Three-Dimensional Outcome Assessments of Cleft Lip and Palate Patients Undergoing Maxillary Advancement

Three-dimensional planning accuracy and follow-up of Le Fort I osteotomy in cleft lip/palate patients

OBJECTIVES

Our aim was to determine the accuracy of the three-dimensional (3D) virtual planning and stability of LeFort I osteotomy in cleft lip and/or palate patients (CLP) using a validated 3D method.

MATERIALS AND METHODS

Eight patients with a history of cleft lip/palate treated with LeFort I osteotomy for maxillary hypoplasia between January 2016 and April 2020 were included in this retrospective study. Three-dimensional virtual planning was performed using Proplan software then transferred to the operation theater via 3D printed occlusal wafers. The accuracy of the 3D planning and the 1-year stability of the maxilla were evaluated by means of a validated semiautomatic stepwise module in Amira software resulting into 3 linear measurements: anterior/posterior, medial/lateral, superior/inferior and 3 rotational measurements: pitch, roll, yaw.

RESULTS

The largest mean absolute difference (MAD) for accuracy assessment was found in the A/P direction (2.75mm±2.25 mm) and in pitch (3.23°±2.11°). For A/P translation, an error of >2 mm was observed in 5(62.5%), for S/I translation an error of >2 mm was observed in 4(50.0%) of the 8 patients, whereas for pitch 3 patients(37,5%) showed an error >4° At one year follow-up, the largest linear and rotational MAD was found in the A/P direction (1.20mm±0.92 mm) and in pitch (3.31°±2.31°).

CONCLUSIONS

Findings of this study show that 3D virtual computer-assisted orthognathic surgery enables an accurate repositioning of the hypoplastic maxilla in CLP patients. However, A/P translations and pitch rotations remain challenging to achieve during surgery. These movements were also found to be least stable at one year follow-up.

Unilateral Cleft Lip and Palate Has Asymmetry of Bony Orbits: A Retrospective Study

Facial asymmetry is common in unilateral clefts. Since virtual surgical planning (VSP) is becoming more common and automated segmentation is utilized more often, the position and asymmetry of the orbits can affect the design outcome. The aim of this study is to evaluate whether non-syndromic unilateral cleft lip and palate (UCLP) patients requiring orthognathic surgery have asymmetry of the bony orbits. Retrospectively, we analyzed the preoperative cone-beam computed tomography (CBCT) or computed tomography (CT) data of UCLP (n = 15) patients scheduled for a Le Fort 1 (n = 10) or bimaxillary osteotomy (n = 5) with VSP at the Cleft Palate and Craniofacial Center, Helsinki University Hospital. The width, height, and depth of the bony orbit and the distance between the sella turcica and infraorbital canal were measured. A volumetric analysis of the orbits was also performed. The measurements were tested for distribution, and the cleft side and the contralateral side were compared statistically with a two-sided paired t-test. To assess asymmetry in the non-cleft population, we performed the same measurements of skeletal class III patients undergoing orthognathic surgery at Päijät-Häme Central Hospital (n = 16). The volume of bony orbit was statistically significantly smaller (p = 0.014), the distance from the infraorbital canal to sella turcica was shorter (p = 0.019), and the anatomical location of the orbit was more medio-posterior on the cleft side than on the contralateral side. The non-cleft group showed no statistically significant asymmetry in any measurements. According to these preliminary results, UCLP patients undergoing orthognathic surgery show asymmetry of the bony orbit not seen in skeletal class III patients without a cleft. This should be considered in VSP for the correction of maxillary hypoplasia and facial asymmetry in patients with UCLP.

Early experience of wafer-free Le Fort I osteotomy with patient-specific implants in cleft lip and palate patients

PURPOSE

The use of virtual surgical planning and patient-specific saw and drill guides combined with customized osteosynthesis is becoming a gold standard in orthognathic surgery. The aim of this study is to report preliminary results of the use of virtual surgical planning and the wafer-free PSI technique in cleft patients.

MATERIALS AND METHODS

Patient-specific saw and drill guides combined with milled patient-specific 3D titanium alloy implants were used in reposition and fixation in Le Fort I osteotomy of 12 cleft patients. Surgical information was retrieved from hospital records. Pre- and post-operative lateral cephalograms were analyzed.

RESULTS

In 10 of 12 cases, the implants fitted as planned to predesigned drill holes and bone contours with high precision. In one patient, the mobilization of the maxilla was too demanding for virtually planned advancement, and the implants could not be used. In another patient, PSI fitting was impaired due to an insufficient mobilization of maxilla and tension on PSI fixation with screws. After the surgery, the mean advancement of the anterior maxilla (point A) of all patients was 5.8 mm horizontally (range 2.7-10.1) and -3.1 mm vertically (range -9.2 to 3.4). Skeletal relationships of the maxilla and mandible could be corrected successfully in all patients except for the one whose PSI could not be used.

CONCLUSIONS

Virtual surgical planning combined with PSI is a possible useful clinical adjunct for the correction of maxillary hypoplasia in cleft patients. Large maxillary advancements and scarring may be cause problems for desired advancement and for the use of implants.

