Faculty Bibliography

BACKGROUND:The authors present an institutional experience treating congenital and acquired temporomandibular joint (TMJ) ankylosis, detailing outcomes and potential risk factors of recurrence. METHODS:Retrospective chart review identified patients with TMJ ankylosis (1976-2019). Clinical records, operative reports, and imaging studies were reviewed for demographics, surgical operations, and ankylosis including maximal interincisal opening (MIO) and re-ankylosis. RESULTS:Forty-four TMJs with bony ankylosis were identified in 28 patients (mean age at any initial mandibular surgery: 3.7; range:0-14 years). Follow-up was 13.7 ± 5.9 years. Sixteen (57.1%) patients had bilateral ankylosis; 27(96.4%) had syndromes. Nine patients had congenital ankylosis, 16 had iatrogenic ankylosis (4.5 ± 3.7 years from initial distraction osteogenesis or autologous mandibular reconstruction) referred from outside institutions in 6 instances, and 3 had post-infectious ankylosis. Patients having their first mandibular operation at a younger age had more frequent reoperations for recurrent TMJ ankylosis, although this did not reach statistical significance. Mean improvement in MIO was 21.4 ± 7.3 mm. Ankylosis recurred in 21 (75%) patients. Five patients with congenital TMJ ankylosis required gastrostomy and remained at least partially dependent. Five patients had tracheostomy at the time of TMJ ankylosis surgery: 2 were eventually decannulated and 3 required repeat tracheostomy after ankylosis recurrence and remained tracheostomy-dependent. CONCLUSION/CONCLUSIONS:The clinical course of TMJ ankylosis in children affected by craniofacial differences is complex and typically involves a high rate of recurrence and multiple reoperations despite initial improvement in postoperative MIO. Younger age at initial mandibular surgery and number of operations require further investigation as potential predictors of recurrent TMJ ankylosis as well as tracheostomy and gastrostomy dependence.

Pierre Robin sequence is the constellation of micrognathia, glossoptosis, and tongue-based airway obstruction. When airway obstruction is severe, feeding, growth, and respiratory demise are at risk. Neonatal mandibular distraction osteogenesis is a technique which improves tongue-based airway obstruction and avoids tracheostomy in patients with severe expressions of Pierre Robin sequence. Its efficacy in relieving airway obstruction is well documented, and it has become the surgical intervention of choice at many craniofacial centers. However, this is an uncommon procedure which can be performed within the first weeks of life, offering little space for a learning curve. The success of neonatal distraction and avoidance of complications is highly dependent on proper surgical technique. This report provides a brief overview of the disease, details the technique of the senior surgeon with captioned videos, describes the protocol used at our institution and reports long-term outcomes with a case description.

Children with cleft and craniofacial conditions commonly present with concurrent airway anomalies, which often manifest as sleep disordered breathing. Craniofacial surgeons and members of the multidisciplinary team involved in the care of these patients should appreciate and understand the scope of airway pathology as well as the proper means of airway assessment. This review article details the prevalence and assessment of sleep disordered breathing in patients with craniofacial anomalies, with emphasis on indications, limitations, and interpretation of polysomnography.

