Relationship between malocclusion and maintenance of teeth

The consequences of living with a severe malocclusion: A review of the literature

AIM

To facilitate the orthognathic shared decision-making process by identifying and applying existing research evidence to establish the potential consequences of living with a severe malocclusion.

METHODS

A comprehensive narrative literature review was conducted to explore the potential complications of severe malocclusion. A systematic electronic literature search of four databases combined with supplementary hand searching identified 1024 articles of interest. A total of 799 articles were included in the narrative literature review, which was divided into 10 themes: Oral Health Related Quality Of Life; Temporomandibular Joint Dysfunction; Masticatory Limitation; Sleep Apnoea; Traumatic Dental Injury; Tooth Surface Loss; Change Over Time; Periodontal Injury; Restorative Difficulty; and Functional Shift and Dual Bite. A deductive approach was used to draw conclusions from the evidence available within each theme.

RESULTS

The narrative literature review established 27 conclusions, indicating that those living with a severe malocclusion may be predisposed to a range of potential consequences. With the exception of Oral Health Related Quality Of Life, which is poorer in adults with severe malocclusion than those with normal occlusions, and the risk of Traumatic Dental Injury, which increases when the overjet is >5 mm in the permanent and 3 mm in the primary dentition, the evidence supporting the remaining conclusions was found to be of low to moderate quality and at high risk of bias.

CONCLUSION

This article summarises the findings of a comprehensive narrative literature review in which all of the relevant research evidence within a substantive investigative area is established and evaluated. Notwithstanding limitations regarding the quality of the available evidence; when combined with clinical expertise and an awareness of individual patient preferences, the conclusions presented may facilitate the orthognathic shared decision-making process and furthermore, may guide the development of the high-quality longitudinal research required to validate them.

Dental crowding as a caries risk factor: a systematic review

INTRODUCTION

The association between dental crowding and dental caries has long been accepted because of increased food accumulation and plaque retention in areas of crowding. The aim of this review was to evaluate this potential causal relationship systematically.

METHODS

Six electronic databases were accessed, supplemented by manual searching of the references of the relevant retrieved articles, peer-reviewed orthodontic journals, and gray literature. Search terms included caries, decay, crowding, and irregularity. Non-English articles were excluded from the review in the study-selection stage. Data extraction and evaluation of primary studies were performed independently by 2 reviewers.

RESULTS

The initial search retrieved 6914 citations. However, only 18 articles met the inclusion criteria. The qualitative systematic review included 8 studies, with articles of low or moderate quality. No association between crowding and caries was reported in 4 studies, a significant negative correlation was found in 2 studies, 1 study showed a direct and significant relationship, and another study showed a positive association in the mandibular anterior region but an inverse correlation in the maxillary posterior region.

CONCLUSIONS

To date, there are no high-quality studies to resolve the possible association between dental crowding and caries; further high-quality longitudinal studies are needed to clarify this relationship.

The development of the index of complexity, outcome and need (ICON)

This paper is based on the winning submission for the 1998 Chapman prize awarded by the British Orthodontic Society for an essay on a subject promoting the interests of orthodontics. The aim of the investigation is to develop a single index for assessing treatment inputs and outcomes. An international panel of 97 orthodontists gave subjective judgements on the need for treatment, treatment complexity, treatment improvement, and acceptability on a diverse sample of 240 initial and 98 treated study models. The occlusal traits in the study models were scored according to a defined numerical protocol. Five highly predictive occlusal traits were identified (IOTN Aesthetic Component, crossbite, upper arch crowding/ spacing, buccal segment antero-posterior relationships, and anterior vertical relationship) and then used to 'predict' the panelist's decisions using regression analysis. Cut-off values were determined for the dichotomous judgements by plotting specificity sensitivity and overall accuracy. Twenty percentile ranges were used to determine 5 grades of complexity and improvement. The index prediction of decisions for treatment need, had specificity 84.4 per cent, sensitivity 85.2 per cent, and overall accuracy 85 per cent. When used to predict treatment outcomes, the new index had specificity 64.8 per cent, sensitivity 70.1 per cent, and overall accuracy 68.1 per cent. The index could explain 75.6 per cent of the variance in the mean casewise complexity score and 63.5 per cent of the mean casewise improvement score. A new orthodontic index is proposed to assess treatment need, complexity, and outcome. It is based on international orthodontic opinion.

Adult patients' view of orthodontic treatment outcome compared to professional assessments

One important aspect in evaluating the outcome and quality of orthodontic treatment is the patient's own assessment. The objective of this study was to evaluate the course and outcome of orthodontic treatment in adults from the patient's vs the operator's point of view. In a previous study, the orthodontic treatment of 88 adults was evaluated using the IOTN and PAR Index before and after treatment. Fifty-nine patients answered treatment questionnaires on 1. the reason for seeking treatment, 2. dentofacial aesthetics, 3. treatment outcome, 4. course of treatment, 5. attitude, 6. social well-being. Depending on the original treatment goal, the patient population was divided into an Ideal Group and a Compromise Group. In 75% of the patients, dissatisfaction with dental aesthetics was the prime motive for seeking treatment; correlations with PAR parameters (overjet and maxillary anterior teeth) were weak. In general, a high degree of patient satisfaction with orthodontic treatment was registered. As regards satisfaction with post-treatment dental aesthetics there were no significant differences between the groups. Comparison of professional assessment with the subjective rating by patients revealed discrepancies in that the patients' rating of outcome tended to be more positive. The differentiation between ideal and compromise treatment goals proved useful. In the Compromise Group, a high level of patient satisfaction was attained with a shorter treatment duration and lower appliance involvement. 92% considered their major pre-treatment need to have been met, and 95% would have had the treatment performed again.

