Comparison of personality traits,attitude toward orthodontic treatment,and pain perception and experience before and after orthodontic treatment

Objective:To compare personality traits, attitude toward orthodontic treatment, and pain perception and experience before and after orthodontic treatment.Materials and Methods:One hundred subjects (50 male and 50 female) were included in this study. The mean (SD) age was 17.5 (2.05) years at T1 and 19.15 (2.32) years at T2. The instruments for data collection were questionnaires that included assessment of patients'' personality traits, attitudes toward orthodontic treatment, and pain perception/experience. Subjects completed the questionnaires at two different times: before orthodontic treatment (T1) and after fixed orthodontic treatment (T2). Subjects were treated by fixed orthodontic appliances for an average (SD) period of 18.64 (0.35) months. Paired sample t-test and chi-square test were used to detect any differences.Results:Significant changes in personality traits were detected after orthodontic treatment irrespective of gender. Neuroticism, openness, agreeableness, and conscientiousness scores were improved (P < .001). A positive attitude toward orthodontic treatment was reported at T1 (4.31 [±1.26]) and improved at T2 (3.98 [±1.16]) irrespective of gender (P < .05). The average (SD) expected pain score (T1) was 4.73 (1.88) and the average (SD) experienced pain score (T2) was 4.63 (1.58). Significant difference in the expected and experienced pain scores was not detected (P  =  .11).Conclusions:Personality traits and attitude toward orthodontic treatment improved after orthodontic treatment. Reported actual pain experience during orthodontic treatment was similar to that expected before treatment.     

Personality traits as a potential predictor of willingness to undergo various orthodontic treatments

Objective:To establish an association between patient personality traits and potential willingness to undergo various orthodontic treatments.Materials and Methods:One hundred adolescent individuals aged 12–16 years completed an anonymous electronic questionnaire via Survey Monkey. The 24-item questionnaire contained three major sections: patient demographics, a modified Big Five Inventory (BFI)-10 personality index, and a willingness to undergo treatment assessment. Multiple-variable linear regression analyses were used to determine the associations among age, gender, ethnicity, and the five personality traits simultaneously with willingness to undergo treatment. Statistical significance was set at P ≤ .05.Results:Ninety-six of the 100 individuals were included in the statistical analysis. Age, ethnicity, and gender failed to correlate with potential willingness to undergo orthodontic treatment. Several personality dimensions within the modified BFI-10 (agreeableness, conscientiousness, and neuroticism) were significantly associated with willingness to undergo various orthodontic treatments (P ≤ .05). Agreeableness demonstrated positive correlations with five treatment modalities, while both conscientiousness and neuroticism exhibited negative associations with a single treatment modality. Openness and extraversion were the only personality dimensions that failed to associate with any of the treatment modalities. Four of the nine treatment modalities had no association with patient demographics or a patient''s personality dimensions.Conclusions:Personality traits are useful in predicting a patient''s potential willingness to participate in various orthodontic treatments. The agreeableness dimension provided the most utility in predicting patient willingness. Age, ethnicity, and gender were not significant in predicting patient willingness.     

Desire for orthodontic treatment and associated factors among adolescents in southern Brazil

Objective:To estimate the prevalence of the desire for orthodontic treatment and investigate associated factors among adolescents in southern Brazil.Materials and Methods:A cross-sectional study was carried out with 704 adolescents aged 12 and 13 years at municipal public schools in the city of Balneário Camboriú (southern Brazil). The adolescents answered a previously tested questionnaire addressing satisfaction with their dental appearance, speech function, chewing function, and the desire for orthodontic treatment. The parents/guardians answered a questionnaire addressing satisfaction with their child''s dental appearance and socioeconomic variables. A trained and calibrated orthodontist collected clinical data on malocclusion using the Dental Aesthetic Index (DAI). Statistical analysis was performed using multivariate Poisson regression with robust variance.Results:The prevalence of the desire for orthodontic treatment was 69.6% (490/704). In the adjusted analysis, the outcome was significantly more prevalent among girls (P < .001), those with difficulty chewing (P  =  .026), those dissatisfied with their dental appearance (P < .001), and those with greater malocclusion severity (P < .001). The following orthodontic characteristics were associated with the desire for orthodontic treatment in the multivariate model: diastema in anterior segment (P < .001), anterior maxillary irregularity (P < .001), maxillary overjet ≥6 mm (P < .001), and mandibular overjet (P  =  .047).Conclusions:The desire for orthodontic treatment among 12- and 13-year-old adolescents is influenced by gender, dissatisfaction with one''s dental appearance, difficulty chewing, malocclusion severity, and orthodontic characteristics. These findings should be considered together with normative indications regarding the need for orthodontic treatment in adolescents.     