Background/Purpose: Le Fort I advancement surgery is challenging in patients with clefts because of the palatal scar tissues. In this study, we investigated the outcome of Le Fort I advancement surgery (mild, moderate, and severe groups) and 1-year skeletal stability in patients with cleft lip and palate. Methods/Description: A retrospective chart review was performed to identify patients with nonsyndromic unilateral or bilateral cleft lip and palate who underwent maxillary Le Fort I advancement at skeletal maturity from 2013 to 2019. To satisfy the inclusion criteria, all patients had to have diagnostic quality cone beam computed tomography (CBCT) prior to surgery (T0), immediately postoperative (T1), and at 1-year follow-up (T2). A total of 59 patients (unilateral n = 34, bilateral n = 25) who underwent Le Fort I advancement was identified. Nineteen of these 59 patients were excluded due to insufficient radiographic records; thus, 40 patients with complete records were included in the study. The sample was comprised of 9 females and 31 males, with an average age of 19.1 +/- 3.21 years at the time of the surgery. Lateral cephalograms were extracted, traced, and superimposed using Dolphin Imaging software (V 11.95). Horizontal surgical movement (T0-T1) and postoperative relapse (T1-T2) at skeletal and dental level were quantified as linear changes at point A and upper incisor edge (U1-tip), respectively. Patients were divided into 3 groups according to the severity of surgical movement: mild (<5 mm, n = 9), moderate (5-10 mm, n = 20), and severe (>10 mm, n = 11). The statistical analysis was performed using 2-way repeated-measures ANOVA to test the difference of surgical movements and postoperative relapse between groups.
Result(s): The mean advancement (T0-T1) of all patients at point A was 8.1+/-2.8 mm and at U1-tip was 7.7+/-2.6 mm. In the mild, moderate, and severe groups, the mean advancement at point A were 4.6 +/- 1.3 mm, 7.7+/-1.1 mm, and 11.6+/-1.2 mm, and at U1-tip were 5.7+/-2.9 mm, 7.4 +/- 1.3 mm, and 10 +/- 2.6 mm, respectively. There were significant skeletal and dental advancements in all the 3 groups following Le Fort I surgery (P < .0001). At 1-year follow-up, the mean relapse (T1-T2) at point A was 1.2 +/- 1.1 mm and at U1-tip was 0.07 +/- 1.9 mm. When analyzed within the mild, moderate, and severe groups, the mean relapse at point A were 0.8 +/- 0.7 mm, 1.2 +/- 0.9 mm, and 1.9+/-1.5 mm and at U1-tip were -0.4+/-1.6 mm, 0.4+/-2.1 mm, and -0.2 +/- 1.5 mm, respectively. There was no significant difference in the relapse amount between the mild, moderate, and severe groups at skeletal and dental components (P > .05).
Conclusion(s): Le Fort I advancement surgery successfully corrected maxillary hypoplasia in patients with cleft lip and palate in all the 3 groups. This study also demonstrated that larger advancement in the severe group can result in equivalent skeletal stability when compared to the mild and moderate advancement. Though mild skeletal relapse was observed in all the 3 groups, none of the patients had to be reoperated

Background/Purpose: We present the first long-term outcomes analysis of the nasoalveolar molding (NAM) treatment protocol on patients with a cleft followed from birth to facial maturity. Methods/Description: Single-institution retrospective review of all patients with a cleft who underwent NAM between the years 1990 and 2000. All study patients completed cleft care treatment at the same institution and were followed by the same team members. Our institution's treatment protocol offers NAM to patients with a significant cleft nasal deformity and/or widely displaced alveolar segments. All patients underwent primary cleft lip and nasal repair prior to the age of 6 months. Gingivoperiosteoplasty (GPP) is performed, when possible, at the time of lip repair. Cleft palate repair is performed by 1 year of age. Collected data include surgical and orthodontic outcomes of cleft care such as cleft lip and palate repair, GPP, alveolar bone grafting (ABG), speech surgery for velopharyngeal insufficiency (VPI), palatal fistula repairs, orthognathic surgery, and revision surgery to the nose and/or lip.
Result(s): A total of 135 patients met the inclusion criteria. Mean length of follow-up was 18.8 years. Eighty-nine patients presented with a unilateral cleft (UNI) and 46 with a bilateral cleft (BI); 84% (113/135) of patients underwent GPP (UNI: 78% [69/89]; BI: 96% [44/46]), 43% (58/135) of patients underwent ABG (UNI: 40% [36/89]; BI: 48% [22/46]), 18% (24/135) of patients underwent speech surgery for VPI (UNI: 14% [12/89]; BI: 26% [12/46]), 3% (4/135) of patients underwent palatal fistula repair (UNI: 0% [0/89]; BI: 9% [4/46]), 31% (42/135) underwent orthognathic surgery (UNI: 22% [20/89]; BI: 48% [22/46]), and 11% (15/135) underwent revision surgery to lip, nose, or both prior to facial maturity (UNI: 9% [8/89]; BI: 15% [7/46]]. Of the patients who underwent GPP, 61% (69/113) did not require ABG (UNI: 65% [45/69]; BI: 55% [24/44]) and 42% (48/113) required neither ABG nor orthognathic surgery (UNI: 51% [35/69]; BI: 30% [13/44]).
Conclusion(s): Clinical outcomes of the NAM treatment protocol from birth to facial maturity demonstrate a low rate of revision surgery to the lip and nose, as well as a low fistula and VPI rate. The frequency of orthognathic surgery reported in this study is consistent with published data. In addition, 42% of patients who underwent NAM with GPP required neither ABG nor orthognathic surgery

