Double vs single primary tooth extraction in interceptive treatment of palatally displaced canines.

OBJECTIVES: To compare the impact of primary canine and primary first molar extractions with extractions of only the primary canine regarding correction of palatally displaced canines (PDCs). MATERIALS AND METHODS: Thirty-two children aged 9.5-13.5 years with 48 PDCs were randomly allocated to either the double-extraction group (DEG) or single-extraction group (SEG). Clinical and radiographic examinations were performed at baseline and at 6-month intervals until the canine emerged or orthodontic treatment was started. Outcome measures were: emergence of maxillary canine (yes/no), emergence of maxillary canine into a favorable position (yes/no), and maxillary canine positional change (angulation and sector). Factors influencing PDC emergence were analyzed using logistic regression. RESULTS: In the DEG, 64% (16/25) of canines emerged into the oral cavity vs 78% (18/23) in the SEG (P = .283). Favorable PDC position at trial end was seen in 64% (16/25) of the DEG vs 57% (13/23) of the SEG (P = .600). Significant distal movement of PDCs was recorded in the DEG and SEG, though no significant difference was observed between groups. Significant predictors of canine emergence were initial canine angulation (Angle A) (P = .008) and space conditions at T0 (P = .030). CONCLUSIONS: Double or single primary tooth extraction procedures are equivalent in supporting PDC eruption into the oral cavity and into a favorable position in the dental arch. Initial canine angulation and space assessments may be used as predictors of successful PDC eruption.

Stability of orthodontic treatment outcomes after 1-year treatment with the eruption guidance appliance in the early mixed dentition: A follow-up study.

OBJECTIVES: To investigate occlusal stability from the early mixed to the permanent dentition in children after early treatment with the eruption guidance appliance (EGA). MATERIALS AND METHODS: Of 46 participants who received 1-year early EGA treatment, 35 attended a follow-up examination at age 12. Group 1 (n = 21) started their EGA treatment at mean age 7.7 years, and group 2 at 9.1 years. Following 1-year treatment, the EGA was used as a retainer. Changes in overjet, overbite, sagittal molar relationship, and anterior crowding were measured on casts obtained before EGA treatment, after EGA treatment, and at follow-up to evaluate occlusal stability. RESULTS: Mean overjet, overbite, sagittal molar relation, and mandibular crowding improved significantly during the study period. Participants with good compliance during the retention period had significantly smaller overjet and overbite values than those with poor compliance. CONCLUSIONS: Early correction of increased overjet, overbite, and class II molar relation with the EGA is maintainable and can also be effective in the permanent dentition, provided the EGA is worn regularly as a retainer.

Does headgear treatment in young children affect the maxillary canine eruption path?

Objective: To test whether early headgear (HG) treatment and space conditions in the dental arch affect the eruption pathway of the maxillary canines in young children with mixed dentition. Subjects and methods: Data from two randomized controlled trials studying the effects of early HG treatment were pooled, yielding a study sample comprising 99 children (38 girls and 61 boys, mean age 7.6 years) with Angle Class II occlusion. Fifty-one children were treated with HG and 48 children served as an untreated control group (CG). Digital 3D models and panoramic radiographs were taken before (T0) and after (T1) treatment, and changes in the maxillary canine eruption angle and interdental spaces were measured at T0 and T1. A paired samples t-test was used to assess changes in maxillary canine angulation, and an independent samples t-test was used to evaluate the effect of HG treatment on spacing in the dental arch. Associations between intra-arch space conditions and changes in maxillary canine angulation were estimated with linear regression models. Results: The eruption pattern of the permanent canine was significantly more vertical in the HG group than in the CG. The linear regression models showed a statistically significant association among the intercanine distance, crowding in the anterior part of the maxilla, and changes in the maxillary canine eruption angle. The maxillary canine eruption pattern changed significantly more to a vertical direction in spaced dental arches than in crowded dental arches in the HG group. Conclusion: This study shows that early HG treatment in children with Angle Class II occlusion may change the eruption pattern of permanent maxillary canines to a more vertical direction. This change appears to be related to space conditions in the maxillary arch, especially in the intercanine region, with more effect in children with spaced dental arches than in children with crowded dental arches.