A pilot clinical study of Class III surgical patients facilitated by improved accelerated osteogenic orthodontic treatments

Objective:To evaluate if the improved accelerated osteogenic orthodontics (IAOO) procedure could speed Class III surgical patients'' preoperative orthodontic treatment duration and, if yes, to what extent. This study was also designed to determine whether or not an IAOO procedure affects the tooth-moving pattern during extraction space closure.Materials and Methods:The samples in this study consisted of 24 Class III surgical patients. Twelve skeletal Class III surgery patients served as an experimental group (group 1) and the others as a control group (group 2). Before treatment, the maxillary first premolars were removed. For group 1, after the maxillary dental arch was aligned and leveled (T2), IAOO procedures were performed in the maxillary alveolar bone. Except for this IAOO procedure in group 1, all 24 patients experienced similar combined orthodontic and orthognathic treatment. Study casts of the maxillary dentitions were made before orthodontic treatment (T1) and after extraction space closure (T3). All of the casts were laser scanned, and the amount of movement of the maxillary central incisor, canine, and first molar, as well as arch widths, were digitally measured and analyzed by using the three-dimensional model superimposition method.Results:The time durations T3–T2 were significantly reduced in group 1 by 8.65 ± 2.67 months and for T3–T1 were reduced by 6.39 ± 2.00 months (P < .001). Meanwhile, the tooth movement rates were all higher in group 1 (P < .05). There were no significant differences in the amount of teeth movement in the sagittal, vertical, and transverse dimensions between the two groups (P > .05).Conclusion:The IAOO can reduce the surgical orthodontic treatment time for the skeletal Class III surgical patient by more than half a year on average. The IAOO procedures do not save anchorage.     

Effects of surface treatment and artificial aging on the shear bond strength of orthodontic brackets bonded to four different provisional restorations

Objective:To evaluate the combined effects of material type, surface treatment, and thermocycling on the bond strength of orthodontic brackets to materials used for the fabrication of provisional crowns.Materials and Methods:Four materials were included in this study (ProTemp, Trim Plus, Trim II, and Superpont C+B). Sixty cylindrical specimens (1 × 3 cm) were prepared from each material and equally divided into three groups. The first group was ground with silica carbide paper, the second was polished with pumice, and the last group was sandblasted with 50-µm aluminum oxide particles. Stainless-steel maxillary central incisor brackets (Victory Series, 3M) were bonded to the provisional material specimens with Transbond XT light-cured composite resin, and half of the specimens from each group were thermocycled 500 times in 5°C and 55°C water baths. Then the brackets were debonded with shear testing, and the results were statistically analyzed by three-way analysis of variance and Tukey''s multiple-comparison tests at α  =  0.05. Adhesive Remnant Index (ARI) was also identified.Results:Before and after thermocycling, ProTemp materials showed the highest shear bond strength with orthodontic brackets (10.3 and 13.1 MPa, respectively). The statistical analysis indicated an interaction among the three independent variables (P < .05) and statistically significant differences in bond strength among provisional materials (P < .001), surface treatments (P < .001), and thermocycling (P < .05). According to the ARI, most groups demonstrated adhesive failure.Conclusions:The provisional material type, surface treatment, and artificial aging have a significant effect on bond strength. Sandblasting treatment exerts a beneficial effect on shear bond strength.     

