Correlation of alveolar bone thickness and central incisor inclination in skeletal Class I and II malocclusions with different vertical skeletal patterns: A CBCT study.

INTRODUCTION: This study aimed to assess the alveolar bone thickness (ABT) and labiolingual inclination of maxillary and mandibular central incisors in patients with Class I and II skeletal patterns with normal-angle, high-angle, and low-angle vertical patterns. METHODS: The study sample consisted of 200 cone-beam computed tomography scans of patients with skeletal Class I and II malocclusions. Each group was further divided into low-angle, normal-angle, and high-angle subgroups. Labiolingual inclinations of maxillary and mandibular central incisors and ABT were measured at 4 levels from the cementoenamel junction in the labial and lingual surfaces. The Kolmogorov-Smirnov test, independent t test, 2-way analysis of variance, and Spearman's correlation test were applied for statistical analyses. RESULTS: The only significant difference between Class I and II groups regarding the ABT was found at the labial side of the maxillary central incisor, 9 mm apical to the crest. At this level, the mean ABT was 0.87 mm in patients with a skeletal Class I malocclusion, which was significantly greater than that in patients with a skeletal Class II malocclusion with a mean ABT of 0.66 mm (P = 0.02). Comparisons among the vertical subgroups revealed that on the labial and lingual sides of the mandible, as well as the palatal side of the maxilla, significantly thinner alveolar bone was found in patients with high-angle growth patterns than those with normal-angle and low-angle patterns in both sagittal groups (P <0.05). Significant weak to moderate correlations were found between ABT and tooth inclination (P <0.05). CONCLUSIONS: Significant differences in ABT covering central incisors between patients with skeletal Class I and II malocclusion are merely observed at the labial surface of the maxilla, 9 mm apical to the cementoenamel junction. Compared with patients with normal-angle and low-angle, those with a high-angle growth pattern and Class I and II sagittal relationships have thinner alveolar bone support around maxillary and mandibular incisors.

The contribution of orexin receptors within the ventral tegmental area to modulation of antinociception induced by chemical stimulation of the lateral hypothalamus in the animal model of orofacial pain in the rats.

Involvement of the ventral tegmental area (VTA) and the lateral hypothalamus (LH) in the modulation of formalin-induced nociception is well documented. In this study, we investigated the role of orexin 1 (OX1) and orexin 2 (OX2) receptors within the VTA in modulation of the LH-induced antinociception during both phases of orofacial formalin test. Male adult Wistar rats weighing 230-250 g were unilaterally implanted with two stainless steel guide cannulae in the VTA and LH. In two separate supergroups, animals received SB334867 (OX1 receptor antagonist) or TCS OX2 29 (OX2 receptor antagonist), at the doses of 3, 10, and 30 nM/rat into the VTA before intra-LH microinjection of carbachol (250 nM/rat) as a nonselective cholinergic receptor agonist for chemical stimulation of orexinergic neurons in this region. Rats were subcutaneously injected with 1% formalin (50 µl; s) into the orofacial region, 5 min after intra-LH microinjection of carbachol or saline. The blockade of both orexin receptors in the VTA reduced intra-LH carbachol-induced antinociception. However, this effect was greater during the late phases of the orofacial formalin test. The blockade of the OX1 but not OX2 receptors in the VTA affect the pain-related behaviors during the early phase, and also, the contribution of OX2 receptor to modulate the LH-induced antinociceptive responses was greater than OX1 receptor during the late phase of orofacial formalin test. The results indicated the neural pathway projected from the LH to the VTA contributes to the modulation of formalin-induced orofacial pain. Orexinergic drugs might be considered as therapeutic agents for inflammatory pain treatment.

Effect of Bleaching Mouthwash on Force Decay of Orthodontic Elastomeric Chains.