Stability of orthodontic treatment outcome in relation to retention status: An 8-year follow-up.

INTRODUCTION: Our aim was to evaluate the stability of orthodontic treatment outcome and retention status 7 or more years after active treatment in relation to posttreatment or postretention time, type of retention appliance, and duration of retainer use. METHODS: The subjects were former patients who completed orthodontic treatment with fixed appliances from 2000 to 2007. The pretreatment eligibility criteria were anterior crowding of 4 mm or more in the maxilla or the mandible and Angle Class I or Class II sagittal molar relationship. Acceptable pretreatment and posttreatment dental casts were required. A total of 67 patients participated, 24 men and 43 women, with a mean age of 24.7 years (range, 20.0-50.0 years). All participants had a follow-up clinical examination, which included impressions for follow-up casts, and each completed a questionnaire. Data were obtained from pretreatment, posttreatment, and follow-up (T2) casts as well as from the patients' dental records. Treatment stability was evaluated with the peer assessment rating (PAR) index and Little's irregularity index. RESULTS: The participation rate was 64%. The average posttreatment time was 8.5 years (range, 7.0-11.0). All participants had received a retainer in the mandible, maxilla, or both after active treatment. At T2, the PAR score showed a mean relapse of 14%. The majority (78%) of participants still had a fixed retainer at T2 (retainer group), and 22% had been out of retention for at least 1 year (postretention group). The relapse according to the PAR did not differ significantly between participants with and without a retainer at T2. From posttreatment to T2, the irregularity of the mandibular incisors increased almost 3 times more in participants with no retainer in the mandible compared with those with an intact retainer at T2 (P = 0.001). In the maxilla, no corresponding difference was found. CONCLUSIONS: Our results suggest that occlusal relapse can be expected after active orthodontic treatment irrespective of long-term use of fixed retainers. Fixed canine-to-canine retainers seem effective to maintain mandibular incisor alignment, whereas in the maxilla a fixed retainer may not make any difference in the long term.

Mode of correction is related to treatment timing in Class II patients treated with the mandibular advancement locking unit (MALU) appliance.

OBJECTIVE: To investigate the proportion of skeletal/dentoalveolar components for correction of Class II malocclusion in relation to the pubertal growth peak (PGP) among patients treated with the mandibular advancement locking unit (MALU) appliance. MATERIALS AND METHODS: We conducted a retrospective study of 27 orthodontic patients (age range: 12-18 years; mean age 14.9 years) with skeletal Class II Division 1 malocclusion who were treated with the MALU appliance until they reached Class I occlusion with overjet and overbite within normal range. Pretreatment (T1) and posttreatment (T2) lateral cephalograms were analyzed using standard cephalometrics and sagittal occlusion analysis to assess changes in the dentoalveolar and skeletal complex. The cervical vertebral maturation (CVM) method was used to determine participants' skeletal maturation in T1 cephalograms. Based on this maturation, participants were divided into two groups: the peak group (treatment initiation before or during PGP [peak group, n=15]) or the postpeak group (treatment initiation after the PGP [n = 12]). RESULTS: No significant differences between groups were found at T1 for most of the skeletal and dental parameters investigated. At T2, the mean ANB angle and proclination of the mandibular incisors were significantly smaller in the peak group than in the postpeak group. In the peak group, skeletal correction comprised 54% and dental correction 46% of the total change at T2, while in the postpeak group the corresponding figures were 24% and 76%, respectively. CONCLUSIONS: Treatment initiated before or during PGP seems to result in a more favorable SNA/SNB relationship and less tipping of the mandibular incisors than when treatment is initiated after PGP.

Root resorptions related to ectopic and normal eruption of maxillary canine teeth - A 3D study.

