Association between psychological traits and occlusal tactile acuity of healthy individuals.

OBJECTIVES: Tactile acuity is a somatosensory measure of the extent to which humans can discern tactile stimuli. It is influenced by how peripheral signals are processed centrally. In the oral cavity, Occlusal Tactile Acuity (OTA) is the ability to perceive minimal thicknesses between antagonist teeth. The aim of the current study was to assess the association between psychological traits and OTA of otherwise healthy individuals. METHODS: Sixty-three volunteers (32 males; mean age ± SD: 24.6 ± 2.7 years) participated in this study. Somatosensory amplification, anxiety, depression, physical symptoms and pain catastrophizing were scored using questionnaires, and subgroups of severity were created per variable based on cut-offs. OTA was measured using 9 aluminium foils with thickness (ranging from 8 to 72 µm) and one sham test (without foil). Each thickness was tested 10 times in random order, the participants were instructed to report whether they felt the foil between their molars and the mean percentage of correct answers was computed. A linear mixed model was used with OTA as a dependent variable and psychological domain as an independent variable. RESULTS: Significantly different OTA was observed among the anxiety subgroups (p = .003), supporting a decreased perception of thicknesses 24 and 32 µm (p = .018 and p < .001, respectively) in participants with moderate/severe anxiety compared to those with no/mild anxiety. Significantly different OTA was also observed among the pain catastrophizing subgroups (p = .008), showing decreased perception of thicknesses 32 and 40 µm (p < .001 and p = .007, respectively) in severe catastrophizing levels, compared to no/mild catastrophizing levels. No significant differences were observed for the other variables. CONCLUSIONS: Healthy adults with increased anxiety or pain catastrophizing levels show decreased interdental acuity as compared to participants with minor or no psychological impairment.

Patient safety in orthodontic care: a scoping literature review with proposal for terminology and future research agenda.

BACKGROUND: Knowledge about patient safety in orthodontics is scarce. Lack of standardisation and a common terminology hinders research and limits our understanding of the discipline. This study aims to 1) summarise current knowledge about patient safety incidents (PSI) in orthodontic care by conducting a systematic literature search, 2) propose a new standardisation of PSI terminology and 3) propose a future research agenda on patient safety in the field of orthodontics. METHODS: A systematic literature search was performed in the main online sources of PubMed, Web of Science, Scopus and OpenGrey from their inception to 1 July 2023. Inclusion criteria were based on the World Health Organization´s (WHO) research cycle on patient safety. Studies providing information about the cycle's steps related to orthodontics were included. Study selection and data extraction were performed by two of the authors. RESULTS: A total of 3,923 articles were retrieved. After review of titles and abstracts, 41 articles were selected for full-text review and 25 articles were eligible for inclusion. Seven provided information on the WHO's research cycle step 1 ("measuring harm"), twenty-one on "understanding causes" (step 2) and twelve on "identifying solutions" (step 3). No study provided information on Steps 4 and 5 ("evaluating impact" or "translating evidence into safer care"). CONCLUSION: Current evidence on patient safety in orthodontics is scarce due to a lack of standardised reporting and probably also under-reporting of PSIs. Current literature on orthodontic patient safety deals primarily with "measuring harms" and "understanding causes of patient safety", whereas less attention has been devoted to initiatives "identifying solutions", "evaluating impact" and "translating evidence into safer care". The present project holds a proposal for a new categorisation, terminology and future research agenda that may serve as a framework to support future research and clinical initiatives to improve patient safety in orthodontic care. REGISTRATION: PROSPERO (CRD42022371982).

Management of temporomandibular joint arthritis in children and adolescents: An introduction for orthodontists.

