Gingival recession in mandibular anterior teeth in patients with Class II malocclusion treated with elastics and Twin Force appliance

Comparison of smile attractiveness in cases with gummy smile treated with botulinum toxin and maxillary impaction surgery: A retrospective study

This study aimed to compare the smile's attractiveness in patients submitted to the treatment of gummy smiles with botulinum toxin or maxillary impaction surgery. The retrospective sample comprised 26 patients divided into two groups: Group 1 (BTX): 13 patients (12 females and 1 male) with a mean age of 28.06 years (s.d. = 6.09) and mean gingival exposure during smile of 5.18 mm (s.d. = 1.51) treated with botulinum toxin; Group 2 (SURGICAL): 13 patients (9 females and 4 males) with a mean age of 30.59 years (s.d. = 5.72) and mean gingival exposure during smile of 5.21 mm (s.d. = 1.55) treated with orthognathic maxillary impaction surgery. The group of evaluators comprised 317 participants, divided into 143 orthodontists (85 females and 58 males) with a mean age of 41.40 (s.d. = 9.30); 62 dentists (47 female and 15 male) with a mean age of 35.44 (s.d. = 10.44), and 112 lay people (74 female and 38 male) with a mean age of 46, 91 (s.d. = 10.11) in a questionnaire on Google Forms. Without knowing the therapy used, the evaluators assigned scores to the photographs of the posed smile taken before (T1) and after (T2) treatment. Intergroup comparison of smile attractiveness was performed using the t-independent, one-way ANOVA, and Tukey tests. There was a significant improvement in smile attractiveness with treatment in both groups; however, the improvement was significantly better in the surgical group than in the BTX group. Orthodontists rated smile attractiveness significantly higher than dentists and laypersons for the final phase of the BTX and surgical groups. There was a significant improvement in the smile attractiveness with botulinum toxin application and orthodontic-surgical treatment. However, orthognathic surgery promoted a greater improvement in smile attractiveness than the application of botulinum toxin.

Comparison of Gingival Recession of Mandibular Incisors of Class III Patients Immediately after Compensatory or Surgical Orthodontic Treatment

OBJECTIVE

 This study aimed to compare gingival recession in mandibular anterior teeth in patients with Class III malocclusion, immediately after compensatory or surgical orthodontic treatment.

MATERIALS AND METHODS

 The sample consisted of 40 patients with Class III malocclusion, divided into two groups: Group 1 (compensatory), 20 patients treated with compensatory orthodontics, with a mean initial age of 20.26 years (standard deviation [SD] . = 7.44), mean final age of 23.07 years (SD = 7.32), and mean treatment time of 2.81 years (SD =0.84). Group 2 (surgical), who undergone orthodontic-surgical treatment, with a mean initial age of 23.08 years (SD =5.48), mean final age of 25.43 years (SD =5.12), and mean treatment time of 2.35 years (SD =1.56). Intraoral photographs taken before and after removal of the fixed orthodontic appliance were used to measure the gingival recession, from the cervical of the mandibular incisors from the most cervical point of the gingival margin to the cementoenamel junction. In the initial and final cephalograms, the position of the mandibular incisors was measured. The intergroup comparison was performed using the independent t-test.

RESULTS

 The results showed that there was no statistically significant difference in the gingival recession at the beginning, at the end, and of changes with treatment between the compensatory and surgical groups.

CONCLUSION

 It was concluded that the compensatory and surgical orthodontic treatments for Class III malocclusion showed similar results regarding the gingival recession of the mandibular incisors.

Risk factors for gingival recessions after orthodontic treatment: a systematic review

BACKGROUND/OBJECTIVES

To systematically review the available evidence concerning the risk factors for gingival recessions (GR) after orthodontic treatment (OT).

DATA COLLECTION AND ANALYSIS

Data was obtained and collected by systematically searching 3 data bases: Pubmed, EMBASE, and Web of Science until 20 April 2023. Controlled trials, cohort, case-control or cross-sectional studies describing GR or clinical crown height (CCH) after OT were included. The risk of bias in the selected studies was evaluated with the methodological index for non-randomized studies.

RESULTS

Forty-eight articles were included, investigating the following six risk factors for GR: 1. OT (n = 21), 2. Type of orthodontic intervention (n = 32), 3. Patient's baseline occlusal and skeletal characteristics (n = 14), 4. Mucogingival characteristics (n = 10), 5. Oral hygiene (n = 9), and 6. Others (n = 12). Significantly higher prevalence, severity and extent of GR were found in orthodontic patients by 10/15, 4/10, and 2/2 articles respectively. 10/16 articles reported significantly more GR and increased CCH in patients where orthodontic incisor proclination was performed. The evidence surrounding maxillary expansion and orthodontic retention was too heterogeneous to allow for? definitive conclusions. Pre-treatment angle classification, ANB, overjet, overbite, arch width and mandibular divergence were found not to be associated with GR (9/14), while pre-treatment crossbite, symphysis height and width were (5/7 studies). A thin gingival biotype, presence of previous GR, baseline width of keratinized gingiva and facial gingival margin thickness were correlated with increased risk of GR after OT by nine articles, while pocket depth was not. Oral hygiene, sex, treatment duration, and oral piercings were found not to be linked with GR in orthodontic patients, while GR was reported to increase with age in orthodontic patients by 50 per cent of the articles investigating this factor. The mean risk of bias for comparative and not comparative studies was 14.17/24 and 9.12/16.

LIMITATIONS

The selected studies were quite heterogeneous regarding study settings, variables reported and included very limited sample sizes.

CONCLUSION

Although studies regarding the risk factors for GR are relatively abundant, they are very heterogeneous concerning design, studied factors, methodology and reporting, which often leads to contradictory results. Uniform reporting guidelines are urgently needed for future research.

PROSPERO REGISTRATION

CRD42020181661.

FUNDING

This research received no funding.

Alveolar bone height changes in the anterior tooth region before and after orthodontic treatment for Angle's Class II division 1 malocclusion and related factors

BACKGROUND

The aim of this study was to observe the alveolar bone height changes in the anterior tooth region after orthodontic treatment for Angle's Class II division 1 malocclusion.

METHODS

Ninety-three patients treated from January 2015 to December 2019 were retrospectively analyzed, of whom 48 received tooth extraction and 45 did not.

RESULTS

After orthodontic treatment, the alveolar bone heights in the anterior tooth regions of tooth extraction and non-extraction groups decreased by 67.31% and 66.94%, respectively. Except for the maxillary and mandibular canines in the tooth extraction group as well as the labial side of maxillary anterior teeth and the palatal side of maxillary central incisors of the non-extraction group, the alveolar bone heights of other sites significantly reduced (P<0.05). The reduction in the alveolar bone height of the tooth extraction group significantly exceeded that of the non-extraction group on the palatal side of maxillary incisors and the lingual side of mandibular anterior teeth (P<0.05).

CONCLUSIONS

Alveolar bone height in the anterior tooth region decreases after orthodontic treatment for Angle's Class II division 1 malocclusion, being closely related to tooth position together with movement direction and amplitude.