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Analysis of pain level in cases treated with Invisalign aligner: Comparison with fixed edgewise appliance therapy

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Koji Fujiyama
Koji Fujiyama
Koji Fujiyama
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Tadashi Honjo at Tottori University
Tadashi Honjo
Makoto Suzuki
Makoto Suzuki
Makoto Suzuki
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Shinya Matsuoka
Shinya Matsuoka
Shinya Matsuoka
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The aim of this study was to evaluate and compare the difference in the level of pain using the visual analog scale (VAS) between cases treated with the edgewise appliance and Invisalign. In addition, the cause of pain and discomfort in the Invisalign cases was identified. The sample consisted of 145 cases for the edgewise group (EG; n = 55), Invisalign group (IG; n = 38), and edgewise and Invisalign group (EIG; n = 52). VAS scores were collected during the first three stages (first stage: 0 to 7 days, second stage: 14 to 21 days, and third stage: 28 to 35 days) and at the end of the treatment (overall VAS score). Evaluation of the cause of pain was categorized into three different types of problem (category 1: non-smoothed marginal ridge or missing materials, category 2: deformation of attachments, and Category 3: deformation of the tray). Statistical comparison of VAS scores between groups was performed by two-way analysis of variance. A significantly higher VAS score was observed at 3 and 4 days after, at 1, 2, and 3 days after, and at 2 and 3 days after in stages 1, 2, and 3, respectively, in EG compared to EIG and IG. A significant difference was observed in overall VAS scores between EG and IG in intensity of pain, number of days that pain lasted, and discomfort level. Only intensity of pain resulted in a significant difference between EG and EIG. Most of the causes of problem in the Invisalign cases were deformation of the tray. Invisalign may offer less pain compared to the edgewise appliance during the initial stages of treatment. In the use of Invisalign, deformation of tray must be carefully checked to avoid pain and discomfort for the patients.
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... The majority of studies were published in orthodontic-based journals (n = 20; 54.05%) [6,[29][30][31][32][33][34][35][36][37][38][39][40][41][42][43][44][45][46][47]. The AJODO was the journal which reported most studies (n = 5; 13.51%) [30,36,[38][39][40], followed by the EJO (n = 3; 8.11%) [33,34,42] and Progress in Orthodontics (n = 3; 8.11%) [43,46,47]. ...
... The majority of studies were published in orthodontic-based journals (n = 20; 54.05%) [6,[29][30][31][32][33][34][35][36][37][38][39][40][41][42][43][44][45][46][47]. The AJODO was the journal which reported most studies (n = 5; 13.51%) [30,36,[38][39][40], followed by the EJO (n = 3; 8.11%) [33,34,42] and Progress in Orthodontics (n = 3; 8.11%) [43,46,47]. Three studies were published in general dentistry journals [25,28,48], 13 studies in other scientific journals [23,24,26,27,[49][50][51][52][53][54][55][56][57], and one was a post-graduate thesis [58]. ...
... Pain was evaluated as part of a questionnaire in 20 studies [23, 24, 28, 29, 31, 33, 34, 39, 40, 42, 45-47, 49, 51-53, 55-57]. Other studies evaluated pain using the Visual Analogue Scale (VAS) alone [6,27,32,42,43], in combination with a daily diary [38,41], or as part of a semi-structured interview [30,58]. The VAS involves patients marking their pain level along a linear scale, enabling visual reflection of the patient's pain experience. ...
