Periodontal and root changes after orthodontic treatment in middle-aged adults are similar to those in young adults

Differences in the 3-dimensional aging changes of the lips among female adults with skeletal Class I, II, and III malocclusion

INTRODUCTION

The objective of this study was to evaluate and compare the 3-dimensional (3D) aging changes of the lips among adult skeletal Class I, II, and III malocclusion.

METHODS

Female adult orthodontic patients aged 20-50 years with pretreatment cone-beam computed tomography scans were retrospectively classified according to age (20s [20-29 years], 30s [30-39 years], and 40s [40-49 years]) and then subclassified by malocclusion into skeletal Class I, II, and III relationship (9 groups; n = 30 per group). Positional differences in midsagittal and parasagittal soft-tissue landmarks and 3D morphologic aging changes of the lips were evaluated using cone-beam computed tomography scans.

RESULTS

Labiale superius and cheilion for patients in their 40s indicated a significant downward and backward position compared with those in their 20s, regardless of skeletal classifications (P <0.05). Accordingly, the upper lip height decreased, and the mouth width increased significantly (P <0.05). For Class III malocclusion, the upper lip vermilion angle was greater for patients in their 40s than those in their 20s (P <0.05), whereas the lower lip vermilion angle was only lower for patients with Class II malocclusion (P <0.05).

CONCLUSIONS

Middle-aged adult females (40-49 years) had a lower upper lip height and greater mouth width than those in their 20s, regardless of skeletal malocclusion. However, prominent morphologic aging changes of the lips were noted on the upper lip for skeletal Class III malocclusion and the lower lip for skeletal Class II malocclusion, implying that the underlying skeletal features (or malocclusion) may influence 3D aging changes of the lips.

Asymmetric Extraction Treatment in a Middle-Aged Patient with Dental Crowding and Protrusion using Clear Aligners

Frequently, orthodontic treatment involves symmetrically extracting premolars to correct severe crowding or protrusion. Nevertheless, in some cases, a more reasonable alternative may be to remove teeth with poor prognoses to improve protrusion and relieve crowding. A middle-aged woman sought treatment for dental protrusion and crowding. Her mandibular right first molar had been treated with root canal therapy due to pulpitis, but she still felt uncomfortable. In addition, her maxillary left second premolar had become carious. Extractions of the maxillary right first premolar and left second premolar, as well as mandibular right first molar and left first premolar were chosen to resolve the occlusion problems. The patient opted for clear aligners on the demands of esthetics as well as comfort. Following orthodontic treatment, the patient attained properly aligned teeth, a pleasing smile, and a facial profile that exhibited greater harmony. This case report demonstrates that, under proper planning, clear aligners are capable of handling challenging cases, including those involving middle-aged individuals and molar extractions.

Incidence and clinical risk factors associated with the development of labial protuberances after orthodontic treatment

INTRODUCTION

Distinct, irregular, and hard, nodular labial protuberances (LPs) that were due to differential alveolar bone modeling can be noted on the labial gingival surface of the incisors after orthodontic treatment. Clinically, LPs cause patient discomfort and esthetic issues, but information on this phenomenon is limited. This study aimed to evaluate the incidence of LPs and demonstrate the etiology and clinical risk factors associated with this phenomenon.

METHODS

Differential alveolar bone modeling was defined as present (+) when ≥1 distinct LPs (diameter >1 mm) developed after orthodontic treatment by comparing pretreatment and posttreatment intraoral photographs and casts of an orthodontic patient cohort treated with fixed appliances (n = 872). The incidence rate, affected sites, and their association with age, sex, and orthodontic treatment modalities were evaluated.

RESULTS

The incidence rate of differential alveolar bone modeling among orthodontic patients was 3.2% (28 out of 872). The maxillary lateral incisor region was the most frequently affected site. Males (vs females) (odds ratio, 2.56 [95% confidence interval, 1.155-5.604]), adults (aged ≥ 20 years) (vs teens) (12.84 [3.003-54.866]), and those who had orthodontic extraction (vs nonextraction) (11.60 [3.434-39.156]) demonstrated significantly higher odds of developing LPs after orthodontic treatment (P <0.05).

CONCLUSIONS

The incidence rate of the development of notable LPs after orthodontic treatment was 3.2%. Adult males and those who undergo orthodontic extraction have a higher risk of developing LPs. Clinicians should be aware that distinct LPs may develop when large amounts of incisal retraction are planned in adults.

Morphologic changes of the incisive canal and its proximity to maxillary incisor roots after anterior tooth movement

INTRODUCTION

The objectives were to evaluate the morphologic changes of the incisive canal (IC) and the influence of IC proximity to apical root resorption of maxillary central incisors after anterior tooth movement.