OBJECTIVE: To assess the incidence and severity of root resorption of maxillary incisors caused by ectopically and normally erupting maxillary canines and to analyse factors influencing root resorption of incisors using cone beam computed tomography. SUBJECTS AND METHODS: The study sample comprised 59 patients with a total of 80 canines. Forty-six of the canines, in 37 patients, were defined as ectopic and 34 canines, in 22 patients, were defined as normal. The severity of root resorptions were analysed according to studies by Ericson and Kurol. Multiple logistics regression was used to evaluate the association between various factors and root resorptions. RESULTS: The prevalence of root resorptions was significantly higher in the ectopic canine group, 11.0% of the central incisors and 67.6% of the lateral incisors in comparison to 0% and 36.2% in the normal erupting group. Most resorptions were defined as 'slight' and were located in the middle third of the root. There was a statistically significant relationship between canines located mesial to the midline of the lateral incisor and root resorption on the maxillary incisors. CONCLUSION: The present results show that root resorption of maxillary lateral incisors was common in patients referred to CBCT imaging due to maxillary canine eruption disturbances. Although significantly more frequent in patients with ectopically erupting canines, lateral incisor resorption was also found in association with approximately every third of the normally erupting canines. The best predictor for root resorption seemed to be location of the canine mesial in relation to the midline of the lateral incisor root.

One year treatment effects of the eruption guidance appliance in 7- to 8-year-old children: a randomized clinical trial.

BACKGROUND: The eruption guidance appliance (EGA) aims to correct sagittal and vertical occlusal relations concomitantly with alignment of the incisors. Few reports have been published on treatment effects with the EGA but no randomized studies have been available. OBJECTIVES: The aim was to find out if 1 year active treatment time with EGA was sufficient for achieving normal occlusal relationships and dental alignment in 7- to 8-year-old children. PARTICIPANTS, STUDY DESIGN, AND METHODS: Eligibility criteria for participants were: fully erupted upper central incisors, and Angle's Class I or Class II molar relationship combined with any of the following traits: deep bite, increased overjet ≥5mm, moderate anterior crowding with overjet ≥4mm. After screening of 148 children, 48 7- to 8-year-old children were recruited in the study. The participants were randomly assigned into a treatment group (N = 25) and a control group (N = 23). Children in the treatment group received treatment with the EGA for 1 year. The controls had no orthodontic treatment. Changes in overjet, overbite, Angle's Class, and crowding were used as primary outcome measures. Occlusal assessments were performed on dental casts obtained from all subjects at start of the study (T1) and after 1 year (T2). Lateral cephalograms were obtained from all subjects at T1 and from the treatment group at T2. All measurements on dental casts and cephalograms were carried out blinded. RESULTS: Forty-six children completed the study. Mean overjet and overbite decreased significantly in the treated subjects during 1 year, in contrast to a slight increase in the controls. Class II molar relationship decreased from 46 to 4 per cent in the treatment group, with no significant change in the control group. Mandibular anterior crowding decreased significantly in the treated subjects, while the controls showed a slight increase. CONCLUSIONS: In short term, the EGA seems to be effective in correcting increased overjet and overbite, Class II malocclusion, and lower anterior crowding in the early mixed dentition. Follow-up data are needed to assess long-term effects of this treatment. REGISTRATION: This study was not registered.

Outcome and long-term stability of an early orthodontic treatment strategy in public health care.

Our aim was to evaluate the long-term treatment outcome of a systematically applied orthodontic screening and early treatment strategy in a public dental health care system, with special reference to occlusal stability at least 5 years post-retention. The subjects (N = 68) belonged to one age cohort born in a Finnish rural municipality (N = 85), and they were regularly followed from 8 to 20 years. Persons with malocclusions were screened and treated according to pre-planned protocol. Treatment need was assessed according to the Dental Health Component of the Index of Orthodontic Treatment Need, and treatment outcome using the peer assessment rating (PAR) Index and Little's Index of Irregularity. Eighty-two per cent of the treated participants were out of retention (mean 6.9 years post-retention) at age 20. Definite treatment need in the study population decreased from 37% to 3 %. In the treated group, the mean PAR improvement decreased from 65 % to 63% from age 15 to 20 years. The mean irregularity score for the mandibular incisors was 4.0 [standard deviation (SD) 2.4] and for maxillary incisors 3.7 (SD 2.1) with no significant difference between treated and not treated subjects. The results suggest that definite need for orthodontic treatment may be predominantly eliminated from the target population with a systematically implemented treatment strategy focusing on early treatment with simple appliances. Emphasis on early timing of treatments may have contributed to the good long-term stability of treatment results.

Nickel sensitization in orthodontically treated and non-treated female adolescents.