Juvenile idiopathic arthritis (JIA) is the most common inflammatory rheumatic disease of childhood. JIA can affect any joint and the temporomandibular joint (TMJ) is one of the joints most frequently involved. TMJ arthritis impacts mandibular growth and development and can result in skeletal deformity (convex profile and facial asymmetry), and malocclusion. Furthermore, when TMJs are affected, patients may present with pain at joint and masticatory muscles and dysfunction with crepitus and limited jaw movement. This review aims to describe the role of orthodontists in the management of patients with JIA and TMJ involvement. This article is an overview of evidence for the diagnosis and treatment of patients with JIA and TMJ involvement. Screening for the orofacial manifestation of JIA is important for orthodontists to identify TMJ involvement and related dentofacial deformity. The treatment protocol of JIA with TMJ involvement requires an interdisciplinary collaboration including orthopaedic/orthodontic treatment and surgical interventions for the management of growth disturbances. Orthodontists are also involved in the management of orofacial signs and symptoms; behavioural therapy, physiotherapy and occlusal splints are the suggested treatments. Patients with TMJ arthritis require specific expertise from an interdisciplinary team with members knowledgeable in JIA care. Since disorders of mandibular growth often appear during childhood, the orthodontist could be the first clinician to see the patient and can play a crucial role in the diagnosis and management of JIA patients with TMJ involvement.

Longitudinal trends in temporomandibular joint disorder symptoms, the impact of malocclusion and orthodontic treatment: A 20-year prospective study.

BACKGROUND: Studies on the association between malocclusion and temporomandibular joint disorder (TMD) have reported conflicting results. OBJECTIVES: To determine the impact of malocclusion and orthodontic treatment on symptoms of TMD. METHODS: At 12 years, 195 subjects fulfilled a questionnaire regarding TMD symptoms and participated in an oral examination including preparation of dental casts. The study was repeated at ages 15 and 32. The occlusions were assessed by applying the Peer Assessment Rating (PAR) Index. Associations between the changes in PAR scores and TMD symptoms were analysed with the chi-square test. A multivariable logistic regression was used to calculate the odds ratios (OR) and 95% confidence intervals (CI) of TMD symptoms at 32 years predicted by sex, occlusal traits and orthodontic treatment history. RESULTS: One in three subjects (29%) was orthodontically treated. Sex was associated with more self-reported headaches by females at 32 years (OR 2.4, 95% CI 1.05-5.4; p = .038). At all time points, any crossbite was significantly associated with greater odds for self-reported temporomandibular joint (TMJ) sounds at 32 years (OR 3.5, 95% CI 1.1-11.6; p = .037). More specifically, association occurred with posterior crossbite (OR 3.3, 95% CI 1.1-9.9; p = .030). At 12 and 15 years, boys whose PAR score increased were more likely to develop TMD symptoms (p = .039). Orthodontic treatment had no impact on the number of symptoms. CONCLUSIONS: Presence of crossbite may increase the risk of self-reported TMJ sounds. Also, longitudinal changes in occlusion may have an association with TMD symptoms while orthodontic treatment is not associated with the number of symptoms.

Diagnostic criteria for temporomandibular disorders-INfORM recommendations: Comprehensive and short-form adaptations for children.

BACKGROUND: The Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) are used worldwide in adults. Until now, no adaptation for use in children has been proposed. OBJECTIVE: The aim of this study was to present comprehensive and short-form adaptations of Axis I and Axis II of the DC/TMD for adults that are appropriate for use with children in clinical and research settings. METHODS: Global Delphi studies with experts in TMDs and in pain psychology identified ways of adapting the DC/TMD for children. RESULTS: The proposed adaptation is suitable for children aged 6-9 years. Proposed changes in Axis I include (i) adapting the language of the Demographics and the Symptom Questionnaires to be developmentally appropriate for children, (ii) adding a general health questionnaire for children and one for their parents, (iii) replacing the TMD Pain Screener with the 3Q/TMD questionnaire and (iv) modifying the clinical examination protocol. Proposed changes in Axis II include (i) for the Graded Chronic Pain Scale, to be developmentally appropriate for children, (ii) adding anxiety and depression assessments that have been validated in children and (iii) adding three constructs (stress, catastrophising and sleep disorders) to assess psychosocial functioning in children. CONCLUSION: The recommended DC/TMD, including Axis I and Axis II, for children aged 6-9 years, is appropriate for use in clinical and research settings. This adapted the first version for children includes changes in Axis I and Axis II changes requiring reliability and validity testing in international settings. Official translations to different languages according to INfORM requirements will enable a worldwide dissemination and implementation.

Diagnostic criteria for temporomandibular disorders-INfORM recommendations: Comprehensive and short-form adaptations for adolescents.

