Temperature changes in the pulp chamber and bleaching gel during tooth bleaching assisted by diode laser (445 nm) using different power settings.

The aim of this in vitro study was to investigate the safety of using blue diode laser (445 nm) for tooth bleaching with regard to intrapulpal temperature increase operating at different average power and time settings. Fifty human mandibular incisors (n = 10) were used for evaluating temperature rise inside the pulp chamber and in the bleaching gel during laser-assisted tooth bleaching. The change in temperature was recorded using K thermocouples for the five experimental groups (without laser, 0.5, 1, 1.5 and 2 W) at each point of time (0, 10, 20, 30, 40, 50 and 60 s). As the average power of the diode laser increases, the temperature inside the pulp chamber also increases and that of the bleaching gel was significantly higher in all the experimental groups (p < 0.05). However, the intrapulpal temperature rise was below the threshold for irreversible thermal damage of the pulp (5.6 °C). Average power of a diode laser (445 nm) ranging between 0.5-2 W and irradiation time between 10-60 s should be considered safe regarding the pulp health when a red-colored bleaching gel is used. Clinical studies should confirm the safety and effectiveness of such tooth bleaching treatments. The outcomes of the present study could be a useful guide for dental clinicians, who utilize diode lasers (445 nm) for in-office tooth bleaching treatments in order to select appropriate power parameters and duration of laser irradiation without jeopardizing the safety of the pulp.

Comparing Airway Analysis in Two-Time Points after Rapid Palatal Expansion: A CBCT Study.

BACKGROUND: The aim of this study is to investigate the upper airway analysis at two-time points after the rapid maxillary expansion was performed, using cone-beam computed tomography. METHODS: Subjects from the Orthodontic Department at the Aristotle University of Thessaloniki with unilateral or bilateral posterior crossbite were screened according to the selection criteria. A sample size calculation was performed, and a total of 14 subjects were recruited. All subjects received a rapid maxillary expansion with a Hyrax-type device as part of their comprehensive treatment. A CBCT was taken before the treatment (T1), immediately after the expansion was completed (T2), and 6 months after (T3). Their upper airway was measured using the CBCT images. Airway volume (V) and minimal cross-sectional area (MCS) were extracted and compared using SPSS to analyze the means. RESULTS: A statistically significant difference was found between all time points regarding both V and MCS (p < 0.001, p = 0.001). There was a statistically significant increase in both V and MCS measurements immediately after RPE expansion (T1-T2) and six months after expansion (T1-T3). Between the end of expansion and 6 months after (T2-T3), there was a decrease in V and no statistical difference in MCS. CONCLUSIONS: RPE can significantly increase the volume and minimal cross-sectional area of the nasal passage airway.

Dental, Skeletal, and Soft Tissue Changes after Bone-Borne Surgically Assisted Rapid Maxillary Expansion: A Systematic Review and Meta-Analysis.

(1) Background: For non-growing patients with marked transverse maxillary deficiency, bone-borne surgically assisted rapid maxillary expansion (SARME) has been proposed as an effective treatment option. Objective: To evaluate the dental, skeletal, and soft tissue changes following bone-borne SARME. (2) Methods: An unrestricted systematic electronic search of six databases, supplemented by manual searches, was performed up to April 2023. The eligibility criteria included prospective/retrospective clinical studies with outcomes pertaining to objective measurements of dental/skeletal/soft tissue effects of bone-borne SARME in healthy patients. (3) Results: Overall, 27 studies satisfied the inclusion criteria. The risk of bias of the non-randomized trials ranged between moderate (20) and serious (4). For the two RCTs, there were some concerns of bias. Trials with outcomes measured at the same landmarks within the scope of the prespecified timeframe were deemed eligible for quantitative synthesis. Eventually, five trials were included in the meta-analysis. SARME was associated with a statistically significant lengthening of the dental arch perimeter immediately after expansion, along with a marginally significant decrease in palatal depth during the post-SARME retention period. Post-treatment SNA values exhibited no statistically significant change. (4) Conclusion: Current evidence indicates that bone-borne SARME constitutes an effective treatment option for adult patients with maxillary transverse deficiency. Further long-term randomized clinical trials with robust methodology, large sample sizes, and 3D evaluation of the outcomes are needed.

Three-Dimensional Cone-Beam Computed Tomography Evaluation of Changes in Naso-Maxillary Complex Associated with Rapid Palatal Expansion.