Background/Purpose: The evolution of primary unilateral cleft lip repair represents a series of incremental modifications pioneered by a distinct group of master surgeons. It is through understanding the purpose of each evolutionary step, the limits and compromises of these steps, and the subsequent modifications which followed, can a greater understanding of the art of cleft lip repair be realized. This course will trace the conceptual development of unilateral cleft lip repair over the past 70 years using a novel, real-time computer-based cleft lip simulator. A first order accurate biophysics implementation within the simulator will be used to demonstrate the cleft lip repair techniques described to reveal the strengths and weaknesses of each stage of unilateral lip repair development. The course will begin with the Tennison Randall lower triangular lip repair, as it is still in common use today. This will be followed by Skoog, Wynn, and Mustarde adding an upper triangle to the lip repair. The various stages in the progression of the Millard repair will then be carefully traced along with the biophysics which are likely responsible for why Millard altered his original design. The modifications of the Millard design by other surgeons, and the reasons for them, will then be carefully traced. The modifications covered will be those of Noordhoff, Mohler, Cutting, Fisher, and others. The interaction between lip repair technique and primary correction of the cleft-lip nasal deformity will be discussed in detail. Simulator-based demonstrations will be augmented with patient examples from the senior author's clinical practice which illustrate the conceptual difficulties encountered at various stages in the historical development of primary unilateral cleft lip and nose repair. Methods/Description: The principal method used in this course will be real-time computer-based surgical simulation. A unilateral cleft lipnose model involving skin, mucosa, muscle, bone, cartilage, and teeth was derived from an MR scan of an adolescent with an unrepaired unilateral cleft. Alterations in the model are illustrated with first-order accurate biophysics using a new software base called projective dynamics. Surgical tools provided are scalpel, suture, hook, and undermine of both skin/mucosa and bone/cartilage. Surgical "'history" files are used to step through a succession of cleft lip repairs in the surgical eclectic. The presentation will be augmented with photographs from the senior author's long career further illustrating why successive alterations in technique were made

Background/Purpose: b-Tricalcium phosphate (b-TCP), the most common synthetic bone replacement product, is frequently used in craniofacial reconstruction. Although solid b-TCP can be absorbed over time, the slow degradation rate (1%-3%/year) predisposes this product to exposure, infection, and fracture, limiting its use in the growing face where implants are required to grow and remodel with the patient. Our tissue engineering laboratory has successfully leveraged 3D printers to manufacture 3D-printed bioactive ceramic (3DPBC) scaffolds composed of b-TCP in an architecture which optimizes the needs of rigidity with efficient vascular ingrowth, osteogenesis, and degradation kinetics. The latter qualities are further optimized when the osteogenic agent dipyridamole (DIPY) is used. This long-term animal study reports on the new degradation kinetics profile achievable through this novel manufacturing and tissue engineering protocol. Methods/Description: Twenty-two 1-month-old (immature) New Zealand white rabbits underwent creation of unilateral 10 mm calvarial defects with ipsilateral 3.5 +/- 3.5 mm alveolar defects. Each defect was repaired with b-TCP 3DPBC scaffolds coated with 1000 mM DIPY. Rabbits were killed at 8 weeks (n = 6), 6 months (n = 8), and 18 months (n = 8). Bone regeneration and scaffold degradation were calculated using micro-CT images and analyzed in Amira software. Cranial and maxillary suture patency and bone growth were qualitatively analyzed using histologic analysis.
Result(s): Results are reported as a percentage of volumetric space occupied by either scaffold or bone. When comparing time points 8 weeks, 6 months, and 18 months, scaffolds showed significant decreased defect occupancy in calvaria (23.6% +/- 3.6%, 15.2% +/- 1.7%, 5.1% +/- 3.4%; P < .001) and in alveoli (21.5% +/- 3.9%, 6.7% +/- 2.7%, 0.1% +/- 0.2%; P < .001), with annual degradation rates 55.9% and 94.2%, respectively. Between 8 weeks and 18 months, significantly more bone regenerated in calvarial defects (25.8% +/- 6.3% vs 55.7% +/- 10.3%, P < .001) and no difference was found in alveolar defects (28.4% +/- 6.8% vs 32.4% +/- 8.0%, P = .33). Histology showed vascularized, organized bone without suture fusion.
Conclusion(s): The degradation kinetics of b-TCP can be altered through 3D printing and addition of an osteogenic agent. Our study demonstrates an acceleration of b-TCP degradation from 1% to 3% a year to 55% to 95% a year. Absorbed b-TCP is replaced by vascularized bone and there is no damage noted to the growing suture. This additive manufacturing and tissue engineering protocol has implication to future reconstruction of the craniofacial skeleton

