Posterior Defects Research Articles

New Approach for Endoscopic Endonasal Transsphenoidal Pituitary Surgery: Modified Nasoseptal Rescue Flap.

Endoscopic endonasal approach has become popularly preferred for pituitary surgery in recent years. In this study we described a new technique which is developed by the first author and which is modified from The Rivera-Serrano "salvage" flap approach. With this new technique the septum morbidity was completely prevented and a wider and more comfortable vision was provided for the operation. This study consists 7 patients who underwent endoscopic endonasal transsphenoidal pituitary surgery (EETPS) with the described technique (modified salvage flap technique) between 2017 and 2019 and 13 patients underwent EETPS using salvage flap technique. The follow-up period was at least 6 months (24-6 months) for septal integrity. Intraoperative septum integrity was observed in all 7 patients who were treated with modified rescue flap technique. In 9 of 13 patients who had salvage flap technique, intraoperative septum posterior defects were observed. In postoperative follow-up (min postop 3 months), endoscopic examination showed no septal perforation in 6 patients who were treated with modified rescue flap technique, and 1 patient had 2 × 2 mm perforation posteriorly. In postoperative endoscopic follow-up of 13 patients who underwent salvage flap technique (min postop 3 months), 4 patients had complete septal integrity, while 9 patients had different sizes of posterior septal perforation. According to other described approach techniques, our modification using a pedicle and septum protective-transposition technique provides improved access to the downstream side of the sphenoid sinus and clivus, allowing the pedicle to slide down and take a more horizontal position. The improved maneuverability of the pedicle created in the case of cerebrospinal fluid leakage as a complication also allows it to be used as a bilateral wing to cover the exposed bone. We think that this technique is the best method to be used for EETPS with modified saline flap technique.

Lateral segmental mandibulectomy reconstruction with bridging reconstruction plate and anterolateral thigh free flap: a case series of 30 consecutive patients

Lateral posterior segmental mandibular defects present a reconstructive challenge and an osseous flap would be the gold standard to reconstruct such a defect. However, combining a mandibular reconstruction plate (MRP) with a soft-tissue free flap (to restore mucosal integrity and provide durable coverage of the plate itself) offers an alternative option for posterior segmental mandibular defects in patients who are not suitable for osseous reconstruction, or do not choose it. We retrospectively reviewed 30 consecutive patients (19 male and 11 female) who underwent reconstruction of a segmental mandibulectomy defect using a bridging MRP and anterolateral thigh (ALT) free flap. The mean (range) age was 67 (31-87) years. The American Society of Anesthesiologists’ (ASA) status of the study population comprised Grade 1 (n = 10), Grade 2 (n = 18), and Grade 3 (n = 2). The majority of patients had oral cavity squamous cell carcinoma (n = 26) involving the mandible, two had osteoradionecrosis, and two mucoepidermoid carcinoma. Four patients had complications specific to the reconstruction, and flap loss occurred in one (96.7% success rate). Metalwork infection occurred in three, including one plate extrusion and one plate fracture. The median length of stay was 10 days, and mean (range) duration of follow up 23.3 (1-96) months. This technique is an alternative reconstructive option for the non-tooth-bearing mandible. Reconstructing a posterolateral segmental mandibulectomy defect with a bridging MRP and ALT free flap offers a robust reconstructive alternative with a favourable complication profile.

Propeller Flaps in the Posterior Trunk.

The reconstruction of complex posterior trunk defects remains challenging. But now with an increased knowledge of angiosomes and the practice of perforator flaps, the posterior trunk offers a new plethora of options for reconstruction. Propeller flaps based on such perforator(s) offer an elegant solution for managing defects while achieving primary donor-site closure without significant morbidity. We will discuss the relevant anatomy and design principles for propeller flaps based on a review of the literature and our experience. Steps beginning with preoperative planning, perforator selection, and intraoperative surgical technique will be discussed, together with pearls on both avoiding and managing complications.