The introduction of Cone-Beam Computed Tomography (CBCT) in orthodontics has added a new tool to diagnosis and treatment planning. The aim of this prospective clinical trial was to investigate the changes in the dimensions of the naso-maxillary complex in growing patients after RPE using CBCT. A total of 16 growing children (8 females, 6 males) with a mean age of 11, 12 ± 1 and 86 years underwent RPE as part of their comprehensive orthodontic treatment. CBCT scans were obtained before RPE (T1), immediately after RPE (T2) and 6 months after RPE (T3). The dimensions of the nasal width, nasal floor and the aperture of the midpalatal suture were calculated in different coronal slices of CBCT. Evaluation of the mean value variance per measurement at the three time intervals were performed using the paired Wilcoxon signed-rank test. Differences between the three time intervals were assessed by performing Multiple Pairwise Comparisons. A statistically significant increase in all measurements was seen immediately after RPE expansion (T2-T1) and six months after expansion (T3-T1). Between the end of expansion and 6 months in retention (T3-T2), a decrease was observed for all measurements. RPE can cause expansion of the nasal cavity in growing patients. The expansion of the midpalatal suture follows a triangular pattern of opening.

Artificial Intelligence as an Aid in CBCT Airway Analysis: A Systematic Review.

BACKGROUND: The use of artificial intelligence (AI) in health sciences is becoming increasingly popular among doctors nowadays. This study evaluated the literature regarding the use of AI for CBCT airway analysis. To our knowledge, this is the first systematic review that examines the performance of artificial intelligence in CBCT airway analysis. METHODS: Electronic databases and the reference lists of the relevant research papers were searched for published and unpublished literature. Study selection, data extraction, and risk of bias evaluation were all carried out independently and twice. Finally, five articles were chosen. RESULTS: The results suggested a high correlation between the automatic and manual airway measurements indicating that the airway measurements may be automatically and accurately calculated from CBCT images. CONCLUSIONS: According to the present literature, automatic airway segmentation can be used for clinical purposes. The main key findings of this systematic review are that the automatic airway segmentation is accurate in the measurement of the airway and, at the same time, appears to be fast and easy to use. However, the present literature is really limited, and more studies in the future providing high-quality evidence are needed.

Mandibular Melanotic Neuroectodermal Tumor of Infancy: Interdisciplinary Treatment from 2 Months to 19 Years of Age.

Melanotic neuroectodermal tumor of infancy (MNTI) is a clinically distinctive, benign neoplasm of neural crest origin. The tumor develops usually in the anterior maxilla and rarely in the skull and mandible. This is a report of the interdisciplinary treatment of a rare case of MNTI occurring in the mandible. The patient was initially addressed for examination at the age of 2 months with a rapidly growing tumor of the mandible that had increased double in size in a week. A well-defined lesion in the left mandible shown on MRI and high urine vanillylmandelic acid (VMA) level determined the diagnosis. The complete interdisciplinary treatment included four interventions. Surgery with enucleation and curettage, performed as first intervention, at the age of 2 months. The second intervention lasted from age 7 to age 15 and included a first phase of Orthodontic treatment to monitor normal growth, followed by interceptive Orthodontic treatment and Prosthodontic intervention with interim dentures. The third intervention accomplished after competition of growth and included the pre-prosthetic surgery with an augmentation of the height of the edentulous atrophic mandible and placement of 4 implants. In the fourth intervention the permanent prosthodontic restoration supported by implants was applied.

Facial esthetic outcome of functional followed by fixed orthodontic treatment of class II division 1 patients.