Background/Purpose: Our study quantifies changes in skeletal, soft tissue profile, and globe position in patients with syndromic craniosynostosis after Le Fort I + III (LF I + III) surgery. Methods/Description: Patients with syndromic craniosynostosis who underwent LF I + III at the time of facial maturity were followed for at least 1 year. Each lateral cephalometric radiograph was traced using Dolphin Imaging software and superimposed at the sella. Changes in positions of the different landmarks at T0 (preoperatively), T1 (immediate postoperatively), and T2 (1 year postoperatively) were measured by the software. Sixty-seven soft tissue and skeletal landmarks were digitized and measured. LF III skeletal changes were measured by changes in lateral orbit and orbitale. LF I skeletal changes were measured at the A point and U1. Corresponding soft tissue profile and globe position were studied. All data were measured along the x-axis.
Result(s): Twelve patients included in our study have the following syndromes: Crouzon (n = 6), Pfeiffer (n = 2), Apert (n = 1), Antley-Bixler (n = 1), cleidocranial dysplasia (n = 1) and frontonaso dysplasia (n = 1). Nine patients had previous history of LF III distraction. Standard descriptive statistics was used. Data were analyzed using paired T test. Lateral orbit advanced 5.49 mm (T0-T1) on average, with a P value of 1.3-5, and 5.94 mm (T0-T2) on average; 0.45 mm (T1-T2) change with a P value of .96 suggests the lateral orbit is stable. Similar advancement at orbitale is observed at 5.68 mm (T0-T1) and 6.42 mm (T0-T2). The globe moved anteriorly by 1.98 mm (T0-T1) with a P value of .025 and anteriorly by 0.944mm(T0-T2). The change between T2 and T1 is 1.04 mm (P value: .26), which suggests the globe moved backward after postsurgical swelling subsided. The ratios of movement (globe to lateral orbit) between T0-T1 and T0-T2 are 31% and 16%, respectively. The decrease in ratio can be attributed to the reduction in soft tissue swelling at T2. Restoring position of the globe relative to the lateral orbit decreases the risk of exposure keratitis, keratoconjunctivitis sicca, and corneal ulceration. Anterior nasal spine and point A were advanced by 9.38 and 10.08 mm, respectively, between T0 and T1, and 9.01 mm and 8.51 mm, respectively, between T1 and T2. At the occlusal level, U1 advanced 10 mm and L1 moved back 1.45 mm between T0 and T1. Menton moved back 1.25 mm (T0-T1) but advanced by 2.48 mm (T0-T2). This change in direction is due to splint use at T1 as it rotates mandible clockwise.
Conclusion(s): In our cohort, LFI + III surgery improved both midface deficiency and proptosis in those with syndromic craniosynostosis.Combined Le Fort I + III surgery allows surgeons to perform differential corrections of the midface at the orbital and the dentition level. This is ideal for proptosis correction and establishing optimal jaw relationship

