CAD/CAM and conventional reconstruction of the mandibular condyle by fibula free flap: a clinical and radiological evaluation

The aim of this study was to analyse the radiological and clinical outcomes of condylar reconstruction by fibula free flap (FFF), comparing conventional freehand and CAD/CAM techniques. Fifteen patients (nine CAD/CAM, six freehand) who underwent condylar reconstruction with a FFF were reviewed retrospectively regarding pre- and postoperative computed tomography/cone beam computed tomography scans and clinical function. After surgery, all patients were free of temporomandibular joint pain. Mean postoperative mouth opening was 30.80 mm, with no significant difference between the freehand and CAD/CAM groups. In all patients, laterotrusion was decreased to the contralateral side (P = 0.002), with no difference between freehand and CAD/CAM, while the axis of mouth opening deviated to the side of surgery (P < 0.001). All patients showed significant radiological deviation of the fibular neocondyle in the laterocaudal direction (lateral: P = 0.015; caudal: P = 0.001), independent of the technique. In conclusion, reconstruction of the mandibular condyle by FFF provided favourable functional results in terms of mouth opening, reduction of pain, and mandibular excursions. Radiological deviation of the neocondyle and deviation of laterotrusion and mouth opening did not impair clinical function. CAD/CAM planning facilitated surgery, decreased the surgery time, and improved the fit of the neocondyle in the fossa.     

Free fibula flap for reconstruction of the severely atrophic mandible: a retrospective study

The purpose of this retrospective study was to assess the feasibility of using a free fibula flap (FFF) for reconstruction of the alveolar region of the severely atrophic mandible, by determining bone stability after dental implant insertion and prosthetic rehabilitation in a series of eight female patients aged 36–65 years. Dental implant insertion was performed 3–4 months after reconstruction. Prosthetic loading was performed 3–4 months after implant insertion. The height of the reconstructed mandible after surgery was 21.20 ± 1.87 mm, with an increase of 8.80 ± 1.71 mm from the preoperative height. The height of the FFF immediately after reconstruction was 11.24 ± 1.10 mm; this showed a vertical loss of 0.99 ± 0.52 mm (8.79%) and maintenance of 91.21% of the initial height at a mean 14 months post-reconstruction. Applying the Wical and Swoope formula to estimate the original mandibular body height, it was found that the difference between this calculated height (21.17 ± 3.76 mm) and the reconstructed height (21.20 ± 1.87 mm) was only 0.03 ± 3.17 mm (0.14%). An overall insignificant decrease of 0.46 ± 1.14 cm³ in FFF volume had occurred at 3–4 months after dental implant functional loading, while in two cases an increase in volume was found (1.22 cm³ and 1.71 cm³). The good and stable results obtained show that the FFF may be used to reconstruct the whole mandibular alveolar region, with the best possible outcomes.     

Volumetric changes in the size of odontogenic keratocysts after decompression followed by enucleation,peripheral ostectomy,and Carnoy's solution: A retrospective study

The study aimed to retrospectively analyze the reduction pattern of odontogenic keratocysts (OKCs) after decompression, followed by enucleation (EN), peripheral ostectomy (PO), and Carnoy's solution (CS) to establish the appropriate time for inserting implants, along with assessing the long-term success of conservative treatment with adjunctive therapy. The predictable variables were the reduction pattern and the study's treatment option. The outcome variable was the volumetric changes in the size of bony defects. These changes were determined using a percentage difference and a reduction rate. They were recorded after decompression and one, three, six, twelve, and eighteen months after EN. P-values of .05 were considered significant. The study included 66 patients with 71 OKCs. Males, younger ages, and mandibular OKCs significantly predominated. The decompression significantly changed the initial volume from 135.40 ± 1.2 cm³ to 101.55 ± 0.1 cm³ with 28.6 percentage difference and 25% reduction rate. At the end of the first and third months after EN, the reduction pattern is 50.0%–75.5% of the initial volume, with no significant prediction for the direction of the reduction pattern. After 18 months, all bony defects disappeared, with no recurrences for the next 18 years. In conclusion, the reduction pattern is 75.5% of its initial volume at the end of the third month after OKC management. Therefore, within the limitations of the study, its treatment approach seems to be an option amongst other protocols that includes a view to early implant based dental rehabilitation.     