BACKGROUND: The Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) for use in adults is in use worldwide. Until now, no version of this instrument for use in adolescents has been proposed. OBJECTIVE: To present comprehensive and short-form adaptations of the adult version of DC/TMD that are appropriate for use with adolescents in clinical and research settings. METHODS: International experts in TMDs and experts in pain psychology participated in a Delphi process to identify ways of adapting the DC/TMD protocol for physical and psychosocial assessment of adolescents. RESULTS: The proposed adaptation defines adolescence as ages 10-19 years. Changes in the physical diagnosis (Axis I) include (i) adapting the language of the Demographics and the Symptom Questionnaires to be developmentally appropriate for adolescents, (ii) adding two general health questionnaires, one for the adolescent patient and one for their caregivers and (iii) replacing the TMD Pain Screener with the 3Q/TMD questionnaire. Changes in the psychosocial assessment (Axis II) include (i) adapting the language of the Graded Chronic Pain Scale to be developmentally appropriate for adolescents, (ii) adding anxiety and depression assessment that have been validated for adolescents and (iii) adding three constructs (stress, catastrophizing and sleep disorders) to assess psychosocial functioning in adolescents. CONCLUSION: The recommended DC/TMD, including Axis I and Axis II for adolescents, is appropriate to use in clinical and research settings. This adapted first version for adolescents includes changes in Axis I and Axis II requiring reliability and validity testing in international settings. Official translations of the comprehensive and short-form to different languages according to INfORM requirements will enable a worldwide dissemination and implementation.

Diagnostic criteria for temporomandibular disorders in children and adolescents: An international Delphi study-Part 2-Development of Axis II.

BACKGROUND: Unlike the psychosocial assessment established for adults in the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD), a standardised psychosocial assessment for children and adolescents with TMD complaints has not yet been established. OBJECTIVES: To develop a new standardised instrument set to assess the psychosocial functioning in children and adolescents by adapting the psychosocial status and pain-related disability (Axis II) of the adult DC/TMD and by including new instruments. METHODS: A modified Delphi method was used to survey 23 international TMD experts and four international experts in pain-related psychological factors for consensus regarding assessment tools for psychosocial functioning and pain-related disability in children and adolescents. The TMD experts reviewed 29 Axis II statements at round 1, 13 at round 2 and 2 at round 3. Agreement was set at 80% for first-round consensus level and 70% for each of the second and third rounds. The psychological experts completed a complementary Delphi survey to reach a consensus on tools to use to assess more complex psychological domains in children and adolescents. For the psychological experts, the first round included 10 open-ended questions on preferred screening tools for depression, anxiety, catastrophising, sleep problems and stress in children (ages 6-9 years old) and adolescents (ages 10-19 years old) as well as on other domains suggested for investigation. In the second round, the psychological experts received a 9-item questionnaire to prioritise the suggested instruments from most to least recommended. RESULTS: The TMD experts, after three Delphi rounds, reached consensus on the changes of DC/TMD to create a form to evaluate Axis II in children and adolescents with TMD complaints. The psychological experts added tools to assess depression and anxiety, sleep disorders, catastrophising, stress and resilience. CONCLUSION: Through international expert consensus, this study adapted Axis II of the adult DC/TMD to assess psychosocial functioning and pain-related disability in children and adolescents. The adapted Axis II protocols will be validated in the target populations.

Three-dimensional soft tissue changes in orthodontic extraction and non-extraction patients: A prospective study.

OBJECTIVES: To assess the soft tissue changes in orthodontic extraction and non-extraction patients on 3D stereophotogrammetric images. SETTING AND SAMPLE: 23 extraction (22.2 ± 9.2 years) and 23 non-extraction (20.3 ± 11.1 years) consecutive patients were enrolled at the Sections of Orthodontics at Aarhus University and at University of Naples Federico II. METHODS: All patients had a first 3D image taken after bonding of brackets on the upper incisors (T0), and a second 3D image (T1) after space closure in the extraction group or at insertion of the first SS or TMA rectangular wire in the non-extraction group. The 3D images were captured with 3dMDFace System and analysed with 3dMDVultus Software. After placing 19 landmarks, 15 measurements were obtained. Intragroup changes were analysed with paired t-test and intergroup changes with unpaired t-test (P < .05). RESULTS: Superimpositions of the 3D images at T0 and T1 visualized with colour-coded maps showed that soft tissue changes primarily happened in the perioral area in both groups. The Nasolabial angle increased significantly in the extraction group (3°± 4.1, P = .002), while it decreased in the non-extraction group (-1.5°± 5.5°, P = .002). There was a significant difference between the two groups (4.4°, P = .004). CONCLUSIONS: 3D comparison of the soft tissues in the extraction and non-extraction groups showed statistically significant, but clinically limited differences in the perioral area. The Nasolabial angle was significantly larger at T1 in the extraction group compared with the non-extraction group.

