Maxillary Segment Research Articles

Bilateral Maxillary Duplication in Tessier No. 7 Cleft: An Uncommon Congenital Deformity with a Challenging Radiological Diagnosis.

Tessier No. 7 cleft, known as lateral facial cleft, is a rare and understudied entity with an incidence of 1/80,000-1/300,000 live births. Besides perioral tissue abnormalities manifesting as macrostomia, Tessier 7 cleft also involves anomalies of the underlying bony structures. It can appear as part of a syndrome, such as Treacher-Collins syndrome or Goldenhar/Orbito-Auriculo-Vestibular Spectrum, or as an isolated form (unilateral or bilateral) with variable expressions. Bilateral maxillary duplication in Tessier 7 cleft is considered extremely rare, accounting for only two previously presented cases. Given that the cases presented in the literature mainly focus on clinical appearance and surgical treatment, without providing sufficient imaging, we aim to present key radiological features of Tessier 7 cleft in terms of evaluating the involved structures, which is essential for the therapeutic approach and final outcome. A 17-year-old male with incompetent lips and orthodontic abnormalities was referred to our Radiology Department for orthopantomography (OPG) and CT examinations. Hetero-anamnestic data revealed a history of surgical treatment of the commissural cleft conducted 2 months after the birth to enable feeding. Intraoral examination showed a maxillary cleft and supernumerary teeth. Since the given clinical presentation was inconclusive, radiological diagnostics took precedence in elucidating this complex entity.

Artificial intelligence system for automatic maxillary sinus segmentation on cone beam computed tomography images.

The study aims to develop an artificial intelligence (AI) model based on nnU-Net v2 for automatic maxillary sinus (MS) segmentation in Cone Beam Computed Tomography (CBCT) volumes and to evaluate the performance of this model. In 101 CBCT scans, MS were annotated using the CranioCatch labelling software (Eskisehir, Turkey) The dataset was divided into three parts: 80 CBCT scans for training the model, 11 CBCT scans for model validation, and 10 CBCT scans for testing the model. The model training was conducted using the nnU-Net v2 deep learning model with a learning rate of 0.00001 for 1000 epochs. The performance of the model to automatically segment the MS on CBCT scans was assessed by several parameters, including F1-score, accuracy, sensitivity, precision, Area Under Curve (AUC), Dice Coefficient (DC), 95% Hausdorff Distance (95% HD), and Intersection over Union (IoU) values. F1-score, accuracy, sensitivity, precision values were found to be 0.96, 0.99, 0.96, 0.96 respectively for the successful segmentation of maxillary sinus in CBCT images. AUC, DC, 95% HD, IoU values were 0.97, 0.96, 1.19, 0.93, respectively. Models based on nnU-Net v2 demonstrate the ability to segment the MS autonomously and accurately in CBCT images.

Is three-piece maxillary segmentation surgery a stable procedure?

: The number of three-piece maxillary osteotomies has increased over the years; however, the literature remains controversial. The objective of this study was to evaluate the skeletal stability of this surgical modality compared with that of one-piece maxillary osteotomy. : This retrospective cohort study included 39 individuals who underwent Le Fort I maxillary osteotomies and were divided into two groups: group 1 (three pieces, n = 22) and group 2 (one piece, n = 17). Three cone-beam computed tomography scans from each patient (T1, pre-surgical; T2, post-surgical; and T3, follow-up) were used to evaluate the three-dimensional skeletal changes. : The differences within groups were statistically significant only for group 1 in terms of surgical changes (T2-T1) with a mean difference in the canine region of 3.09 mm and the posterior region of 3.08 mm. No significant differences in surgical stability were identified between or within the groups. The mean values of the differences between groups were 0.05 mm (posterior region) and -0.39 mm (canine region). : Our findings suggest that one- and three-piece maxillary osteotomies result in similar post-surgical skeletal stability.

