Therapeutic reassessment of impacted or transposed teeth / Réévaluation thérapeutique des dents incluses ou transposées

Introduction: Impacted or transposed teeth present a common yet challenging issue in dentistry. These conditions occur when teeth fail to erupt properly or emerge in abnormal positions within the dental arch. Material and Method: This article explores the evolving landscape of therapeutic strategies for impacted or transposed teeth, emphasizing a multidisciplinary and patient-centered approach. Results: By adopting a multidisciplinary approach involving orthodontists, oral surgeons, and other dental specialists, clinicians can tailor treatment plans to address individual needs and optimize outcomes. Discussion: Therapeutic reassessment of impacted or transposed teeth represents a paradigm shift in modern dentistry, emphasizing personalized care, minimally invasive techniques, and interdisciplinary collaboration.

Introduction: Les dents incluses ou transposées présentent un problème courant, quoique difficile à gérer. Ces conditions surviennent lorsque les dents ne parviennent pas à faire leur éruption correctement ou émergent dans des positions anormales au sein de l'arcade dentaire. Matériel et méthode: Cet article explore le paysage évolutif des stratégies thérapeutiques proposées pour la prise en charge des dents incluses ou transposées, en mettant l'accent sur une approche multidisciplinaire centrée sur le patient. Résultats: En adoptant une approche multidisciplinaire réunissant des orthodontistes, des chirurgiens oraux et d'autres spécialistes dentaires, les cliniciens peuvent adapter les plans de traitement au mieux pour répondre aux besoins individuels de chaque patient et optimiser les résultats. Discussion: La réévaluation thérapeutique des dents incluses ou transposées représente un changement de paradigme en dentisterie moderne, mettant l'accent sur les soins personnalisés, les techniques mini-invasives et la collaboration interdisciplinaire.

Influence of orthodontic bracket prescription on smile attractiveness in patients with different sagittal skeletal patterns: A 3-dimensional cross-sectional study.

INTRODUCTION: The objective of this study was to evaluate the influence of orthodontic bracket prescription on smile attractiveness. METHODS: Three women were chosen according to their sagittal skeletal pattern: skeletal Class I, II, or III malocclusion. For each, 3 smiling pictures were taken in frontal, oblique, and lateral views. The maxillary arch was then scanned, and a 3-dimensional digital model was constructed on the OrthoAnalyzer software. The information of 3 orthodontic prescriptions, namely Roth, MBT, and Ricketts, was simulated after the virtual placement of orthodontic brackets on 10 maxillary teeth. The simulations were then superimposed on the smile photographs in the 3 views, creating a total of 27 images. Groups of orthodontists, dentists, and laypeople rated the attractiveness of each smile using the visual analog scale. RESULTS: This study included 167 evaluators: 54 orthodontists, 54 dentists, and 59 laypersons. In terms of orthodontic prescription, MBT esthetic scores were 4% lower than Roth scores (P <0.001), and Ricketts scores were 13.6% lower than Roth scores (P <0.001). In terms of skeletal pattern, Class II and III scores were 15.0% and 16.4% lower than Class I scores, respectively (P <0.001). Regarding the smiling view, oblique view scores were 3.1% lower than frontal view scores (P = 0.031), whereas lateral view scores were 8.4% lower than frontal view scores (P <0.001). In contrast to gender and age, the specialty of the evaluators significantly affected the esthetic rating of the smiles. CONCLUSIONS: The attractiveness of a smile is affected by the prescription of the brackets. The Roth prescription tends to obtain the most favorable esthetic scores, especially in sagittal smiling images. Profile smiles with excessively proclined incisors are considered unattractive. Different views of the same smile do not get similar esthetic scores because sagittal views are rated the most severely.

Evaluation of shear bond strength and adhesive remnant index of metal APC™ Flash-Free adhesive system: A comparative in vitro study with APC™ II and uncoated metal brackets.