Patient experiences with clear aligners: a scoping review
Article
Full-text available
  • Apr 2025
  • EUR J ORTHODONT
Introduction Clear aligner therapy (CAT) is an aesthetic alternative to fixed appliance therapy (FAT). An understanding of patient experiences with CAT can enable clinicians to educate patients, manage expectations, and identify potential barriers to effective treatment. A scoping review was undertaken to map and synthesise the available evidence on patient experiences with CAT. Methods The review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR) guidelines. The PubMed (MEDLINE), Embase, Scopus, Web of Science and Dentistry & Oral Sciences Source databases and grey literature were searched. Data collation and synthesis was presented in descriptive and tabular formats. Results The initial search yielded 541 articles following removal of duplicate studies. 37 studies met the selection criteria and were scoped in the present review. The studies identified included cross-sectional, longitudinal, prospective, and randomised clinical trials reporting on patient experiences with CAT associated with Oral Health-Related Quality of Life (OHRQOL) and satisfaction. The impacts of CAT on OHRQOL with relevance to pain was the most frequently evaluated aspect, followed by speech, satisfaction, eating, anxiety, and sleep. Conclusions CAT patients report satisfaction with the aesthetics of the appliance however can expect transient negative effects on OHRQOL, pain, anxiety, and speech after commencing treatment. Further longitudinal research using validated qualitative tools focussing on CAT is required. Registration This review was registered in the Open Science Framework database (DOI: xx)
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... [4][5][6][7] Moreover, patients may experience discomfort during eating and daily activities. 8,9 Clear aligners offer distinct advantages over fixed appliances, including superior aesthetics, enhanced comfort, and improved oral hygiene. 3,8 The accuracy and efficiency of aligner therapy remain controversial. ...
... 8,9 Clear aligners offer distinct advantages over fixed appliances, including superior aesthetics, enhanced comfort, and improved oral hygiene. 3,8 The accuracy and efficiency of aligner therapy remain controversial. 10,11 Generally, the more complex the treatment case, the less satisfactory the outcome. ...
... Finally, treatment using clear aligners was considered. 3,8 However, it was anticipated that aligner therapy would pose difficulties in adjusting the right mandibular canine. 7,8 To address this, it was planned to manage the problem by using a bracketless NiTi wire first, followed by clear aligners to detail the remaining malocclusion. ...
Micro-implant Uprighting cantilever for the correction of a severely rotated and angulated mandibular canine during clear aligner treatment
Article
  • Mar 2025
Root movements and the rotation of a round-shaped tooth are known to be particularly challenging using clear aligners. This case report describes effective and efficient hybrid mechanics, combining aligners and a micro-implant uprighting cantilever, to correct a rotated and angulated mandibular canine. A 28-year-old male patient sought treatment for moderate crowding and presented with a severely rotated and angulated right mandibular canine, which required significant root movement to correct. Despite 12.5 months of treatment using a bracketless wire in resin slots plus clear aligners, the canine rotation and angulation remained uncorrected. Consequently, a nickel-titanium cantilever supported by a micro-implant was added to the aligner treatment. The desired mesial-out crown rotation and distal root movement of the canine occurred in 5.5 months. Adding an auxiliary cantilever when treating severely rotated and angulated teeth in clear aligner treatment is worthy of consideration.
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... [4][5][6][7] Moreover, patients may experience discomfort during eating and daily activities. 8,9 Clear aligners offer distinct advantages over fixed appliances, including superior aesthetics, enhanced comfort, and improved oral hygiene. 3,8 The accuracy and efficiency of aligner therapy remain controversial. ...
... 8,9 Clear aligners offer distinct advantages over fixed appliances, including superior aesthetics, enhanced comfort, and improved oral hygiene. 3,8 The accuracy and efficiency of aligner therapy remain controversial. 10,11 Generally, the more complex the treatment case, the less satisfactory the outcome. ...
... Finally, treatment using clear aligners was considered. 3,8 However, it was anticipated that aligner therapy would pose difficulties in adjusting the right mandibular canine. 7,8 To address this, it was planned to manage the problem by using a bracketless NiTi wire first, followed by clear aligners to detail the remaining malocclusion. ...
Micro-implant Uprighting cantilever for the correction of a severely rotated and angulated mandibular canine during clear aligner treatment
Article
Full-text available
  • Mar 2025
Root movements and the rotation of a round-shaped tooth are known to be particularly challenging using clear aligners. This case report describes effective and efficient hybrid mechanics, combining aligners and a micro-implant uprighting cantilever, to correct a rotated and angulated mandibular canine. A 28-year-old male patient sought treatment for moderate crowding and presented with a severely rotated and angulated right mandibular canine, which required significant root movement to correct. Despite 12.5 months of treatment using a bracketless wire in resin slots plus clear aligners, the canine rotation and angulation remained uncorrected. Consequently, a nickel–titanium cantilever supported by a micro-implant was added to the aligner treatment. The desired mesial-out crown rotation and distal root movement of the canine occurred in 5.5 months. Adding an auxiliary cantilever when treating severely rotated and angulated teeth in clear aligner treatment is worthy of consideration.