Effects of acute pain and strain of the periodontium due to orthodontic separation on the occlusal tactile acuity of healthy individuals.

OBJECTIVES: The aim of this study was to assess whether pain and strain of the periodontal ligament (PDL), induced by orthodontic separation, alter the somatosensory ability to perceive small thicknesses between occluding teeth (occlusal tactile acuity, OTA). METHODS: The OTA was tested at baseline (T0), using 9 aluminum foils (range 8-72 µm), randomly placed between the molar teeth, and 1 sham test (without foil), asking the participants whether they felt the foil between their teeth. Afterwards, orthodontic separators were placed, and subjects were randomly assigned to one of the two experimental groups: Group Pain (GP: 18 males; 14 females mean age 25.22 ± 2.28 years) had separators removed after 24 h; Group Strain (GS: 14 males; 17 females, mean age 24.03 ± 3.06 years) had separators removed after 7 days. The OTA measurement was repeated in both groups immediately after orthodontic separators removal (T1). A within-group comparison (T1 vs T0) was performed for each testing thickness (ANOVA for repeated measurements, with Bonferroni correction for multiple testing) (p < 0.005). RESULTS: GP showed statistically significant reduction of the OTA at T1, as compared to T0, for the thicknesses 24 µm (p = 0.004) and 32 µm (p = 0.001). No significant reduction was observed in GS (all p > 0.005). CONCLUSIONS: Acute periodontal pain tends to disturb the tactile ability of the teeth, while strain of the PDL in absence of painful sensation determines a return to OTA baseline values. CLINICAL RELEVANCE: The reduction of OTA might explain the uncomfortable occlusal sensation referred by patients during acute periodontal pain.

Association between waking-state oral behaviours, according to the oral behaviors checklist, and TMD subgroups.

OBJECTIVES: To assess the association between waking-state oral behaviours and temporomandibular disorder (TMD) subgroups and to develop new scoring methods for the Oral Behavior Checklist (OBC). METHODS: Patients with any TMD diagnosis, according to the diagnostic criteria for TMD (DC/TMD), were divided into subgroups: 'Dysfunctional-TMD' (n = 70), only mechanical dysfunction; 'Painful-TMD' (n = 204), only myalgia, arthralgia or both; and 'Painful-Dysfunctional TMD' (n = 95), combined pain and dysfunction. A group of individuals without TMD, 'Non-TMD' (n = 374), was used for testing associations. Participants completed the OBC. An exploratory factor analysis, followed by a confirmatory factor analysis of the OBC responses, identified 2 major factors, named non-functional activities (NFA) and functional activities (FA). Component total scores were computed. Differences among subgroups for OBC-MS (mean score) and NFA and FA factor scores were estimated using one-way ANOVA and Tukey post hoc tests. Significance was set at p < .05. RESULTS: The OBC-MS in Non-TMD, Painful-TMD and Painful-Dysfunctional TMD subgroups was higher than in the Dysfunctional-TMD subgroup (p ≤ .001). NFA in Painful-TMD and Painful-Dysfunctional TMD subgroups were higher than in the Non-TMD group (p < .05); NFA in the Dysfunctional-TMD subgroup were lower than in the Painful-TMD subgroup (p = .034). In contrast, FA in Painful-TMD, Dysfunctional-TMD and Painful-Dysfunctional TMD subgroups were lower than in the Non-TMD group (p < .0001). CONCLUSIONS: A new scoring method for the OBC results in item reduction and creation of meaningful subscales for functional and non-functional behaviours, which are differentially associated with painful and dysfunctional TMDs. This may help clinicians to better tailor treatment for the management of subtypes of TMD patients.

Pseudo Hemifacial Microsomia With Condylar-Coronoid Collapse: New Therapeutic Approach in Growing Patients.