Periodontal diagnosis in treated periodontitis. Why, when and how to use clinical parameters

The objective of clinical periodontal diagnosis in maintenance patients is to monitor the risk for periodontal disease progression. Risk for progression should be continuously monitored at the patient, tooth and site level at each recall appointment. At the patient level, the significance of systemic diseases, cigarette smoking, compliance with the recall program, loss of support in relation to the patient's age, full mouth plaque and/or bleeding scores, and prevalence of residual pockets are of key importance. At the tooth and tooth-site levels, residual periodontal support, inflammatory parameters and their persistence, presence of ecological niches with difficult access such as furcations, and presence of iatrogenic factors have to be put into proportion with the patient's overall risk profile. The information gathered by clinical monitoring and continuous multilevel risk assessment facilitates an immediate appreciation of the periodontal health status of an individual and the possible risk for further infection and/or disease progression in the dentition and at a particular tooth or site.

[The psychosocial aspects in orthodontically treated and untreated adults with similar, clearly visible tooth malalignments]

A study was undertaken to compare the psychosocial aspects of orthodontic treatment or non-treatment of female adults, 25 of whom underwent treatment and 25 of whom did not, with similar, visible malocclusion. Interviews, for which 52 standardized questions were prepared in collaboration with a graduate psychologist, served as the methodological basis of the study. The results of the study indicate that in relation to the aesthetic aspects of orthodontic treatment, the treated group showed a high degree of sensitivity and self perception. Following orthodontic treatment members of this group exhibited a highly significant improvement in their subjective perception of the aesthetic aspects of their dental and facial appearance. In spite of the differences observed in the 2 groups, it nevertheless remains difficult to draw general conclusions or to recommend guidelines which would cover all cases. When the question is to orthodontically treat or not treat female adults, the answer rests with the individual patient.

The prevalence and severity of malocclusion and the need for orthodontic treatment in 9-, 12-, and 15-year-old Glasgow schoolchildren

An epidemiological investigation involving 765 Glasgow schoolchildren aged nine, twelve, and fifteen years was undertaken to assess the severity of malocclusion, the need for orthodontic treatment, and the proportion of children in each age group who had previously received treatment. An index termed the Malocclusion Severity Index (MSI) was developed to establish objectively the severity of malocclusion in each individual. Fifty sets of orthodontic study models and six orthodontists assessed the reproducibility and validity of the index. Although there was a significant reduction in the proportion of children in need of orthodontic treatment between 9 and 15 years of age, a considerable number were still in need of treatment; crowding of their dentitions being responsible for the majority of the treatment requirement. The MSI was found to be as precise and valid as previously developed occlusal indices, for estimating the treatment needs of sample populations.

Perception of personal dental appearance in young adults: relationship between occlusion, awareness, and satisfaction

Information about the individual perception of a patient's own occlusion is considered of importance in orthodontics. One hundred thirty young adults (mean age, 18.1 years) were clinically examined and interviewed with the purpose of relating self-awareness and satisfaction to the actual occlusal status and determining whether dissatisfaction is based on realistically perceived anomalies. From study casts taken at the time of examination, six anterior traits were recorded as either malocclusion, minor deviation, or near-ideal occlusion according to two sets of criteria. Self-awareness was assessed by analyzing agreement between the subjects' reports on the presence of the six traits and the corresponding recordings. Satisfaction was evaluated from three questions with fixed alternative answers. The majority of the young adults (63%) were characterized as having near-ideal occlusion or only minor deviations. Only mild and moderate malocclusions were present in the sample since severe malocclusions are routinely treated during childhood. The subjects were generally aware of anterior traits. Almost all the subjects (98%) with near-ideal occlusion or minor deviations expressed satisfaction. Malocclusion was present in 14 of the 16 subjects who were dissatisfied, and dissatisfaction was based on realistically perceived anomalies. However, traits rated as malocclusion were present in 30% of the satisfied subjects, which may in part be explained by the mild degree of malocclusion in the sample. Awareness of occlusal traits varied among the satisfied subjects.

Causal relation between malocclusion and periodontal health

The purpose of this 20-year follow-up study was to assess whether persistent traits of morphologic malocclusion imply an increased risk of periodontal disease. In 1965-66 malocclusion was recorded in 176 adolescents who were re-examined in 1986-87 at the age of 33-39 years. Markedly healthier periodontal conditions were found in women than men, in the higher social group than the lower one, and in the maxilla than the mandible. Subjects with specified malocclusion traits at both examinations were compared with subjects without malocclusion for the occurrence of calculus, gingivitis (bleeding), and pocketing. Controlling for the effect of sex and social group, periodontal disease was significantly more frequent in the maxilla in connection with crowding, extreme maxillary overjet, and cross-bite (p less than 0.05). No association was found in the mandible. The presence of certain malocclusion traits in adolescence may probably often call for special professional efforts of oral hygiene education rather than orthodontic therapy.