Blood clot stability and bone formation following maxillary sinus membrane elevation and space maintenance by means of immediate implant placement in humans. A computed tomography study

ObjectiveThe present controlled clinical pilot study proposed to assess blood clot contraction and bone neo-formation following maxillary sinus lift (MSL) with immediate implant placement without using grafts using cone beam tomography exams.Materials and methodsTen implants were placed in ten patients with a residual bone crest height ≥4 and ≤ 7 mm, in maxillary premolars or 1st or 2nd molars regions, using MSL and immediate implant placement without grafts, by means of the lateral window approach. A resorbable membrane (Bio-Gide®, Geistlich, USA) was used to close the window. Computed tomography images were taken after 15 (T1) and 180 (T2) days to assess the rate of blood clot contraction and bone neo-formation. The images were analysed by OsirixMD software. The Shapiro Wilk test was used to verify the normality hypothesis and the data were submitted to Student's paired t-test.ResultsThe mean of bone clot height in mesial, apical and distal area referred to implant, presented 4.77 mm, 0.77 mm and 5.30 mm respectively. The mean measurements of new bone formation presented 2.95 mm, 0.44 mm and 3.45 mm. The height contraction (coagulum/new bone formation), between T1 and T2, presented 38%, 43% and 35% respectively, with a significant statistical value p < 0.05.The volume measurements at T1 presented a mean volume of 0.90 cm³ sd ± 0.60 cm³ and at T2 a mean volume of 0.75 cm³ sd ± 0.62 cm³, with a significant volume contraction between T1 and T2, p < 0.005. The mean blood clot contraction was 16.52% ± 8.60%.ConclusionThe present study demonstrates consistent bone formation around all assessed implants, although with significant contraction of the blood clot. The need for longitudinal studies to establish a long-term prognosis in different modalities of prosthetic rehabilitation of those implants is strongly suggested.     

Effect of maxillary surgical movement on nasal cavity and maxillary sinus dimensions and function after Le Fort I osteotomy

This study was designed to evaluate the effects of different maxillary movements performed in Le Fort I surgery on the anatomy of the nasal cavity and maxillary sinus, occurrence of rhinosinusitis, and nasal airflow. Patients were divided into three groups: group I underwent pure advancement, group II underwent advancement with yaw rotation, and group III underwent advancement with impaction movements. All evaluations were performed using pre- and postoperative computed tomography images and surveys. Twenty-eight patients were enrolled. The mean pre- and postoperative nasal air volumes in group I were 22.74 ± 6.32 cm³ and 25.17 ± 6.19 cm³, respectively, showing a significant increase (P = 0.041). The mean pre- and postoperative maxillary sinus air volumes were 33.94 ± 13.72 cm³ and 26.28 ± 14.12 cm³ in group II and 35.29 ± 9.58 cm³ and 28.65 ± 8.42 cm³ in group III, respectively, showing significant reductions (P = 0.028 and P = 0.007, respectively). For all movements, the occurrence of septum deviation and nasal airflow impairment was not statistically significant. Pure maxillary advancement movement enhanced nasal cavity air volume. The yaw rotation movement significantly increased quantitative clinical rhinosinusitis symptoms. The risk of airflow impairment following Le Fort I surgery is low.     

Reliability of orbital volume measurements based on computed tomography segmentation: Validation of different algorithms in orbital trauma patients

PurposeTo compare the most common methods of segmentation for evaluation of the bony orbit in orbital trauma patients.Materials and methodsComputed tomography scans (before and after treatment) from 15 patients with unilateral blowout fractures and who underwent orbital reconstructions were randomly selected for this study. Orbital volume measurements, volume difference measurements, prolapsed soft tissue volumes, and bony defect areas were made using manual, semi-automated, and automated segmentation methods.ResultsVolume difference values between intact and damaged orbits after surgery using the manual mode were 0.5 ± 0.3 cm³, 0.5 ± 0.4 cm³ applying semi-automated method, and 0.76 ± 0.5 cm³, determined by automated segmentation (р = 0.216); the mean volumes (MVs) for prolapsed tissues were 3.0 ± 1.9 cm³, 3.0 ± 2.3 cm³, and 2.8 ± 3.9 cm³ (p = 0.152); and orbital wall defect areas were 4.7 ± 2.8 cm², 4.75 ± 3.1 cm², and 4.9 ± 3.3 cm² (p = 0.674), respectively.ConclusionsThe analyzed segmentation methods had the same accuracy in evaluation of volume differences between two orbits of the same patient, defect areas, and prolapsed soft tissue volumes but not in absolute values of the orbital volume due to the existing diversity in determination of anterior closing. The automated method is recommended for common clinical cases, as it is less time-consuming with high precision and reproducibility.     