Background/Purpose: Temporomandibular joint (TMJ) ankylosis is an uncommon but debilitating condition which can affect feeding, speech, dental health, facial growth, and quality of life. We present an institutional experience treating congenital and acquired TMJ ankylosis, detailing outcomes and potential risk factors of recurrence. Methods/Description: Patients with ankylosis of the TMJ were identified through retrospective chart review (1976-2019). Clinical records, operative reports, and imaging studies were reviewed for demographics, surgical operations, and ankylosis including mean interincisal opening (MIO) and reankylosis.
Result(s): Forty-four TMJs with bony ankylosis were identified in 28 patients, 27(96.4%) of whom had syndromes. Mean age at any initial mandibular surgery was 3.7+/-3.6 (range: 0-14 years). Follow-up was 13.7 +/- 5.9 years. Sixteen (57.1%) patients had bilateral ankylosis. Nine cases of ankylosis were congenital, 16 were iatrogenic (4.5 +/- 3.7 years from initial distraction osteogenesis or autologous mandibular reconstruction) referred from outside institutions in 6 cases, and 3 were postinfectious. Patients having their first mandibular operation at a younger age had more frequent reoperations for recurrent TMJ ankylosis, although this did not reach statistical significance. Improvement in MIO was 21.4 +/- 7.3 mm. Ankylosis recurred in 21(75%) cases, 11 of which were iatrogenic, requiring an average of 2 reoperations (range: 1-8). Five patients with congenital TMJ ankylosis required gastrostomy and remained at least partially dependent. Five patients had tracheostomy at the time of TMJ ankylosis surgery: 2 were eventually decannulated and 3 required repeat tracheostomy after ankylosis recurrence and remained tracheostomy-dependent.
Conclusion(s): Craniofacial anomalies, younger age at mandibular surgery, and number of operations portend to increased risk of TMJ ankylosis as well as tracheostomy and gastrostomy dependence. Despite initial improvement in postoperative MIO, pediatric TMJ ankylosis is associated with high recurrence and multiple reoperations

BACKGROUND:Three-dimensionally-printed bioceramic scaffolds composed of β-tricalcium phosphate delivering the osteogenic agent dipyridamole can heal critically sized calvarial defects in skeletally mature translational models. However, this construct has yet to be applied to growing craniofacial models. In this study, the authors implanted three-dimensionally-printed bioceramic/dipyridamole scaffolds in a growing calvaria animal model and evaluated bone growth as a function of geometric scaffold design and dipyridamole concentration. Potential adverse effects on the growing suture were also evaluated. METHODS:Bilateral calvarial defects (10 mm) were created in 5-week-old (approximately 1.1 kg) New Zealand White rabbits (n = 16 analyzed). Three-dimensionally-printed bioceramic scaffolds were constructed in quadrant form composed of varying pore dimensions (220, 330, and 500 μm). Each scaffold was coated with collagen and soaked in varying concentrations of dipyridamole (100, 1000, and 10,000 μM). Controls consisted of empty defects. Animals were killed 8 weeks postoperatively. Calvariae were analyzed using micro-computed tomography, three-dimensional reconstruction, and nondecalcified histologic sectioning. RESULTS:Scaffold-induced bone growth was statistically greater than bone growth in empty defects (p = 0.02). Large scaffold pores, 500 μm, coated in 1000 μM dipyridamole yielded the most bone growth and lowest degree of scaffold presence within the defect. Histology showed vascularized woven and lamellar bone along with initial formation of vascular canals within the scaffold lattice. Micro-computed tomographic and histologic analysis revealed patent calvarial sutures without evidence of ectopic bone formation across all dipyridamole concentrations. CONCLUSION/CONCLUSIONS:The authors present an effective pediatric bone tissue-engineering scaffold design and dipyridamole concentration that is effective in augmentation of calvarial bone generation while preserving cranial suture patency.