Evaluating Morphology of the Pterygomaxillary Junction and Its Association With the Orbit in Different Facial Skeletal Relationships

Evaluation of nasolacrimal canal morphology in different facial skeletal relationships

BACKGROUND

Abnormal morphological variations of nasolacrimal canal (NLC) and its lack of understanding contributes to acquired injuries during craniomaxillofacial surgical procedures which leads untoward postoperative complications like nasolacrimal obstruction (NLO) and epiphora.

PURPOSE

The purpose of this study was to determine dimensional and volumetric morphological variations of nasolacrimal canal in various facial skeletal relationships which aid in performing a precise and safe surgery.

MATERIALS AND METHODS

This retrospective cohort study involved dimensional and volumetric analysis of nasolacrimal canal procured from computed tomography scans of 47 individuals grouped as ClassI, Class II and Class III, and unilateral cleft lip and palate (UCLP) groups. The outcome variables included length of NLC, volume of NLC, distance between the inferior orifice of the NLC to nasal floor, distance between inferior orifice of NLC to canine apex and distance between inferior orifice of NLC to central incisor apex. The objectives were to analyse morphological variation of NLC in different facial skeletal relationships and to evaluate the variation with change in facial sides and its relationship with surrounding structures.

RESULTS

Volume of the NLC was found significant in Class I and UCLP population (p < 0.05) with the greatest volume in the UCLP group. The mean linear and volumetric measurements between the right and left sides were found insignificant among all groups. Inferior orifice of NLC from canine apex were farthest in Class III and nearest in the UCLP group (p < 0.05). There was no significant association between outcome variables and skeletal base configuration.

CONCLUSION

NLC demonstrates dimensional and anthropometric variations between different skeletal relationships and this study is inevitable in understanding the probability of NLC injury during maxillofacial surgeries.

Anatomical Variations of the Greater Palatine Foramen in Different Facial Skeletal Relationships and its Implications on LeFort 1 Osteotomy (Trimble's Modification)

Purpose

To determine the positional variations of the greater palatine foramen in different facial skeletal relationships and discuss its surgical implications on the Trimble's modification of Lefort I osteotomy.

Materials and Methods

This retrospective study examined 50 computed tomography scans of patients a total of 100 sides. The sample was divided into four groups: Class 1, Class 2, Class 3 malocclusion and Unilateral cleft lip and palate). The outcome variables included the distance between anterior, middle and posterior points of the GPF to the distal of second molar and variables to assess relative position of the GPF to the posterior maxilla. Outcome measures were to demonstrate intra- and intergroup variability.

Results

Fifty patients (100 sides) were divided into four groups. This included 23 males and 27 females with a mean age of 24.1 years. Significant intergroup variability was observed between all the parameters that demonstrate the relative position of the GPF to (i) the maxillary second molar and (ii) the posterior maxilla. The analysis revealed that the GPF was positioned significantly anterior in Class 2 patients when compared with Class 3 patients.

Conclusion

The GPF exhibits significant positional variability in different facial skeletal relationships which should be borne in mind while designing and performing the Trimble's modification of the Lefort 1 osteotomy.

Endoscopically Assisted LeFort I Osteotomy for Minimally Invasive Orthognathic Surgery: A Technical Note

Minimally invasive surgery in orthognathic surgery has gained popularity in recent years. This is mainly due to the benefit to the patient of achieving a better postoperative period and a faster recovery. However, one of the main difficulties is the lack of direct vision, which is a concern for the surgeon. For this reason, this technical note aims to propose endoscopically assisted LeFort I osteotomy for MI orthognathic surgery.