Vibratory stimulation increases interleukin-1 beta secretion during orthodontic tooth movement

Objectives:To investigate the effects of application of vibratory stimuli on interleukin (IL)–1β secretion during maxillary canine distalization.Materials and Methods:Split-mouth design study in 15 subjects (mean age, 22.9 years; range 19–25 years) whose bilateral maxillary first premolars were extracted with subsequent canine distalization. On the experimental side, light force (60 g) was applied to the canine for 3 months in combination with vibratory stimuli provided using an electric toothbrush 15 minutes a day for 2 months; only orthodontic force was applied to the contralateral control canine. Gingival crevicular fluid (GCF) was collected from the mesial and distal sides of each canine at each monthly appointment. IL-1β levels were analyzed using an enzyme-linked immunosorbent assay. Canine movement was measured monthly.Results:Overall, enhanced IL-1β secretion was observed at the pressure sites of experimental canines compared to control canines (mean, 0.64 ± 0.33 pg/µL vs 0.10 ± 0.11 pg/µL, respectively, P < .001). The accumulative amount of tooth movement was greater for the experimental canine than for the control canine (mean, 2.85 ± 0.17 mm vs 1.77 ± 0.11 mm, respectively, P < .001).Conclusions:This study demonstrates that, in combination with light orthodontic force, application of vibratory stimuli using an electric toothbrush enhanced the secretion of IL-1β in GCF and accelerated orthodontic tooth movement.     

New diagnostic tenet of the esthetic midface for clinical assessment of anterior malar projection

Objective:To determine whether a visual classification of anterior malar support using vector relationships is supported by cephalometric analysis.Materials and Methods:Forty white subjects between the ages of 10 and 12 years, without craniofacial syndromes or previous orthodontic treatment, were equally divided into groups based on visual assessment of negative and positive vector relationships. Group A comprised 20 subjects (10 male, 10 female) exhibiting a positive vector relationship. Group B comprised 20 subjects (10 male, 10 female) displaying a negative vector relationship. Sella-nasion-orbitale (SNO) angulations were measured to evaluate the subjects'' anteroposterior position of the malar eminence relative to the cranial base. Gender differences and significant differences in SNO measurements between groups A and B were assessed with Mann-Whitney U-tests.Results:There was no statistically significant difference between genders. SNO angulations in the negative vector group were smaller than the positive vector controls by an average of 6.0 degrees, and the difference was highly significant (P < .0001).Conclusion:Compared with subjects exhibiting a positive vector relationship, individuals displaying a negative vector relationship had significantly reduced malar support. Anterior malar projection can be effectively classified through visual assessment of vector relationships.     

Class II subdivision treatment with the Forsus Fatigue Resistant Device vs intermaxillary elastics

Objective:To compare the effectiveness of comprehensive fixed appliance treatments implemented in combination with Forsus or intermaxillary elastics in Class II subdivision subjects.Materials and Methods:Twenty-eight Class II subdivision patients were allocated to two groups using matched randomization: Forsus group (mean age, 14.19 ± 1.02 years) and elastics group (mean age, 13.75 ± 1.16 years). Patients received fixed appliance therapy in combination with either Forsus or intermaxillary elastics. The study was conducted on lateral cephalograms and digital models acquired before orthodontic treatment and 10–12 weeks after the fixed appliances were removed.Results:The treatment phase comprising the use of Forsus (4.53 ± 0.91 months) was significantly shorter compared with elastics application (6.85 ± 1.08 months). This was also true for comparing duration of overall comprehensive treatment in both groups. Extrusion and palatal tipping of maxillary incisors and clockwise rotation of the occlusal plane were greater in the elastics group (P < .05). The mandibular incisors were proclined in both groups (P < .001), but no significant difference was observed between groups (P > .05). The mandibular incisors showed intrusion in the Forsus group and extrusion in the elastics group; the difference between groups was significant (P < .05). Overbite was decreased in both groups (P < .001) in similar amounts. Improvement in overjet, mandibular midline deviation, and correction of molar relationship on the Class II side were greater in the Forsus group (P < .05).Conclusion:Forsus is more effective for correcting Class II subdivision malocclusion in a shorter treatment period with minimal patient compliance required.     