BACKGROUND: The importance of the nickel exposure from fixed orthodontic appliances is under continuous discussion. OBJECTIVES: Our aim was to investigate nickel allergy and the risk of nickel sensitization among female adolescents during orthodontic treatment with fixed appliances as compared with non-treated female adolescents. SUBJECTS AND METHODS: Female patients starting or with ongoing orthodontic treatment (n = 30) and young females without a history of orthodontic treatment (n = 140) were studied. Patch testing with 5% nickel sulfate was carried out twice on each participant with an approximately 1-year interval. The subjects completed a questionnaire before the first testing. RESULTS: None of the 7 orthodontic patients with a positive patch test reaction to nickel had any clinically visible intraoral allergic symptoms during their treatment. No significant difference was seen in the occurrence of positive nickel reactions in regard to orthodontic treatment, or between the first and second tests. In the treatment group, 2 patients changed from nickel-positive to nickel-negative during the observation period, and one patient showed an opposite change. The quantity and course of changes in the repeated nickel patch test reactions did not differ significantly between the subjects with and without orthodontic treatment experience. CONCLUSIONS: Nickel sensitization from orthodontic appliances is improbable, but nickel sensitization may develop also during orthodontic treatment.

Face and neck dermatitis from a stainless steel orthodontic appliance.

Although nickel is the most common cause of contact allergy, nickel-containing orthodontic appliances seldom cause adverse reactions that result in discontinuation of treatment. We report on an eruption of dermatitis in the face and neck of an adult female patient after placement of a rapid maxillary expansion appliance (RME). Because the patient suspected nickel allergy, her tolerance to the appliance material was tested intraorally before treatment by cementing bands on four teeth for a week. No visible adverse reactions were seen during the test. One week after cementation of the RME appliance, the patient reported strong itching of the face and a red rash. Clinical examination showed itchy papular erythema on the face and neck. No intraoral reactions or symptoms were present. The RME appliance was removed, and symptoms disappeared in 4 to 5 days. The patient was referred for a nickel patch test, which gave a strong positive result. Adverse patient reactions of potential allergic origin should be diagnosed carefully, and their possible impact on further treatment should be evaluated accordingly.

Adverse patient reactions during orthodontic treatment with fixed appliances.

INTRODUCTION: Our aims in this study were to assess adverse patient reactions during orthodontic treatment with nickel-containing appliances and to investigate the need for and the use of nickel-free devices in orthodontic practices in Finland and Norway. METHODS: A questionnaire was mailed to orthodontists and dentists versed in orthodontics in both countries. They were asked to retrospectively assess the number of patients with adverse reactions and to describe the reactions, the appliances used, and any implications on treatment. Previous history of nickel allergy of patients with adverse reactions, and use of and need for nickel-free appliances in clinical practice were also addressed. RESULTS: Forty-six percent of the respondents (n = 298) reported at least 1 adverse patient reaction during the last 5 years. More than half of the reactions had implications for the treatment. Finnish respondents observed significantly more adverse patient reactions than their Norwegian colleagues, and, in Finland, the adverse reactions were most frequently attributed to headgear treatment. Using nickel-containing fixed appliances in nickel-allergic patients was more common in Finland (77% of the respondents) than in Norway (65%). CONCLUSIONS: Nearly half of the dentists regularly working with fixed appliances had observed at least 1 adverse patient reaction during treatment. Nickel-containing fixed appliances are generally used in most patients-even those with a suspected nickel allergy.

Residual need for early orthodontic treatment and orthodontic treatment experience among 13- to 14-year-old school children in Kuwait.

