Although treatment with fixed or mobile appliances has become an important part of modern orthodontics, side effects such as white spot lesions (WSLs) have a negative impact on the aesthetic outcome of orthodontic treatment. The purpose of this article was to review current evidence on the diagnosis, risk assessment, prevention, management and post-orthodontic treatment of these lesions. Data collection was performed electronically, and the initial search using the keywords “white spot lesions”, “orthodontics”, “WSL”, “enamel” and “demineralization” in different combinations resulted in 1032 articles for the two electronic databases used. Ultimately, a total of 47 manuscripts were considered relevant to the aim of this research and included in this review. The results of the review indicate that WSLs remain a significant problem during orthodontic treatment. According to studies in the literature, the severity of WSLs correlates to the duration of treatment. Using toothpaste with more than 1000 ppm fluoride at home reduces the frequency of WSL separation and regular application of varnishes in the office reduces the frequency of the occurrence of WSLs only in the context of maintaining a strict hygiene regime. The old hypothesis that elastomeric ligatures retain more dental plaque than metal ones has been refuted. There are no differences in the appearance of WSLs between conventional brackets and self-ligating brackets. Clear aligner mobile devices develop fewer WSLs but are more extensive as opposed to conventional fixed devices, while lingual orthodontic appliances have a lower incidence of WSLs, and the most effective device for preventing these lesions is WIN, followed by Incognito.

The use of maxillary expanders has the effect of distancing the maxillary bones at the level of the median palatal suture. During maxillary expansion, the main resistance forces occur at the zygomatico-maxillary sutures, and not in the median palatal suture, which is the basic principle on which this method is based. In this observational study, we evaluated possible complications at the skeletal and dentoalveolar level after palatal split using miniscrew-assisted rapid palatal expansion (MARPE) associated or not with corticopuncture (CP) therapy. The study included 27 patients with maxillary transverse deficiency and unilateral or bilateral cross-bite. Skeletal and dentoalveolar changes were evaluated using cone beam computed tomography (CBCT) images acquired before and after expansion. The mid-palatal suture was separated in 88.88% of cases, buccal bone height of the alveolar crest had decreased at first molar both at oral and palatal level by approximately 2.07 mm in 40.7% of cases whilst the remaining 59.3% showed insignificant bone loss, with canines exhibiting buccal tipping of 4.10° in 62.5% of cases. Changes of the occlusal planes were observed in 10 cases (37%). Maxillary canines tended to show symmetric buccal inclinations relative to the maxillary basal bone. Six patients; 22.22% showed hypertrophy/hyperplasia of the palatal mucosa associated with ulcerations, erythema, itching, and discomfort in the area. Swelling at the mid-palatal suture after split was observed in all cases and was caused by the resultant force. No cases of necrosis of the palatal mucosa were observed. Although occlusal modifications occur after palatal split, especially in unilateral cross-bite cases, these changes can be treated with the help of fixed orthodontic appliances.

At the end of any orthodontic treatment, retention is a necessary phase. Unfortunately, the current retention devices and the lack of proper oral hygiene on the part of patients lead to the accumulation of dental plaque, periodontal inflammation, and gingival retraction. Our retrospective study included 116 adult patients wearing various types of orthodontic retainers. To quantitatively determine the accumulation of dental plaque, we used the Quigley–Hein plaque index modified by Turesky and the Navy plaque index modified by Rustogi. Another studied parameter was related to the gingival recession associated with retention devices. We had investigated the correctness of patients’ dental hygiene, their preferences for auxiliary means of oral hygiene, the consistency with which they wear the mobile retainers, and respect the orthodontist’s instructions; we also investigated the inconveniences and the accidents that may occur during the retention period. Statistical analysis showed that plaque accumulation is significantly lower in the case of mobile retainer than fixed retainer wearers; the exception was the Hawley plate, where the interdental plaque was more than in all the other studied retainers. Periodontal recessions were more frequent in the case of fixed retainer wearing. Flossing was the most commonly used auxiliary mean for oral hygiene. The compliance of women in wearing vacuum-formed retainers was better than that of men. Patients with a class III history had more plaque accumulation, and class II/1 had the most problems related to detachment/damage of fixed retainers. Mobile retainers proved better results for oral hygiene, but fixed retainers cannot be waved.

