The effect of culture on pain sensitivity

Cross-cultural differences in pain sensitivity have been identified in pain-free subjects as well as in chronic pain patients. The aim was to assess the impact of culture on psychophysical measures using mechanical and electrical stimuli in patients with temporomandibular disorder (TMD) pain and pain-free matched controls in three cultures. This case-control study compared 122 female cases of chronic TMD pain (39 Saudis, 41 Swedes and 42 Italians) with equal numbers of age- and gender-matched TMD-free controls. Pressure pain threshold (PPT) and tolerance (PPTo) were measured over one hand and two masticatory muscles. Electrical perception threshold and electrical pain threshold (EPT) and tolerance (EPTo) were recorded between the thumb and index fingers. Italian females reported significantly lower PPT in the masseter muscle than other cultures (P < 0.001) and in the temporalis muscle than Saudis (P = 0.003). Swedes reported significantly higher PPT in the thenar muscle than other cultures (P = 0.017). Italians reported significantly lower PPTo in all muscles than Swedes (P ≤ 0.006) and in the masseter muscle than Saudis (P < 0.001). Italians reported significantly lower EPTo than other cultures (P = 0.01). Temporomandibular disorder cases, compared to TMD-free controls, reported lower PPT and PPTo in all the three muscles (P < 0.001). This study found cultural differences between groups in the PPT, PPTo and EPTo. Overall, Italian females reported the highest sensitivity to both mechanical and electrical stimulation, while Swedes reported the lowest sensitivity. Mechanical pain thresholds differed more across cultures than did electrical pain thresholds. Cultural factors may influence response to type of pain test

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

Late-Developing Supernumerary Premolars: Analysis of Different Therapeutic Approaches

This case series describes the different potential approaches to late-developing supernumerary premolars (LDSP). LDSP are supernumerary teeth (ST) formed after the eruption of the permanent dentition; usually they develop in the premolar region of the upper and lower jaw. The choice to extract or to monitor the LDSP depends on many factors and has to be carefully planned due to the several risks that either the monitoring or the extraction could provoke. These four cases of LDSP showed different treatment plan alternatives derived from a scrupulous assessment of the clinical and radiographic information

Skeletal and dental effects of Class III orthopaedic treatment: a systematic review and meta-analysis

To summarise the skeletal, dental and soft tissue effects of orthopaedic treatment on growing skeletal class III patients compared with a concurrent untreated similar control group and to evaluate whether the design of the primary studies may affect the results. A literature search was performed up to the end of February 2016. No restrictions were applied concerning language and appliances. Once the quality score was assessed, a meta-analysis was performed for the appliances used in more than three studies. A moderator analysis for study design was performed. The level of evidence was evaluated by means of the Grades of Recommendation, Assessment, Development and Evaluation (GRADE) tool. The search resulted in 21 papers. The quality of most of the studies was medium. Each study reported skeletal sagittal improvement and overjet correction. Fourteen studies reported a significant increase in lower facial height. Follow-up data showed slight relapses in about 15% of patients. Meta-analyses were performed for the facemask and chin cup. The two appliances were efficient for correcting the sagittal discrepancy, increasing the divergence. In the analysis for study design, the retrospective studies showed a more efficient appliance than RCTs for 6 of 13 variables. The level of evidence was between very low and moderate. There is very low to low evidence that orthopaedic treatment is effective in the correction of Class III skeletal discrepancies and moderate evidence for the correction of the overjet. A common side effect is mandibular clockwise rotation in older subjects

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

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

Dental and skeletal effects of palatal expansion techniques: a systematic review of the current evidence from systematic reviews and meta-analyses

The aim was to assess the quality and to summarise the findings of the Systematic Reviews (SRs) and Meta-Analyses (MAs) on the dental and skeletal effects of maxillary expansion. Electronic and manual searches have been independently conducted by two investigators, up to February 2015. SRs and MAs on the dentoalveolar and skeletal effects of fixed expanders were included. The methodological quality was assessed using the AMSTAR (A Measurement Tool to Assess Systematic Reviews). The design of the primary studies included in each SR/MA was assessed with the LRD (Level of Research Design scoring). The evidence for each outcome was rated applying a pre-determined scale. Twelve SRs/MAs were included. The AMSTAR scores ranged from 4 to 10. Two SRs/MAs included only RCTs. The current findings from SRs/MAs support with high evidence a significant increase in the short-term of maxillary dentoalveolar transversal dimensions after Rapid Maxillary Expansion (RME). The same effect is reported with moderate evidence after Slow Maxillary Expansion (SME). However, there is moderate evidence of a non-significant difference between the two expansion modalities concerning the short-term dentoalveolar effects. With both RME and SME, significant increase of skeletal transversal dimension in the short-term is reported, and the skeletal expansion is always smaller than the dentoalveolar. Even though dental relapse to some extent is present, long-term results of the dentoalveolar effects show an increase of the transversal dimension, supported by moderate evidence for RME and low evidence for SME. Skeletal long-term effects are reported only with RME, supported by very low evidence

Effectiveness of Manual Therapy and Therapeutic Exercise for Temporomandibular Disorders: Systematic Review and Meta-Analysis

Manual therapy (MT) and exercise have been extensively used to treat people with musculoskeletal conditions such as temporomandibular disorders (TMD). The evidence regarding their effectiveness provided by early systematic reviews is outdated

Does clinical experience affect the reproducibility of cervical vertebrae maturation method?

To assess interobserver and intraobserver reproducibility of the cervical vertebrae maturation method (CVMM) among three panels of judges with different levels of orthodontic experience (OE)

In vitro biocompatibility of nickel-titanium esthetic orthodontic archwires

Objective: To investigate the cytotoxicity of nickel-titanium (NiTi) esthetic orthodontic archwires with different surface coatings. Materials and Methods: Three fully coated, tooth-colored NiTi wires (BioCosmetic, Titanol Cosmetic, EverWhite), two ion-implanted wires (TMA Purple, Sentalloy High Aesthetic), five uncoated NiTi wires (BioStarter, BioTorque, Titanol Superelastic, Memory Wire Superelastic, and Sentalloy), one b-titanium wire (TMA), and one stainless steel wire (Stainless Steel) were considered for this study. The wire samples were placed at 37uC in airtight test tubes containing Dulbecco’s Modified Eagle’s Medium (0.1 mg/mL) for 1, 7, 14, and 30 days. The cell viability of human gingival fibroblasts (HGFs) cultured with this medium was assessed by the 3-(4,5- dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Data were analyzed by a twoway analysis of variance (a 5 .05). Results: The highest cytotoxic effect was reached on day 30 for all samples. The archwires exhibited a cytotoxicity on HGFs ranging from “none” to “slight,” with the exception of the BioTorque, which resulted in moderate cytotoxicity on day 30. Significant differences were found between esthetic archwires and their uncoated pairs only for BioCosmetic (P 5 .001) and EverWhite (P , .001). Conclusions: Under the experimental conditions, all of the NiTi esthetic archwires resulted in slight cytotoxicity, as did the respective uncoated wires. For this reason their clinical use may be considered to have similar risks to the uncoated archwires. (Angle Orthod. 0000;00:000–000.