A novel osteogenic distraction device for the transversal correction of temporozygomatic hypoplasia

Morphometric and morphological evaluation of temporozygomatic suture anatomy in dry adult human skulls

This study aims to evaluate the position, morphometric, and morphological features of the temporozygomatic suture (TZS) located on the zygomatic arch (ZA) in dry adult human skulls. Thirty-two crania were evaluated. Measurements for the TZS were carried out using the ImageJ software. Morphometric measurements were carried out bilaterally in 23 crania and unilaterally in 9 crania (right: 4, left: 5). A total of 55 TZSs were analyzed. Localization of the TZS was determined according to the reference landmarks on the ZA. Morphologic features of the TZS evaluated in terms of "joint shape type" and "suture margin pattern". Descriptive statistics of the morphometric and morphologic variables were calculated. A statistically significant difference between the right and left sides was observed for the localization of the TZS (p < 0.05). TZS is located more anteriorly on the left side than the right side. Based on the "joint shape type", four types of TZS were observed: Type 1 (angular) (34.55%), Type 2 (curvy) (34.55%), Type 3 (oblique) (14.55%), Type 4 (horizontal) (16.36%). Based on the "suture margin pattern", five types of TZS were observed: Type A (linear) (12.73%), Type B (denticulate) (34.55%), Type C (serrated) (23.64%), Type D (mixt) (21.82%), Type E (fused) (7.27%). No significant association between the type and lateralization was found for both morphologic classifications. To the best of our knowledge, this is the first published report regarding the localization and morphologic classification of the TZS in adult human crania. Considering the TZS with its morphometric and morphological features may contribute to clinical or forensic medical evaluations.

Precise positioning of an intraoral distractor using augmented reality in patients with hemifacial microsomia

BACKGROUND

Through three-dimensional real time imaging, augmented reality (AR) can provide an overlay of the anatomical structure, or visual cues for specific landmarks. In this study, an AR Toolkit was used for distraction osteogenesis with hemifacial microsomia to define the mandibular osteotomy line and assist with intraoral distractor placement.

METHODS

20 patients with hemifacial microsomia were studied and were randomly assigned to experimental and control groups. Pre-operative computed tomography was used in both groups, whereas AR was used in the experimental group. Afterwards, pre- and post-operative computed tomographic scans of both groups were superimposed, and several measurements were made and analysed.

RESULTS

Both the conventional method and AR technique achieved proper positioning of the osteotomy planes, although the AR was more accurate. The difference in average vertical distance from the coronoid and condyle process to the pre- and post-operative cutting planes was significant (p < 0.01) between the two groups, whereas no significant difference (p > 0.05) was observed in the average angle between the two planes. The difference in deviations between the intersection points of the overlaid mandible across two cutting planes was also significant (p < 0.01).

CONCLUSION

This study reports on an efficient approach for guiding intraoperative distraction osteogenesis. Augmented reality tools such as the AR Toolkit may be helpful for precise positioning of intraoral distractors in patients with hemifacial microsomia in craniofacial surgery.