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... This apical root resorption (ARR) prevalence appears to be similar to or lower than that observed with fixed appliances. 12,13 According to Baumrind's research data, the prevalence of ARR ranges from 20% to 100% among orthodontic patients. 14 Severe ARR, characterized by resorption exceeding 5 mm or one-fourth of the root length, is rare, with an incidence between 1% and 5%. ...
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... The advantages of self-ligating brackets include shorter treatment times, less subjective discomfort and better periodontal health [10,[12][13][14][15]. Different studies have compared pain levels in patients treated with brackets versus transparent aligners. Treatment with aligners has been reported to produce less pain in the first few days, but no statistically significant differences in pain levels have been observed in the phases after the start of treatment [9,[12][13][14][15][16]. Therefore, according to published studies, orthodontic treatment with transparent aligners does not represent a benefit concerning pain levels compared with fixed orthodontic appliances. ...
Influence of orthodontic archwire (nickel-titanium versus copper-nickel-titanium) on pain in adult patients in the aligning phase of treatment with self-ligating brackets (two months of follow-up): a prospective observational pilot study
Article
Full-text available
  • Feb 2025
Background: The aim of this pilot study was to analyze the influence of a nickel-titanium archwire (NiTi) and a copper-nickel-titanium archwire (Cu-NiTi) on pain levels in adult patients during the first two months of orthodontic treatment with self-ligating brackets. Methods: This prospective observational pilot study was carried out at the Dental Clinic of the University of Salamanca between 2023 and 2024. This study analyzed 30 adult orthodontic patients who began treatment with self-ligating brackets. The participants were distributed into two study groups (n = 15) for treatment with initial NiTi and Cu-NiTi archwires. At the beginning, a 0.014-inch archwire was used, and a 0.016-inch archwire was used after a month. The level of pain was measured using a visual analog scale (VAS) at the beginning of treatment (T0), at one month (T1), and at two months (T2). At each time point (T0, T1, and T2), pain was measured at baseline and at 4, 24, and 48 h after archwire placement or replacement. The data were analyzed using Spearman's correlation coefficient and the Mann-Whitney test (p < 0.05). Results: The mean age of the participants (n = 30) was 31.34 (± 6.05) years. The maximum pain peak was in the first 48 h after placing the initial archwire (5.57 ± 1.72). The age and sex of the participants did not influence the pain levels in the sample studied. The composition of the orthodontic archwire only influenced the pain levels at the beginning of treatment (T0) (p < 0.05); in this case, the NiTi group (1.73 ± 1.53) described a higher level of pain than that of the Cu-NiTi group (1.07 ± 1.36); in the rest of the follow-up period, no significant differences were observed. Conclusions: Within the limitations of this study, we observed that the orthodontic archwire material (nickel-titanium versus copper-nickel-titanium) only influenced pain levels at the beginning of orthodontic treatment.
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Current Dental Studies IV (Bahar)
Book
  • Apr 2025
Current Approaches in Clear Aligners Serkan ÖZTÜRK Göksu TRAKYALI Sanaz SADRY The Role of Systemic Antibiotics in Periodontal Diseases Gözde ERİMLİ Duygu KILIÇ The Role of Colostrum in Pediatric Dentistry Büşra MUSLU DİNÇ Enes Mustafa AŞAR Zeynep Şeyda YAVŞAN Contemporary Restorative Materials Kübra BİLGE Monochromatic Composite Resins Özge DUMAN ÖZBİLGİ
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Pain perception among patients with fixed appliances over invisalign aligners
Article
  • Mar 2025
  • Bioinformation
The pain perception among patients treated with fixed appliances over Invisalign aligners is of interest. Hence, a total of 75 participants were divided equally into 3 groups namely Group I - Invisalign, Group II - self ligating fixed appliances and Group III - conventional fixed appliance treatment. Perception of pain among patients was evaluated using a Visual Analog Scale (VAS) at 6 hours, 24 hours, 48 hours, and 1 week. Patients treated with Invisalign aligners showed lower pain compared to fixed appliances.