Maxillary bone healing and CT value after Le Fort I osteotomy using absorbable plate system: A retrospective study

This study aimed to evaluate maxillary bone healing and computed tomography (CT) values after Le Fort I osteotomy with sagittal split ramus osteotomy in patients with class II and III malocclusion. Four absorbable plates and screws were used to fix the maxillary segments in all patients. For 112 sides (58 patients), the bone defect areas at the anterior and posterior sites between the maxillary segments were measured using 3-dimensional CT views reconstructed over a constant CT value at 1 week and 1 year postoperatively. Subsequently, CT values at the upper, middle, and lower sites around the osteotomy line in the medial, middle, and lateral regions were measured. The bone defect area after 1 year increased at the anterior site in class III and at both the anterior and posterior sites in class II (P < 0.05). This study suggests that the increase in bone defect area was affected by lower CT values at the middle site of the middle and lateral regions in class II, and that bony defects between fragments in the maxilla could partially remain in both classes II and III within 1 year after Le Fort I osteotomy.

Oroantral Communication After Segmental Le Fort I Osteotomy.

Segmental Le Fort I osteotomy is a very versatile technique for correcting mainly transverse discrepancies of the maxilla. However, there are possibilities of intraoperative and intraoperative complications. This article reports a case of oral-antral communication after maxillary segmentation with intraoperative identification and correction using the rotation of the palatal flap. The surgeon needs to know such possible complications when performing the technique to identify and correct them promptly to avoid further sequelae to the patient.

Evaluation of Dimensional Changes in Maxillary and Frontal Sinus in Adult Patients With Anterior Open Bite and Normal Overbite: A Retrospective Cone Beam Computed Tomography (CBCT) Study.

An anterior open bite is a form of vertical discrepancy that presents as a lack of contact between maxillary and mandibular segments. The treatment modalities usually involve either intrusion of posterior teeth or extrusion of anterior or a combination of both. The anatomical relationship between the apex of the maxillary molar roots to the inferior wall of the maxillary sinus floor is crucial in planning posterior intrusion. The paranasal sinuses influence the growth of the facial structures that eventually get altered in various malocclusions. Studies have proven that theheight of the sinusgets modified in anterior open bite owing to pneumatization. This study aims to evaluate the distance from the root apex of maxillary first molars (mesiobuccal, distobuccal, and palatal roots) to the maxillary sinus floor to evaluate the significance of the vertical pneumatization of the sinus on planning for true intrusion in anterior open bite and to assess the correlation between frontal and maxillary sinuses in an anterior open bite. This retrospective study evaluated 30 pre-treatment cone beam computed tomographies (CBCTs) of patients out of which 15 were with anterior open bite and 15 with ideal overbite. Linear measurements were carried out using care stream software in CBCTs. There was a significant correlation between the distance of the palatal root and the distobuccal root of the maxillary first molar to the maxillary sinus floor bilaterally in the anterior open bite (p<0.04). A significant moderate positive correlation of the maxillary and frontal sinus height in anterior open bite (p<0.006). A significant moderate negative correlation between the distance from the palatal root to the maxillary sinus floor and maxillary sinus height in anterior open bite (p<0.001). Vertical pneumatisation of the maxillary sinus has caused a significant negative correlation between the apex of the palatal root of the maxillary first molar tooth and the maxillary sinus floor in the anterior open bite. The palatal root being the closest to the sinus floor, and the distobuccal root being second nearest. There is a significant correlation between the height of the sinuses in the anterior open bite.

Cephalometric and digital model analysis of dentoskeletal effects of infrazygomatic miniscrew vs. Essix- anchored Carriere Motion appliance for distalization of maxillary buccal segment: a randomized clinical trial

Trial designParallel.ObjectiveTo compare skeletally anchored Carriere Motion appliance (CMA) for distalization of the maxillary buccal segment vs. Essix anchored CMA.MethodsThirty-two class II malocclusion patients were randomly allocated into two equal groups. One group was treated with infrazygomatic (IZC) miniscrew- anchored CMA (IZCG) and the other group treated with Essix retainer- anchored CMA (EXG). Two lateral cephalograms and two digital models for upper and lower arches were taken for each patient: immediately before intervention and after distalization had been completed.ResultsDistalization period was not significantly different between the two groups. In contrast to EXG, IZCG showed insignificant difference in ANB, lower incisor proclination, and mesial movement of the lower first molar. There was significant rotation with distal movement of maxillary canine and first molar in both groups.ConclusionIZC anchored CMA could eliminate the side effects of class II elastics regarding lower incisor proclination, mesial movement lower molars with a more significant amount of distalization of the maxillary buccal segment but with significant molar rotation.Trial registrationThe ClinicalTrials.gov Protocol Registration and Results System (PRS) has this RCT registered as (NCT05499221) on 12/08/2022.