OBJECTIVE: The aim of this in vitro study was to compare the shear bond strength (SBS) and the adhesive remnant index (ARI) of the metal APC™ Flash-Free adhesive system, the APC™ pre-coated adhesive system and a conventional uncoated system. MATERIALS AND METHODS: One hundred eighty-six freshly extracted human premolars were randomly divided into 3 groups and bonded by a single operator. Group A/Control Group (60 teeth): the manual bonding group treated with Transbond™ XT Light Cure Adhesive Paste (3M™ Unitek). Group B (60 teeth): treated with APC™II metal maxillary premolar precoated brackets. Group C (66 teeth): treated with metal maxillary premolar APC Flash-Free brackets. The teeth were then stored in distilled water at 37̊C for 24hours, and five hundred cycles of thermocycling were performed. The Shear Bond Strength (SBS) test was performed using an Instron Universal Testing Machine, and the adhesive remnant index (ARI) was determined using a dental optical microscope at ×25 magnification. RESULTS: The mean shear bond strength values showed differences between the three types of brackets (P=0.016; Anova). It was significantly higher with APC™II and lower with APC Flash-Free brackets; however, no significant differences were found between conventional and APC Flash-Free brackets (P-value=0.574). The distribution of the dichotomized ARI score was significantly different between the three brackets (P-value=0.049). The ARI score for APC Flash-Free brackets was higher with no significant difference between the conventional system and APC brackets (P-value=0.361). CONCLUSIONS: The mean SBS values were not significantly different between APC Flash-Free metal brackets and uncoated metal brackets. The APC Flash-Free metal system's bond failure occurred at the bracket-adhesive interface, with the highest percentage of teeth having more than 50% of the residual composite on the enamel after debonding.

Comparative study of excess glue around metallic APC™ Flash-Free adhesive system / Étude comparative des excès de colle autour des attaches métalliques préencollées APC™ Flash-Free

Introduction: The aim of this in vitro study was to determine if there is a significant difference in the excess adhesive flash between the metallic APC™ Flash-Free adhesive system, the APC™ pre-coated adhesive system and a conventional uncoated system. Materials and Methods: One hundred eighty-six freshly extracted human premolars were randomly and blindly divided into three groups according to the type of brackets. Group A (control group n=60): The conventional uncoated metallic bracket (Victory, 3M Unitek®) with a Transbond XT™ Light Cure Adhesive Paste was used. Group B (n=60): The APC™ II metallic maxillary precoated premolar brackets was used. Group C (n=66) : The metallic APC™ Flash-Free adhesive system without flash clean up was used. Images were taken at 40 magnifications in a dental microscope (Leica M320 for dental, Wetzlar, Germany) then analyzed with the ImageJ software and the area of excess adhesive flash was measured. Results: The mean percentage was significantly different between the three groups (p<0.001; ANOVA). It was significantly smaller for brackets in the APC Flash-Free group (p<0.001), and the difference was not significant between conventional brackets and APC (p=0.224). Discussion: The new technique seems to reduce the amount of excessive adhesive around orthodontic brackets.

Introduction: L'objectif de cette étude in vitro était de présenter une évaluation comparative et objective de l'efficacité d'une nouvelle technique d'attaches métalliques préencollées APC™ Flash-Free fabriquées par 3M Unitek®, éliminant l'étape de nettoyage grâce au système de fibres non tissées. Matériels et méthodes: Cent quatre-vingt-six prémolaires humaines saines fraichement extraites sont réparties en trois groupes de façon randomisée. Groupe A : 60 dents sont collées avec des attaches conventionnelles à encoller avec du Transbond XT™ (3M Unitek®). Groupe B : 60 dents sont collées avec des attaches préencollées APC™ II préenduites du même type de pâte adhésive. Groupe C : 66 dents sont collées avec des attaches APC™ Flash-Free (3M Unitek®), puis observées avec un microscope (Leica M320 for dental, Wetzlar, Germany) sous un agrandissement x40. Les photographies sont analysées à l'aide du logiciel ImageJ. Résultats: Les comparaisons multiples de Tukey ont montré que le pourcentage moyen était significativement plus petit au niveau des attaches du groupe C, APC™ Flash-Free (p-value<0,001), mais la différence n'a pas été significative entre les attaches conventionnelles du groupe A et celles préencollées du groupe B (p-value=0,224). Discussion: La technique de pointe adoptant un matériau non-tissé a l'air de réussir à réduire l'excès d'adhésif périphérique.

Effects of enamel deproteinization with different application times on the shear bond strength of a self-etching primer: An in vitro study.

