The Effects of Orthodontic Therapy on Periodontal Health

Severe periodontitis and orthodontics: evaluation of long-term results

Clinical manifestations of severe periodontitis are very often associated with tooth migration. The aim of this retrospective study is to evaluate dental bone support before orthodontic-periodontal treatment, at immediate postoperative, and long-term postoperative and to compare these results with those obtained from periodontal treatment alone. Fifteen patients (11 women and four men), all with severe periodontitis, mean age 42.8 years (22-61), were followed for an average of 16 years (11-32). Comparison was made between periodontal-orthodontic treatment (Group 1) and periodontal treatment alone (Group 2). Alveolar bone height was measured at T0 (before treatment), T1 (immediate postoperative) and T2 (long-term postoperative). Assessment was performed by means of digitized radiography using Image J Software from the National Institute of Health. The average postoperative observation period between T0 (before treatment) and T2 (long-term results) was 16 years (11 to 32). Results showed an overall bone apposition in groups (1 and 2) immediately after treatment (T1), then at long-term (T2). No statistical difference was observed between both groups (1 and 2).

IN CONCLUSION

an overall bone gain was observed in both treatment groups (periodontal-orthodontic and periodontal alone). The orthodontic treatment combined with periodontal treatment never compromised the benefits of periodontal treatment alone. On the opposite, it appeared to be quite beneficial.

Evaluation of dehiscences using cone beam computed tomography

Objective:

To validate the use of three-dimensional (3-D) surface rendering (SR) images to quantify the height of alveolar dehiscences.

Materials and Methods:

Twenty-four dehiscences were created on 9 incisors, 9 canines, and 6 premolars on 4 cadaver skulls. i-CAT cone beam computed tomography scans (CBCTs) were taken of each skull at .2 mm voxel size. Each dehiscence was quantified by 21 orthodontic residents using 3-D SR. The principal investigator (PI) also quantified each dehiscence using the 2-D multiplanar (MP) image and the 3-D SR image.

Results:

Results of this study showed an average method error of the residents as a group to be 0.57 mm with an intraclass correlation (ICC) of 0.77%. Residents' method error ranged from 0.45 mm to 1.32 mm, and the ICC ranged from 0.201% to 0.857%. Systematic error was low at −0.01 mm for the direct measurement compared with the residents' average 3-D SR at 1365 density value (DV) measurement. The 3-D SR at 1365 DV images were compared with the MP and 3-D SR images at 1200 DV, and no significant differences in measurements and low systematic error were noted. The method error of the PI was 0.45 mm, 0.45 mm, and 0.41 mm for 3-D SR at 1365 DV, 3-D SR at 1200 DV, and 2-D MP, respectively.

Conclusions:

3-D SR and 2D MRP can be used to measure dehiscences of the periodontium with similar levels of accuracy.

An update on periodontic-orthodontic interrelationships

Talking about periodontic-orthodontic interrelationships is related primarily to the 1960s, where a generalized increase in salivary bacterial counts, especially Lactobacillus, had been shown after orthodontic band placement. The purpose of this article is to provide the dental practitioner with basic understanding of the interrelationship between periodontics and orthodontics by means of representing classical studies, and, to give an update on this topic by demonstrating the most recent opinions concerning periodontic-orthodontic interrelationships. Specific areas reviewed are the ability of orthodontic treatment to afford some degree of protection against periodontal breakdown, short-term and long-term effects of orthodontic treatment on the periodontium, and some mucogingival considerations. Topics considering orthodontic treatment in periodontally compromised patients were not included in this review. While past studies have shown that orthodontic treatment can positively affect the periodontal health, recent reviews indicate an absence of reliable evidence for the positive effects of orthodontic therapy on patients’ periodontal status. Periodontic-orthodontic interrelationships are still controversial issues. However, a standard language between the periodontist and the orthodontist must always be established to eliminate the existing communications barrier, and to improve the outcomes of the whole treatment.

Prevalence and severity of vestibular recession in mandibular incisors after orthodontic treatment

Objective:

To assess the prevalence and severity of vestibular gingival recession of mandibular incisors after orthodontic treatment and to evaluate possible contributing factors.

Materials and Methods:

From the record pool of patients who completed orthodontic treatment from 1999–2006 at the Department of Orthodontics, University of Oslo, Norway, 588 patients fulfilled the inclusion criteria. Intraoral color slides were used for the evaluation of gingival recessions (based on Miller classification), presence of visible plaque, and gingival inflammation. Cephalometric radiographs were used to assess the sagittal intermaxillary relation, mandibular and intermaxillary angles, and the position of the lower incisors. A control group was drawn from the same pool of 588 patients. All statistical analyses were performed using SPSS.