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Clear aligners: A network and bibliometric analysis of 50 pivotal articles
Article
Full-text available
  • Feb 2025
Background: A bibliometric analysis uses statistical and mathematical methods to analyze the published literature, extracting meaningful information that helps to identify trends, assess research impact, and visualize key data patterns through graphs and trendlines. Objectives: The aim of the study was to list the top 50 papers on clear aligners, evaluate them critically and apply a bibliometric analysis to investigate the achievements and prospects in this field of study. Material and methods: A computerized database search (Scopus) was conducted on September 24, 2023, to find articles on clear aligners published in the scientific literature between 2013 and 2023. The top 50 cited manuscripts were chosen. Author-based characteristics were obtained from the Scopus database. The dataset from Clarivate™ InCites Benchmarking & Analytics™ and Journal Citation Reports (JCR) was used to determine parameters based on journals and articles. To improve the visual analysis, the keywords were collected systematically from the chosen articles. Results: The database search produced a directory of the 50 most often cited articles out of 1,405 papers. Of the 50 most frequently cited works on clear aligners, 35 (70.0%) were original research studies and 15 (30.0%) were reviews. The keyword-network analysis indicated 'removable orthodontic appliance' as the most important and repetitive keyword. Conclusions: The results of the present bibliometric study indicated that clear aligner therapy (CAT)-related papers received increasing citations. The study determined the most influential articles by highlighting their authors and the journals in which the papers were published.
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A comparative study of two different clear aligner systems
Article
Full-text available
  • May 2014
Background This study aims to compare the ‘Nuvola®’ system with ‘Fantasmino®’ system, examine their material properties, and define the indications for use of the aligners. Methods Two groups of patients were selected and were respectively treated with Nuvola® aligner and Fantasmino® system. Results The goal of treatment has been achieved with the two systems. Conclusions The two types of aligners have shown differences during the treatment. Fantasmino® system has elastic properties of high performance, but its size does not encourage compliance throughout the day. Nuvola® system determines good tooth movement and its size facilitates the patient’s collaboration. In both aligner systems, difficulties were found in the correction of torque information and rotations.
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Pain Experience during Initial Alignment with a Self-Ligating and a Conventional Fixed Orthodontic Appliance System
Article
Full-text available
  • Feb 2009
To test the hypotheses that (1) there is no difference in the pain experience during the week following initial placement of two orthodontic appliances (SmartClip and Victory; 3M Unitek, Monrovia, Calif); and (2) there is no difference in the pain experience during removal and insertion of orthodontic archwires with these brackets. Sixty-six consecutive patients were treated with a self-ligating bracket system (SmartClip) or a conventional appliance (Victory) on the basis of computer-generated random allocation. After appliance placement and engagement of a 0.016'' nickel-titanium archwire, pain experience was recorded after 4, 24, and 72 hours and after 7 days with the use of a visual analog system (VAS) questionnaire. At a subsequent visit, participants documented pain experiences during removal and insertion of 0.019 x 0.025'' archwires on an additional 100 mm VAS questionnaire. Independent t-tests and analyses of covariance were used to analyze normally distributed data; the Mann-Whitney U-test was used for skewed distributions. Forty-eight (72.2%) and fifty-one (77.3%) subjects completed the first and second parts of the study, respectively. Bracket type had no influence on pain experience at 4 hours (P = .958), 24 hours (P = .289), 72 hours (P = .569), and 7 days (P = .756) following appliance placement. However, bracket type significantly influenced pain experience during archwire removal (P = .001) and insertion (P = .013). Hypothesis 1 cannot be rejected. The bracket type had no effect on subjective pain experience during the first week after initial placement of two preadjusted orthodontic appliances. Hypothesis 2 was rejected. Significantly greater discomfort was experienced during archwire insertion and removal with the SmartClip appliance.