The purpose of this study is to describe the management of 2 dimorphic patients affected by Hemimandibular Hypoplasia with Condylar-Coronoid Collapse (HH-CCC), also called Pseudo Hemifacial Microsomia, where the orthopedic treatment gave an excellent long-term follow-up. The patients were a 7-year-old female and a 6-year-old male with a HH-CCC on the left side, an asymmetrical face with chin deviation, class II dental malocclusion and canting of the occlusal plane. An X-ray evaluation and clinical observation confirmed the unilateral mandibular deficiency and the collapse of the condyle on the coronoid process on the affected side. The treatment plan consisted of the use of an asymmetrical functional appliance with a vertical screw. The appliance was gradually activated on the vertical plane on one side by a screw incorporated on an acrylic plate. It was used for 22 hours/day, including sleep time but not during meals. This treatment improved the patient' s facial appearance. HH-CCC showed a positive response to functional therapy.

"Pressure pain threshold over masticatory muscles and temporomandibular joint in patients with juvenile idiopathic arthritis".

BACKGROUND: Juvenile idiopathic arthritis (JIA) is an autoimmune, chronic, inflammatory joint disease, affecting children and adolescents. Patients with JIA may have pain and fatigue in muscles. There are not studies evaluating the pressure pain thresholds (PPTs) of both masticatory muscles and temporomandibular joint (TMJ) in patients with JIA. OBJECTIVE: This study aimed to investigate PPTs of masticatory muscles and TMJ in subjects with JIA. METHODS: Fifty-one JIA patients and fifty-two healthy subjects were recruited. JIA group was assessed for with a standardised clinical examination for temporomandibular disorders. In all subjects, the PPT was evaluated in the following sites: anterior temporalis (AT) and masseter (MM) muscles, TMJ and thenar (TH) eminence. Comparisons between groups were assessed with unpaired t test and ANOVA (P < .05). RESULTS: Pressure pain thresholds were significantly lower among JIA patients compared with controls (P < .001) for all analysed sites. The presence of TMJ pain at palpation was significantly associated with a lower PPT at TMJ (P = .031). CONCLUSIONS: Patients with JIA have generally lowered pain threshold to mechanical stimulus, which suggests an effect of JIA on nocicepton-modulating processes.

Short-term effects of the Sander bite-jumping appliance on the pharyngeal airways in subjects with skeletal Class II malocclusion: A retrospective case-control study.

BACKGROUND: Skeletal Class II subjects present often a retruded mandible that might increase the probability of breathing disorders. OBJECTIVE: To evaluate the effects of functional treatment by means of the Sander bite-jumping appliance (BJA) on the upper airways of growing subjects. METHODS: Thirty-four subjects (21 males, 13 females; mean age 11.1 ± 1.2 years) with skeletal Class II malocclusion due to mandibular retrusion were treated with the Sander BJA (BJA group). The control group consisted of thirty-four untreated subjects with skeletal Class II malocclusion (25 males, 9 females; 10.4 ± 1.2 years; CTR group). The effect of the Sander BJA appliance on the airway dimensions was evaluated by comparing lateral cephalograms recorded before (T0) and after (T1) the period of observation/treatment. Within- and between-group comparisons were statistically evaluated according to the distribution of the data (P < .05). RESULTS: The oropharyngeal region (ph_pph) increased in the BJA group (1.8 ± 3.2; P = .001) but the difference respect to the CTR group was not statistically significant (0.73 ± 4.0; P = .314; P = .077). The tongue height (th) increased in the BJA group (2.8 ± 3.7; P < .001), and this increase was statistically significant respect to the CTR group (0.6 ± 4.7; P = .461; P = .038). In the BJA, the Ans_Pns_P angle showed a statistically significant decrease (-3.8 ± 7.8; P = .007) compared to the CTR group (-0.1 ± 5.4; P = .705; P = .026). CONCLUSIONS: The airway dimensions increased for both control subjects and Class II patients treated with Sander BJA due to physiological growth. The Sander BJA induced a statistically significant change in the tongue and soft palate position, but the clinically relevant of these changes is questionable.

Evaluation of masticatory muscle activity in patients with unilateral posterior crossbite before and after rapid maxillary expansion.