Comparison of Mandibular Bone Mineral Densities in Dentate and Edentulous Patients

Purpose: In contemporary implant dentistry, bone mineral density (BMD) of the jaws is a patient‐associated prognostic factor. The aim of this study was to compare the mandibular body BMD of dentate and edentulous patients using the dual‐energy X‐ray absorptiometry (DXA) technique. Materials and Methods: A total of 39 patients, 20 dentate and 19 edentulous, were included in this cross‐sectional study. Mandibular body BMD was measured using the DXA technique. The variables were normally distributed; thus, the independent samples t‐test was used for the determination of statistical significance between the dentate and edentulous groups (age, body mass index [BMI], DXA). Chi‐square test was performed for identification of the gender differences between the groups. The Pearson correlation analysis was used to analyze the relationship between age, BMI, and mandibular body BMD. Note that p < 0.01 was accepted as the significance level. Results: There was no statistically significant difference between the dentate and edentulous groups in matching variables (age, BMI, and gender) (p > 0.01). There was a statistically significant difference regarding the mandibular body BMD in the dentate and edentulous group (p < 0.01) controlling for age, gender, and BMI. The edentulous group patients had higher mandibular body BMD values (1.27 ± 0.31 g/cm²) than those in the dentate group (0.94 ± 0.22 g/cm²). Conclusion: Comparison of the mandibular body BMD revealed that dentate patients had less dense bone than the edentulous patients. Further investigations are needed to determine the BMD of the jaws in different regions and for different systemic conditions.     

Virtual quad zygoma implant placement using cone beam computed tomography: sufficiency of malar bone volume,intraosseous implant length,and relationship to the sinus according to the degree of alveolar bone atrophy

The objective of this study was to investigate the malar bone volume and length that a zygomatic implant can engage, and the relationship to the sinus according to the degree of alveolar bone atrophy. A three-dimensional evaluation was performed using cone beam computed tomography scans from 23 patients with a totally edentulous maxilla; quad zygoma implants were virtually placed. The predictor variable was the amount of malar bone volume and length that a zygomatic implant can engage. The primary outcome variable was the relationship to the sinus according to the degree of alveolar bone atrophy. Other variables were the residual alveolar bone height to the floor of the sinus and the nasal cavity. The mean volume of malar bone engaged in this sample of 92 zygomatic implants was 0.19 ± 0.06 cm³. The implant had an extrasinus path in 60.9% of cases, a parasinus path in 25%, and an intrasinus path in 14.1%. The results suggest that the average volume of malar bone engaged by a zygomatic implant is constant regardless of implant position and the degree of alveolar bone atrophy. As alveolar atrophy increases, the trajectory of the implant becomes more parasinus and intrasinus. The examiners were able to find enough bone to adequately distribute the implants in all cases.     

Accelerated cranial distraction protocol for one-piece fronto-orbital distraction osteogenesis without bandeau in patients with craniosynostosis

This study aimed to compare the bony relapse ratios of standard and accelerated distraction protocols (ADP) in one-piece fronto-orbital distraction osteogenesis (DO).Patients with unilateral or bilateral coronal synostoses who underwent one-piece fronto-orbital DO were included. The accelerated cranial distraction protocol included a 3-day latency period and a distraction rate of 1–2 mm/day, followed by a 4-week consolidation period. Intracranial volume was measured using computed tomography (CT) before the surgery, at the end of the consolidation period, and 1 year after the removal of distractors. The intracranial volume changes and relapse ratios were calculated.This study included 32 patients; of these, 16 were included in each of the ADP and standard protocol (SP) groups. The mean ages were 1.4 years and 1.6 years in the ADP and SP groups, respectively (p = 0.895). In the ADP and SP groups, the expanded volumes were 270.9 ± 90.3 cm³ and 284.6 ± 149.7 cm³ (p = 0.91) and the growth-corrected expanded volumes were 162.1 ± 67.5 cm³ and 177.1 ± 105.2 cm³, respectively (p = 0.867). The relapse and growth-corrected relapse ratios showed no significant differences between the two groups, suggesting similar stability between the two protocols. The relapse ratios were 7.1 ± 4.8% and 7.3 ± 5.0% (p = 0.91) and the growth-corrected relapse ratios were ?3.0 ± 3.3% and ?2.4 ± 2.7%, respectively (p = 0.498).Within the limitations of the study, it seems that the ADP can shorten the distraction period without compromising stability. This may contribute to resolving the disadvantages and highlighting the advantages of DO.     