The Predictability of the Surgical Outcomes of Class III Patients in the Transverse Dimension—A Study of Three-Dimensional Assessment

This study aimed to assess the outcomes of planned maxillary surgical movements in the transverse direction in patients possessing a Class III skeletal pattern. The available consecutive patients’ records were retrospectively reviewed. Only those possessing a Class III skeletal pattern, and for whom the same virtual planning system was used, were enrolled. The waferless technique was used to guide the jawbone repositioning. A representative triangle in the virtual maxilla of each stage was used to validate the planned surgical movements (PSMs) and the outcome discrepancy (OD). The linear and angular measurements were retrieved for the assessments of the correlation between PSM and OD. In total, 44 adult patients who met the inclusion criteria were studied. The average linear OD of the A-point in the transverse direction was 0.66 ± 0.54 mm, and the yaw correction showed 1.02 ± 0.84 degrees in difference. There was no specific correlation between the linear PSMs and ODs; however, the angular ones were positively correlated. With the help of the waferless technique to transfer the virtual planning results, the practitioners could confidently predict the postsurgical maxillary position in the transverse direction in the orthognathic surgery of Class III patients. However, the yaw correction should be carefully planned to avoid postsurgical instabilities.

A Comparative Study of Skeletal and Dental Outcome between Transcutaneous External Maxillary Distraction Osteogenesis and Conventional Rigid External Device in Treating Cleft Lip and Palate Patients

Background: Traditional distraction osteogenesis (DO) with the tooth-borne rigid external device (RED) system was regularly used in treating patients with cleft-related maxillary hypoplasia. However, the bone-borne RED system with miniplates and bone screws has currently become an effective treatment. This retrospective study was to compare bone-borne RED with traditional tooth-borne RED in distraction effectiveness, blood loss, operative time, and long-term stability. Methods: Twenty-two growing patients who underwent RED therapy were divided into two groups: eleven patients utilizing the bone-borne RED system with the transcutaneous wire attached with skeletal anchorage; another eleven patients using the traditional tooth-borne RED system with the intra-oral device attached with dental anchorage. Serial lateral cephalograms were analyzed for comparing treatment outcomes and stability in 1 month, 6 months, and 1.5 years after distraction. Results: In bone-borne RED group, the maxilla was advanced by 19.98 mm with slight clockwise rotation of 0.40° and minimal palatal inclination change of incisor by −3.94°. In traditional tooth-borne RED group, the maxilla showed less advancement by 14.52 mm, with significant counter-clockwise rotation of −11.23° and excessive palatal inclination change of incisor by −10.86°. Although operative time was longer in the bone-borne RED group by 38.4 min, this did not bring about greater blood loss. Conclusions: the bone-borne RED via transcutaneous wire system provides an easy, simple, and comfortable procedure as well as favorable long-term stability in maxillary distraction.

Comparing Surgical Advancement Outcomes of Retruded Maxilla in a Group of Egyptian Cleft Lip and Palate Subjects

BACKGROUND: Cleft lip and palate (CLP) is one of the most common congenital deformities involving intervention in several sub-specialties. AIM: The present study was conducted to investigate the amount of maxillary advancement obtained by three different methods. METHODS: A retrospective comparative study was conducted on 24 CLP patients who were treated with three surgical maxillary advancement techniques: Group A was treated with Le Fort I (LFI) orthognathic surgery with bone grafting and rigid fixation (LFI). Group B was treated with intraoral maxillary bone distraction (MIDO). Group C was treated with orthodontic traction by facemask (orthodontic facemasks [OFM]) plus corticotomy. All pre-operative data were collected, which included intraoral and extraoral clinical photos and dental casts. Pre-operative radiographic assessment was compared with post-operative values using digital panorama, multi-slice computed tomography and lateral cephalometric X-ray measuring Sella-nasion-A point; point A-nasion-point B points, with a follow-up period of 6 months. RESULTS: All approaches showed statistically significant success in maxillary advancement with p < 0.01. LFI has produced the highest advancement obtained with regard to the pre-operative advancement required (8.6 ± 1.4) and post-operative advancement achieved (7.8 ± 0.8). MIDO technique is an alternative method to LFI, but it gives less achieved post-operative maxillary advancement (6.25 ± 0.8) and is indicated for moderate cases. OFM gave the least advancement results; however, it has been the most convenient less-invasive method and was more suitable for unsevere cases. CONCLUSIONS: The three approaches produced satisfactory results in rehabilitating deficient maxilla in cleft patients, although each technique has limitations and indications. Future research is recommended to assess the technique’s long-term stability.

Three-Dimensional Outcome Assessments of Surgical Correction in Cleft and Noncleft Patients with Class III Skeletal Relation: A Case-Control Study

Background

The orthognathic strategies to treat patients with a concave profile but different tissue conditions remain controversial. The aim of this case-control study was to investigate the outcome predictability of orthognathic surgery in cleft lip and palate (CLP) patients and matched controls.

Methods

Fifty consecutive CLP and 45 matched non-CLP patients who received whole-piece Le Fort I and bilateral sagittal split osteotomy to correct class III skeletal relations were enrolled. The outcome discrepancies (ODs) from simulations among all groups were evaluated with consideration of the possible influences from planned surgical movements (PSM). Receiver operating characteristic curves were used to determine threshold values of PSMs that yielded clinically relevant OD.

Results

Unilateral CLP (UCLP) patients had comparable postsurgical OD to non-CLP patients in both jaws, whereas bilateral CLP (BCLP) patients had greater deviations from predicted results. Vertical movement of the A − point > 1.33 mm and yaw correction > 1.65° in the BCLP patients was associated with clinically relevant maxillary OD.

Conclusions

The OGS outcomes of BCLP patients were less predictable than those of the UCLP and noncleft patients. Vertical movements of the A − point > 1.33 mm and yaw correction > 1.65° in BCLP patients increased OD to a clinically relevant extent.