Location of the Glenoid Defect in Shoulders with Recurrent Posterior Glenohumeral Instability

Objectives:Posterior glenoid bone deficiency is an increasingly recognized entity in the setting of recurrent posterior shoulder instability; however, little is known about the subject. Due to the paucity of literature on posterior bone loss, historical comparisons to anterior bone loss may not be fully accurate. The purpose of this study was to systematically describe the morphology of posterior bone defects in the setting of recurrent posterior shoulder instability based on several quantitative parameters, including the mean location, orientation, and extent of bone loss on a clock face model, as well as the angle of the defect relative to the long axis of the glenoid.Methods:3-dimensional (3D) reconstructed computed tomography (CT) scans of serially collected patients with a history of recurrent posterior shoulder instability were evaluated by three separate reviewers. The posterior glenoid bone defect was characterized using the following measures: (a) the mean lesion location and orientation based on a clock face model with 6:00 o’clock denoted as inferior and 9:00 o’clock as directly posterior for all patients; (b) the total extent of the posterior bone defect based on the clock face; and (c) the average angle of the bone loss relative to the long axis of the glenoid.Results:A total of 70 male patients and 1 female patient with mean age of 29.3 years (range = 24.4 to 35.1 years) were included in the analysis. The mean clock face location of the posterior glenoid defect originated at 6:44 (range = 4:16 to 8:12) and extended to a mean of 9:28 (range = 7:02 to 10:38). The mean extent of the posterior glenoid defect was 2:43 (range = 1:08 to 4:50), which corresponds to a mean total bone loss arc of 81.5° (range = 34.2° to 144.9°), nearly one quadrant of the glenoid. Posterior bone loss occurred in a posteroinferior direction at a mean angle of 30.7° (range = 8.0° to 80.0°) relative to the long axis of the glenoid.Conclusion:This study describes the location and orientation of posterior glenoid bone loss one can expect when treating this challenging patient population. Posterior bone defects in the setting of posterior shoulder instability most commonly occur in the posterior-inferior quadrant of the glenoid and extend on average from 6:44 to 9:28 (81.5° total degrees of arc) on a clock face model. Posterior bone loss occurs at a mean of 30° off the long axis of the glenoid in a posteroinferior direction, which is historically different from anterior bone loss, which occurs parallel to the long axis of the glenoid. This study serves to highlight the location and orientation of bone loss that one can expect in a patient with recurrent posterior shoulder instability, although additional work is needed to assess why this develops.Figure 1.Figure 2.Figure 3.Figure 4.

Minimally Invasive Pedicle Screw Fixation Combined with Percutaneous Kyphoplasty Under O-Arm Navigation for the Treatment of Metastatic Spinal Tumors with Posterior Wall Destruction.

ObjectiveTo evaluate the safety and efficacy of O‐arm‐guided minimally invasive pedicle screw fixation combined with percutaneous kyphoplasty for metastatic spinal tumors with posterior wall destruction.MethodsPatients who underwent minimally invasive pedicle screw fixation combined with percutaneous kyphoplasty for pathological vertebral fractures with posterior wall defects from January 2015 to December 2017 were followed up for 1 year. Visual analogue scale (VAS), SF‐36 scores, middle vertebral height, posterior vertebral height, and the accuracy of pedicle screws were assessed preoperatively, postoperatively, and 1 year after surgery. The operation time, time from operation to discharge, blood loss, volume of bone cement, and leakage of bone cement were recorded.ResultsTwenty‐three patients (13 females and 10 males) who met our criteria were followed up for 1 year. The operation time of these patients was 162.61 ± 33.47 min, the amount of bleeding was 230.87 ± 93.76 mL, the time from operation to discharge was 4.35 ± 2.42 days, and the volume of bone cement was 3.67 ± 0.63 mL. The VAS score decreased from 7.04 ± 1.07 to 2.65 ± 0.93 before surgery (P = 0.000) and remained at 2.57 ± 0.79 1 year after surgery. Compared with the preoperative SF‐36 scores for physical pain, physiological function, energy, and social function, the postoperative scores were significantly improved (P = 0.000). The height of the middle vertebral body increased from 14.47 ± 2.96 mm before surgery to 20.18 ± 2.94 mm (P = 0.000), and remained at 20.44 to 3.01 mm 1 year after surgery. The height of the posterior vertebral body increased from 16.56 ± 3.07 mm before operation to 22.79 ± 4.00 mm (P = 0.000), and 22.45 ± 3.88 mm 1 year after surgery. The 23 patients had a total of 92 pedicle screws; 85 screws were Grade A and 7 screws were Grade B. There was no leakage of bone cement after surgery.ConclusionIn the short term, O‐arm‐guided minimally invasive pedicle screw fixation combined with kyphoplasty is safe and effective in the treatment of metastatic spinal tumors with posterior wall destruction.

