Longitudinal trends in temporomandibular joint disorder symptoms, the impact of malocclusion and orthodontic treatment: A 20-year prospective study.

BACKGROUND: Studies on the association between malocclusion and temporomandibular joint disorder (TMD) have reported conflicting results. OBJECTIVES: To determine the impact of malocclusion and orthodontic treatment on symptoms of TMD. METHODS: At 12 years, 195 subjects fulfilled a questionnaire regarding TMD symptoms and participated in an oral examination including preparation of dental casts. The study was repeated at ages 15 and 32. The occlusions were assessed by applying the Peer Assessment Rating (PAR) Index. Associations between the changes in PAR scores and TMD symptoms were analysed with the chi-square test. A multivariable logistic regression was used to calculate the odds ratios (OR) and 95% confidence intervals (CI) of TMD symptoms at 32 years predicted by sex, occlusal traits and orthodontic treatment history. RESULTS: One in three subjects (29%) was orthodontically treated. Sex was associated with more self-reported headaches by females at 32 years (OR 2.4, 95% CI 1.05-5.4; p = .038). At all time points, any crossbite was significantly associated with greater odds for self-reported temporomandibular joint (TMJ) sounds at 32 years (OR 3.5, 95% CI 1.1-11.6; p = .037). More specifically, association occurred with posterior crossbite (OR 3.3, 95% CI 1.1-9.9; p = .030). At 12 and 15 years, boys whose PAR score increased were more likely to develop TMD symptoms (p = .039). Orthodontic treatment had no impact on the number of symptoms. CONCLUSIONS: Presence of crossbite may increase the risk of self-reported TMJ sounds. Also, longitudinal changes in occlusion may have an association with TMD symptoms while orthodontic treatment is not associated with the number of symptoms.

Long-term (≥15 years) post-treatment changes and outcome quality after Class II:1 treatment in comparison to untreated Class I controls.

Aim: To investigate the long-term (≥15 years) post-treatment (Tx) occlusal changes and outcome quality after Class II:1 Tx. Subjects and Methods: Herbst-MBA Tx had been performed at age 12.8 ± 2.7 years in 119 patients. A recall was conducted and study models from before and after active Tx, after retention as well as after recall were evaluated using standard occlusal variables and the PAR index. These data were compared to 31 untreated Class I controls. Results: 52 out of 119 patients could be located and participated at 33.6 ± 3.1 years. Compared to the 67 patients who did not participate in the recall, the pre- and post-Tx occlusal data of the participants did not differ systematically; however, the PAR scores were higher by 3.0-4.7 points at all times. Pre-Tx, the mean values of the 52 participants were: PAR = 27.2 ± 7.6, Class II molar relationship (MR) = 0.7 cusp widths (cw), overjet = 8.2 mm, overbite = 4.1 mm. After Tx, the PAR score was 3.4 ± 2.2. A Class I MR (0.0 ± 0.1 cw) with normal overjet (2.3 ± 0.7 mm) and overbite (1.3 ± 0.7 mm) existed. At recall, a mild PAR score increase to 8.2 ± 5.5 points had occurred; this was mainly due to increased overjet and overbite values (3.6 ± 1.1 and 2.8 ± 1.6 mm) while the MR was stable (0.0 ± 0.2 cw). For all these variables, similar findings were made in the untreated controls. Conclusion: The occlusal outcome of Class II:1 Tx showed very good long-term stability. While mild changes occur post-Tx, the long-term result is similar to untreated Class I controls.

Outcome quality and long-term (≥15 years) stability after Class II:2 Herbst-multibracket appliance treatment in comparison to untreated Class I controls.