Mandibular canine development as an indicator of maxillary cleft site canine development

Objectives: The objective of this study was to determine if mandibular canine development is an indicator of maxillary cleft site canine development. Material and Methods: A cross-sectional chart review with analysis of cone-beam computed tomography (CBCT) imaging of patients aged 7–12 with a unilateral complete cleft lip and palate who received alveolar bone graft surgery from January 2009 to January 2019. Three-dimensional (3D) measurements of the cleft site canine and ipsilateral mandibular canine were taken. A two-dimensional image was created from the 3D CBCT to simulate a traditional panoramic radiograph. Descriptive statistics and multivariable linear regression analyses were conducted, adjusting for age and gender. Pearson and Spearman correlations were calculated. The main outcome measure was the mandibular canine crown-to-root ratio (C:RR) compared to that of the maxillary cleft site canine C:RR. Results: Five hundred and thirteen patients were reviewed, of which 78 met the inclusion criteria. Adjusting for age and gender, every unit change in mandibular canine C:RR corresponds to 0.69 (95% confidence interval [CI] = 0.42–0.95) change in maxillary canine C:RR, up to a mandibular canine C:RR of 3. Beyond a mandibular C:RR of 3, no change in the maxillary canine C:RR was observed (−0.02; 95%CI = −0.27–0.24). Pearson correlation coefficient was r = 0.65, and the Spearman correlation was P = 0.75. Conclusion: Mandibular canine C:RR is correlated to maxillary cleft site canine C:RR when the mandibular canine C:RR is ≤3.

Histomorphometric Comparison of Bio-Oss vs. Osteodens in Maxillary Sinus Floor Elevation Procedures

Introduction: The loss of dental elements can lead to excessive bone loss in the posterior maxillary segments, which can limit the placement of dental implants in that area, the pneumatization of the maxillary sinus and the absence of dental elements to keep the bone active are some of the main causes. Among the wide range of available grafting materials, bovine hydroxyapatite has been extensively studied and has shown excellent clinical and histological results. Materials and methods: A total of 17 maxillary sinus floor elevations were performed (n = 8 Osteodens, n = 9 Bio-Oss). After a healing period of 6 to 8 months, a block of the grafted area was obtained using trephines and analyzed by histomorphometry. Results: The percentage of neoformed bone tissue was higher for Bio-Oss (39.0% ± 11.1) compared to Osteodens (33.4% ± 8.3), while the remaining graft values were slightly lower in Bio-Oss compared to Osteodens (16.3% ± 11.2 and 20.8% ± 12.1, respectively). The proportion of connective tissue was similar in both groups (44.7% Bio-Oss and 45.8% Osteodens). Age, gender, and residual height of the sinus floor did not show statistically significant differences. Conclusions: In this study, both graft materials (Bio-Oss and Osteodens) showed no statistically significant differences in their ability to regenerate suitable bone tissue for implant placement after 6 months of healing. Further studies with a larger sample size are needed to validate these results.

Diagnosis and Treatment of a Case of Maxillary Cleft in a Cat Associated with Pulmonary Emphysema

Maxillary cleft in cats often occurs due to high-altitude falls, resulting in trauma and pulmonary emphysema. Clinically, it is characterized by oral and nasal bleeding and is classified into congenital and acquired types, with its etiology being related to husbandry practices. This paper presents a case of maxillary cleft in a cat associated with pulmonary emphysema. After initial symptom observation and inquiry, a definitive diagnosis was made through clinical examination, laboratory tests, and X-ray imaging. Treatment involving medication and surgery was administered, followed by an evaluation of its effectiveness. Given the limited literature on this condition and its increasing incidence, this case contributes to the guidance of diagnosis and treatment for cats with maxillary cleft associated with pneumothorax.

