OBJECTIVE: To assess whether different levels of malocclusion have different effects on the oral health-related quality of life (OHRQoL) and which domains of OHRQoL could be affected.
METHODS: Nine electronic databases were searched. To make studies comparable, studies using the Child Perceptions Questionnaire (CPQ) to measure OHRQoL, and the Dental Aesthetic Index, Index of Orthodontic Treatment Need, and Index of Complexity, Outcome and Need to measure malocclusion were selected for systematic review. Meta-analysis was performed to calculate the weighted mean scores of CPQ. The two independent samples t-test was used to detect whether different severity groups of malocclusion have different CPQ scores.
RESULTS: A total of 22 studies were included in this review and 6 were included in the meta-analysis. Most studies used a cross-sectional design and convenience sampling. Meta-analysis showed that the weighted mean scores of CPQ increased with malocclusion severity. The t-test showed nearly all levels of malocclusion affected the domains of functional limitation and social well-being; only very severe malocclusion affected the domains of oral symptoms, emotional well-being and the overall OHRQoL (p < 0.05).
CONCLUSIONS: When OHRQoL was assessed by CPQ11-14 and malocclusion was assessed by orthodontic indices, children with malocclusion could have oral functional limitations and worse social lives; children with very severe malocclusion could further develop oral symptoms and had worse emotional experiences. Future longitudinal population-based studies would be helpful to confirm these results.

UNASSIGNED: Malocclusion is a common oral health problem and can affect the psychosocial well-being in the long term. Therefore, in the recent decades, demand for orthodontic treatment to correct malocclusion has greatly increased worldwide. This systematic review and meta-analysis was undertaken to assess existing evidence on the prevalence of orthodontic treatment need in Iran.
UNASSIGNED: National and international databases were searched for articles on the prevalence of orthodontic treatment need using index of orthodontic treatment need (IOTN) and dental aesthetic index (DAI). The required data were completed by hand-searching. After applying the inclusion and exclusion criteria, the quality of articles was checked by a professional checklist. Data extraction and meta-analysis were performed. A random effects model was employed, and publication bias was checked.
UNASSIGNED: From a total of 443 articles that reported orthodontic treatment need in Iran, 24 articles were included in the meta-analysis process. Meta-analysis was performed on components of IOTN and DAI. The pooled prevalence of orthodontic treatment need based on Dental Health Component and Aesthetic Component of IOTN and DAI was 23.8% (19.5%-28.7%), 4.8% (3.3%-7%), and 16.1% (12.3%-20.8%). The results were found to be heterogeneous (P < 0.05).
UNASSIGNED: The results of this study revealed that orthodontic treatment need was not high in the Iranian population. Considering the differing prevalence of orthodontic treatment need based on normative index and self-perceived index, it is essential to improve the people\'s awareness of malocclusion and its side effects on their oral and general health.

The aim of this study was to identify and summarize the outcomes measured in orthodontic studies of children with cleft lip and/or palate. The objectives were to categorize the outcomes into pre-determined domains and to explore whether any domains were under-represented. Electronic databases and grey literature were searched until December 2016 to identify all studies of orthodontic treatment interventions in children and adolescents with cleft lip and palate. Abstracts and subsequently eligible full-text articles were screened independently and in duplicate by two reviewers. All reported outcome measures were identified and categorized into six predetermined outcome domains. The search identified 833 abstracts. The majority of studies did not assess orthodontic interventions and were therefore not eligible for inclusion. Consequently, following screening 71 eligible articles were retrieved in full, of which 40 met the inclusion criteria. Morphological features of malocclusion were measured in 27 studies (68%) and adverse effects of orthodontic treatment in 10 (25%). Functional status (n=4; 10%), physical consequences of malocclusion (n=3; 7.5%), quality of life (n=3; 7.5%) and health resource utilization (n=2; 5%) were rarely considered. Relatively few studies concerning patients with cleft lip and palate focused on orthodontic interventions. Most of the identified outcomes were concerned with measuring morphological treatment-related changes and do not reflect patient perspectives.

OBJECTIVE: To date, there is no evidence-based method of quantification for malocclusion. Consequently, how deviant occlusal traits should be scored and weighted relative to one another is a matter of serious debate. Orthodontic Treatment Need Indices (OTNI) use the subjective opinion of the experts, as their foundation, to define the pathological boundaries (cut-offs) of occlusal traits. This paper reviews the evidence relating malocclusions or deviated occlusal traits to oral health problems, and investigates if this evidence supports the cut-off points and the rationale used for OTNI.
METHODS: The relevant cited studies and reviews from the MEDLINE, Web of Science, Scopus, Cochrane databases, and scientific textbooks were used. The citation rate was confirmed by using the Google Scholar.
RESULTS: So far, the evidence for harmful effects of deviated occlusal traits on oral health is either lacking or exists as cross-sectional (mostly) and longitudinal (a few and primarily short-term) studies. When an association was reported between a deviated occlusal trait and an oral health problem, either the strength of that association was weak, or due to methodological issues, findings were not conclusive. Consequently, establishing a cause and effect relationship is difficult. Further, commonly used OTNI do not record a full spectrum of occlusal traits, and relating their ranking or scoring systems to the available evidence is difficult. Therefore, there is little evidence to suggest that individuals with a high need (high score), as measured by OTNI, will necessarily put at risk their oral health if they turn down orthodontic therapy.
CONCLUSIONS: OTNI have a role in the epidemiology and can be used for resource planning, but their predictive value to detect the future objective functional deficits or oral health problems is questionable. OTNI will need revalidation over time with emerging research findings.

OBJECTIVE: Aesthetic improvement and psychological enhancement have been cited as justifications for orthodontic treatment. This paper reviews the evidence that relates malocclusion to psychological health and quality of life and explores whether this evidence supports the most commonly used aesthetic Orthodontic Treatment Need Indices (OTNI).
METHODS: The relevant cited material from the MEDLINE, Web of Science, Scopus, Cochrane databases, and scientific textbooks were used. The citation rate was confirmed by using the Google Scholar.
RESULTS: The subjective nature of aesthetic indices and the variable perception of attractiveness between clinicians and patients, and among various cultures or countries are a few limitations of aesthetic OTNI. The available evidence of mainly cross-sectional studies on the link between malocclusion and either psychosocial well-being or quality of life is not conclusive, and sometimes contradictory, to suggest these characteristics are affected by malocclusions. Further, the long-term longitudinal studies did not suggest that people with malocclusion are disadvantaged psychologically, or their quality of life would be worse off, which challenges using aesthetic OTNI to assess the social and psychological implications of malocclusion.
CONCLUSIONS: The subjective nature of aesthetic OTNI and the minor contributory role of malocclusion in psychosocial health or quality of life undermine using aesthetic indices to assess the likely social and psychological implications of malocclusion. Consequently, using aesthetic OTNI, as a method to quantify malocclusion remains open to debate. Various soft and hard-tissue analyses are used before formulating a treatment plan (i.e., assessment of sagittal and vertical skeletal relationships). The addition of a shortened version of these analyses to the aesthetic OTNI can be a good substitute for the aesthetic components of OTNI, if an assessment of the aesthetic aspects of malocclusion is intended. This reduces subjectivity and improves the validity of the OTNI that incorporate an aesthetic component.