OBJECTIVES: To assess the perceived facial changes in class II division 1, convex profile patients treated with functional followed by fixed orthodontic appliances. SUBJECTS AND METHODS: The study sample consisted of 36 pairs of pre- and post-treatment photographs (frontal and profile, at rest) of 12 patients treated with activator, 12 with twin-block, and 12 controls with normal profiles, treated without functional appliances. All photographs were presented in pairs to 10 orthodontists, 10 patients, 10 parents, and 10 laypersons. Visual analog scale (VAS) ratings of changes in facial appearance were assessed. RESULTS: The patient groups were similar in sex distributions, age, and treatment duration. The different rater groups showed strong to excellent agreement. There were no significant differences among treatment groups (F = 0.91; P = 0.526; Wilks lambda = 0.93), raters (F = 1.68; P = 0.054; Wilks lambda = 0.83), and when testing the combined effect of treatment and rater on the results (F = 0.72; P = 0.866; Wilks lambda = 0.85). The raters detected slightly more positive changes in the activator and twin-block groups, compared to the control group, regarding the lower face and the lips, but these findings did not reach significance. Furthermore, their magnitude hardly exceeded 1/20th of the total VAS length. LIMITATIONS: Retrospective study design. CONCLUSIONS: The perceived facial changes of convex profile patients treated with functional, followed by fixed orthodontic appliances, did not differ from those observed in normal profile patients, when full-face frontal and profile photos were simultaneously assessed. Consequently, professionals should be skeptical regarding the improvement of a patient's facial appearance when this treatment option is used.

Relation between soft tissue and skeletal changes after mandibular setback surgery: A systematic review and meta-analysis.

Accurate prediction of hard and soft tissue changes is essential in orthognathic surgery. The aim of the present study was to systematically investigate the relation between soft and hard tissue relocation after mandibular setback surgery. A systematic search was performed, correlation coefficients and ratios were retrieved from the eligible studies, and the risk of bias was assessed. The random effects method was used to combine data. The five eligible studies showed that sagittal changes in pogonion, point B, and incision inferius incisalis are highly correlated with respective soft tissue movements and exhibit ratios ranging from 0.915 to 1.051. Only two studies were classified as having a moderate risk of bias. Although the characteristics of the included data limit the formation of definite conclusions, the soft to hard tissue movement ratios produced constitute initial clinically relevant guidance. Further long-term standardized and well-conducted trials are needed.

Judgment of Nasolabial Esthetics in Cleft Lip and Palate Is Not Influenced by Overall Facial Attractiveness.

OBJECTIVE: To determine whether judgment of nasolabial esthetics in cleft lip and palate (CLP) is influenced by overall facial attractiveness. DESIGN: Experimental study. SETTING: University of Bern, Switzerland. SUBJECTS AND METHODS: Seventy-two fused images (36 of boys, 36 of girls) were constructed. Each image comprised (1) the nasolabial region of a treated child with complete unilateral CLP (UCLP) and (2) the external facial features, i.e., the face with masked nasolabial region, of a noncleft child. Photographs of the nasolabial region of six boys and six girls with UCLP representing a wide range of esthetic outcomes, i.e., from very good to very poor appearance, were randomly chosen from a sample of 60 consecutively treated patients in whom nasolabial esthetics had been rated in a previous study. Photographs of external facial features of six boys and six girls without UCLP with various esthetics were randomly selected from patients' files. Eight lay raters evaluated the fused images using a 100-mm visual analogue scale. Method reliability was assessed by reevaluation of fused images after >1 month. A regression model was used to analyze which elements of facial esthetics influenced the perception of nasolabial appearance. RESULTS: Method reliability was good. A regression analysis demonstrated that only the appearance of the nasolabial area affected the esthetic scores of fused images (coefficient = -11.44; P < .001; R(2) = 0.464). The appearance of the external facial features did not influence perceptions of fused images. CONCLUSION: Cropping facial images for assessment of nasolabial appearance in CLP seems unnecessary. Instead, esthetic evaluation can be performed on images of full faces.

Role of third molars in orthodontics.

The role of third molars in the oral cavity has been extensively studied over the years. Literature includes numerous diagnostic and treatment alternatives regarding the third molars. However, an issue that has not been discussed at the same level is their involvement in orthodontic therapy. The aim of this study is to present a review of the contemporary literature regarding the most broadly discussed aspects of the multifactorial role of third molars in orthodontics and which are of general dental interest too.

Interim prosthodontic management of surgery-induced dental agenesis: a clinical report of 8 years of treatment.

The prosthodontic management of a 7-year-old girl with induced dental agenesis is described. The mandibular posterior tooth germs had been removed during surgical excision of a melanotic neuroectodermal tumor of infancy, at the age of 2 months. The ongoing prosthodontic treatment, now in its eighth year, was implemented by regular follow-up of the operation outcome and by targeted orthodontic intervention. The treatment plan included the provision of four successive interim removable partial dentures. Care was taken to preserve the oral structures, adapt to the morphological changes, and satisfy the needs of the child. Due to the unfavorable biomechanical conditions, retention and stability problems were encountered. These were resolved by engaging the mechanism of neuromuscular adaptation through optimization of the shape of the denture base. For children and adolescents with extensive dental agenesis, prosthodontic management with interim removable dentures supports function, restores esthetics, and provides a solid basis for the definitive treatment.

