Effect of bleaching treatments on the adhesion of orthodontic brackets: a systematic review.

BACKGROUND: Nowadays bleaching procedures have gained popularity in orthodontic patients. Peroxide and Carbamide acids are the common agents which are used in in-office and at home bleaching techniques. Consequently, the Bonding adhesion to the enamel can be influenced by the orthodontic phase and the residual peroxide might interfere with the polymerization and the adhesion of the brackets. Frequent debonding of the brackets from teeth after the bleaching procedure could cause the lengthening of the therapy and promote irregularities on enamel surface derived from an additional bonding phase of the brackets. The aim of this systematic review is to appraise the influence regarding the effect of the bleaching procedure on the bond strength of orthodontic brackets. METHODS: An electronic database search was performed. Search terms included: bleaching, brackets, adhesion; data were extracted and summarized. Risk of bias was assessed using the Chocrane risk of bias tool, adapted for in vitro studies. RESULTS: A total of 8689 articles were screened and 11 studies met the inclusion criteria of this systematic review. 1000 teeth of human and bovine origin were analyzed for the shear bond strength (SBS) of stainless and ceramic brackets after the bleaching treatments. All the authors divided the groups in different subgroups with different bleaching agents and in different concentration. The SBS value allowed to demonstrate the necessity to delay the bonding of the brackets for two weeks after a bleaching treatment and its improvement when tooth mousse or antioxidants agents are used. CONCLUSIONS: The SBS values and the delay of the bonding procedure must be considered in dental practice and clinical strategies are necessary in order to avoid drawbacks which could cause the debonding of the brackets after bleaching due to the alterations of the dental substrate, thus interfering with the orthodontic treatments.

Cervical Range of Motion Analysis Performed with an Accelerometer: A Study of Intersession Reliability for Dental Practice.

During the clinical examination of subjects with temporomandibular disorders (TMDs), the dentist sometimes must evaluate the cervical spine, due to the anatomical and functional connections between the cervical portion of the spine and the stomatognathic apparatus. The accelerometer is a device that evaluates the Range of Motion (ROM) of the main movements of the head on the neck. To date, only a few studies have investigated the repeatability of the use of the accelerometer in the assessment of cervical ROM. Therefore, the present longitudinal observational study analyzed the repeatability of acquired cervical movements on a sample of volunteer subjects who underwent accelerometer testing. A sample of 32 subjects was tested twice within 14 days to assess cervical ROM using a standardized protocol based on a review of existing literature. The results show that the examination is reliable for all the positions of the jaw, except for the parameters regarding the asymmetries of rotation and bending. In conclusion, the accelerometer can be considered a reliable tool for evaluating the active cervical ROM. However, further studies will be necessary to make better evaluations.

Full-Digital Workflow for TMDs Management: A Case Series.

Temporomandibular joint disorders (TMDs) have always been the subject of studies due to the difficult management of symptoms and the complex stabilization of the so-called therapeutic position. In this effort, digital technologies open new opportunities for such planning, allowing the clinician to digitally assess the situation and verify the stability of the new position from a functional point of view. The present case series shows examples of preliminary full-digital planning of treatment in TMDs patients made with the preliminary evaluation of the kinematic activity of the mandible through a digital device (Tech in motion™, ModJaw, Villeurbanne, France). Three TMD clinical cases are analyzed with full-digital techniques and workflow. A personalized treatment for each case was digitally planned on the base of proper kinematic tracings recorded for each patient, and intraoral appliances were digitally customized through a full-digital or semi-digital workflow. The digitalization of mandibular kinematic gave us the possibility of making a more "aware" diagnosis, especially in a dynamic key, and then it allowed a faster realization and execution of the intraoral appliance through a digital workflow, memorizing the therapeutic position and early checking the device, before its realization, on the real kinematics of the patient.

Analysis of Cervical Range of Motion in Subjects Affected by Temporomandibular Disorders: A Controlled Study.