INTRODUCTION: Force decay elastomeric chains are significant, and it is a clinical problem. AIM: The aim of this study was to evaluate the effects of bleaching agent in the mouthwash on the force decay of orthodontic chains. MATERIALS AND METHODS: In this experimental study, 160 gray closed elastomeric chains were randomly divided into three groups (one control and two test groups). Four loops of chains were stretched for 25 mm on custom-made jig. Control group specimens were immersed in artificial saliva during the test period. Test group specimens were immersed twice a day for 30 seconds in the whitening (LISTERINE® HEALTHY WHITE™) and daily sodium fluoride (LISTERINE® TOTAL CARE ZERO) mouthwashes. All specimens were immersed in artificial saliva at 37°C. Force was measured at different time points (initial, 1, 7, 14, 21, 28 days). Statistical analysis was performed by two-way analysis of variance (ANOVA) and Bonferroni methods (a = 0.05). RESULTS: Force of elastomeric chains was decreased dramatically in all groups during the experiment. After 24 hours, force was decreased by 42.18, 48.34, and 53.38% in control group, daily, and bleaching mouthwash groups respectively. The corresponding numbers after 4 weeks were 66.30, 76.73, and 86.48. The difference between three groups at days 1 and 28 was statistically significant (p < 0.05). CONCLUSION: Within the limitations of the current in vitro study, bleaching and sodium fluoride mouthwashes could cause force decay of orthodontic elastomeric chains. Whitening mouthwash is more weakening for elastomeric chains. CLINICAL SIGNIFICANCE: Use of whitening mouthwash by orthodontic patients could decrease the force of elastomeric chains, so it could be recommended to use them for a short time.

The short-term effects of face mask and fixed tongue appliance on maxillary deficiency in growing patients--a randomized clinical trial.

BACKGROUND: The purpose of this single blind, prospective, parallel randomized trial study was to compare the effects of face mask and fixed tongue appliance in treatment of Class III malocclusion with maxillary deficiency in growing patients. METHODS: 88 patients with maxillary deficiency were selected. 60 fulfilled the study requirements. The patients were randomly assigned to 2 groups by computer generated tables. One group was treated with removable face mask and the other group was treated by fixed tongue appliance. 4 of the patients dropped out of study leaving a final number of 56 patients. Thus, the face mask group included 30 patients (13 males, 17 females) with the mean age of 8.5 (SD 1.4) years and the fixed tongue appliance group included 26 patients (13 males, 13 females) with the mean age of 8.9 (SD 1.7) years. The patients Lateral cephalograms obtained at the beginning and end of the study were analyzed. RESULTS: Paired t-tests showed that SNA increased by 1.3° (SD 1.1°) in face mask group (P<0.001) and it increased by 1.8° (SD 0.9°) in fixed tongue appliance group (P<0.001). T-test showed that there were no statistically significant differences between the two groups except for SNB. IMPA decreased significantly in both groups. CONCLUSIONS: Both treatment modalities were successful in moving the maxilla forward and improving the profile of the patients; however, the bulky size of face masks might reduce patients' compliance and make them less favorite choice of treatment.

A comprehensive review of oral microenvironment changes and orofacial adverse reactions after COVID-19 vaccination: The good, the bad, and the ugly.

Background and Aims: Anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines have the potential to alter several biological systems concurrently with remolding the immune system, most of which are related to immunization, while some others are known as adverse effects. This review aims to explore the potential effects of vaccination on the oral microenvironment and classifies them as good, bad, or ugly, with a brief review of facial diseases following coronavirus disease 2019 (COVID-19) vaccination. Methods: This study was a comprehensive review conducted through searching related articles in Medline, Scopus, and Google Scholar databases. Results: On one side, the "Good" impacts of vaccination on the oro-nasal mucosa are explained as if the mucosal immune responses followed by SARS-CoV-2 vaccines are enough to provide immunity. On the other side, the possible "Bad" and "Ugly" effects of the vaccine, which manifest as orofacial adverse events and autoimmune reactivations, respectively, should be noted. Exacerbation of pre-existing autoimmune conditions such as lichen planus, pemphigus vulgaris, bullous pemphigoid, and Stevens-Johnson syndrome have been reported. Conclusion: COVID-19 vaccines could affect different biological systems alongside stimulating the immune system, and some of these effects are referred to as adverse effects. Nonetheless, these adverse effects are treatable, and healthcare professionals should not prevent patients from taking the first available vaccination.