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A comparison of pain experienced by patients treated with labial and lingual orthodontic appliances
Article
  • Jun 2008
  • Ann Roy Australas Coll Dent Surg
There has been a paradigm shift within orthodontics in the use of lingual fixed appliances compared with the use of labial fixed appliances on the basis of perceived benefits and acceptance by patients. A matched case-control prospective longitudinal study of adult patients treated in the Orthodontic Department, Prince Philip Dental Hospital, Hong Kong. Group A consisted of 30 patients treated with lingual orthodontic appliances. Group B consisted of 30 patients treated with labial orthodontic appliances. Data were collected at five different time points using questionnaire: pre-treatment; one week after the placement of the fixed appliance, and then at 1-month, 3-months, and 6-months thereafter. The questionnaire consisted of 15 items, in which 11 items were rated on a visual analogue scale. Patients' experience of pain decreased over the study period (p < 0.001); Those treated with lingual appliances reported significantly greater pain experience than those treated with labial appliances with respect to tongue pain (p < 0.001). However, those treated with labial appliances reported experiencing significantly more lip pain (p < 0.01), cheek pain (p < 0.001), and gum pain (p < 0.05). Patients treated with lingual appliances reported experiencing pain earlier on than those treated with labial appliances (p < 0.05). Both groups reported the pain level to be the same throughout the day (p > 0.05). There was no significant difference in reported disturbance of sleep or analgesic consumption between the two groups (p > 0.05). Patients treated with both labial and lingual orthodontic appliances experienced pain during treatment, but this decreased over the treatment period. Patients treated with lingual appliances experienced more tongue pain whereas those treated with labial appliances experienced more lip, cheek and gum pain. Patients treated with lingual appliance reported experiencing pain earlier on than those treated with labial appliances.
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Adult patients' adjustability to orthodontic appliances. Part I: a comparison between Labial, Lingual, and Invisalign (TM)
Article
  • Jul 2011
  • EUR J ORTHODONT
This prospective study examined the adult patient's perception of recovery after insertion of three types of orthodontic appliances: Buccal, Lingual and Invisalign. The sample consisted of sixty-eight adult patients (45 females and 23 males) who comprised three groups: 28 Buccal, 19 Lingual, and 21 Invisalign patients. After appliance insertion, patients completed a Health-Related Quality of Life questionnaire daily for the first week and again on day 14, in order to assess patients’ perception of pain and analgesic consumption. In addition, four areas of dysfunction were assessed: oral dysfunction, eating disturbances, general activity parameters, and oral symptoms. Lingual appliance was associated with more severe pain and analgesic consumption, the greatest oral and general dysfunction, and the most difficult and longest recovery. The Invisalign patients complained of relatively high levels of pain in the first days after insertion; however this group was characterized by the lowest level of oral symptoms and by a similar level of general activity disturbances and oral dysfunction compared to the Buccal appliance. Many Lingual and some Buccal patients did not reach a full recovery from their eating difficulties by the end of the study period. The present study provides information to adult patients and clinicians assisting them in choosing the most appropriate treatment modality in relation to Health-Related Quality of Life parameters.
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A comparison of pain experienced by patients treated with labial and lingual orthodontic appliances
Article
  • Dec 2009
  • EUR J ORTHODONT
The aim of this prospective longitudinal study was to compare pain experiences among Chinese adult patients treated with labial and lingual orthodontic appliances. Sixty patients, 30 with labial appliances (18 females and 12 males, mean age 20.33 years, SD ± 4.205) and 30 with lingual appliances (22 females and 8 males, mean age 21.63 years, SD ± 2.236), rated their overall pain experience on a 100 mm visual analogue scale (VAS) at three time points: 1 week (T1), 1 month (T2), and 3 months (T3) after bracket placement. In addition, on a separate 100 mm VAS, they rated their pain experience at the locations of the tongue, lips, cheeks, gums, face, and jaw at T1, T2, and T3. Changes in pain VAS were conducted using Friedman analysis of variance, area under the curve (AUC) analysis and the data were compared using a t-test. There was no significant difference in global ratings of pain among those treated with labial or lingual appliances (P > 0.05). Among both groups, global ratings of pain decreased over the study period (P < 0.001). Patients treated with lingual appliances reported higher ratings of tongue pain (P < 0.001), while those treated with labial appliances reported higher ratings of lip (P < 0.001) and cheek (P < 0.001) pain. The findings indicate that patients treated with labial and lingual appliances rate similarly the level of overall pain they experience during treatment. Ratings of overall pain experienced decreased for both treatment groups with time. However, ratings of pain differed at various sites with respect to the type of orthodontic appliance. These findings have implications in informing patients’ treatment decision-making processes regarding labial and lingual appliances and in the management of discomfort associated with different treatment modalities.