OBJECTIVE: The aim of this in vitro study was to evaluate the effects of enamel deproteinization on the shear bond strength of a self-etching primer Transbond Plus™(TBP), with different application times of sodium hypochlorite (NaOCl 5.25%), primarily and secondarily on the adhesive remnant index score. MATERIALS AND METHODS: One hundred twenty-five freshly extracted human premolars were randomly and blindly divided into five groups according to the enamel surface preparation, as follows (n=25): group 1(control): Etching with 37% phosphoric acid for 15seconds+Bonding; group 2 (control): TBP™ without NaOCl, group 3: 60seconds NaOCl+TBP™, group 4: 30seconds NaOCl+TBP™, group 5: 15seconds NaOCl+TBP™. The same composite resin was used (Transbond XT™) to bond the orthodontic metal brackets. After the immersion of the teeth in distilled water at 37°C for 24hours the shear bond strength was measured using the universal testing machine and the adhesive remnant index score (ARI) was evaluated under an optical microscope (25×). RESULTS: The mean SBS values (inMPa) of the groups were respectively: group 1: 13.03±5.36; group 2: 12.28±3.06; group 3: 12.38±4.55; group 4: 12.98±5.76; and group 5: 11.73±5.67. Enamel deproteinization increased the SBS for groups 3 and 4, but no statistically significant difference was found between the five groups (P=0.883). Group 1 showed the highest ARI scores, with 52% of the teeth retaining all the adhesive (score 3). However, for all the other groups, scores 0 and 1 were predominant, with less than half of the adhesive or no adhesive at all remaining on the teeth. CONCLUSIONS: Enamel deproteinization with sodium hypochlorite (5.25%) and the variation of its application time has no effect on the SBS of the self-etching primer Transbond Plus ™.

Correlation between fusion of spheno-occipital synchondrosis and cervical vertebral maturation: A CBCT and cephalometric assessment.

OBJECTIVE: The aim of this study was to determine among young orthodontic patients the relation between the spheno-occipital synchondrosis (SOS) fusion and the cervical vertebral maturation (CVM) and to look for an eventual impact of gender, skeletal class and vertical pattern on their association. MATERIAL AND METHODS: CBCT scans and lateral cephalometric radiographs of 117 patients, aged between 8 and 18 years, were selected. SOS fusion was assessed on a mid-sagittal cut of the CBCT scans. CVM was evaluated on the lateral cephalograms as well as ANB and GoGn-SN angles. Spearman correlation test was used to assess the relationship between SOS and CVM. Fisher's exact test was performed at every CVM stage to analyse the association between SOS and other variables (gender, skeletal class, and vertical pattern). Cohen's kappa analysis was used for reliability. RESULTS: A strong correlation was found between SOS maturation and CVM (r=0.852, P<001). Fisher's exact test indicated significant association only between gender and SOS in CVM stage 2 group, and between vertical pattern and SOS in CVM stage 4. Cohen's kappa analysis showed moderate inter and intra-rater reliability for CVM index (k=0.50 and 0.53 respectively, P<.001), strong inter-rater reliability (k=0.80, P<.001) and almost perfect intra-rater reliability (k=0.85, P<.001) for SOS index. CONCLUSIONS: SOS fusion correlates well with CVM and might be a reliable tool for skeletal maturation assessment. Girls seem to have an earlier fusion of SOS in relation to their respective CVM compared to boys, and the vertical pattern could influence the association between SOS and CVM stages.

Evaluation of the ideal position of the maxillary incisor relative to upper lip thickness.

INTRODUCTION: The anteroposterior position of the maxillary incisors has been studied since the beginning of cephalometric research. Most reports of ideal position have been based on measurements made on subjects with Class I occlusion without consideration of other facial variables. However, the ideal position is reflected in the soft tissues by the position of the lips. The purpose of this study was to consider the position of the maxillary incisor relative to other factors, including the thickness of the upper lip, and to evaluate its most aesthetic position using profile photographs. METHODS: The subjects in this study were 130 patients with Class I occlusion; their sex, age, thickness of the upper lip, and angular position of the maxillary incisor were recorded. From these 130 patients, 70 profile photographs that met the inclusion criteria were chosen for further evaluation. A survey was conducted among 60 lay people, 60 dentists, and 60 orthodontists. They were asked to classify the sets of photographs, from the most esthetic position of the upper lip to the least esthetic. RESULTS: For patients with thin lips, raters tended to prefer a more protruded position of the incisor than normal or between 8.0 mm and 11.5 mm in front of the Na-B bone and 4 mm in front of the Na-A bone. For patients with thick lips, the position of the incisor did not affect the perception of the profile. CONCLUSIONS: A correct skeletal scheme or Class I occlusion does not necessarily result in ideal facial harmony. Therefore, it will be necessary to consider all the factors that come into play, especially the lips, which are a key element in facial esthetics.

Estimation and Comparison of the Duration of the Pubertal Peak in Skeletal Class II and Class I Subjects Using the Cervical Vertebrae Maturation Index Method.