OBJECTIVE: Our purpose was to determine the residual need for early orthodontic treatment and the parameters associated with orthodontic treatment experience in 13- to 14-year-old school children in Kuwait. SUBJECTS AND METHODS: A total of 788 boys and 795 girls, representing about 6.7% of the target population, were selected according to cluster sampling methods. Information on nationality, family income and orthodontic treatment experience was collected through subject and family interviews. The occlusal morphology was recorded in a well-lit classroom or from initial study models of subjects with orthodontic treatment experience. RESULTS: Only 6.7% of the 225 subjects with early treatment need, defined as overjet >or=6.5 mm, and functional posterior and anterior crossbite on 1 or more teeth, had treatment experience. Residual need for early treatment was present in 13.4% of the subjects. Only 26.8% of the subjects with treatment experience met our criteria for early treatment need. The odds of treatment experience were higher in the subjects attending private schools (p < 0.05), in those from families with an income of KWD >2,000 (USD 6,600; p < 0.01) and in subjects meeting the criteria for early treatment need (p < 0.01). CONCLUSIONS: About 15% of each birth cohort of school children in Kuwait need early orthodontic treatment. Less than 10% of those with a need have treatment experience at 13-14 years of age, and about 75% of those with treatment experience at that age do not need early treatment. The predictors for treatment experience at 13-14 years of age are private-school attendance, a high family income and need for early treatment.

Prevalence and severity of malocclusion in adolescent Kuwaitis.

OBJECTIVES: Our aim was to evaluate prevalence and severity of malocclusion in an adolescent Kuwaiti population. SUBJECTS AND METHODS: Using a stratified cluster sampling method and excluding non-Kuwaitis, subjects with mesial migration and/or loss of first molars, and subjects with orthodontic treatment experience without availability of initial study models, we examined 1,299 Kuwaitis (674 boys and 625 girls) of mean age 13.2 +/- 0.4 years in a regular well lit classroom. We scored molar and canine relationship, overjet, overbite, anterior and posterior cross bite as well as spacing and irregularity of the incisors using gloves, mirrors, rulers, and spatulas. RESULTS: Fourteen, 15, and 71% met the criteria for almost ideal, mild, and moderate to severe malocclusion, respectively. Of the 86% with malocclusion, occurrence of class 1, half step class 2, full step class 2, half step class 3, and full step class 3 was 57.8, 24.9, 6.3, 8.8, and 2.2% for the first molars, and 36.1, 50.0, 6.2, 5.4, and 2.3% for the canines, respectively. Incisor malalignment was the most prevalent malocclusion trait (73.2%). Overjet > or = 9.5 mm occurred in less than 1.5%, open bite in less than 3.5%, deep bite with gingival contact in less than 2.0%, complete posterior cross bite in less than 1.5%, and complete anterior crossbite in less than 2.0%. Median diastema was present in about 2/3 of the cases with maxillary anterior spacing as opposed to only about 1/3 of those with mandibular spacing. CONCLUSION: Our findings suggest that more than 70% of young adolescent Kuwaitis have moderate to severe malocclusion, with incisor malalignment as the most prevalent malocclusion trait.

Incisor trauma in an adolescent Arab population: prevalence, severity, and occlusal risk factors.

INTRODUCTION: Incisor trauma is a significant clinical problem in children and adolescents. The purposes of this study were to report on the prevalence and severity of incisor trauma in a large population-based sample of adolescent Kuwaiti residents in the early permanent dentition, to determine the ages of and reasons for the injuries, and to test for any effects of sex, incisor occlusion, and lip coverage on the prevalence of incisor trauma. METHODS: Presence and type of traumatic injury were scored according to the National Institute of Dental Research index in a population-based sample of 795 girls and 788 boys with a mean age of 13.24 years (SD 0.42). RESULTS: Trauma prevalence was higher (P < .001) in boys (19.3%) than in girls (9.7%), and in the maxilla (13.6%) than in the mandible (1.5%). Most (77.3 %) of the affected subjects had only 1 injured tooth, and most (83.7%) of the traumatized teeth were maxillary central incisors. A total of 90.3% of the injuries were unrepaired enamel or enamel/dentin fractures. The major reasons for the injuries were falls and blows indoors (48.4%) or outdoors (41.6%). Nearly two-thirds (63.0%) of the traumas occurred at age 10 years or later. Mean overjet (OJ) was larger (3.9 v 3.0 mm, P < .01), and lip incompetence more frequent (12.7% v 7.3%, P < .01) among the subjects with injured maxillary incisors than among those without. Logistic regression showed that the odds of maxillary incisor trauma were 2.8 times higher in subjects with OJ between 6.5 and 9.0 mm, and 3.7 times higher in subjects with OJ > or = 9.5 mm than in subjects with OJ < or = 3.5 mm. CONCLUSIONS: Multiple logistic regression showed that the risk of maxillary incisor trauma was about 2 times higher in boys than in girls, and that the risk increased by 13% for every millimeter of increase in OJ. Lip competence was not included in the model. No associations were found between occlusion and mandibular incisor trauma.