Investigation of correlation between bony pelvis dimensions and pelvic organ prolapse in different compartments

ObjectiveTo investigate the association between bony pelvis dimensions and anterior, apical, and posterior compartment pelvic organ prolapse (POP) and explore the mechanism of different types of POP from an anatomical point of view. Study designA total of 253 patients with POP were selected as the experimental group (138 patients with anterior compartment defect, 86 with apical compartment defect, and 29 with posterior compartment defect); 253 patients with uterine myoma constituted the control group. Their demographics were recorded, and anteroposterior diameters of the pelvic inlet, intertuberous diameter, and interspinous diameter were measured. One-way analysis of variance, least significant difference t-test, and Student’s t-test were used to evaluate the pelvic measurements among the four groups. ResultsThe anteroposterior diameter of the pelvic inlet in the apical compartment POP group was smaller than that in the other groups (P < 0.05). Interspinous diameters in the anterior and apical groups were larger than those in the posterior POP and control groups (P < 0.05). Intertuberous diameter in the control group was smaller than that in the anterior and apical POP groups and larger than that in the posterior POP group (P < 0.05). ConclusionWomen with apical compartment POP are more likely to have a smaller anteroposterior diameter. Larger interspinous and intertuberous diameters were associated with anterior and apical POP, and smaller intertuberous diameter was associated with posterior POP.

Comparative study of collagen and elastin content of abdominal wall fascia in inguinal hernia and non-hernia patients in an African population.

Altered composition of collagen and elastin in abdominal fascia has been linked with the pathogenesis of hernias. This has not been studied amongst Africans who have hernia presentations which vary significantly from Caucasian cohorts. The aim of this study was to determine, and compare, the collagen and elastin contents of the transversalis fascia and rectus sheath of inguinal hernia patients with non-hernia controls. Twenty-five patients with solitary, primary, uncomplicated inguinal hernia and twenty-five non-hernia controls were evaluated. Biopsies of the transversalis fascia and anterior rectus sheath were stained with Masson Trichrome and Verhöeff van-Gieson to isolate collagen and elastin respectively, which were quantified using the ImageJ/Fiji® image analysis software. Inguinal hernia patients were aged 19-85years with a mean age of 45.2years, mean body mass index (BMI) of 23.3kg/m2 and mean duration of hernia of 42.5months. Lateral hernias with no hernia defect or posterior wall defect [PL0] were the predominant clinical type. There were significantly lower collagen and higher elastin content in the transversalis fascia and rectus sheath of inguinal hernia patients [P < 0.001]. Regression analysis identified smoking and long duration of hernias as independent predictors of low collagen levels in this study CONCLUSION: Inguinal hernia patients in the study population demonstrated depleted collagen in the connective tissue of the inguinal canal. This might justify the routine use of prosthetic mesh for the reinforcement of the posterior wall during hernia repair.

Preoperative assessment of posterior capsular integrity using a posterior segment OCT with a +20 D lens: The 'conical sign' to suggest capsular deficiency in posterior polar cataracts.