Fixed Orthodontic Appliance Therapy and Its Impact on Oral Health-Related Quality of Life in Chinese Patients

Objective:To determine changes in oral health-related quality of life (OHRQoL) during fixed orthodontic appliance therapy in Chinese patients.Materials and Methods:Two-hundred fifty Chinese orthodontic patients completed six distinct intervals of the 14-item Oral Health Impact Profile (OHIP-14, Chinese version): before treatment (T0); after the placement of the fixed appliance at 1 week (T1), 1 month (T2), 3 months (T3), and 6 months (T4); and posttreatment (T5).Results:The overall response rate was 88.8% (222 of 250). Significant differences of overall OHIP-14 scores could be found between any two time points (P < .001), except for between T0 and T2 (P > .05) and between T3 and T4 (P > .05). Overall scores at T1 were significantly higher than the scores at the other intervals (P < .001), with a significant change in the scores on physical pain (P < .001), psychological discomfort (P < .001), and physical disability (P < .001). Scores at T5 were lowest among the six time points (P < .001).Conclusions:Fixed orthodontic appliance therapy did affect Chinese patients'' OHRQoL. Patients were considerably compromised in terms of their overall OHRQoL until approximately 1 month after insertion. The severity of the compromised condition in terms of overall OHRQoL was greatest at 1 week with the reported impact on physical pain, psychological discomfort, and physical disability. Patients'' OHRQoL was better after they completed the orthodontic treatment than before or during treatment.     

Impact of photobiomodulation and low-intensity pulsed ultrasound adjunctive interventions on orthodontic treatment duration during clear aligner therapy:: A retrospective study

ObjectiveTo assess the efficiency of low-intensity pulsed ultrasound (LIPUS) and photobiomodulation (PBM) interventions in accelerating orthodontic tooth movement during clear aligner therapy (CAT).Materials and MethodsThis retrospective study was carried out on the records of 84 subjects who were treated using CAT. Twenty-eight patients were treated using CAT with a daily use of LIPUS for 20 minutes, 28 patients were treated using CAT with a daily use of PBM for 10 minutes, and 28 patients were treated using CAT alone. The total duration of treatment was recorded for all patients. One-way analysis of variance and post hoc Tukey test were used to assess whether there was any significant difference in total treatment duration among the three groups (P < .05).ResultsThe mean treatment durations in days were 719 ± 220, 533 ± 242, and 528 ± 323 for the control, LIPUS, and PBM groups, respectively. The LIPUS group showed a 26% reduction, on average, in treatment duration when compared with the control group, whereas the PBM group showed an average 26.6% reduction in the treatment duration when compared with the control group. The results showed that there were statistically significant differences among the groups (P = .011). Treatment durations were significantly reduced in the LIPUS and PBM groups as compared with the control (P = .027 and P = .023, respectively), with no statistically significant differences between the LIPUS and PBM groups (P = .998).ConclusionsDaily use of LIPUS or PBM as adjunctive interventions during CAT could reduce the duration of orthodontic treatment.     

Effects of orthodontic treatment with aligners and fixed appliances on speech:: A randomized clinical trial