Computer-assisted assessment of segmental bimaxillary surgery using voxel- and surface-based registration: A comparative study

The purpose of the present study was to compare the precision and reliability of voxel- and surface-based registration for computer-assisted assessment of the surgical accuracy and postoperative stability of segmental bimaxillary surgery. Three-dimensional translational and rotational measurements were performed by two observers using voxel- and surface-based registration. The precision and reliability of the measurements were calculated by the mean absolute differences (MAD) and intraclass correlation coefficients (ICC) at 95 % confidence intervals. A paired t-test or the non-parametric equivalent, Wilcoxon signed-rank test, was applied to statistically evaluate whether the precision of voxel- and surface-based registration was statistically significantly different (p < 0.05). Voxel-based registration had high precision (MAD <0.44 mm/0.92°) and excellent reliability, ICC [0.82–1.00]. The precision of surface-based registration was lower (MAD <0.56 mm/1.45°) and the reliability ranged from poor to excellent for the different bone segments, ICC [0.33–1.00]. Both registration techniques had high precision and excellent reliability for the assessment of the surgical accuracy, and the error margin of both techniques was clinical irrelevant. However, the increased precision of voxel-based registration was statistically significant (p < 0.05) for the maxillary segments and the chin, and the stability measurement error (ranging up to 1.58 mm and 4.46°) introduced by surface-based registration may be considered clinical relevant for these bone segments. Within the limitations of the present comparative study, voxel-based registration generally exhibited higher precision and reliability than surface-based registration for the surgical accuracy and postoperative stability assessment of segmental bimaxillary surgery.

Presurgical orthopedics in patient with cleft lip and palate without cheiloplasty at one year of age.

Introduction. Cleft lip/palate (CLP) occurs due to failure of fusion of facial processes at an early stage of embryonic development. The use of pre-surgical orthopedics helps us to correct the bone collapse that patients with CLP may present, as well as stimulate the growth of the palatal segments, with use beginning in the first hours of life. Due to the pandemic caused by COVID, many patients did not receive care, generating a need for treatment focused on their characteristics. Aim. Generate transversal development in a 1-year-old male patient and rotate the left maxillary segment to conform the arch, and thus, favor the prognosis of surgery for the patient with cleft lip and palate without cheiloplasty at one year of life. Description of the case. Male patient with cleft lip and palate without cheiloplasty at one year of age presents to cleft lip and palate clinic YOU HAVE TO SMILE, JOIN EFFORTS. He refers to having been treated with pre-surgical orthopedics. Clinically, a cleft lip and palate is observed, in addition to the collapsed left maxillary segment, generating a lack of continuity and arch perimeter. The treatment phase consisted of a removable plate joined in its central part by three helixes, to rotate the left maxillary segment. Results. An adequate maxillary development was generated and the arch was shaped. conclusions. It is important to highlight the characteristics of each case in order to generate a treatment plan suitable for the needs of the patient, since this improves the prognosis and post-surgery.

Effects of direct pulp capping with recombinant human erythropoietin and/or mineral trioxide aggregate on inflamed rat dental pulp.