To study the morphology of posterior polar cataracts and posterior lens capsules using modified posterior segment optical coherence tomography (m-OCT). Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India. A prospective observational case series. Patients with clinically diagnosed posterior polar cataracts were included. The routine posterior segment OCT was modified by placing an aspheric +20.00 diopter lens along its aperture, enabling it to visualize the anterior segment structures. Cases of posterior polar cataract were assessed preoperatively using this method to study the morphology of posterior lens cortex and the posterior capsule. All m-OCT observations were performed by 2 observers, and findings were recorded. A total of 26 eyes of 17 patients were included. The mean age of patients was 53 years. The morphology of the cataract appeared as hyperreflective opacity just anterior to the posterior capsule, subsequently involving it, and with variable hyporeflective spaces. An intact posterior capsule showed a regularly convex contour, whereas a loss in the tracing of posterior capsule at the paracentral region and disturbance in contour with a localized protrusion of lens matter (the conical sign) depicted a possible posterior capsule dehiscence. Four (15.38%) of 26 eyes showed the conical sign, and this posterior capsule defect was confirmed intraoperatively in all cases. In posterior polar cataracts, the conical sign could be a valuable clue to predict preexisting posterior capsule dehiscence and could be identified on a m-OCT.

Incidental findings of posterior arch defects of the atlas in orthodontic patients: A case series

Congenital defects of the posterior arch of atlas are uncommon anomalies that may go unnoticed. Radiographs and cone-beam computed tomography scans made for orthodontic purposes often show the atlas; therefore, these rare defects might first be noted as incidental findings on orthodontic records. A series of 7 cases of posterior arch defects of atlas (C1) that were detected during routine radiographic examination are presented here. The distribution of the defects was as follows: type A, 2; type B, 1; type C, none; type D, 1; and type E, 3. As the potential complications associated with these defects may be quite concerning, a thorough analysis of the radiographs for these defects is imperative.

Use of Lateral Calcaneal Flap for the Reconstruction of Posterior Heel Defect

Soft tissue defect of the lateral malleolus and achilles tendon is very challenging for reconstruction due to the bony prominence and limited local tissue availability. The purpose of this study to describe our early experience of 30 patients treated with this flap for reconstruction of posterior heel defects with or without exposure of tendo-achilles. The study was conducted at department of plastic surgery, National Institute of Traumatology and Orthopedic Rehabilitation between 2015 to 2018. Twenty five patients (20 male and 5 females) with soft tissue defects over the posterior heel underwent reconstruction using a lateral calcaneal flap. The etiology is trauma in twelve patients, chronic ulcer in four and surgical wound dehiscence for repair of Tendo-Achilles in nine patients. Patients age range from 15 to 60 years (mean 35yrs) and follow up period ranged from 6 months to 2 years(mean 1 yr). All flaps had good perfusion and survived completely. In 3 cases there was partial loss of skin graft managed conservatively. The lateral calcaneal flap can be used safely to provide sensory skin coverage of posterior heel in single stage&#x0D; J Bangladesh Coll Phys Surg 2020; 38(3): 116-120

A finite element analysis of tibial tritanium cones without stems in varying bone defects

BackgroundIn the UK around 10% of hip and knee arthroplasties are revision operations. At revision total knee arthroplasty (rTKA), bone loss management is critical to achieving a stable bone-implant construct. Though tritanium cones have been used to manage bone defects in rTKA, their biomechanical performance with varying defects remains unknown. MethodsUncontained tibial bone defects at four anatomic locations, with varying depths and widths (Type T2A and T2B) were investigated computationally in a composite tibia which was subjected to four loading scenarios. The ability of the tritanium cone to replace the tibial bone defect was examined using the outcome measures of bone strain distribution and interface micromotions. ResultsIt was found that anterior and lateral defects do not significantly alter the strain distribution compared with intact bone. For medial defects, strain distribution is sensitive to defect width; while strain distributions for posterior defects are associated with defect width and depth. In general, micromotions at the bone-implant interface are small and are primarily influenced by defect depth. ConclusionsOur models show that the cone is an acceptable choice for bone defect management in rTKA. Since all observed micromotions were small, successful osteointegration would be expected in all types of uncontained defects considered in this study. Tritanium cones safely accommodate uncontained tibial defects up to 10 mm deep and extending up to 9 mm from the centre of the cone. Medial and posteriorly based defects managed with symmetric cones display the greatest bone strains and asymmetric cones may be useful in this context.

