Highly producible method for determination of occlusal vertical dimension: relationship between measurement of lip contact position with the closed mouth and area of upper prolabium

Slim the face or not: 3D change of facial soft and hard tissues after third molars extraction: a pilot study

BACKGROUND

Whether slim the face or not after removed third molars is the concern of some orthodontic treatment candidates. The aim of this article is to explore the volume changes of facial soft and hard tissues after third molars extraction, as well as develop a reproducible clinical protocol to precisely assess facial soft tissue volume change.

METHODS

A non-randomized, non-blind, self-controlled pilot study was conducted. 24 adults aged 18-30 had ipsilateral third molars extracted. The body weight change was controlled within 2 kg. Structured light scans were taken under a standardized procedure pre-extraction (T0), three (T1), and six (T2) months post-extraction; CBCTs were taken at T0 and T2. The projection method was proposed to measure the soft tissue volume (STV) and the soft tissue volume change (STVC) by the Geomagic software. The hard tissue volume change (HTVC) was measured in the Dragonfly software.

RESULTS

The final sample size is 23, including 5 males (age 26.6 ± 2.5 years) and 18 females (age 27.3 ± 2.5 years). The HTVC was - 2.33 ± 0.46ml on the extraction side. On the extraction side, the STV decreased by 1.396 (95% CI: 0.323-2.470) ml (P < 0.05) at T1, and increased by 1.753 (95% CI: -0.01-3.507) ml (P = 0.05) at T2. T2 and T0 had no difference (P > 0.05). The inter and intra-raters ICC of the projection method was 0.959 and 0.974. There was no correlation between the STVC and HTVC (P > 0.05).

CONCLUSIONS

After ipsilateral wisdom teeth extraction, the volume of hard tissue on the extraction side reduces, and the volume of facial soft tissue does not change evidently. However, further research with large sample size is still needed. The STV measurement has excellent repeatability. It can be extended to other interested areas, including forehead, nose, paranasal, upper lip, lower lip and chin, which is meaningful in the field of orthodontics and orthopedics.

TRIAL REGISTRATION

ChiCTR, ChiCTR1800018305 (11/09/2018), http://www.chictr.org.cn/showproj.aspx?proj=28868 .

Correlation of index finger length to vertical dimensions of occlusion for edentulous patients and their satisfaction: a randomized controlled trial

The prevalence of edentulism is pandemic and people resort to complete dentures for the restoration of missing teeth and esthetics. However, the determination of the correct occlusal vertical dimensions (OVD) constitutes to play an important role in overall patient satisfaction. The objective of this study was to apply anthropometric methods to correlate the length of index finger (2D) to measure the OVD from base of the nose to the base of the chin (Sn-Me) and to assess satisfaction by comparing both the methods. A total of 80 edentulous patients were randomized and controlled for this trial into experimental and control groups. A correlation was found between Sn-Me and finger measurements, dentures' satisfaction was assessed after a 1-week follow-up and marked according to the Visual Analog Scale. Our findings established that finger measurements are greater among males, and in both genders, positive, and statistically significant correlations exist between the facial and finger length measurements. Moreover, 97.0% patients from experimental group were satisfied with the use of complete dentures through the new anthropometric method. Hence measuring the length of index finger can be an adjunct method for the restoration of OVD and is a relatively time-effective and simple method with a satisfactory follow-up.Trial registration: ID: NCT05153213 ( https://clinicaltrials.gov/ct2/show/NCT05153213 ).

Morphologic reproducibility in 6 regions of the 3-dimensional facial models acquired by a standardized procedure: An in vivo study

INTRODUCTION

A standardized procedure was proposed to control involuntary motion and other factors during the capture of structural light scanning that could influence the morphology of 3-dimensional facial models; interoperator reproducibility was evaluated.

METHODS

Twenty subjects volunteered for facial scanning. Three researchers scanned each volunteer 3 times on the same day using the FaceScan structural light scanning system (Isravision, Darmstadt, Germany) and after the proposed procedure. Captures were done at 5-minute intervals. The 3 facial scans acquired by the same researcher were compared by reverse engineering software (Geomagic; 3D Systems, Rock Hill, SC). Six facial regions, including forehead, nose, paranasal, upper lip, lower lip and chin, and cheek, were divided. With the first scan as a reference, the other 2 scans were registered, and surface-to-surface distance maps were acquired to calculate the mean, standard deviation, and root mean squares (RMS) between 2 surfaces. The reproducibility between 3 researchers was then evaluated by a 1-way analysis of variance.

RESULTS

The mean of 6 facial regions was close to 0. The RMS of lip regions were largest (0.48-0.53 mm), the forehead was smallest (0.21 mm), and the others ranged 0.37 mm to 0.42 mm. The standard deviation was slightly smaller than RMS and had the same trend of change. There was no significant difference in RMS among the 3 researchers (P >0.05).

CONCLUSIONS

With the constraint of the standardized procedure, the morphologic reproducibility of facial models in 6 regions was satisfying.

Assessment of knowledge of oral cancer in dentists in the Los Ríos Region, Chile, in 2017

The alteration of the vertical dimension can deteriorate the facial harmony, and it can be measured through objective and subjective methods, although many of which are not reliable. Objective: Relate the anthropometric fingers length with the measurement of the vertical occlusal dimension (VOD). Material and Methods: Cross-sectional, observational study that included 114 students from the School of Dentistry with class I malocclusion and complete dentition. The VOD was evaluated as the measurement between the subnasal points and the mental point; anthropometric measures included the length of the fingers (from the most mesial fold to the most distal edge) and the distance projected between the thumb and the index finger. Results: The average VOD was 64.03±5.15mm. A correlation was found between the VOD and the index finger length (p<0.01, r=0.29), between the VOD and middle finger length (p<0.01, r=0.31) and correlation between the VOD and the length of the little finger (p<0.05, r=0.23). No correlation was found between the VOD and the ring finger lengths (p= 0.051) or thumb (p=0.12). Conclusions: The anthropometric measurements of the index finger, middle finger, little finger and the projection of the thumb on the index finger correlated with the length of the vertical occlusal dimension.