Pyramidal and posterior osseous release for maxillary superior/posterior mobilization using an ultrasonic bone-cutting device after Le Fort I osteotomy

Horseshoe osteotomy maintains the nasal cavity and function after superior repositioning

The aim of this prospective cohort study was to compare changes in nasal cavity and function between Le Fort I with and without horseshoe osteotomy after superior repositioning of the maxilla. The patients were divided into 2 groups, a Le Fort I alone (LF alone) group and a combination Le Fort I and horseshoe osteotomy (HS) group. The nasal cavity volume was measured using 3-dimensional computed tomographic images, and nasal resistance was assessed by anterior active mask rhinomanometry. The HS group consisted of 17 patients, and the LF alone group consisted of 15 patients. The magnitude of change in nasal cavity volume was significantly smaller in the HS group than in the LF alone group (p < 0.001), even though the mean amount of superior maxillary movement was considerably larger in the HS group than in the LF alone group (p < 0.001). Mean nasal resistance was significantly smaller postoperatively than preoperatively in the HS group (p < 0.05). Furthermore, the change in nasal resistance was smaller in the HS group than in the LF alone group (p < 0.001). Within the limitations of this study, it seems that horseshoe osteotomy is useful for maintaining the nasal cavity and function after superior repositioning of the maxilla.

Progress in Excision Methods of Bone Materials

Bone resection is a common technique in modern surgery, which can be divided into contact (such as mechanical osteotomy and ultrasonic osteotomy) and non-contact (such as laser osteotomy). Irrespective of the excision method, it causes processing damage to natural bone material, thus affecting bone healing. To reduce the machining damage in bone resection, different machining variables (cutting fluid temperature, feed rate, rotational speed, and ultrasonic frequency) were considered to explore the selection of various cutting conditions. This paper reviews the excision of natural bone materials including mechanical osteotomy, laser osteotomy, and ultrasonic osteotomy, especially traditional drilling and ultrasonic cutting, which represent the traditional and prospective methods of bone excision technology, respectively. Finally, the differences between methods are emphasized and the future trends in osteotomy technology and condition control during osteotomy are analyzed.

A Simple Method to Retract the Descending Palatine Neurovascular Bundle During Osseous Removal of Posterior Interferences in Le Fort I Osteotomy

ABSTRACT

For accurate repositioning of the maxilla in Le Fort I osteotomy, bone removal around the descending palatine neurovascular bundle and maxillary tuberosity is frequently required. Such task can be challenging due to the high vascularity of the region, which is the most common site of hemorrhage during removal of bony interferences. Although a rare occurrence, ligation of the descending palatine artery in cases of intraoperative vascular damage can be related to the development of aseptic necrosis. This article reports a simple technique for retraction and protection of the descending palatine neurovascular bundle during bony removal related to a posterior maxillary impaction, which can be easily reproduced in orthognathic selected cases.

Surgical procedures for correcting vertical maxillary excess: A review

INTRODUCTION

Vertical maxillary excess, a common orthodontic problem that leads to long faces and open bites, can be repositioned with a Le Fort I osteotomy. However, the Le Fort I osteotomy poses the risk of a variety of complications including descending palatine artery (DPA) injury. Although several Le Fort I osteotomy modifications were reported to avoid complications associated with this osteotomy, only a few of such studies were conducted in Japan, and details remain scarce.

PATIENTS AND METHODS

We performed a literature review regarding modifications of Le Fort I osteotomies, including Le Fort I with a horseshoe osteotomy, modified horseshoe osteotomy, unilateral horseshoe osteotomy, pyramidal osteotomy, and U-shaped osteotomy. We identified eight relevant studies conducted in Japan; one study did not provide the number of patients examined. The 77 patients (seven studies) with vertical maxillary excess who underwent orthognathic surgery were ≥17 years old.

DISCUSSION

There were no severe complications after the modified Le Fort I osteotomies. The postoperative maxillary changes obtained by the conventional horseshoe, modified horseshoe, unilateral type of horseshoe, pyramidal, and U-shaped osteotomies were nearly repositioned to the planned position and remained stable for ≥12 months post-surgery.

CONCLUSION

Our review indicates that preserving the DPA can lower the incidence of intra- and post-operative complications. Each modification of the Le Fort I osteotomy (i.e., conventional horseshoe, modified horseshoe, unilateral horseshoe, pyramidal, and U-shaped osteotomy) has its respective advantages and indications.