Anterior Capsule Augmentation and Posterior Glenohumeral Capsular Reconstruction With Human Dermal Allograft for Multidirectional Shoulder Instability

Recurrent multidirectional shoulder instability is a common clinical presentation in certain demographics and sporting groups. One such demographic is patients with connective tissue disorders (CTD) such as Ehlers-Danlos syndrome (EDS), in whom shoulder pathologies are exacerbated owing to ligamentous laxity. Features of this laxity can present as both anterior and posterior shoulder instability, which are problematic sources of shoulder pain. Many patients with these injuries require surgical anterior and/or posterior glenohumeral reconstruction. Surgical reconstruction for posterior capsular defects can be challenging and has higher failure rates compared with anterior capsular reconstruction methods. Management can be especially difficult for patients with CTDs, and there is a requirement for the development of novel surgical techniques. Human acellular dermal allografts have been found to be particularly useful for patients with CTDs compared with other methods that use the patient’s own tissue for the repair. This note and surgical video describe an all-arthroscopic technique for a combined anterior capsule augmentation and posterior glenohumeral capsular reconstruction, using a human acellular dermal allograft for EDS patients with multidirectional instability.

Intrauterine versus post-mortem magnetic resonance in second trimester termination of pregnancy for central nervous system abnormalities

ObjectiveTo evaluate if limiting factors of intrauterine magnetic resonance imaging (iuMRI) performed in the early second trimester of pregnancy (19–23 weeks) affect its accuracy in comparison to post-mortem MRI (pmMRI) in fetuses that underwent termination of pregnancy (TOP) for central nervous system (CNS) defects. Study designThis is a secondary analysis of a 10 years prospective observational study. Cases of TOP < 23 weeks for CNS malformation that had undergone neurosonography (NSG), iuMRI, pmMRI and autopsy were included. The agreement between iuMRI and pmMRI was calculated. The autopsy represented the gold-standard. ResultsOverall, 143 TOPs for fetal congenital anomaly underwent the post-mortem diagnostic protocol. Of these, 31 cases underwent iuMRI and pmMRI for CNS abnormality. Three cases were excluded due to brain autolysis at autopsy. Corpus callosum defects were the most represented (16/28; 57 %). In only one case of posterior fossa defect, pmMRI identified the presence of vermian hypoplasia not diagnosed at iuMRI. In 2 cases (7%), iuMRI added clinically relevant additional findings to NSG, that were posteriorly confirmed by pmMRI. ConclusionsThe study shows that, at 19–23 weeks and for CNS defects, limiting factors that might influence the performance of iuMRI have little influence on iuMRI accuracy. This finding is particularly important for professionals who work in countries with legal bound for TOP in the early second trimester.

A new approach for spinal deformity patients with meningomyelocele: reverse Y incision

We report a new surgical incision for spinal deformity in patients who had undergone meningomyelocele closure surgery. Six patients underwent kifectomy using an inverse Y incision. They all had multiple prior operations in the lumbar region due to dural meningomyeloceles. Four of the patients were girls. The primary indication for the reverse Y incision was a T12 and above posterior fusion defect and a large lumbar posterior fusion defect. These patients included four with kyphoscoliosis, one with lordoscoliosis, and one with lumbar kyphosis. The median age of the patients was 5.52 at the time of operation. The median follow up time was 17.3 months. Under appropriate indication, the reverse Y approach offers a reliable and successful solution for surgery.

The Effect of Parathyroid Hormone Analogues When Added to Mineralized Bone Xenografts.