AIM: The purpose of this study is to estimate and compare the duration of the pubertal peak in skeletal class II and class I subjects and to detect any difference between boys and girls or between hypo-, normo-, and hyperdivergent subjects for skeletal maturation indicator (CVM) in white Caucasians. MATERIALS AND METHODS: 346 subjects were selected from 3,119 examined files. Pretreatment lateral cephalometric records were hand-traced and divided following the anteroposterior skeletal relationship, the gender, the vertical pattern, and the skeletal maturation. The duration of the pubertal peak was calculated based on the chronological age interval according to each group. The age of onset of the active growth and the duration of the pubertal peak were compared between the different groups studied. RESULTS: Pubertal peak had a mean duration of 13 months in skeletal class I subjects, 19 months in skeletal class II subjects, 15 months in girls, 20 months in boys, 13 months in normodivergent and hypodivergent subjects, whereas in hyperdivergent subjects, it lasted 18 months. CONCLUSION: The growth interval corresponding to the pubertal growth spurt (CS3-CS4) was (1) significant between skeletal class I and class II subjects, (2) longer in boys, and (3) longer in hyperdivergent subjects. CLINICAL SIGNIFICANCE: Orthodontic treatments can start earlier for girls in class I or class II relationship and for hyperdivergent subjects as well. Furthermore, boys and subjects in class II skeletal relationship have a significantly longer duration of the pubertal peak and consequently a much efficient orthopedic and orthodontic treatment.

Evaluation of preferred lip position according to different tip rotations of the nose in class I young adult subjects.

INTRODUCTION: The mouth plays an important role in the overall aesthetic appearance of the face. The aims of this study were to determine the optimal antero-posterior (AP) lip position relative to various rotations of the nasal tip and assess the impact of the nasolabial angle on facial aesthetics. MATERIAL AND METHODS: Three-dimensional facial volumes, in motion, of one Caucasian male and one Caucasian female with a Class I malocclusion and an orthognathic profile were modified to alter the nasal tip rotation (3 rotations) and the AP lips position (6 positions). 72 generated models were created in two and three-dimensions. Generated models were rated online by 60 dentists, 60 orthodontists and 60 laypeople, using a Visual Analogue Scale. Scores were analysed according to lip position, rater's profession and gender. RESULTS: General agreement was found between all groups on the most and least preferred lip positions. No differences between male and female raters were found. All raters were more influenced by the 3-dimensional rotating facial volume than by 2-dimensional angles. Similar angular values for the nasolabial angles were found in the most and least preferred profiles, showing that the most influential factor in facial aesthetics was the lip position, and stressing the need to evaluate each component of the nasolabial angle independently. CONCLUSION: The lip position was the determinant factor in facial aesthetics with little influence of the nose tip rotation. Three-dimensional evaluation of the nose and lip were needed to establish a soft tissue-based treatment plan.

Association between sella turcica bridging and palatal canine impaction: Evaluation using lateral cephalograms and CBCT.

INTRODUCTION: The purpose of this study was to find a correlation between sella turcica bridging and the presence of a palatal impacted canine, using lateral cephalograms and CBCT. MATERIAL AND METHOD: We selected the lateral cephalograms and CBCTs of 60 patients meeting specific criteria. The radiographs were analysed to study the relationship between sella turca bridging and several factors. The presence or absence of a partial or total bridging was deducted by measuring the dimensions of the sella turcica and by using an accurate scoring system. RESULTS AND CONCLUSION: Our study did not show any statistically significant association between sella turcica bridging as diagnosed on the lateral cephalogram and the CBCT images and the following factors: age, gender, facial type, skeletal class and the presence of an impacted canine. We found a significant difference for the classification of the sella turcica between these two radiographic methods.

[The orthodontic surgical approach revisited]. / L'approche orthodontico-chirurgicale revisitée.

An adequate orthodontic preparation is a key to success of every orthognatic surgery. Therefore, the detection and the correction of the existing dentoalveolar compensation tend to favor the correction of the skeletal defects. The pre-surgical orthodontic goals have to be defined at the beginning of the treatment, thus, not always achieving a complete leveling of the arches, nor a final space closure and ideal intercuspation. The orthodontic preparation aims to guide the surgical skeletal displacements. Many dentoalveolar compensations can be identified as specific to different types of malocclusion. Accordingly, an adequate individualized planning and a good coordination between both orthodontist and surgeon, are of a major importance, in order to avoid unexpected traps during orthodontic pre-surgical preparation.