Evaluation and comparison of antibacterial and physicochemical properties of synthesized zinc oxide-nano particle-containing adhesive with commercial adhesive: An experimental study.

INTRODUCTION: Enamel surface demineralization is one of the most common issues occurring subsequent to orthodontic treatments. This study aims to synthesize a homogenous adhesive, containing zinc oxide nano particles for the purpose of evaluation of antibacterial and mechanical properties in bonding of orthodontic brackets. MATERIALS AND METHODS: Assessments were based on three groups: a control group (synthesized adhesive), ZnO group (synthesized adhesive containing 1.3% mass fraction of zinc oxide nano particles), and XT™ group (Transbond™ XT™, 3M™, USA). Biofilm formation inhibition test was utilized for the evaluation of antibacterial effects and physicochemical tests were further utilized for the assessment of shear bond strength (SBS), adhesive remnant index (ARI), microhardness, degree of conversion (DC), water sorption and water solubility. RESULTS: In terms of antibacterial properties, ZnO-containing adhesives demonstrated a significant difference compared to the control group (P=0.001). The addition of ZnO to the synthesized adhesive did not result in any significant difference compared to the control and XT™ groups in terms of shear bond strength (P=0.007). CONCLUSIONS: Implementation of 1.3% mass fraction of zinc oxide nano particles in synthesized adhesive can add significant antibacterial characteristics and prevent biofilm formation without affecting the structural, mechanical, and chemical properties of the adhesive.

Estimating and comparing the duration of adolescent growth peak in skeletal class I and III subjects using cervical vertebral maturation method.

BACKGROUND: Estimating skeletal maturation and growth potential is essential for developing adolescents' best orthodontic treatment plan. The purpose of this study was to compare the duration of adolescent growth peak in subjects of skeletal classes I and III using the cervical vertebral maturation (CVM) method. METHODS: This retrospective cross-sectional study included 116 Iranian subjects (skeletal class I = 68, skeletal class III = 48) aged 8-16 years old and without previous orthodontic treatments. Using Steiner and Wits analyses, two independent examiners traced pre-treatment lateral cephalograms to determine the subjects' skeletal relationship. The skeletal maturation was then assessed using Baccetti's CVM method. The onset and duration of adolescent growth peak (interval of CS3-CS4) were compared between two skeletal classes and two genders using independent samples t test. RESULTS: In skeletal class I and III subjects, the adolescent peak had a mean duration of 1.62 (± 1.33) and 2.00 (± 1.27) years, respectively. The average difference of 0.38 years (4.6 months) between the two groups was statistically significant (p < 0.001). Furthermore, the onset age of adolescent growth peak was 11.91 (± 1.32) and 12.08 (± 1.31) years old in class I and III subjects, respectively. This age difference was not statistically significant (p = 0.630). Males' adolescent growth peak occurred 1.44 years later (p < 0.001) and lasted 0.20 years less (p < 0.001). CONCLUSIONS: The adolescent growth peak started at a similar age in class I and III subjects, but the latter experienced the peak for 4.6 months longer. Moreover, females had an earlier and more extended adolescent growth peak.

Hyrax application as a tooth-borne distractor for maxillary advancement.