Implants can be a treatment option when there is sufficient quantity and quality of bone to provide support for long-term success. In the reconstruction of defects, autogenous bone remains the gold standard for its osteogenic and compatibility properties. However, the disadvantage of secondary surgery and the associated donor site morbidity prompts researchers to develop the ideal bone substitute for optimum bone reconstruction. Parathyroid hormone (PTH1-34) has provided a new option for improvement in bone regeneration. This study used a pig model to evaluate the effectiveness of parathyroid hormone when added to a xenograft, Bio-Oss, in reconstructing mandible defects. Six domestic pigs were used to create 3 posterior mandibular defects measuring 2 × 1-cm bilaterally with a total of 36 defects to simulate tooth extraction sites in humans. The defects were grafted in random order and divided into 3 groups as follows: control (no graft), Bio-Oss without PTH, and Bio-Oss with PTH. Defects were assessed with cone beam computerized tomography (CBCT), micro computerized tomography (microCT), nanoindentation, and histology. Results showed that adding PTH1-34 significantly enhanced the graft construct. CBCT showed a significant increase in the degree of bone mineralization. Nanoindentation showed increased hardness of regenerated bone and accelerated bone mineralization with PTH. MicroCT analysis revealed a trend toward higher bone regeneration and mineralization. The histological analysis showed a positive trend of the increase in cortical bone thickness and mineral apposition rate. In conclusion, the local addition of PTH1-34 to a xenograft has shown promising results to enhance bone regeneration in the reconstruction of mandibular defects.

Metaphyseal cones in revision total knee arthroplasty: The role of stems.

AimsMetaphyseal tritanium cones can be used to manage the tibial bone loss commonly encountered at revision total knee arthroplasty (rTKA). Tibial stems provide additional fixation and are generally used in combination with cones. The aim of this study was to examine the role of the stems in the overall stability of tibial implants when metaphyseal cones are used for rTKA.MethodsThis computational study investigates whether stems are required to augment metaphyseal cones at rTKA. Three cemented stem scenarios (no stem, 50 mm stem, and 100 mm stem) were investigated with 10 mm-deep uncontained posterior and medial tibial defects using four loading scenarios designed to mimic activities of daily living.ResultsSmall micromotions (mean < 12 µm) were found to occur at the bone-implant interface for all loading cases with or without a stem. Stem inclusion was associated with lower micromotion, however these reductions were too small to have any clinical significance. Peak interface micromotion, even when the cone is used without a stem, was too small to effect osseointegration. The maximum difference occurred with stair descent loading. Stress concentrations in the bone occurred around the inferior aspect of each implant, with the largest occurring at the end of the long stem; these may lead to end-of-stem pain. Stem use is also found to result in stress shielding in the bone along the stem.ConclusionWhen a metaphyseal cone is used at rTKA to manage uncontained posterior or medial defects of up to 10 mm depth, stem use may not be necessary.Cite this article: Bone Joint Res. 2020;9(4):162–172.

Ultrasound Biomicroscopy Detects Peters' Anomaly and Rieger's Anomaly in Infants.

Aim Congenital corneal opacities (CCOs) are the major causes of early visual deprivation in infants. Balloon ultrasound biomicroscopy (UBM) examination is an effective method to diagnose CCO. However, whether it is suitable for children examination is still unknown. Methods 26 Peters' anomaly (PA) or Rieger's anomaly (RA) infants with congenital corneal opacities (CCO) (40 eyes) underwent UBM examinations to study their imaging features. Results Based on the results, they were divided into UBM Dx-Type I: Descemet's membrane (DM) and endothelium have heterogenous or discontinuous echo accompanied with corneal stroma echo-enhanced or shallow anterior chamber. Type II: Type I alteration plus abnormal strand of iris extended to the border of the posterior corneal defect or iridocorneal adhesion. Type III: Type I or II combined with the abnormal hyperechoic lens, lens luxation, or keratolenticular adhesion. Type IV: echoes of the DM and the endothelium are continuous, corneal stroma echo is enhanced, and an abnormal strand of peripheral iris extends to the prominent Schwalbe line, accompanied by iris stroma or pupil heteromorphism and a shallow or flat anterior chamber. Conclusion UBM not only could accurately evaluate the anterior segment abnormalities in CCO infants but also would be a step forward for the management of PA- and RA-associated CCO.

Modified Yasui Operation Using Cryopreserved Femoral Vein Homograft

The Yasui operation is indicated in an interrupted aortic arch and a posterior malaligned ventricular septal defect with a narrow subaortic region. We present a modification of the Yasui procedure in which the aortic reconstruction was simplified using a nonvalved cryopreserved femoral vein homograft to connect the pulmonary artery to the descending aorta. A side-to-side anastomosis was performed between the femoral vein homograft and ascending aorta to complete the neoaortic reconstruction. After baffling the left ventricle to the pulmonary artery with a patch, a valved segment from the same femoral vein homograft was used to restore continuity of the right ventricular outflow.