A 13-year-old Caucasian boy with cleidocranial dysplasia: a case report.

BACKGROUND: Cleidocranial dysplasia (CCD) is a rare congenital autosomal dominant skeletal disorder. The disorder is caused by heterozygosity of mutations in human RUNX2, which is present on the short arm of chromosome 6p21. The incidence of CCD is one per million births. CCD appears spontaneously with no apparent genetic cause in approximately 40% of affected patients, and one in three patients has unaffected parents. The most prevalent features associated with CCD are aplastic or hypoplastic clavicles, supernumerary teeth, failed eruption of permanent teeth, and a hypoplastic maxilla. CASE PRESENTATION: A 13-year-old Caucasian boy presented with a chief complaint of delayed eruption of the permanent anterior teeth. The patient was subsequently diagnosed with CCD based on the clinical examination, panoramic X-ray, anterior-posterior and lateral cephalogram, and chest radiograph findings. The details of this case are herein reported because of the extremely low incidence of this disorder. CONCLUSIONS: CCD is of clinical importance in dentistry and medicine because it affects the bones and teeth and is characterized by many changes in skeletal patterning and growth. Particularly in dentistry, CCD is of great clinical significance because is associated with delayed ossification of the skull sutures, delayed exfoliation of the primary teeth, lack of permanent teeth eruption, multiple supernumerary teeth, and morphological abnormalities of the maxilla and mandible. Patients with CCD seek treatment mainly for dental problems. Knowledge of the pathogenesis, clinical characteristics, and diagnostic tools of CCD will enable clinicians to render the appropriate treatment to improve function and aesthetics. Early diagnosis of CCD is crucial for timely initiation of an appropriate treatment approach.

A severe open bite case treated with orthodontics and tongue reduction surgery: 13-year followup. A case report.

BACKGROUND: The management of open bite malocclusions creates controversy when treatment approach and long-term stability are considered. Tongue size, posture and habits have been associated as aetiologic and compounding factors. Reduction tongue surgery has therefore been advocated as an aid in treatment, especially when the open bite is accompanied by perceived macroglossia. AIM: The present article describes a clinical case of a 10-year-old girl who started treatment in the mixed dentition with an excessive open bite and speech defects. METHODS: A combination of orthodontics and a partial glossectomy was necessary to successfully address the open bite associated with an enlarged tongue. RESULTS: The need for orthognathic surgery treatment was eliminated and the patient was satisfied with the post-treatment aesthetics, function and speech. CONCLUSION: After 13 years of follow-up, a stable occlusion was maintained with only minor relapse.

Factors influencing the accuracy of cephalometric prediction of soft tissue profile changes following orthognathic surgery.

The cephalometric prediction of orthognathic treatment outcome is an important part of the surgical planning and the process of informed consent. The orthodontic and surgical changes must be described accurately prior to treatment in order to assess the treatment's feasibility, to optimize case management and to increase patient's understanding and acceptance of the recommended treatment. The aim of the present article was to investigate on the factors that could influence the accuracy of cephalometric prediction in planning orthognathic surgery. Review of the literature revealed that, besides factors directly related to the prediction method and its use, there exist a considerable number of factors which could affect significantly the accuracy of soft tissue response. These factors could be biological ones such as relapse, centre of mandibular rotation and individual variation in response to treatment and others such as gender, race, pre-operative soft tissue thickness and data bases for mean ratios of soft to hard tissue movement changes. Some of the factors affecting the accuracy of prediction of soft tissue response following orthognathic surgery are inevitable and there are others, difficult to control and predict. However, patients should be informed that predictions are only a guide, may not represent the actual result of the surgical outcome, and as such they should be implemented.

Macroglossia.

Macroglossia is defined as an enlarged tongue and it is usually clinically diagnosed. Pseudomacryglossia concerns a tongue that is of normal size but gives a false impression of being too large in relation to adjacent anatomical structures. The causes of macroglossia are numerous and this is why various classifications have been proposed for this condition. The consequences of macroglossia usually include a possible malfunction of the stomatognathic system, breathing and speech problems, increased mandible size, tooth spacing, diastema and other orthodontic abnormalities. The treatment of macroglossia depends on its aetiology and generally includes correcting the systemic disease underlying the increase in lingual mass, surgical treatment, radiotherapy and treatment of orthodontic abnormalities that might have been caused by the condition.