The purpose of this in vitro study was to analyze and identify a methodology for the improvement of the shear bond strength of orthodontic brackets bonded with two orthodontic adhesive systems considered to be widely used, Transbond Plus Color Change with Transbond Plus Self-Etching Primer and Fuji Ortho LC with orthophosphoric acid under various enamel conditions: dry, moistened with water and moistened with saliva. The sample size included a group of 120 freshly extracted premolars distributed into six study groups, each one of 20 teeth. A universal testing machine was used to detach the brackets. We determined and compared the strength of the two studied adhesive systems used in different enamel surface conditions. The mean shear bond strength values in groups 1 (TPCC, TSEP, dry), 2 (TPCC, TSEP, water), 3 (TPCC, TSEP, saliva), 4 (Fuji Ortho LC, etched, dry enamel), 5 (Fuji Ortho LC, etched enamel, water) and 6 (Fuji Ortho LC, etched enamel, saliva) were 15.86, 12.31, 13.04, 15.27, 14.14 and 13.11 MPa, respectively. ANOVA test and Student’s t-test showed significant differences between groups. While clinically acceptable shear bond strengths were obtained for all six studied groups, a particular outcome that to the authors’ knowledge has not been documented elsewhere has been obtained: in case of water contamination, it is preferable to use Fuji Ortho LC instead of Transbond Plus.

Fixed orthodontic therapies include several procedures that can affect the enamel surface. The aim of this study was to assess the action of composite resin on the surface of the tooth through variation of enamel changes after debonding metal and ceramic brackets, by means of scanning electron microscopy. An in vitro study was conducted on 48 human premolar specimens, which were extracted within a period of two months for orthodontic purposes. On half of them, metal brackets were bonded, and on the other half, ceramic brackets (Al₂O₃) were bonded, using light cure adhesive paste and a two-step, etch-and-bonding technique. The brackets were debonded after 24 h using a straight debonding plier. The adhesive remnant index (ARI) was determined by visual observation of the specimen. Post-debonding scans were aligned with the baseline, and the surfaces’ changes were quantified. A quantitative analysis was made on the debonded brackets to determine the presence or absence of enamel on the base pad. Evaluation of pre-bonded and post-clean-up enamel surface revealed no crack and increased roughness in both ceramic and metal brackets, which was higher for the ceramic ones. The enameled band (perikymata), artificial caries, or the superficial fissures revealed in the pretreatment stage were replaced with the loss of the prismatic structure and the presence of remnant adhesive. No enamel substance was found on the base pad. The ARI_tooth was higher for metallic brackets than for ceramic ones. Metallic brackets and ceramic brackets have undergone mechanical changes by showing fractures in their structure. According to our present investigation, we can conclude that the adhesive composite resin is safe for use on both metal and ceramic brackets in orthodontic treatments, with no iatrogenic enamel damages.

Impression materials are used to record and reproduce the exact morphology of the patient’s oral cavity. The dimensional stability of a material is its ability to maintain the accuracy of recording the details of the oral cavity for a longer period of time, including the time during imprinting and immediately after. The aim of this study was to evaluate the accuracy of three different impression materials commonly used in the dental practice with the aid of an extra-oral three-dimensional (3D) scanner using an in vitro analysis. A typodont tooth model of the maxillary dental arch and mandibular dental arch, containing 16 permanent teeth, was used for evaluation. With the aid of three different impression materials, this model was imprinted fifteen times, resulting in fifteen different plaster models. A capsule extra-oral scanner device was used to digitalize the models and the same device was later used to align, compare, and measure scanned model surfaces. After performing the Kruskal–Wallis test for each measurement category (model), only two out of the fifteen measurements showed statistically significant differences between the material groups: vestibular-oral and mesial-distal width. Post hoc analysis showed that the alginate model (mean range = 29.13) had significantly higher bias scores than the addition silicone model (mean range = 16.75) (z = 2.501, p = 0.037). The difference between the average values of the model bias made from condensation-based silicone and addition-based silicone was initially significant, but after applying the Bonferroni correction for further comparisons, this relationship did not remain significant (z = 2.197, p = 0.084). Addition-based silicone models had the highest accuracy in terms of fidelity, followed by condensation-based silicones, and then by alginate models. Silicone-based impression materials improved over time, being highly used in all areas of dentistry. Alginate impressions had the lowest pattern of accuracy among those studied.