Clinical Characteristics and Surgical Safety in Congenital Cataract Eyes with Three Pathological Types of Posterior Capsule Abnormalities.

Purpose To observe the clinical characteristics of 3 pathological types of posterior capsule abnormalities (PCAs) in congenital cataracts (CCs) and evaluate the surgical safety in these eyes. Methods This study involved 239 children (367 eyes) with CC who underwent cataract surgery at the Eye Hospital of Wenzhou Medical University. All surgery videos were collected for detailed reviews. Intraoperative and postoperative complications (within 3 months) were all recorded. Results The 3 pathological types of PCAs, namely, persistent fetal vasculature (PFV), posterior capsule defect (PCD), and posterior lenticonus (PLC), presented in 129 (35.1%) CC eyes, while 238 (64.9%) eyes were recorded as CC without PCA. The percentages of PFV, PCD, and PLC were 10.9%, 26.7%, and 5.4% in CC eyes (n = 367), respectively. The most common concomitant of PFV eyes was PCD (42.5%), and PFV was the most frequent (17.3%) one in PCD eyes. PLC was only associated with PFV (15%) and PCD (50%). The occurrence rates of surgical complications ranged from 0 to 5.4%, and no statistical difference was found between the eyes with and without PCA (all P > 0.05). Conclusions PFV, PCD, and PLC play a very important role in the CCs. The effect of fetal vessels in PFV eyes might be an abnormally strong attachment on the posterior capsule, leading to PLC and PCD. Even in PCA patients, severe surgical complication can also be avoided with well-designed and skilled operation. This trial is registered with NCT03905044 at http://ClinicalTrials.gov.

Prevalence of posterior alveolar bony dehiscence and fenestration in adults with posterior crossbite: a CBCT study

BackgroundCorrecting posterior crossbite in adult patients using nonsurgical methods may involve buccolingual tooth movement. Knowing the extent of the pretreatment alveolar bony dehiscences and fenestrations in the posterior area will aid orthodontists in planning posterior crossbite patients accordingly to minimize posttreatment bony defects. Before the advent of cone beam computed tomography (CBCT), observing buccal and lingual bony defects was not possible unless other treatment needs allowed for an open-flap procedure. With CBCT technology, we can now detect posterior defects with some accuracy. The aim of the present study was to determine the prevalence of posterior alveolar bony dehiscence and fenestration in adults with posterior crossbite compared with noncrossbite adults.MethodsThe study group consisted of pretreatment CBCTs of 28 samples with at least one or more teeth in posterior crossbite or edgebite. The comparison group consisted of pretreatment CBCTs of 28 samples with no posterior crossbite or edgebite. All buccal and lingual sides of the upper and lower posterior segments were measured for the presence of dehiscence, fenestration, and combined total bony defects.ResultsThe prevalence of total bony defects was higher in the study group (61.6%) than in the comparison group (52.1%) (p < 0.05). While there was no difference in prevalence between crossbite teeth in the study group and noncrossbite teeth in the comparison group, the noncrossbite teeth in the study group showed a higher prevalence of total bony defects, dehiscence, and fenestration than the noncrossbite teeth in the comparison group (p < 0.05). The prevalence of dehiscence was higher in the study group (41.2%) than in the comparison group (33.3%) (p < 0.05). Neither the prevalence of fenestration nor the mean bony defect size showed statistical significance between the two groups. First premolars showed a higher prevalence of dehiscence than other posterior teeth, and maxillary posterior teeth had a higher prevalence of fenestration than mandibular posterior teeth. Among the maxillary posterior teeth, second premolars had the least amount of fenestration.ConclusionsAdult subjects with posterior crossbite had a higher prevalence of total bony defects and dehiscence, especially buccal dehiscence, in the posterior region than subjects with no posterior crossbite. This was due to the high prevalence observed in the noncrossbite teeth in posterior crossbite subjects.