METHODS

Pretreatment and posttreatment cone-beam computed tomography images of adults (aged 18-47 years) were retrospectively evaluated. Subjects were divided into control group with minimal incisor movement (n = 32; maxillary incisor tip movement <2 mm) and maximum retraction group (n = 35; maxillary incisor tip movement >4 mm). The shape, direction, morphologic changes of the IC, the proximity of the central incisor root to IC, and the amount of apical root resorption associated with the proximity after orthodontic treatment were compared.

RESULTS

Changes in the shape of the IC were not observed in both control and retraction groups. However, 11.4% (4 of 35 subjects) in the retraction group indicated changes in the direction of the IC from slanted-straight to slanted-curved type after the direction of anterior retraction. The thickness of the cortical bone surrounding the IC and the distance between the incisor root and IC significantly decreased after orthodontic treatment in both groups (P <0.05). However, these changes were significantly greater in the retraction group than in control (P <0.0001). Contact or invasion of the incisor root to the IC was more prominent in the retraction group (42.8%-54.3%) than the control (10.9%-12.5%) (P <0.0001). The amount of root resorption indicated a tendency to increase in the order of separation, approximation, contact, and invasion in relation to IC.

CONCLUSIONS

Although remodeling of IC was evident in some patients, contact or invasion of the maxillary central incisor roots to IC was fairly high after maximum anterior retraction.

The effect of orthodontic treatment on the periodontium and soft tissue esthetics in adult patients

Objective

Most patients seek orthodontic treatment to achieve an esthetic outcome. Orthodontic treatment has possible negative sequelae. The aim of this study is to assess these possible effects on the periodontium and tissue esthetics.

Methods

One hundred fifty‐six patients who have completed orthodontic treatment at Jordan University of Science and Technology clinics were recruited. They were divided into extraction and nonextraction subgroups. Another 155 patients never undergoing orthodontic treatment were assessed. The height of papilla, width of keratinized gingiva, gingival recession, degree of tooth display, smile line, crestal bone level, and proximal caries were assessed. Chi‐ square test was used for categorical/discrete variables while independent t‐test was used for continuous variables. The level of significance was set at (p ≤ 0.05).

Results

The mean age was 22 years with no significant difference between the groups. There was a significant difference between “ortho” and “nonortho” groups in tooth display and keratinized gingiva (p = 0.006 and <0.001, respectively). The overall crestal bone level, smile line, recession, and papilla fill did not show any significant differences (p = 0.200, 0.067, 0.120, and 0.066, respectively). The crestal bone level in the upper and lower anterior segments was significantly lower in the “ortho” treated group compared to the “nonortho” treated group (p = 0.002 and 0.005, respectively). A significant difference between “extraction” and “nonextraction” groups was in the width of keratinized gingiva (p = 0.003) and the number of teeth displayed (p < 0.001). Despite reaching statistical significance these differences are not necessarily of clinical significance.

Conclusion

Orthodontic treatment clearly affects the periodontal tissues; however, the detrimental effects appear to be minimal. Patients with history of orthodontic treatment might have lower crestal bone levels at certain sites and this should not be confused with periodontal disease.

Incisive canal remodelling following maximum anterior retraction reduces apical root resorption

INTRODUCTION

The objectives were to visualize the incisive canal (IC) remodelling following maximum incisor retraction and to evaluate its impact on canal-invasion-associated apical root resorption.

METHODS

Pre- and post-treatment CBCT images of 34 adult orthodontic patients (age 18-47 years) with a large amount of maxillary incisor retraction (>4 mm) using temporary anchorage devices (TADs) were retrospectively evaluated. Maxillary regional superimpositions and 3D models of the IC along with central incisors were used to measure the changes in IC dimension, IC invasion by the roots and IC remodelling. In addition, the association of the amount of apical root resorption with the root-IC relationship and IC remodelling were evaluated.

RESULTS

IC invasion by the incisor roots following maximum retraction was seen in 53% (18 out of 34) of the cases. IC with larger volume and area showed more invasions compared with those with smaller volume and area (P < .01). The amount of root resorption was significantly higher with IC invasion than without invasion (2.39 mm vs 0.82 mm, P < .0001). IC remodelling following maximum retraction was seen in 24% of the subjects. IC remodelling group demonstrated less apical root resorption than the non-remodelling group (0.98 mm vs 3.27 mm, P < .0001).

CONCLUSION

IC with larger volume and surface area before treatment were more likely to show canal invasion by the incisor roots after maximum retraction. IC invasion resulted in apical root resorption. However, approximately one-fourth of cases showed remodelling of the IC, which reduced the amount of root resorption.