ObjectivesTo evaluate effects of orthodontic treatment with aligners and conventional fixed appliances on production of speech.Materials and MethodsThis was a parallel, randomized clinical trial. Patients with Angle Class I malocclusion, moderate crowding, and no speech impairment were randomly allocated to two groups: patients with orthodontic aligners (OAs; n = 20; mean age = 23.60 ± 5.65 years) and those with conventional fixed appliances (n = 20; mean age = 20.56 ± 4.51 years) and treated at the University of North Parana''s clinic in Londrina, Brazil. Evaluation of speech production was performed semiobjectively by a speech therapist (myofunctional orofacial examination) and subjectively (self-assessment) at five time points: baseline, immediately after insertion of appliances, and subsequently at 3, 30, and 180 days after insertion. For intergroup comparison, independent t, χ², Fisher exact, and Mann-Whitney tests were used; for intragroup comparison, the Friedman test was applied (α = 5%).ResultsIn the semiobjective evaluation, patients with OAs exhibited a change in production of speech production, compared with patients with fixed appliances, immediately and 3 days after insertion of appliances (P < .001). Thirty days after insertion, the groups were similar (P = .487), an outcome that was unchanged at 180 days. However, in the self-assessments, patients in both groups reported significant speech difficulties immediately and 3 days after insertion of appliances, but such impairment was no longer perceived at 30 days or 180 days.ConclusionsAlthough the speech therapist identified changes in speech production at the start of treatment in the OA group only, patient self-assessments demonstrated that orthodontic treatment, regardless of the type of appliance used, interfered with their perception of speech.     

Interventions for pain during fixed orthodontic appliance therapy: A systematic review

Objective:To compare the different methods of pain control intervention during fixed orthodontic appliance therapy.Materials and Methods:A computerized literature search was performed in MEDLINE (1966–2009), The Cochrane Library (Issue 4, 2009), EMBASE (1984–2009), and CNKI (1994–2009) to collect randomized controlled trials (RCTs) for pain reduction during orthodontic treatment. Data were independently extracted by two reviewers and a quality assessment was carried out. The Cochrane Collaboration''s RevMan5 software was used for data analysis. The Cochrane Oral Health Group''s statistical guidelines were followed.Results:Twenty-six RCTs were identified and six trials including 388 subjects were included. Meta-analysis showed that ibuprofen had a pain control effect at 6 hours and at 24 hours after archwire placement compared with the placebo group. The standard mean difference was −0.47 and −0.48, respectively. There was no difference in pain control between ibuprofen, acetaminophen, and aspirin. Other analgesics such as tenoxicam and valdecoxib had relatively lower visual analog scale (VAS) scores in pain perception. Low-level laser therapy (LLLT) was also an effective approach for pain relief with VAS scores of 3.30 in the LLLT group and 7.25 in the control group.Conclusions:Analgesics are still the main treatment modality to reduce orthodontic pain despite their side effects. Some long-acting nonsteroidal anti-inflammatory drugs (NSAIDs) and cyclo-oxygenase enzyme (COX-2) inhibitors are recommended for their comparatively lesser side effects. Their preemptive use is promising. Other approaches such as LLLT have aroused researchers'' attention.     

Long-term skeletal effects of high-pull headgear followed by fixed appliances for the treatment of Class II malocclusions

Objectives:The long-term skeletal effects of Class II treatment in growing individuals using high-pull facebow headgear and fixed edgewise appliances have not been reported. The purpose of this study was to evaluate the long-term skeletal effects of treatment using high-pull headgear followed by fixed orthodontic appliances compared to an untreated control group.Materials and Methods:Changes in anteroposterior and vertical cephalometric measurements of 42 Class II subjects (n = 21, mean age = 10.7 years) before treatment, after headgear correction to Class I molar relationship, after treatment with fixed appliances, and after long-term retention (mean 4.1 years), were compared to similar changes in a matched control group (n = 21, mean age = 10.9 years) by multivariable linear regression models.Results:Compared to control, the study group displayed significant long-term horizontal restriction of A-point (SNA = −1.925°, P < .0001; FH-NA = −3.042°, P < .0001; linear measurement A-point to Vertical Reference = −3.859 mm, P < .0001) and reduction of the ANB angle (−1.767°, P < .0001), with no effect on mandibular horizontal growth or maxillary and mandibular vertical skeletal changes. A-point horizontal restriction and forward mandibular horizontal growth accompanied the study group correction to Class I molar, and these changes were stable long term.Conclusions:One phase treatment for Class II malocclusion with high-pull headgear followed by fixed orthodontic appliances resulted in correction to Class I molar through restriction of horizontal maxillary growth with continued horizontal mandibular growth and vertical skeletal changes unaffected. The anteroposterior molar correction and skeletal effects of this treatment were stable long term.     