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How well does Invisalign work? A prospective clinical study evaluating the efficacy of tooth movement with Invisalign
Article
  • Feb 2009
The purpose of this prospective clinical study was to evaluate the efficacy of tooth movement with removable polyurethane aligners (Invisalign, Align Technology, Santa Clara, Calif). The study sample included 37 patients treated with Anterior Invisalign. Four hundred one anterior teeth (198 maxillary and 203 mandibular) were measured on the virtual Treat models. The virtual model of the predicted tooth position was superimposed over the virtual model of the achieved tooth position, created from the posttreatment impression, and the 2 models were superimposed over their stationary posterior teeth by using ToothMeasure, Invisalign's proprietary superimposition software. The amount of tooth movement predicted was compared with the amount achieved after treatment. The types of movements studied were expansion, constriction, intrusion, extrusion, mesiodistal tip, labiolingual tip, and rotation. The mean accuracy of tooth movement with Invisalign was 41%. The most accurate movement was lingual constriction (47.1%), and the least accurate movement was extrusion (29.6%)- specifically, extrusion of the maxillary (18.3%) and mandibular (24.5%) central incisors, followed by mesiodistal tipping of the mandibular canines (26.9%). The accuracy of canine rotation was significantly lower than that of all other teeth, with the exception of the maxillary lateral incisors. At rotational movements greater than 15 degrees, the accuracy of rotation for the maxillary canines fell significantly. Lingual crown tip was significantly more accurate than labial crown tip, particularly for the maxillary incisors. There was no statistical difference in accuracy between maxillary and mandibular teeth of the same tooth type for any movements studied. We still have much to learn regarding the biomechanics and efficacy of the Invisalign system. A better understanding of Invisalign's ability to move teeth might help the clinician select suitable patients for treatment, guide the proper sequencing of movement, and reduce the need for case refinement.
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Esthetic Orthodontic Treatment Using the Invisalign Appliance for Moderate to Complex Malocclusions
Article
  • Sep 2008
In this report, three patients were treated with a new treatment protocol for Invisalign to demonstrate that a variety of complex malocclusions can be successfully treated using this protocol, including correction of moderate crowding, correction of moderate Class II division 1, and deep overbite. Previous studies of Invisalign showed significant limitations for more complex orthodontic treatment, although a few recent case reports have shown successfully completed moderate to difficult orthodontic malocclusions. One reason for the discrepancy is that the earlier studies were done during the first four years of the appliance development (now ten years of clinical use), when significant problems existed with accomplishing bodily movement, torquing of roots, extrusions, and rotations of premolars and canines. The new protocol included new methods for anterior/posterior corrections, showing on the computer the effect of elastics for Class II treatment simulated as a one-stage anterior/posterior movement at the end of treatment. Staging for interproximal reduction (IPR) is now automatically staged when there is better access to interproximal contacts to avoid IPR where significant overlap between teeth is present to avoid performing IPR on surfaces that may be damaged by instruments such as burs, strips, and disks when cut on a sharp angle. Staging for tooth movements is now also done to enable combination movements to occur simultaneously for each tooth with the tooth that needs to move the most (the lead tooth) determining the minimum number of stages required. All other teeth move at a slower rate than the lead tooth throughout the duration of treatment. Attachments are now placed in the middle of the crown automatically for rotation and automatically sized in proportion to the clinical crown. Use of 1 mm thick (buccal-lingual dimension) horizontal beveled rectangular attachments is standard on premolars for retention of aligners during intrusive movements, such as leveling the lower curve of Spee in deep overbite for extrusions and for control of the tooth long axis during torquing movements. Staging of tooth movements now track linear and rotational velocities of teeth separately with the number of treatment stages determined by the lead tooth based on its rotational or linear maximum velocities at no more than two degrees of rotation per stage. Simultaneous movements are done for all teeth providing visible space (approximately 0.05 mm) between teeth during movements past other teeth using expansion instead of IPR as a primary way to increase space available for correction of crowding.