Distraction osteogenesis (DO) has become a mainstream surgical technique for patients with jaw deformities. The aim of this study was to report the use of internal DO in the treatment of maxillary hypoplasia in a patient with cleft lip and palate. The case illustrates a 17-year-old boy with class III malocclusion, maxillary deficiency, and cleft lip and palate. Because the patient was experiencing severe hypernasality, it was decided to treat him by DO. The treatment process began by mounting a hyrax in the upper jaw for lateral expansion. A second hyrax was mounted in a way to create anteroposterior expansion. One day after the second hyrax application, the patient underwent a modified Le Fort I osteotomy. He was instructed to turn the screws twice per day for 12 days. The treatment was continued by means of a conventional face mask for 2 months. After 16 months of active treatment, favorable correction of the skeletal problem was observed. The S-N-A angle increased by 5 degrees, and patient's hypernasality was comprehensively improved.

Effect of orthodontic forces on root length of immature mandibular second premolars: a split-mouth randomized clinical trial.

OBJECTIVE: To assess the effect of orthodontic forces on changes in root length of immature mandibular second premolars. METHODS: Sixty-four mandibular second premolars (MSP) with immature apices (left and right sides) of 32 patients aged between 10 and 13 years were evaluated. Orthodontic treatment was started after obtaining periapical radiographs (T1) from the MSPs of each patient. Brackets were bonded, except the ones of MSPs (left or right by random as control MSP, and the other side as test MSP). After 9-12 months, a second periapical radiograph (T2) was obtained from the MSPs of each patient. Then, brackets were bonded to the control MSPs, which were not bonded before. After 18 ± 3 months, a third periapical radiograph (T3) was obtained. Changes in root length were evaluated by using a new formula. The test and control MSPs at T1, T2 and T3 were compared using repeated measures ANOVA and parametric tests. P-value smaller than 0.05 was statistically significant. RESULTS: There was no significant difference between the test and control groups in the mean root length of MSP at T1 (p= 0.48) and T3 (p= 0.078). The root length at T2 (p= 0.001) was significantly different between test and control MSPs, and the test group showed longer root length than the control group. CONCLUSIONS: Orthodontic force applied for leveling and alignment of immature MSPs may not have destructive effects on the roots, and may accelerates root formation in short-term. Normal root length was achieved at the end of root development.

The impact of platelet-rich fibrin (PRF) on delayed tooth replantation: A preliminary animal study.

The aim of this study was to evaluate the effect of platelet-rich fibrin (PRF) placed in delayed replantation of mature extracted teeth. Sixteen intentionally extracted teeth in two mature beagle dogs were selected. In one quadrant of each jaw, the extraction sockets were filled with PRF prior to replantation, and the other quadrant served as control without PRF. All extracted teeth underwent endodontic treatment and dried for 60 min. Thereafter, they were replanted with a flexible splint. After 8 weeks, the animals were euthanised, and the histological sections examined. Less inflammatory root resorption was noted in the PRF group compared to the control (P = 0.031). However, there was no significant difference between the two groups with regard to new bone formation, inflammatory status, connective tissue healing and replacement resorption (P > 0.05). Using PRF in the extracted socket before delayed replantation did not provide any significant benefit other than reduced inflammatory root resorption.

The correlation between external apical root resorption and electric pulp test responses: a prospective clinical trial.

OBJECTIVE: The current study investigated the correlation between pulpal sensitivity to the electric pulp tester (EPT) and external apical root resorption (EARR) in four types of maxillary anterior teeth of fixed orthodontic treatment patients. METHODS: In this prospective cohort study, 232 anterior teeth of 58 patients (mean age 18.96 ± 6.13 years) treated with fixed orthodontic treatment were examined. The EPT readings were recorded at twelve time points immediately before archwire insertion. Root resorption of four maxillary incisors were measured by means of parallel periapical radiographs at three time intervals (six months interval from the start) through design-to-purpose software to optimize data collection. A multiple linear regression model and Pearson correlation coefficient were used to assess the association of EPT values and observed EARR (p< 0.05). RESULTS: The highest level of EPT measurement was recorded at initial visit, and then there was a decreasing trend in EPT level during treatment for the next six and twelve months. There was another increasing trend after six months till the finishing time of the treatment. There was a significant correlation between changes in root length and time of recording the root length (p< 0.001). There was significant positive correlation between changes in EPT level and amount of observed root resorption (p< 0.001). CONCLUSION: The relative decrease in electric pulp test level could be a diagnostic sign of root resorption during orthodontic treatment. Further studies with longer follow up are needed to confirm the current results.