Results:

The prevalence of gingival recessions after orthodontic treatment was 10.3%. Most (8.6%) were classified as Miller Class I, and 1.7% were classified as Miller Class II. Gingival recession was predominantly found on central incisors. Reduction of the sagittal intermaxillary angle and retroclination of the lower incisors was correlated with the development of a more severe gingival recession.

Conclusions:

The present study indicates that vestibular gingival recession of mandibular incisors after orthodontic treatment is of minor prevalence and severity. The presence of gingival recession or retroclination of the incisors with mesial basal relations increases the risk of more severe gingival recession.

Orthodontic treatment of periodontal defects. Part II: A systematic review on human and animal studies

Several studies have been published focusing on the possibility to treat patients affected by periodontal defects by means of orthodontic treatment. The aim of this systematic review is to evaluate the efficacy of the orthodontic treatment applied to the therapy of infraosseous defects, gingival recessions, and furcation lesions. An electronic and a manual search were performed based on a PICO assessment worksheet. Both human and animal studies were selected for this review. The electronic search (from January 1966 to December 2009) and the hand search (from January 1988 to December 2009) were conducted by 3 independent reviewers. A total of 197 articles were found and only 29 were considered eligible for this review. In particular, 22 studies dealing with infrabony defects, 1 gingival recession, and 6 furcation defect treatments. Due to the weak evidence and the controversial and unclear results, it appears important to encourage the researchers to produce Randomized Controlled clinical Trials aimed to investigate the efficacy of the orthodontic treatment for the correction of periodontal defects.

Periodontal health and relative quantity of subgingival Porphyromonas gingivalis during orthodontic treatment

OBJECTIVE

To examine periodontal changes and the relative quantity of subgingival Porphyromonas gingivalis during orthodontic treatment.

MATERIALS AND METHODS

The study subjects were recruited consecutively among malocclusion patients seeking orthodontic treatment. Group A comprised 28 subjects (17.6 ± 5.68 years of age) at the beginning of orthodontic treatment, and group B comprised 20 subjects (17.8 ± 4.49 years of age) at the end of orthodontic treatment. Plaque index (Pl.I), gingival index (GI), and probing pocket depth (PPD) were measured before and after appliance placement in group A and before and after appliance removal in group B. Real-time quantitative polymerase chain reaction was used to quantify P. gingivalis in subgingival plaque at each time point.

RESULTS

There was a significant increase in Pl.I and GI during the first 3 months of appliance placement but a significant decrease in Pl.I, GI, and PPD during the first 6 months after appliance removal. The carriage and relative quantity of subgingival P. gingivalis were high at the end of orthodontic treatment, and they decreased significantly after appliance removal. The amount of subgingival P. gingivalis after appliance removal (for a period of 6 months) was higher than the amount measured before appliance placement.

CONCLUSIONS

Fixed orthodontic treatment is conducive to dental plaque accumulation and gingival inflammation. In our study, after removal of orthodontic appliances, periodontal health improved, and the carriage and amount of subgingival P. gingivalis decreased. Nevertheless, the amount of subgingival P. gingivalis remained high for 6 months after appliance removal, and this finding might imply a potential risk to periodontal health in certain patients.

[Plaque control, a key element of successful orthodontics]

It is mainly because of periodontal tissues and, more particularly, the periodontal ligament that the orthodontist is able to move teeth. According the ratio cost/benefit/security, the orthodontist needs to prevent and/or to avoid the deleterious effects of its treatments on periodontal tissues. Gingival inflammation with a high hyperplasia compound, periodontal attachment loss, bone loss and root resorption may result, in absolute value, in a reduction of periodontal support. The key to prevent these problems is plaque control, phase too often neglected. The challenge before any orthodontic treatment, both in children or in adults, is to change the behavior of the patient concerning the mouth and the dental plaque. The aim of this paper is to explore the evidence based literature (systematic revues, meta-analysis), to provide thought elements and concrete proposals to definitely resolve this critical phase of orthodontic treatment that is the motivation, phase that can also be achieved by "dental auxiliaries".

Impact of social and economic characteristics on orthodontic treatment among children and teenagers in France

OBJECTIVES

This study aimed to estimate the prevalence of orthodontic treatment in France among children and teenagers aged 8-18 years, by sex and by age, and to investigate the specific role of social and economic characteristics on use of orthodontic treatment.