Objectives: The relationship between unilateral posterior crossbite (UPCB) and the possible asymmetric activation of the jaw muscles in children is still under debate. This study aimed at evaluating the jaw muscle activity of children with UPCB before and after rapid maxillary expansion (RME) by means of surface electromyography and a standardized sampling protocol. Subjects and methods: Twenty-nine children with UPCB (UPCB-group, mean age 9.6 ± 1.6 years) and 40 UPCB-free controls (Control-group, 10.5 ± 1.1) were recruited. The activity of the left and right anterior temporalis (AT) and superficial masseter muscles (MM) was recorded during maximum voluntary clenching and a chewing task (T0). In the UPCB-group, data were collected, also, after the correction of the UPCB with RME (T1) and 6 months later (T2), without any further treatment. Electromyographic indices comparing the activity of paired muscle were computed via software to estimate the extent of asymmetric AT and MM activity. Paired and unpaired t-test or Wilcoxon-signed rank and Mann-Whitney U test, ANOVA or Friedman test and chi-squared test were used in the statistical analysis. Results: Both groups presented with asymmetric activity of the muscles, which did not differ between groups (T0, all P > 0.05). The treatment determined a decrease in muscular activity (T1, P = 0.040), and a more asymmetric pattern of muscle activation during chewing (T1, P = 0.040), which returned similar to baseline values at T2 (all P > 0.05). Conclusions: UPCB does not contribute to an asymmetric activation of AT and MM during functional tasks. The treatment of UPCB by RME did not determine a more symmetric activity of the assessed muscles.

Frequency of daytime tooth clenching episodes in individuals affected by masticatory muscle pain and pain-free controls during standardized ability tasks.

OBJECTIVES: Tooth clenching has been suggested to be related to temporomandibular pain. However, the electromyographic characteristics of daytime clenching episodes have been minimally investigated. This study aimed to analyze the frequency, amplitude, and duration of daytime clenching episodes in patients with masticatory muscle pain and pain-free individuals. METHODS: Fifteen women with masticatory muscles myalgia (MP group, mean ± SD age = 26.4 ± 7.6 years) matched for age to 18 pain-free women (CTR group, mean ± SD age = 25.3 ± 2.8 years) were submitted to three different ability tasks (filling out questionnaires for 40 min, reading for 20 min, and playing a videogame for 20 min). The electromyographic activity periods (AP) of the right masseter greater than 10 % (AP10), 20 % (AP20), and 30 % (AP30) of the maximum voluntary contraction were analyzed. RESULTS: The mean frequencies of AP10, AP20, and AP30 were greater in MP than in CTR individuals (all p < 0.05). The mean duration of AP10 was higher in MP group than CTR group only while filling out the questionnaires (p = 0.0033). CTR group had an increased frequency and duration of AP10 while playing the videogame than while reading a magazine. The ability tasks did not affect the muscle activity in the MP group. CONCLUSIONS: Individuals with masticatory muscle pain have an increased frequency of both high and low-intense daytime clenching episodes. The type of ability task affects the frequency and the duration of clenching episodes only in pain-free individuals. CLINICAL RELEVANCE: Clinicians should recognize that the frequency and intensity of daytime clenching are noticeably increased in individuals with masticatory muscle pain in order to better tailor treatment.

Dentoskeletal effects of oral appliance wear in obstructive sleep apnoea and snoring patients.

