of multiple promoters and alternative splicing of exons further extends its diversity of actions. RUNX2 is also essential for the later stages of tooth formation, is intimately involved in the development of calcified tooth tissue, and exerts an influence on proliferation of the dental lamina. Furthermore, RUNX2 regulates the alveolar remodelling process essential for tooth eruption and may play a role in the maintenance of the periodontal ligament. In this article, the structure of Runx2 is described. The control and function of the gene and its product are discussed, with special reference to developing tooth tissues, in an attempt to elucidate the role of this gene in the development of the teeth and supporting structures.

Maxillary canine anomalies and tooth agenesis.

The aims of the study were to analyse the records of 26 subjects (18 females, eight males) with maxillary canine-first premolar transposition (Mx.C.P1) together with 160 subjects with a palatally displaced canine (PDC) to determine the pattern of tooth agenesis in these cases and to compare them with similar samples reported in the literature. A strong association between Mx.C.P1, lateral incisor and lower second premolar agenesis was found, with a 20 per cent prevalence of lateral incisor agenesis and a 24 per cent prevalence of lower second premolar agenesis. There was a lesser association with third molar (M.3) agenesis, with a prevalence of 52.2 per cent. Weaker associations were found for a PDC, with a prevalence of 5 per cent for lateral incisor agenesis. The prevalence of lower second premolar (5 per cent) and M.3 (27.5 per cent) agenesis approached reference values. Evidence for the implication of the MSX1 or PAX9 genes in the aetiology of PDC was weak.

Transmigration of mandibular canines--a review of the literature and a report of five cases.

Transmigration of the mandibular permanent canine is a rare event, the etiology of which is not clear. We present five cases of transmigrated mandibular canines together with a review of the literature, a discussion of the etiology, and the treatment options.