This study aimed to evaluate the dental pulp responses to recombinant human erythropoietin (rhEPO) and/or mineral trioxide aggregate (MTA) in pulp capping of inflamed dental pulp in vivo. In accordance with ARRIVE guidelines, pulp inflammation was induced by exposing the maxillary first molars (n = 64) of Wistar rats (n = 32) to the oral environment for two days. The exposed pulps were randomly assigned four groups based on the pulp capping material: rhEPO, MTA, MTA + rhEPO, or an inert membrane. An additional eight rats formed the healthy control group. After four weeks, the animals were euthanized, and histological, qRT-PCR, and spectrophotometric techniques were employed to analyze the left maxillary segments, right first maxillary molars, and blood samples, respectively. Statistical significance was set at p < 0.05 and < 0.001. Pulp capping with rhEPO, MTA, or MTA + rhEPO resulted in lower inflammation and higher mineralization scores compared to untreated control. MTA + rhEPO group exhibited significantly decreased expression of tumor necrosis factor-alpha, and interleukin 1-beta, while MTA group showed substantially reduced expression of interferon-gamma. Both rhEPO and MTA + rhEPO groups presented elevated dentin matrix protein 1 levels compared to untreated control. Furthermore, pulp capping with rhEPO and/or MTA led to increased transforming growth factor-beta 1 expression and reductions of pro-inflammatory/immunoregulatory cytokine ratios and prooxidative markers. Pulp capping with rhEPO also resulted in increase of systemic antioxidative stress markers. Capping with rhEPO or MTA + rhEPO resulted in a favorable effect that was similar or even superior to that of MTA.

Three-dimensional evaluation of skeletal stability after surgery-first bimaxillary surgery for class III asymmetry in 70 consecutive patients

Background/purposeSkeletal stability after orthognathic surgery is essential for positive treatment outcome. This study evaluated the stability of osteotomy segments after surgery-first bimaxillary surgery for class III asymmetry. Materials and methodsSeventy adults with class III asymmetry consecutively corrected through surgery-first Le Fort I and bilateral sagittal split osteotomies were investigated. Cone-beam computed tomography before treatment (T0), 1-week after surgery (T1), and after all treatment (T2, ≥1-year after surgery) was used to assess surgical movement (T0 to T1) and skeletal stability (T1 to T2) regarding the translation and rotation of the maxillary, mandibular distal, and proximal segments. ResultsAt T1, the maxillary segment had moved forward and upward, turned to the deviated side, and rotated downward (all P < 0.01). The distal segment of mandible had moved forward and upward and rotated upward (all P < 0.001). The deviated proximal segment had moved upward, tilted to the opposite side, and rotated upward (all P < 0.001). The opposite proximal segment had moved upward and tilted to the deviated side (both P < 0.01). At T2, significant relapse occurred in the mandible. The distal segment moved forward and upward and rotated upward (all P < 0.001). The deviated proximal segment moved upward, tilted to the opposite side, and rotated upward (all P < 0.001). The opposite proximal segment moved upward and tilted to the deviated side (both P < 0.01). ConclusionClinically significant relapse of class III asymmetry was discovered on the mandibular distal and opposite proximal segments.

Esthetic rehabilitation of mutilated maxillary anterior alveolar segment by combining orthodontic osseous distraction and implant-supported crowns: A clinical report

Bony defects in the esthetic zone, especially in the maxillary anterior region, increase the complexity of surgical and prosthetic procedures. Moving teeth with preprosthetic osseous distraction techniques can be an alternative nonsurgical option to traditional regenerative or reparative surgical therapies to increase bone volume. Healthy peri-implant bone, periodontium, and adjacent teeth provide a favorable environment for implant restorations. The esthetic rehabilitation of the maxillary region after the removal of 2 ankylosed central incisors is presented. The lateral incisors were moved mesially to the central incisor positions, and implants placed in the lateral incisor positions after new healthy bone had been induced.

Nasolabial soft tissue changes associated with posterior maxillary movement following anterior segmental osteotomy in skeletal Class II patients: A case series

ObjectiveThis study investigated the relationship between the external nasal morphology and hard tissue movement in patients who underwent anterior segmental maxillary osteotomy (ASMO) to correct maxillary protrusion correction. MethodsThe study enroled patients with an overjet ≥ 5 mm, and an ANB ≥ 2° who underwent ASMO with or without Le Fort I osteotomy. Linear and angular measurements were performed on computed tomography images obtained preoperatively and one year post-surgery. ResultsThe movement of the maxilla at U1 was 6.7 ± 2.9 mm backward and 1.9 ± 2.0 mm upward. Tooth axis inclination of U1 (∠U1 to FH) increased 5.5 ± 6.1°. The nasolabial angle significantly increased from 90.0 ± 16.8° to 101.0 ± 13.2°. No significant differences were observed in alar base width or nasal tip angles. The change of ∠U1 to FH and the backward movement of U1 were relevant factors influencing the change of nasolabial angle. ConclusionsThis study provides insights into the relationship between external nasal morphology and posterior movement of the anterior maxillary segment after ASMO surgery. These findings are significant for predicting post-operative patient profiles.