OBJECTIVES: To evaluate the dentoskeletal changes associated with long-term and continuous mandibular advancement device (MAD) use in sleep-related breathing disorder patients. METHODS: Cephalometric measurements and three-dimensional model analysis were performed at baseline and after 3.5 ± 1.1 years in 20 snoring and obstructive sleep apnoea patients treated with the Silensor® appliance. Intra-group differences were compared using paired t-test or Wilcoxon signed-rank test. A regression analysis was performed for variables that showed a statistically significant difference between time points to evaluate the influence of treatment time and patient's initial characteristics on their variations. The statistical significance was set at P < 0.05. RESULTS: At cephalometric assessment, the maxilla revealed a significant decrease in horizontal position (SNA: -0.4 ± 0.72 degree, P = 0.021) and a significant retroclination of the upper incisor (-1.59 ± 1.07 degree, P < 0.001), while the mandible displayed a significant downward rotation (0.88 ± 1.28 degree, P = 0.006) and a proclination of the lower incisor (2.27 ± 1.38 degree, P < 0.001). Model analysis showed a decrease in upper total space discrepancy (-0.66 ± 0.72 mm, P < 0.002), overjet (OJ; -0.34 ± 0.47 mm, P < 0.011), and overbite (-0.4 ± 0.52 mm, P < 0.004). In the regression analysis, treatment time influenced the lower incisor inclination (Beta = -0.713, P = 0.018) and OJ (Beta = -0.218, P = 0.018); patients' initial characteristics had an effect on OJ (Beta = -0.195, P = 0.011). LIMITATIONS: A larger sample size could increase the generalizability of the findings. CONCLUSION: MAD wear after a mean of 3.5 years determines statistically significant but clinically irrelevant dentoskeletal changes. Their potential occurrence should be thoroughly discussed with patients; regular follow-up visits by a specialist experienced in dental sleep medicine are also mandatory during treatment in addition to polysomnographic examinations.

Effect of somatosensory amplification and trait anxiety on experimentally induced orthodontic pain.

The perception of pain varies considerably across individuals and is affected by psychological traits. This study aimed to investigate the combined effects of somatosensory amplification and trait anxiety on orthodontic pain. Five-hundred and five adults completed the State Trait Anxiety Inventory (STAI) and the Somatosensory Amplification Scale (SSAS). Individuals with combined STAI and SSAS scores below the 20th percentile (LASA group: five men and 12 women; mean age ± SD = 22.4 ± 1.3 yr) or above the 80th percentile (HASA group: 13 men and seven women; mean age ± SD = 23.7 ± 1.0 yr) were selected and filled in the Oral Behaviors Checklist (OBC). Orthodontic separators were placed for 5 d in order to induce experimental pain. Visual analog scales (VAS) were administered to collect ratings for occlusal discomfort, pain, and perceived stress. Pressure pain thresholds (PPT) were measured. A mixed regression model was used to evaluate pain and discomfort ratings over the 5-d duration of the study. At baseline, the LASA group had statistically significantly higher PPT values for the masseter muscle than did the HASA group. During the experimental procedure, the HASA group had statistically significantly higher discomfort and pain. A significant difference in pain ratings during the 5 d of the study was found for subjects in the HASA group. Higher OBC values were statistically significantly positively associated with pain. Somatosensory amplification and trait anxiety substantially affect experimentally induced orthodontic pain.

Reproducibility of the assessment of the Fränkel manoeuvre for the evaluation of sagittal skeletal discrepancies in Class II individuals.

OBJECTIVES: The Fränkel manoeuvre is a procedure by which the mandible of Class II individuals is postured forward in dental Class I relationship. The evaluation of the resulting facial profile provides information concerning the components determining the sagittal discrepancy. Data concerning the reproducibility of its assessment are not available. This study aimed to evaluate the intra-observer and inter-observer reproducibility of the assessment of the manoeuvre and to assess whether the amount of clinical experience affects its reproducibility. METHODS: Two lateral photographs, one in centric occlusion, and the other with the mandible postured forward (Fränkel manoeuvre) of 100 Angle Class II individuals aged between 9 and 13 years were evaluated by six orthodontists (T0). Each examiner was asked whether the facial profile worsen or not with the manoeuvre after being trained by an expert orthodontist. The test was repeated after 2 weeks interval (T1). Intra-observer and inter-observer agreement were evaluated by computing the Cohen's K. RESULTS: The agreement (K values) between observations (T0 versus T1) for each examiner ranged from 0.49 to 0.72. The overall agreement was 0.65 [95% confidence interval (CI) = 0.54-0.75]. The agreement in the group with less clinical experience was 0.61 (95% CI = 0.46-0.76), while it was 0.68 (95% CI = 0.53-0.83) in the more experienced group. The amount of clinical experience did not affect intra-observer agreement (P = 0.50). The overall agreement between the examiners and the trainer was 0.74 (95% CI = 0.65-0.83) and 0.73 (95% CI = 0.64-0.83) at T0 and T1 respectively. CONCLUSION: The assessment of the Fränkel manoeuvre is reproducible and it is not influenced by the amount of clinical experience.