Strength of attachment between band and glass ionomer cement.

AIM: To determine the strength of attachment between plain stainless steel band material and glass ionomer cement. METHODS: Seventy-five extracted upper premolars, free of visible structural defects, were used. The teeth were divided randomly into three groups and embedded in acrylic resin blocks. A short length of plain, stainless steel band material with a welded stainless steel standard edgewise 0.022 inch bracket was adapted to the buccal surface of each tooth. The bracket-stainless steel pads were then cemented to the teeth with either Bandtite (Group 1), Granitec (Group 2) or Ariadent (Group 3) glass ionomer cement and stored in an incubator at 37 degrees C for 30 days. The shear bond strengths of the specimens were measured and compared. RESULTS: The mean shear bond strengths (SBS) were significantly different: Bandtite 0.7331 +/- 0.056 Mpa; Granitec 0.3869 +/- 0.047 Mpa; Ariadent 0.2931 +/- 0.033 Mpa (ANOVA, p < 0.001). Tukey HSD post-hoc tests also showed significant differences between Bandtite and Granitec, Bandtite and Ariadent, and Granitec and Ariadent (p < 0.001). All specimens failed at the band-cement interface. CONCLUSION: The highest and lowest SBS were related to Bandtite and Ariadent cements, respectively. All cements had bond strengths less than the range of bond strengths considered to be clinically acceptable for bonded orthodontic attachments. Mechanical factors are important for band retention.

Correlation assessment of cervical vertebrae maturation stage and mid-palatal suture maturation in an Iranian population.

AIM: The aim of the current study was to evaluate the correlation of skeletal age based on cervical vertebrae maturation (CVM) stage and mid-palatal suture (MPS) maturation in an Iranian population. MATERIAL AND METHODS: This was a cross-sectional analytic study. A total number of 93 samples were included. Samples were taken from patients who were in CS3 to CS6 stages of CVM who had cone-beam computed tomography and lateral cephalometry based on inclusion criteria. The maturation of MPS was assessed based on the cone-beam computed tomography images. In the classification of maturation of MPS, there are five stages (A-E) and the suture fusion occurs in stage D. In stage E, the suture is fused completely. The CVM stage (CS1-6) was also assessed based on the lateral cephalograms. Data were analyzed using Spearman correlation with a significance level of 0.05. RESULTS: A total of 51 female individuals with a mean age of 14.98 ± 4.806 and 42 male individuals with a mean age of 15.79 ± 5.135 participated in this study. The correlation coefficient between the CVM stage and MPS maturation was 0.691 in female and 0.754 in male individuals (P < 0.001). Stage D was correlated with CS4. CONCLUSION: The results demonstrated that CVM stages had a significant but moderate positive correlation with the maturation of MPS. Until CS3, the MPS has not been fused and in CS6 the MPS is fused definitely.

Effect of different debonding techniques on shear bond strength and enamel cracks in simulated clinical set-ups.

OBJECTIVE: The aim of this study was to evaluate the relationship between debonding forces and enamel cracks length change between different debonding techniques. METHODS: 80 extracted premolar teeth with intact buccal enamel were divided into five groups. In each group, enamel cracks were evaluated by stereomicroscope before and after debonding. All teeth were bonded with metal brackets by self-cure adhesive (3M, USA) and then debonded by bracket debonding plier, fixed on the UTM machine, through five methods based on location of plier on brackets: OGwing (occlusogingival), MDwing (mesiodistal), Oblique, OGbase (occlusogingival) and Cusp-base. RESULTS: Based on non-parametric distribution of data, there was no significant difference between groups in ARI and enamel cracks length change. The highest shear bond strength for debonding presented in OG base method (25.25 ± 8.4) and the difference was statistically significant (P-value = 0.029). There was no linear relationship between shear bond strength and cracks length change and also between ARI and cracks length change. CONCLUSION: Despite the lower cracks length change in Cusp-base method than other groups, there wasn't significant difference between debonding methods. Also the amount of debonding forces and ARI do not affect the changes of cracks length.