Iterative learning for maxillary sinus segmentation based on bounding box annotations

Iterative learning for maxillary sinus segmentation based on bounding box annotations

Comparison between two types of grids for placement of mini-screw implant in posterior maxillary segment

Use of mini-screw implants is in vogue. It has brought about a drastic change in day to day practise for orthodontists. Despite being the most popular source of anchorage, it is not easy for newer clinicians to perfectly figure out the site of implant placement and the accuracy by which it should be placed to avoid failure. A customised grid or mesh is the simplest way to gain assistance for placement of miniscrew implants. This article focuses on comparison of two types of grids for placement of implant accurately and to guide the clinician in such a way that minimises all the possible errors.

Assessing the Pros and Cons of Performing Orthognathic Surgery in Patients Undergoing Orthodontic Aligner Treatment

Objective: Orthodontic aligners have become one of the most requested treatments by patients. This study evaluated maxillofacial surgeons´ experience of using orthodontic aligners in preparation for orthognathic surgery.&#x0D; Methods: A survey using an online platform was used to identify some key points about maxillofacial surgeons´ prior experiences with orthodontic aligners in the context of orthognathic surgery. Participants were asked to discuss their experience with orthognathic surgery preparation through orthodontic aligners.&#x0D; Results: In total, 396 surveys were sent, the sample consisted of 92 respondents. The experience of maxillofacial surgeons on this topic is not very large, some of them (45.65%) have not had contact with orthodontic aligners. Advantages include patient convenience and easy postoperative hygiene, while some disadvantages include inefficient postoperative occlusal stability and intermaxillary block and some difficulties in using elastic bands. A very helpful explanation to solve some problems was highlighted by the surgeons, including a more detailed conference on orthodontic preparation. Maxillary segmentation must be avoided according to the majority of surgeons.&#x0D; Conclusion: The results of the study indicate that not all cases are suitable for orthognathic surgery prepared with orthodontic aligners. While orthodontic aligners offer advantages such as patient-friendliness and improved hygiene, the lower number of surgeons reporting these benefits compared to the disadvantages underscores challenges related to postoperative occlusal stability and limitations with intermaxillary blocks and elastic band usage.

Objective assessment of visual attention in orthognathic surgery training based on eye tracking

The aim of this study was to investigate the differences in visual attention between novices and orthognathic experts, as well as to provide evidence for use in developing and optimizing training strategies for orthognathic surgery.Novice and orthognathic experts were recruited, and their distributions of visual attention were monitored via an eye-tracking device while they watched orthognathic surgery videos. The percentages of visual fixation duration devoted to the areas of interest — surgical objects, instruments controlled by the main surgeon, and instruments controlled by the assistants — in each orthognathic surgery section were analyzed and compared between the two groups using repeated-measures factorial analysis of variance (ANOVA).In total, there were 18 participants, comprising both novices (n = 9) and experts (n = 9). For all sections of orthognathic surgery, the percentage of fixation duration on surgical objects was significantly higher for the novices than for the experts (p = 0.031, p = 0.005, p = 0.026, p = 0.047, p = 0.047, p = 0.031, p = 0.027, p = 0.034, p = 0.008, and p = 0.016). During the maxillary segment separation as part of Le Fort I osteotomy and the splitting of the mandible as part of bilateral sagittal split osteotomy, the novices also had a higher percentage of fixation duration on the instruments controlled by the main surgeon, as compared with the experts (p = 0.007 and p = 0.048, respectively).Novices invested great cognitive effort into the surgical objects in each section of orthognathic surgery, including the instruments controlled by the main surgeon in the maxillary segment separation and the splitting of the mandible. Strengthening this aspect of instruction could help novices reduce their cognitive load and achieve mastery more efficiently.