METHODS

We analyzed data from the cross-sectional national health survey conducted in France in 2002-2003, which included a sample of 5988 children aged 8-18 years. All data were collected by interview including the question on orthodontic treatment. Other data used in our study were family social status and income, maternal educational attainment and place of birth, whether the child was covered by a supplementary health insurance and whether the residence was urban or rural. We also calculated the density of orthodontists in the district. Multivariate logistic regression analyses were used to study the relationships between these social and economic factors and orthodontic treatment.

RESULTS

The prevalence of orthodontic treatment was 14% of all children aged 8-18, 15% for girls, and 13% for boys, and 23% in the 12 to 15-year age group. Children were less likely to have orthodontic treatment when parents were service or sales workers compared with children whose parents were managers or professionals (aOR = 0.50; 95%CI: [0.34;0.76]), when family income was in the lowest, compared with highest quartile (aOR = 0,62; 95% CI: [0.45;0.85]), when children had no supplementary insurance compared with children covered by private insurance (aOR = 0.53; 95% CI: [0.34; 0.81]), or when they lived in rural compared with urban areas (aOR = 0.70; 95% CI: [0.54; 0.91]).

CONCLUSION

There are social inequalities in orthodontic treatment in France, associated mainly with social status, annual income, supplementary insurance, and the residence area.

[Orthodontic tooth displacement: histology, biology and iatrogenic effects]

Iatrogenic effects of orthodontic forces, in particular root resorption, are described in the literature. However, our knowledge on the risk of osseous defects induced by orthodontic treatment is still scarce. After an overview of histological and biological principles of orthodontically-induced tooth movement, this study focuses on the recent data concerning the occurrence and the treatment of bone resorption associated with orthodontic treatment.

Alveolar Bone Loss around Incisors in Surgical Skeletal Class III Patients

Objective: To test the hypothesis that there is no difference in the vertical alveolar bone levels and alveolar bone thickness around the maxillary and mandibular central incisors in surgically treated skeletal Class III malocclusion patients.

Materials and Methods: The study sample comprised 20 Korean patients with skeletal Class III malocclusion with anterior crossbite and openbite (9 male, 11 female, mean ages 24.1). Three-dimensional cone beam computed tomography images were taken at least 1 month before the orthognathic surgery, and sagittal slices chosen at the labio-lingually widest point of the maxillary and mandibular right central incisor were evaluated. Measurement of the amount of vertical alveolar bone levels and alveolar bone thickness of the labial and lingual plate at the root apex was made using the SimPlant Pro 12.0 program.

Results: The mandibular incisors showed reduced vertical alveolar bone levels than the maxillary incisors, especially on the lingual side. The alveolar bone thickness was significantly greater on the lingual side in the maxillary incisors, whereas the mandibular incisors exhibited an opposite result (P < .05). The percentage of vertical bone loss to root length showed a statistically significant difference between the upper labial and lower labial alveolar bone and also between the upper lingual and lower lingual alveolar bone, showing more bone loss in the lower incisors (P < .001).

Conclusions: The hypothesis is rejected. For the skeletal Class III patients undergoing orthognathic surgery, special care should be taken to prevent or not aggravate preexisting alveolar bone loss in the anterior teeth, especially in the mandible.

Periodontal pathogen levels in adolescents before, during, and after fixed orthodontic appliance therapy

INTRODUCTION

This purpose of this study was to document and investigate changes in periodontal pathogen levels before, during, and after orthodontic treatment in adolescents.

METHODS

DNA gene probe analysis was used to quantify the levels of 8 periodontal pathogens before, during, and after treatment with fixed orthodontic appliances in 190 concurrently treated adolescent orthodontic patients. The 8 pathogens examined were Actinobacillus actinomycetemcomitans (AA), Porphyromonas gingivalis (PG), Prevotella intermedia (PI), Tannerella forsythia (TF), Eikenella corrodens (EC), Fusobacterium nucleatum (FN), Treponema denticola (TD), and Campylobacter rectus (CR). Chi-square tests were used to determine whether the percentages of subjects with high counts significantly changed over time. Logistic regression analyses were also performed to derive the relative risk of higher counts of pathogenic bacteria with fixed appliances at the various time intervals studied.

RESULTS

For 6 (PI, TF, EC, FN, TD, CR) of the 8 pathogens, the percentages of subjects with high pathogen counts increased significantly after 6 months of fixed appliance treatment, but these returned to pretreatment levels by 12 months of orthodontic treatment. No pathogen level was significantly higher after 12 months of orthodontic treatment, and orthodontic treatment was found to be significantly protective for half of the pathogens (EC, FN, TD, CR) posttreatment.

CONCLUSIONS

Orthodontic treatment with fixed appliances does not increase the risk of high levels of these periodontal pathogens.