The Applicability of the Moyers, Tanaka-Johnston, and Gross-Hasund Analysis and a New Formula for the Vietnamese Population.

Aim: Our aim is to determine the applicability of other analyses and develop a new formula appropriate for the Vietnamese population. Materials and Methods: A cross-sectional descriptive analysis was conducted on a total of 120 dental arch samples (18-25 years old, 60 males, and 60 females) with <5 mm of tooth crowding, complete teeth on the dental arch, no missing teeth, and no fillings on the mesial or distal sides. Each study sample will be imprinted and measured using conventional as well as digital methods. Result: There was a significant discrepancy between the overall mesiodistal width from canine to second premolar in the maxilla and mandibular measured with electronic calipers on the cast model and the values calculated by the Moyer, Tanaka - Johnston, Gross - Hasund formulae in the mandibular, and measured by digital scanning and results calculated by the Gross-Hasund formula for maxilla and mandibular and the Moyers, Tanaka-Johnston formula for mandibular. The values obtained were compared with those calculated using the Moyers, Tanaka-Johnston, and Gross-Hasund formulae for the mandibular. Additionally, measurements were taken by digital scanning, and the results were calculated using the Gross-Hasund formula for both the maxilla and mandibular, and the Moyers and Tanaka-Johnston formulae for the mandibular. When used to estimate space analysis in the Vietnamese population, the estimation formula for each gender had greater accuracy and reliability than other widely used methods. Conclusions: As the central incisor and first molar are the first permanent teeth to erupt, the mesiodistal width may be readily measured. This new formula may be used to predict the width in the early stages of the mixed dentition.

Cone Beam CT Assessment of Mandibular Foramen and Mental Foramen Positions as Essential Anatomical Landmarks: A Retrospective Study in Vietnam.

INTRODUCTION: The mandibular foramen (MnF) and the mental foramen (MF) are essential anatomical landmarks that should be considered before any surgical procedures in the mandible. This study aimed to investigate the characteristics of the MnF and MF in relation to adjacent anatomical structures, as well as age and gender differences, using cone beam computed tomography (CBCT) projections. METHODS: The study was conducted from August 2023 to January 2024 at the Can Tho University of Medicine and Pharmacy Hospital, Vietnam. In this retrospective study, 50 CBCT images of Vietnamese patients were randomly taken for various clinical purposes. Furthermore, relevant data, such as gender and age groups, were selected to evaluate the correlations, along with specific inclusion criteria. Patients within the age range of 18-69 with a symmetrical mandible were included. RESULTS: The distance of the MnF-MN was 29.6±5.0 mm (right) and 30.1±4.6 mm (left) in males and 25.0±4.2 mm (right) and 26.3±5.0 mm (left) in females. The distance of the MnF-posterior border of the ramus (P) was 16.2±3.6 mm (right) and 15.0±2.3 mm (left) in males. For females, it was 17.1±2.9 mm (right) and 13.8±1.7 mm (left). The distance of the MF-body mandible (MB) was 15.4±2.4 mm (right) and 15.6±2.0 mm (left) in males and 14.0±2.1 mm (right) and 14.3±1.6 mm (left) in females. The distance of the MF-mandibular midline (MM) was 27.0±2.6 mm (right) and 27.0±2.9 mm (left) in males and 25.3±2.0 mm (right) and 25.1±2.2 mm (left) in females. These distances showed statistically significant differences depending on gender (P<0.05). CONCLUSION: It can be said that CBCT provides comprehensive information about the MnF and the MF for dentists in research and clinical practice.

Platelet-rich plasma's (PRP) impacts on accelerated canine movement.

OBJECTIVE: To investigate the impact of platelet-rich plasma (PRP) on canine movement acceleration. METHODS: Randomized clinical trial split-mouth study with a double-blind design and controlled group on 31 orthodontic patients, which had been indicated bilateral maxillary first premolar extraction. Each patient recorded clinical features, analyzed lateral cephalometric film, and evaluated the acceleration on dental models at every specific interval. RESULT: The cumulative distance to the distal canines was larger for the PRP injection group than for the control group at three time points (4 weeks, 8 weeks, and 12 weeks), all of which were statistically significant. The PRP injection group's canine distal width increased from the first 4 weeks (ΔT1) to the highest in the middle 4 weeks (ΔT2 = 1.78 ± 0.11 mm/month), and then it gradually decreased in the last 4 weeks (ΔT3). The speed of the PRP-injected canine was faster than the control group by 1.51 times. CONCLUSION: PRP can accelerate the speed of canine movement in orthodontics and can be applied for severe cases, for example, impacted tooth retraction, molar protraction or retraction, and other cases.