Relationship of the rs10850110 and rs11611277 polymorphisms of the MYO1H gene with non-syndromic mandibular prognathism in the Iranian population.

BACKGROUND: The myosin 1H (MYO1H) gene, located on chromosome 12, encodes the unconventional MYO1H protein, which is involved in the intracellular movement and morphology of chondrocytes, and plays a vital role in the prognathism or retrognathism of the mandible. OBJECTIVES: The objective of this study was to assess the relationship between the polymorphisms of the MYO1H gene and mandibular prognathism in the Iranian population. MATERIAL AND METHODS: The current project evaluated 64 patients with mandibular prognathism requiring orthognathic surgery and 60 controls with skeletal class I occlusion. Genome amplification was performed using specific primer pairs to assess the rs10850110 and rs11611277 polymorphisms of the MYO1H gene through the polymerase chain reaction (PCR). The restriction fragment length polymorphism (RFLP) technique was used to detect single-nucleotide polymorphisms. The data was analyzed using the χ2 test. RESULTS: The patient and control groups were not significantly different in terms of age or gender (p > 0.05). In all, 3.1% of patients and 6.7% of controls had the rs10850110 polymorphism (p = 0.680), and 1.6% of patients and 5% of controls had the rs11611277 polymorphism (p = 0.602). CONCLUSIONS: No significant correlation was noted between the rs10850110 and rs11611277 polymorphisms of the MYO1H gene and mandibular prognathism in the Iranian population. However, the lower frequency of these polymorphisms in the patient group suggests a possible association with mandibular retrognathism, which needs to be investigated with a larger sample size.

Treatment of an Adult Skeletal Class III Patient with Surgically Assisted Rapid Palatal Expansion and Facemask.

This case report presents the treatment of a 21-year-old male patient with class III skeletal malocclusion, an open bite, and vertical growth pattern. He was managed with surgically assisted rapid palatal expansion (SARPE) along with an orthopedic facemask. The duration of treatment was 16 months. Significant improvement and favourable outcome were observed concerning both facial appearance and paraclinical parameters after completion of treatment.

Common conditions associated with displacement of the inferior alveolar nerve canal: A radiographic diagnostic aid.

PURPOSE: This study reviewed the common conditions associated with displacement of inferior alveolar nerve canal. MATERIALS AND METHODS: General search engines and specialized databases including Google Scholar, Pub Med, Pub Med Central, Science Direct, and Scopus were used to find relevant studies by using keywords such as "mandibular canal", "alveolar canal", "inferior alveolar nerve canal", "inferior dental canal", "inferior mandibular canal" and "displacement". RESULTS: About 120 articles were found, of which approximately 70 were broadly relevant to the topic. We ultimately included 37 articles that were closely related to the topic of interest. When the data were compiled, the following 8 lesions were found to have a relationship with displacement of mandibular canal: radicular/residual cysts, dentigerous cyst, odontogenic keratocyst, aneurysmal bone cyst, ameloblastoma, central giant cell granuloma, fibrous dysplasis, and cementossifying fibroma. CONCLUSION: When clinicians encounter a lesion associated with displaced mandibular canal, they should first consider these entities in the differential diagnosis. This review would help dentists make more accurate diagnoses and develop better treatment plans according to patients' radiographs.

Common conditions associated with mandibular canal widening: A literature review.