Sinus augmentation analysis revised: the gradient of graft consolidation

Objective: Graft consolidation follows a gradient that reflects the properties of bone substitutes at sites of sinus augmentation. Here we present an analytical method to investigate the process of graft consolidation taking the distance from the maxillary host bone into account. Material and methods: We therefore evaluated histological specimens, 6 and 12 weeks after the sinus of minipigs was augmented with Bio‐Oss^®, a deproteinized bovine bone mineral, and Ostim^®, an aqueous paste of synthetic nanoparticular hydroxyapatite. A curve was drawn that represents the changes in histomorphometric parameters within a given distance from the maxillary host bone. Results: Based on this curve, three regions of interest were defined: R1 (0–1 mm) the bridging distance where new bone is laid onto the host bone, R2 (2–3 mm) a region of osteoconduction where new bone exclusively grows on the biomaterial, R3 (4–5 mm) and a region of osteoconduction where bone formation has reached its maximal extension. Qualitative and quantitative analysis of the three regions can reveal differences in graft consolidation, depending on the bone substitutes and the observation period [Bone volume (BV) per tissue volume after 6 weeks: R1: 19±8.4% for Bio‐Oss^® and 42.9±13.2% for Ostim^® (P=0.03), R2: 3±2.4% for Bio‐Oss^® and 14.7±9.5% for Ostim^® (P=0.03), R3: 5±4.1% for Bio‐Oss^® and 5.3±5.3% for Ostim^® (P=0.86). BV per tissue volume after 12 weeks: R1: 38.0±13.3% for Bio‐Oss^® and 53.3±6.6 for Ostim^® (P=0.04), R2: 14±12.2 for Bio‐Oss^® and 26.4±11 for Ostim^® (P=0.18), R3: 6.6±7 for Bio‐Oss^® and 10.7±5.8 for Ostim^® (P=0.32) after 12 weeks]. Conclusion: Based on the graft consolidation gradient, the impact of bone substitutes to modulate the process of bone formation and the kinetic of degradation within a distinct region of the augmented sinus can be investigated.     

Influence of the anatomical form of the posterior maxilla on the reliability of superior maxillary repositioning by Le Fort I osteotomy

Certain patients with facial deformities require superior repositioning of the maxilla via Le Fort I osteotomy; however, the magnitude of superior repositioning of the maxilla is often less than expected. In this study, the correlation between the accuracy of superior repositioning of the maxilla and the anatomical form of the maxillary posterior region was examined. Seventy-five patients who underwent Le Fort I osteotomy without forward movement of the maxilla but with superior repositioning of the maxilla were included in this study. The bone volume around the descending palatine artery (DPA), the angle of the junction between the pterygoid process and the tuberosity, and the distance between the upper second molar and the pterygoid process were measured via three-dimensional analysis. A significant negative correlation (r = ?0.566) was found between the bone volume around the DPA and the ratio of repositioning (actual movement divided by expected movement). It is possible that the superior repositioning of the maxilla expected prior to surgery was not sufficiently attained because of the large volume of bone around the DPA. The results of this study show that in some patients, superior repositioning was not achieved at the expected level because of bone interference attributable to the anatomical form of the maxillary posterior region.     

Surgical effects of various orbital decompression methods in thyroid-associated orbitopathy: Computed tomography-based comparative analysis