Background and Objectives: The aim of this study were to compare the cervical ROM data obtained from accelerometer exams between patients suffering from TMDs (study group) and healthy patients (control group). Material and Methods: A sample of 43 young adult subjects (23 control subjects and 20 TMD patients) were included in this study and analyzed with the accelerometer (Baiobit™, BTS, Garbagnate Milanese, Milan, Italy) to assess cervical ROM using a standardized protocol, including the following occlusal conditions: mandibular rest position, clenching, clenching with cotton rolls, maximal intercuspation, and mandibular position with cotton rolls. The cervical ROM was measured in degrees and expressed as the mean and standard deviation. Results: TMD patients showed a reduced cervical extension compared to control subjects in all the conditions, with statistically significant relevance. Regarding the other movements, the differences were not statistically or clinically significant. Conclusions: Based on the results of the present study, it can be observed that temporomandibular disorders are associated with a decreased cervical extension range, while the remaining components of ROM do not seem to be significantly associated. The use of accelerometers in ROM analysis could be helpful in improving interdisciplinary communication between dentists and physiotherapists.

Effects of an Ozonated Water Irrigator on the Plaque Index and Bleeding Index of Pregnant Women.

Pregnancy causes physiological changes in the woman's body, which can also affect oral health. Therefore, pregnant women may manifest gingival inflammation that is favored by their hormonal increase. This clinical trial (ClinicalTrials.gov Identifier: NCT04140643) evaluated the variation in the plaque index (PI) or bleeding index (BOP) in pregnant women after daily use of an ozonated water irrigator and proper home oral hygiene, compared to a control group who only performed home oral hygiene. The inclusion criteria were the gestation period from the 14th week to the 30th week, a diagnosis of gingivitis, and a minimum number of teeth equal to 20. The PI and BOP index were evaluated at T0, fifteen days after T0 (T1), and two months after T1 (T2). The PI values systematically decreased over time (F (1.19) = 41.82) in both groups, with a systematic difference in PI values between the two groups (F (1.19) = 6.28, p = 0.021). A statistically significant difference was assessed in the BOP index at T2 between the two groups, with the control group suffering a higher BOP index. The results show that the patients in the study group showed a decrease in the BOP index over the three time points, in contrast to the control group, due to the beneficial properties of ozonated water.

Metal versus Fiberglass Post-Orthodontic Retainers Short-Term Effects on Plaque Index and Microbial Colonization: An Observational Study.

In orthodontics, post-treatment retention phase is crucial for maintaining the obtained clinical results. In cases of crowding, a bonded fixed retainer is often chosen to maintain teeth alignment in the anterior sector of the lower dental arch. A fixed retainer can remain in the mouth for years. Therefore, it is important that it is applied with harmless materials for the level of plaque control. The present study aimed to investigate the salivary concentrations of Streptococcus mutans (S. mutans) and Lactobacilli, and the Sillness and Loe plaque index, in patients wearing metal wire versus fiberglass orthodontic retainers. Forty post-orthodontic patients were included in the sample: in 20 subjects a metal wire retainer was applied (MR), while in the others a fiberglass retainer was applied (FR). The variables were recorded at baseline (T0), after 1 month (T1), and after 2 months (T2) of follow-up. The percentage of patients with a level of S. mutans and Lactobacilli colonization > 105 increased over time in the FR group (T0 = 0%, T1 = 5%, T2 = 35%), compared with the MR group. PI increased in the FR group (T0 = 0, T1 = 14, T2 = 27), and remained almost the same in the MR group (T0 = 3, T1 = 0, T2 = 2). From the present results it appears that the metal wire retainer is better than the fiberglass retainer for the level of plaque control performed by the patients.

Correlation between Bruxism and Gastroesophageal Reflux Disorder and Their Effects on Tooth Wear. A Systematic Review.