PURPOSE: The aim of this study was to review the common conditions associated with mandibular canal widening. MATERIALS AND METHODS: General search engines and specialized databases including Google Scholar, PubMed, PubMed Central, Science Direct, and Scopus were used to find relevant studies by using the following keywords: "mandibular canal," "alveolar canal," "inferior alveolar nerve canal," "inferior dental canal," "inferior mandibular canal," "widening," "enlargement," "distension," "expansion," and "dilation." RESULTS: In total, 130 articles were found, of which 80 were broadly relevant to the topic. We ultimately included 38 articles that were closely related to the topic of interest. When the data were compiled, the following 7 lesions were found to have a relationship with mandibular canal widening: non-Hodgkin lymphoma, osteosarcoma, schwannoma, neurofibroma, vascular malformation/hemangioma, multiple endocrine neoplasia syndromes, and perineural spreading or invasion. CONCLUSION: When clinicians encounter a lesion associated with mandibular canal widening, they should immediately consider these entities in the differential diagnosis. Doing so will help dentists make more accurate diagnoses and develop better treatment plans based on patients' radiographs.

Agreement of the clinician's choice of archwire selection on conventional and virtual models.

OBJECTIVES: To compare archwire selection on dental casts with archwire selection using a three-dimensional (3D) software program (OrthoAid) and assess agreement between clinicians. MATERIALS AND METHODS: The best-fitting archwires were selected for dental casts of 100 patients with malocclusion using two approaches by three orthodontists. The first method was to visually determine the fitness of five preformed nickel titanium archwires to the arch form on a dental cast (subjective method). The second method was archwire selection on a virtual image of the same cast by means of 3D software (objective method). Agreement between selections performed by the orthodontists was calculated using Kappa statistics. The accuracy of fit of the archwires to the curves fitted to the arch form was also calculated or reversely assessed by means of the root mean square (RMS) for both methods using the Dahlberg formula. RESULTS: The mean RMS of the distances between the patient arch forms and the archwires for the subjective method was 1.163-1.366 mm. The agreement of selections between orthodontists was 42%-58% (Kappa ranged from .074 to .382). Using the 3D software (objective method), the mean RMS decreased to 0.966-1.171 mm, and agreement increased to 47% to 84% (Kappa ranged from .444 to .747). CONCLUSIONS: The use of 3D computer software for archwire selection in patients with malocclusion provided better adaptation and interexaminer reliability.

Impact of malocclusion severity on oral health-related quality of life in an Iranian young adult population.

OBJECTIVE: This study aimed to assess the relationship between malocclusion severity and oral health-related quality of life (QoL) of 18 to 25-year-old Iranians who sought orthodontic treatment. MATERIALS AND METHODS: A total of 126 patients between 18 and 25 years attending some private orthodontic clinics answered the oral health impact profile-14 (OHIP-14) and a demographic questionnaire. Two calibrated orthodontists recorded the Index of Orthodontic Treatment Need-Dental Health Component (IOTN-DHC) determining the severity of malocclusion (Kappa = 0.8). The IOTN-Aesthetic Component (IOTN-AC) was reported by patients for assessing the perception of their esthetic severity of malocclusion. Logistic regression analysis was used. Level of significance was set at α = 0.05. RESULTS: The mean score of OHIP-14 was 20.87 ± 8.6. The frequency of patients with no/slight, borderline, and definite need for orthodontic treatment was determined as 13.4%, 23.8%, and 62.7%, respectively, by IOTN-DHC. There were significant correlations between borderline or definite need treatment and OHIP-14 overall score (P < 0.05). Patients with borderline and definite need for orthodontic treatment had 5 and 21 times lower QoL, respectively, than those with a slight need for orthodontic treatment. Based on IOTN-AC, 50.8% of the patients mentioned slight or no need based on IOTN-AC. No significant association was noted between IOTN-AC and OHIP-14 overall scores. CONCLUSIONS: The results showed negative impact of malocclusion severity on the QoL. This study highlighted the importance of individual assessment of orthodontic patients.