Orthodontic treatment need from eight to 12 years of age in an early treatment oriented public health care system: a prospective study.

The aim of this study was to investigate the effects of an early treatment oriented orthodontic program on treatment need at age 12 years in a public health care system. The subjects consisted of one whole age cohort in a municipality in Finland, 87 children in total. All children were examined at ages eight, 10, and 12 years. Treatment need was assessed on casts using a modified Dental Health Component of the Index of Orthodontic Treatment Need and a 10-Grade Scale based on the Treatment Priority Index. Early treatment was started on children having definite treatment need according to both indices. The agreement between indices was good at ages eight and 12 years and moderate at age 10 years. Treatment need changed significantly from eight to 12 years. Of the 29 children with definite treatment need at age eight years, only two had treatment need at age 12 years. Of the 38 children with no treatment need at age eight years, 28 remained in this category and only two children had definite need for treatment at age 12 years. The duration of treatment ranged from one to 61 months, although 59% of the treatments lasted two years or less. We conclude that systematically planned early orthodontic treatment may have contributed to the significant reduction in treatment need from eight to 12 years of age.

Association between normative and self-perceived orthodontic treatment need among Arab high school students.

The aim of this study was to investigate whether there was an association between normative and self-perceived orthodontic treatment need, and to evaluate the influence of sex and socioeconomic background on treatment need. A total of 139 high school students, aged 14 to 18 years, from 2 districts in Kuwait were included. The study consisted of a questionnaire and a clinical examination. Normative need for treatment was assessed clinically by using the index of orthodontic treatment need (IOTN). Both the dental health component (DHC) and the aesthetic component (AC) of the IOTN correlated positively with self-perceived treatment need. In 53% of the subjects, there was agreement between self-perceived treatment need and the DHC score. Between the AC component and self-perceived need, the agreement was 77%. The odds of self-perceived treatment need were 10-fold for subjects having AC scores higher than 4, indicating moderate or definite need. Sex and socioeconomic factors did not significantly affect the normative treatment need. These results suggest that the AC component of the IOTN clearly reflects the self-perceived need for treatment.

The role of prevention and simple interceptive measures in reducing the need for orthodontic treatment.

The purpose of the interceptive orthodontic treatment is to eliminate or reduce the need for treatment in the permanent dentition. The major advantage of such a treatment may also be that it is technically simple and relatively cheap, compared to comprehensive treatment with full fixed appliances. The need for interceptive measures to avoid adverse occlusal and dental consequences, which are effects of the early loss of primary molars and nonnutritive sucking habits, is discussed. The need for prevention and early intervention in patients with anterior open bites, posterior functional crossbites and signs of ectopic erupting canines is also discussed.

Subjective need and orthodontic treatment experience in a Middle East country providing free orthodontic services: a questionnaire survey.

The aims of this study were to explore orthodontic treatment experience, subjective need for treatment, and perceptions of teeth and dental appearance in relation to background factors such as funding system, area of living, age, gender, ethnicity, and socioeconomic status. The subjects were 1076 randomly selected second-year high school students from a rural (Jahra) and an urban (Capital) area of Kuwait, with a mean age of 15.1 years. Kuwaiti citizens constituted 79% of the sample, and the rest were of other Arab origins. The data were collected using a questionnaire. Orthodontic treatment rate was significantly higher for Kuwaitis (10%) than for non-Kuwaitis (2%). Among Kuwaiti subjects, urban area of living and female gender increased the odds of receiving orthodontic treatment. Subjective treatment need was 36%, with no difference between Kuwaiti and non-Kuwaiti subjects, but Kuwaitis in the rural area expressed subjective treatment need less often than those in the urban area. The results suggest that access to free-of-cost orthodontic treatment was likely to affect treatment rate, whereas it did not seem to influence the self-perceived need for treatment. Gender and area of living may be significant for the distribution of free-of-cost orthodontic treatment.