Bruxism and gastroesophageal reflux (GERD) can lead to wear of the dental tissues. Wear has a mechanical or chemical origin, and it is of extrinsic or intrinsic type. Bruxism and GERD are two etiological factors of dental wear. The intrinsic mechanical wear (abfraction) of Bruxism and intrinsic chemical wear (erosion) of GERD are both involved in sleep disorders; indeed, they could have associations and act in synergy in dental wear. The purpose of this review was to find out the possible associations between bruxism and GERD and their effects on tooth wear. The research was conducted on PubMed and the Cochrane Library using the following Keywords/Mesh Terms: Tooth wear, Bruxism, Sleep Bruxism, Sleep Disorders, or GERD. Only systematic reviews and clinical studies performed exclusively on human subjects were included in the review. Initially, the research gave more than 630 results on dental wear, bruxism and GERD and after application of the inclusion criteria irrelevant studies were excluded, and 5 studies were finally included in this review. It was possible to observe the presence of some associations between the two problems (reflux and GERD) and hypothesize negative effects on tooth wear. This research revealed the presence of an interconnection between these three problems (reflux, GERD and tooth wear) that can further act in synergy by attacking the hard dental tissues both from a chemical (reflux) and mechanical (bruxism) point of view. The dentist could play a role of "sentinel" in a multidisciplinary team, intercepting these problems early in order to treat them in the most appropriate way. PROSPERO Registration Number: CRD42021234209.

One-Stage Virtual Plan of a Complex Orthodontic/Prosthetic Dental Rehabilitation.

In complex dental treatments, a preliminary virtual plan (VP) can minimise the probability of errors and increase the predictability of the achieved result. Digital technologies and artificial intelligence open more opportunities for such planning, as they can be applied at the early stages of clinical examination to develop a simultaneous VP of all stages of treatment. The present clinical case describes a one-stage entire VP combining all the stages of treatment: gnathological, orthodontic, and prosthetic rehabilitation, until the final result. This approach avoids the accumulation errors associated with multistage VP, in which one stage of planning follows the end of a previous stage. One-step VP also allows demonstrating to the patients the expected results of the restoration, which increases their motivation to initiate the treatment.

Hand-Carried Ultrasonography Instrumentation in the Diagnosis of Temporomandibular Joint Dysfunction.

Internal derangement (ID) in the temporomandibular joint (TMJ) is defined as a mechanical problem of the joint that interferes with its function. It is attributed to an abnormal interaction among the articular disc, condyle, and joint eminence. The aim of this study is to evaluate diagnostic efficacy of non-invasive hand-carried ultrasonography instrumentation (US) to provide high-level images for a correct diagnosis of ID. Twenty-eight ID patients, 15 female and 13 males, were examined both clinically and by MRI images in order to achieve a diagnosis of ID (using Helkimo index). Then, they were submitted to US examination with a 12 MHz transducer by using hand-carried instrumentation by a clinician that was blind to their diagnosis and clinical data. TMJ US examination was performed with the mouth closed and mouth open, with proper technique. Each position was then evaluated with two different orientations of the transducer. US showed acceptable results in identifying bone structures. Lower values of diagnostic efficacy were obtained for disc position during joint movements with respect to MRI images. MRI still represents the gold standard for the identification of joint structures. If not corroborated by clinical and anamnestic data, the diagnostic efficacy of US in identifying the position of the disc during opening and closing jaw movements appears limited than compared to MRI.

Rare case of skeletal third class in a subject suffering from Solitary Median Maxillary Central Incisor syndrome (SMMCI) associated to panhypopituitarism.

BACKGROUND: The median solitary maxillary central incisor syndrome (SMMCI) is a rare malformative syndrome consisting of multiple defects, mainly found on the body midline. It can be correlated to the etiopathological and phenotypic pattern of panhypopituitarism. This case-report describes the rare case of a patient suffering from SMMCI and panhypopituitarism, showing an unusual craniofacial morphology. CASE PRESENTATION: From the cephalometric analysis, a skeletal class III was identified (despite the other cases described in literature described as skeletal class II), derived from hypomaxillia and mandibular protrusion. A convex lip profile, with tendency to mandibular hyper-divergency, airway patency, anterior and posterior cross-bite were observed. At the clinical examination, a maxillary cant was evident on the frontal plane that appeared asymmetric, with the prevalence of the third lower part of the face. There were some dysmorphic signs such as: small nose, rectilinear eyelid line and reduced interocular distance. CONCLUSIONS: The present clinical case shows how, despite the literature, SMMCI can be associated with a III skeletal class, with maxillary hypoplasia and mandibular protrusion. The interdisciplinary collaboration between dentist and pediatrician is therefore important for the early interception of the malocclusions associated with these syndromes.