ObjectivesTo evaluate the surgical effects of orbital fat decompression and bony decompression in each orbital wall using computed tomography (CT) in thyroid-associated orbitopathy (TAO).MethodsIn 27 TAO patients (48 orbits) with exophthalmos who underwent orbital wall decompression combined with fatty decompression, we recorded the resected orbital fat volume intraoperatively and estimated the decompression volume of the orbital wall in the deep lateral, medial and inferior walls using postoperative orbit CT images. Then, the correlation between exophthalmos reduction by Hertel reading and decompression volume in each area was analyzed to validate the surgical predictability, surgical efficiency and contribution level to total exophthalmos reduction.ResultsThe decompression volume in orbital fat and the deep lateral wall showed relatively high correlation with exophthalmos reduction (surgical predictability) compared to medial and inferior wall. The surgical efficiency was highest at deep lateral wall (2.704 ± 0.835 mm/cm³), followed by medial wall (0.892 ± 0.527 mm/cm³), orbital fat (0.638 ± 0.178 mm/cm³) and inferior wall (0.405 ± 0.996 mm/cm³). The actual contribution level to total exophthalmos reduction was highest in fatty decompression, followed by deep lateral decompression.ConclusionIn TAO patients with exophthalmos, orbital fat and deep lateral orbital wall are more predictable and contributory surgical targets for postsurgical exophthalmos reduction.     

Maxillary sinus augmentation using xenogenic bone substitute material Bio-Oss in combination with venous blood. A histologic and histomorphometric study in humans

The aim of the present study was to evaluate bone formation following maxillary sinus augmentation using bovine bone substitute material Bio‐Oss^® in combination with venous blood by means of histologic and histomorphometric examination of human biopsies. This involved a total of 15 sinus floor elevation procedures being carried out on 11 patients (average age of 49.6 years) according to the technique described by Tatum (1986). The subantral sinus cavity was augmented using bovine apatite combined with venous blood. After an average healing phase of 6.8 months, trephine burrs were used to take 22 bone biopsies from the augmented sinus region. Then 38 Brånemark^® implants were inserted in both the osteotomies resulting from bone sampling and in regular sites in the augmented posterior maxilla. Histomorphometric analysis of ground sections from the bone biopsies prepared according to the standard method of Donath & Breuner (1982) produced an average percentage of newly‐formed bone of 14.7% (±5.0%) and a proportion of residual xenogenic bone substitute material of 29.7% (±7.8%). Some 29.1% (±8.1%) of the surface of the Bio‐Oss^® granulate was in direct contact with newly‐formed bone. Histologically, newly‐developed bone became evident, partly invaginating the particles of apatite and forming bridges in the form of trabeculae between the individual Bio‐Oss^® particles. Despite the absence of osteoclastic activity, the inward growth of bone indicates slow resorption of the xenogenic bone graft material. When the implants were uncovered, after an average healing phase of 6 months, 4 of the 38 implants had become loose. Of these 4 implants, 1 had to be subsequently explanted, while the others remained as “sleeping implants” and were not included in the implants superstructure. Thus, the resulting clinical survival rate, prior to prosthetic loading, was 89.5%.     

Volumetric CBCT analysis of the palatine process of the anterior maxilla: a potential source for bone grafts

The aim of this research was to use cone-beam computerized tomography (CBCT) to analyze the available bone volume in the palatine process of the maxilla (PPM), which is a potential source of bone grafts. 20 CBCT scans were evaluated. From the most caudal axial slice of the PPM, the bony surface was calculated cranially up to the nasal floor. The predetermined thickness of each slice was 0.9 mm. A 2 mm safety margin was established considering the incisive canal and teeth 14–24. A ±0.1 mm error deviation was established for all calculations. By connecting these points and those defined at the posterior bone boundary, a surface was obtained. A three-dimensional (3D) image of the delimited zone was constructed and analyzed using 3D imaging software. The study comprised 6 women and 14 men (mean age 39.4 ± 11.5 years). Calculated bone volume averaged 2.41 ± 0.785 cm³. The palatine process of the maxilla contains a considerable bone volume (2.41 ± 0.785 cm³). This area should be regarded as a potential donor site for the regeneration of maxillary atrophic bones. Further investigation is required before these findings lead to routine clinical application.     

Isolierte Orbitabodenfrakturen

Background

The goal of this retrospective study was quantitative calculation of area and volume of isolated orbital floor fractures from computed tomography (CT) and correlation of these data with post-traumatic ophthalmologic findings.

Patients and methods

A total of 76 patients with isolated orbital floor fractures were evaluated radiologically and clinically. CT scanning was performed in coronal sections (1.5-mm to 3.0-mm slice thickness) with contiguous table feed. Orbital floor and fracture area as well as volume of displaced tissue were measured and calculated from the CT dataset. The relation of quantitative CT data to ophthalmologic findings (motility, diplopia, and globe position) was assessed statistically.