A retrospective study of Class II mixed-dentition treatment

Objective:To consider the effectiveness of early treatment using one mixed-dentition approach to the correction of moderate and severe Class II malocclusions.Materials and Methods:Three groups of Class II subjects were included in this retrospective study: an early treatment (EarlyTx) group that first presented at age 7 to 9.5 years (n = 54), a late treatment (LateTx) group whose first orthodontic visit occurred between ages 12 and 15 (n = 58), and an untreated Class II (UnTx) group to assess the pretreatment comparability of the two treated groups (n = 51). Thirteen conventional cephalometric measurements were reported for each group and Class II molar severity was measured on the study casts of the EarlyTx and LateTx groups.Results:Successful Class II correction was observed in approximately three quarters of both the EarlyTx group and the LateTx group at the end of treatment. EarlyTx patients had fewer permanent teeth extracted than did the LateTx patients (5.6% vs 37.9%, P < .001) and spent less time in full-bonded appliance therapy in the permanent dentition than did LateTx patients (1.7 ± 0.8 vs 2.6 ± 0.7years, P < .001). When supervision time is included, the EarlyTx group had longer total treatment time and averaged more visits than did the LateTx group (53.1 ± 18. 8 vs 33.7 ± 8.3, P < .0001). Fifty-five percent of the LateTx extraction cases involved removal of the maxillary first premolars only and were finished in a Class II molar relationship.Conclusion:EarlyTx comprehensive mixed-dentition treatment was an effective modality for early correction of Class II malocclusions.     

Differences in psychological traits between lingual and labial orthodontic patients: Perfectionism,body image,and the impact of dental esthetics

Objective:To examine some of the patients'' psychological traits in relation to their levels of perfectionism and their body image, and to discover whether these differ between lingual and labial orthodontic patients.Materials and Methods:A cross-sectional study was designed with a consecutive sample of 80 patients attending a private orthodontic office. Three questionnaires were used to assess the patients'' body image and level of perfectionism. The mean age was 33 years. The men numbered 32 and the women 48. The validated Spanish version of the Psychosocial Impact of Dental Aesthetic Questionnaire (PIDAQ) was used to assess the psychosocial impact of their dental esthetics. The Multidimensional Perfectionism Scale (MPS) was used to assess how perfectionist the patients were. A version of the Multidimensional Body-Self Relations Questionnaire (MBSRQ) was used for assessment of their body image. Student''s t-test was used to compare the means and 95% confidence intervals (P < .05), and a logistic regression model was used for multivariate analysis.Results:The PIDAQ (55.4 vs 60, P  =  .218) and MBSRQ (128.7 vs 125.9, P  =  .523) results of the patients who chose lingual orthodontics did not differ significantly from those who opted for labial orthodontics. However, the MPS scores of the lingual orthodontic patients were significantly higher (95.9 vs 86.3, P  =  .044), and high social class, over 30 years of age, and perfectionist traits were significant independent variables in this group.Conclusions:This pilot study may indicate that lingual orthodontic patients are more perfectionists than labial orthodontic patients.     

The impact of personality on adult patients' adjustability to orthodontic appliances