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The pain and discomfort experienced during orthodntic treatment: A randomized controlled clinical trial of two intial aligning arch wires
Article
  • Nov 1992
  • AM J ORTHOD DENTOFAC
A randomized controlled clinical trial was performed to compare the nature, prevalence, intensity, and duration of pain related to the use of a relatively recently developed superelastic arch wire and a more traditional multistranded steel arch wire. Other factors likely to influence the pain experience were also investigated. Forty-three subjects participated in the study, the pain response being assessed by each of the visual analogue scales, the questionnaires, and an analgesic consumption record. In 18 of the 43 subjects a standardized preliminary dental extraction procedure was used as a control. Subsequent to the random allocation of an initial arch wire in 43 patients, 22 of them underwent a second arch wire in the opposing arch, the wire again being determined by random allocation. It was found that the prevalence, intensity, and duration of pain after the insertion of the two types of wire was similar but much greater than in the postextraction control phase. The pain score peaked on the morning after the placement of the arch wire, lasting typically for 5 to 6 days. The pain and discomfort experienced after the insertion of the second arch wire was similar to that of the first, no conditioning response being evident. Overall a diurnal variation was found with a tendency to an increase in pain in the evenings and nights, although this did not greatly affect sleep. The pain response was found to be highly and consistently subjective, not related to the dental arch, crowding, sex, or social class; however, a statistically significant association was found between the age and the pain experienced.
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The pain experience and psychological adjustment to orthodontic treatment of preadolescents, adolescents, and adults
Article
  • Nov 1991
  • AM J ORTHOD DENTOFAC
Age-related changes in psychological measurements of pain and well-being were studied in patients undergoing full fixed appliance orthodontic treatment. A longitudinal series of four questionnaires was used to obtain measurements of these factors after the separation phase of treatment, banding (2 to 7 days after separation), the first adjustment visit (3 to 4 weeks after placement of full fixed appliances), and the second adjustment visit (3-4 months after banding was completed). The results suggest an interaction between the phases of treatment and reported pain and psychological well-being and significant differences in the response profiles of the adolescent age group (14 to 17 years) compared to the preadolescent (11 to 13 years) and adult groups (18 years and older). These findings did not appear to be due simply to group differences in the use of analgesics, class of malocclusion, or type of full fixed appliance used. The profile comparisons indicated that the adolescent age group generally reported lower levels of psychological well-being and higher levels of pain during the phases of treatment examined. Consistent with these results was the finding that the adolescents differed from the preadolescents and adults in the quality of the pain experience reported during treatment. The results indicate an age difference in adjustment to fixed orthodontic therapy, which suggests that adolescents are more vulnerable to undesirable psychological effects of treatment.
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Perception of discomfort by patients undergoing orthodontic treatment
Article
  • Aug 1989
  • AM J ORTHOD DENTOFAC
The purpose of this study was to determine the perception of discomfort over time by a group of 70 patients undergoing orthodontic treatment. Patients who were selected for comprehensive orthodontic treatment completed questionnaires before insertion of separators and initial arch wires and after placement at 4 hours, 24 hours, and 7 days. The level of discomfort during these time periods was assessed by a visual analogue scale. The results showed a significant increase in the level of discomfort after insertion of either separators or arch wires at 4 hours and 24 hours, but not at 7 days. No significant difference was found in the level of discomfort of patients more than 16 years of age compared with those 16 years and under. No significant difference in discomfort was found between the sexes. These results are useful in relating expectations of discomfort to patients who undergo orthodontic treatment.
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