Cephalometric methods of prediction in orthognathic surgery.

Over the past decade the growing number of adult patients seeking for orthodontic treatment made orthognathic surgery popular. Surgical and orthodontic techniques have developed to the point where combined orthodontic and surgical treatment is now feasible to manage dentofacial deformity problems very satisfactorily. The prediction of orthognathic treatment outcome is an important part of orthognathic planning and the process of patient' inform consent. The predicted results must be presented to the patients prior to treatment in order to assess the treatment's feasibility, optimize case management and increase patient understanding and acceptance of the recommended treatment. Cephalometrics is a routine part of the diagnosis and treatment planning process and also allows the clinician to evaluate changes following orthognathic surgery. Traditionally cephalometry has been employed manually; nowadays computerized cephalometric systems are very popular. Cephalometric prediction in orthognathic surgery can be done manually or by computers, using several currently available software programs, alone or in combination with video images. Both manual and computerized cephalometric prediction methods are two-dimensional and cannot fully describe three-dimensional phenomena. Today, three-dimensional prediction methods are available, such as three-dimensional computerized tomography (3DCT), 3D magnetic resonance imaging (3DMRI) and surface scan/cone-beam CT. The aim of this article is to present and discuss the different methods of cephalometric prediction of the orthognathic surgery outcome.

Rapid palatal expander: an anchor unit for second molar distalization in Angle Class II treatment.

Distal movement of maxillary molars is a common approach for nonextraction treatment of Angle Class II patients. Because of known difficulties involving moving the maxillary first molars distally in the presence of second molars, this article describes how the distally directed force is applied immediately to the second molars. A rapid palatal expander can be used as a reliable unit to facilitate the distal movement of the second maxillary molars.

A severe reaction to ni-containing orthodontic appliances.

Exposure to nickel-containing orthodontic appliances may cause intra- or extraoral allergic reactions. Nickel is the most typical antigen implicated in causing allergic contact dermatitis, which is a Type IV delayed hypersensitivity immune response. This report presents an unusual reaction to nickel during the orthodontic treatment of an adult female patient. The patient had no previous history of allergy and had been wearing fixed metal upper appliances while in orthodontic treatment to assist the eruption of her impacted teeth. The adverse hypersensitivity reactions appeared only after the surgical exposure and included severe signs of eczematic and urticarial reactions of the face with redness, irritation, itching, eczema, soreness, fissuring, and desquamation as well as intraoral diffuse red zones. Diagnostic patch testing performed by the allergist revealed sensitization to nickel (++++ score). Treatment was achieved with nickel-free appliances.

Prevalence of nickel hypersensitivity in orthodontic patients: a meta-analysis.

INTRODUCTION: In spite of growing concern of routine mechanotherapy modalities in patients' health and recent regulations on nickel exposure, there has been no relevant meta-analysis. The aim of this study, therefore, was to investigate the effect of orthodontic therapy on the prevalence of nickel hypersensitivity and compare it with the prevalence in the general population. METHODS: Several electronic databases were searched. Hand-searching was also performed to identify additional relevant studies. Initially, 324 articles were retrieved. After applying specific inclusion criteria, 8 studies were eligible for the meta-analysis. Meta-analysis was performed with Comprehensive Meta-Analysis software (version 2.2.046, Biostat, Englewood, NJ). Evaluations of the validity of the included articles and of publication bias were also performed. RESULTS: A lack of high-validity longitudinal studies of the prevalence of nickel hypersensitivity in patients before and after orthodontic treatment and in appropriate controls was noted. From the studies retrieved, no statistically significant difference between the odds for a positive patch-test result before orthodontic treatment and after the placement of the appliances was observed. Orthodontic patients with no cutaneous piercing or with skin pierced have no statistically significant differences of nickel hypersensitivity after treatment compared with the general population. CONCLUSIONS: Orthodontic treatment is not associated with an increase in the prevalence of nickel hypersensitivity unless subjects have a history of cutaneous piercing. High-validity studies are needed to produce strong evidence to further support the results of this meta-analysis.