Objective:To evaluate the impact of psychological traits on patients'' choice of orthodontic appliances and their adjustability to orthodontic treatment.Materials and Methods:The sample consisted of 68 adult patients divided into three groups (28 buccal, 19 lingual, and 21 clear aligners). Prior to treatment participants filled out the Brief Symptom Inventory to assess symptoms of mental distress and the Narcissistic Vulnerability Scale to assess narcissistic personality traits. During the first week after appliance delivery and on day 14, patients completed a Health-Related Quality of Life questionnaire to assess their perception of pain and four areas of dysfunction. The correlation between personality traits and patients'' reaction to treatment was evaluated.Results:Somatization was the only trait that affected the choice of lingual and clear aligner appliance. Reduced self-esteem regulation was associated with increased pain in all patients, while exploitation was associated with pain in lingual patients. Narcissistic vulnerability slightly influenced patients'' adaptability to orthodontic appliances. Although adjustability to lingual appliances was the most difficult, only two parameters were affected by personality features. In the buccal group, adjustability was affected by numerous parameters. Adaptation to the clear aligner appliance was relatively uneventful and least affected by psychological features.Conclusion:Anxious individuals tend to prefer lingual and clear aligner appliances. The selection of lingual and clear aligner appliances governs the patient''s response and recovery process, leaving little room for the effect of psychological features. On the other hand, the buccal appliance allows for greater impact of personality traits on adjustability.     

Peridental bone changes after orthodontic tooth movement with fixed appliances: A cone-beam computed tomographic study

Objective:To quantify treatment-related changes in peridental bone height and thickness in orthodontic patients.Materials and Methods:Cone-beam computed tomographs (CBCTs) of 43 patients (24 female, 19 male; mean age: 25 years, 5 months) who underwent orthodontic treatment with multibracket appliances for at least 1 year were chosen for retrospective evaluation. Dehiscence depth and changes in bone width and tooth inclination were determined for 954 teeth.Results:There was a significant decrease in peridental bone height (dehiscence; −0.82 ± 1.47 mm) and bone thickness (−0.56 ± 0.7 and −0.69 ± 0.9 mm at 5 mm and 10 mm apical to the CEJ, respectively) during treatment (P < .001). A significantly greater dehiscence depth with increased vertical bone loss occurred in patients older than 30 years. In patients <30 years old, approximately 20% of the teeth showed defect depths >2 mm before treatment. In 90% of these patients, at least one tooth was affected. The maxillary canines and all mandibular teeth showed a higher risk for vestibular bone loss. Treatment changes in tooth inclination were correlated with horizontal bone loss.Conclusions:Based on these results, it seems reasonable to recommend that peridental bone in orthodontic patients older than 30 be evaluated on a routine basis due to the risk of increased vertical bone loss. Ninety percent of patients younger than 30 showed reduced bone height (dehiscence) of the periodontium of at least one tooth.     

Comparisons of soft tissue chin thickness in adult patients with various mandibular divergence patterns

Objective:To evaluate the association between soft tissue at the chin (STC) thickness and mandibular divergence.Materials and Methods:Nongrowing patients seeking orthodontic treatment (n  =  190; 113 women and 77 men), who had an average age of 26.94 years (range  =  18.10–53.50 years), were stratified in four subgroups based on cephalometric mandibular plane inclination to anterior cranial base (MP/SN): low  =  MP/SN ≤ 27° (n  =  48); medium-low  =  27° < MP/SN ≤ 32° (n  =  60); medium-high  =  32° < MP/SN < 37° (n  =  37); and high  =  MP/SN ≥ 37° (n  =  45). The STC thicknesses were measured at pogonion (Pog), gnathion (Gn), and menton (Me). Group differences were evaluated with two-way analysis of variance and Student''s t-test. The Pearson product moment correlation gauged associations between parameters.Results:The STC values were greater in men than women (P < .02) and were smaller in the high group (7.47 ± 2.42 mm) than in all other groups at Gn (mean values  =  9.00 mm < STC < 9.58 mm; P < .001) and at Me (high group  =  6.30 ± 1.89 mm; other groups  =  7.15 mm < STC< 7.57 mm; P  =  .011).Conclusion:The STC is thinner at Gn and Me in hyperdivergent facial patterns, apparently in contrast to Pog. This differential thickness warrants focused research as it implies that it is possible (1) to vertically grow hard tissues impinging on the inferior soft tissue envelope in patients with severe hyperdivergence and (2) to plan for genioplasty in such patients when more advancement of the chin might be needed to compensate for the increased vertical height.