Aim: To investigate the outcome quality and the long-term (≥15 years) post-treatment (Tx) changes after Class II:2 Herbst-multibracket appliance (MBA) Tx. Subjects and Methods: In this longitudinal observational study, a recall of Class II:2 patients who had been treated by a Herbst-MBA during adolescence was conducted. Study models from before and after active Tx, after retention and after recall were assessed using standard occlusal variables and the peer assessment rating index (PAR). These data were compared to historical untreated Class I controls. Results: Twenty out of 33 patients (61%) could be located and participated at age 33.9 ± 2.7 years. When comparing their data to the 13 patients who did not participate, the pre- and post-Tx occlusal findings did not differ systematically; however, the PAR scores of the non-participants were by 3.3-8.2 points higher at all times and the non-participants were 2.1-2.5 years older. Pre-Tx at age 14.4 ± 2.7 years, the participants showed the following mean values: PAR = 15.0 ± 7.0, Class II molar relationship (MR) = 0.8 ± 0.3 cusp widths (cw), overbite = 5.3 ± 1.3 mm. After Tx, a PAR score of 2.9 ± 1.3 and a super Class I MR (-0.1 ± 0.1 cw) with normal overbite (1.2 ± 0.8 mm) existed. At recall, a PAR score increase to 5.9 ± 3.6 points had occurred, mainly caused by an increase of overbite to 2.5 ± 1.5 mm. The average MR remained Class I (0.0 ± 0.2 cw). For all variables, the untreated controls exhibited similar findings. Conclusion: The occlusal outcome of Class II:2 Herbst-MBA Tx exhibited very good long-term stability. While mild post-Tx changes occurred, the long-term findings are similar to untreated Class I controls.

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.

The objective and subjective outcome of orthodontic care in one municipal health center.

OBJECTIVE: The aim of this study was to assess the outcome of orthodontic care in one municipal health center. MATERIALS AND METHODS: The material consisted of one age-cohort of 15-16 year-old adolescents (n = 67). Of them, 97% participated in a clinical examination. The final group included in the study consisted of 61 adolescents (91% of the whole age cohort). The occlusions were evaluated applying the Occlusal Morphology and Function Index (OMFI), the Dental Health Component (DHC) and the Aesthetic Component (AC) of the Index of Orthodontic Treatment Need (IOTN). Moreover, all adolescents filled in a semi-structured questionnaire enquiring about their satisfaction with the function and appearance of their own dentition and self-perceived orthodontic treatment need. They also scored their own dental appearance on a Visual Analog Scale (VAS). RESULTS: Of the adolescents, 42% had received orthodontic treatment, while 58% were untreated. All morphological criteria of the OMFI were met by 58% of orthodontically treated and 49% of untreated adolescents and all functional criteria by 67% and 57%, respectively. Treatment need was registered in two of the treated adolescents (7%) and five of the untreated adolescents (14%). Treated adolescents were more often satisfied with their dental appearance than untreated adolescents (p = 0.034). In both groups, satisfaction with the function was high (93%). CONCLUSIONS: Orthodontic treatment seems to improve both occlusal morphology and function. The high satisfaction with one's own dental appearance among the treated adolescents is worth noting.

Dental arch width, overbite, and overjet in a Finnish population with normal occlusion between the ages of 7 and 32 years.

The aims of the present study were to provide data on growth changes in the dental arches from age 7 to 32 in Finns with untreated normal Angle Class I occlusions. The material consisted of 33 series of dental casts of 18 women and 15 men. The subjects had been examined and study models taken at the ages of 7, 10, 12, 15, and 32. Dental arch width, overbite, and overjet were measured. Our longitudinal findings show that both the dental arches of young adults are slightly narrowed from adolescence to 32 years of age. All increases in width dimensions took place before 15 years of age. The means of the changes were mostly small, in the order of 0.5 to a few millimetres. Variability in age changes was considerable. In both genders, each variable increased in some subjects and decreased in others during every age interval. Differences between growth changes in the mesial, distal, and gingival intermolar widths indicate that both the maxillary and the mandibular first molars rotate mesiolingually and that the maxillary first molars also become more upright during late occlusal development. We expect the present findings of the changes occurring in the arch dimensions of subjects with untreated normal occlusions to help clinicians in following up occlusal development, choosing an optimal treatment time, and making orthodontic treatment and retention plans. However, because of the wide variability, accurate prediction of future development cannot be made on the individual level.

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.