Results

Calculation of the CT dataset revealed a mean orbital floor area of 6.33±1.05 cm², a mean fracture area of 2.60±1.14 cm², and a mean volume of displaced tissue of 1.16±0.80 cm³. Volume of displaced tissue correlated significantly with ophthalmologic findings (p≤0.01). Fracture area correlated significantly with globe position (p≤0.01) and was less associated with diplopia and motility disturbances (p<0.10).

Conclusion

Efficient evaluation of two-dimensional CT data enables quantitative assessment of orbital floor fractures. Position and function of the globe are mainly affected by the volume of displaced periorbital tissue.     

Pedicled segmental rotation techniques for posterior mandible augmentation: a preliminary study

Rehabilitation of the atrophic posterior mandible is a challenge in dental practice. Conventional treatments include the segmental sandwich osteotomy or inlay bone grafting (IBG), onlay bone grafting (OBG), short implants, distraction osteogenesis, and inferior alveolar nerve transposition (IANT), each with its downsides. This case series is reported to introduce a modification of IBG – pedicled segmental rotation (PSR) for the reconstruction of co-existing vertical and horizontal defects in the posterior mandible. Ten healthy patients with vertical–horizontal defects (no vertical bone walls and basal bone width <5 mm) were included. Posterior mandibular defects were treated with PSR, PSR + IANT, or PSR + OBG. In PSR, a pedicle-preserved segment is up-fractured superiorly and then flipped 90° to a vertical position. The segment is then supported with inorganic bovine bone and autogenous bone particulates. Cone beam computed tomography was performed preoperatively and at the 4-month follow-up, in addition to clinical examinations. Soft tissue healing was uneventful. Radiomorphometric analysis showed a mean new bone volume of 647.79 ± 81.31 mm³ (ΔH = 7.13 mm), 836.99 ± 119.14 mm³ (ΔH = 7.8 mm), and 640.20 ± 50.13 mm³ (ΔH = 6.59) in the PSR, PSR + OBG, and PSR + IANT groups, respectively. The proposed PSR technique used in this case series showed promising results for vertical and horizontal augmentation of the atrophic posterior mandible before placement of dental implants.     

The effect of salivary contamination on fissure sealant—enamel bond strength

The effect of accidental salivary contamination on the retention of fissure sealants is investigated via in Vitro bond tests and scanning electron microscopy. The strength of the bond between sealant and saliva contaminated and washed enamel (168 ± 14 kg cm^?2) is not found to be significantly different from the bond strength to uncontaminated enamel (174 ± 17 kg cm^?2). Unwashed contaminated enamel gives significantly reduced bond strength (68 ± 11 kg cm^?2).     

Effect of the lateral wall valgisation in the treatment of patients with endocrine orbitopathy

Orbital decompression is an established procedure used to correct exophthalmos that results from excess orbital soft tissue. This study aimed to explore a new minimally-invasive technique that features three-dimensional planning and patient-specific implants for lateral valgisation (LAVA) of the orbital wall. We analysed the outcomes of this procedure in nine endocrine orbitopathy (EO) patients (32–65 years of age with a mean clinical activity score of 4.3) who underwent this procedure between 2021 and 2022, including seven patients diagnosed with dysthyroid optic neuropathy. The impact of LAVA and wall resection on orbital areas, volumes, Hertel values, visual acuity, and new-onset diplopia was determined. Among our results, we found that LAVA and resection of 18 orbital walls resulted in significant enlargement of the orbital volume from a preoperative mean of 30.8 ± 3.5 cm³ to a mean of 37.3 ± 5.8 cm³ postoperatively (mean difference, 6.2 ± 1.8 cm³; p < 0.001); this procedure also resulted in a significant reduction in the mean Hertel value, from 28.7 ± 1.9 mm to 20.0 ± 1.9 mm (mean difference, 8.7 ± 1.9 mm; p < 0.001). The procedure resulted in visual acuity declined in three patients (33.3 %) with reductions from 0.25 to 0.125, 0.8 to 0.125, and 1.2 to 0.7, respectively. No new diplopia occurred postoperatively, however, our study included five patients with preoperative diplopia that did not improve postoperatively and required additional surgical intervention. Similarly, four patients required supplemental eyelid surgery. In conclusion, our study suggests the effects of the LAVA with the partial floor resection seems to be effective, which provides a substantially improved outcome for patients undergoing surgical treatment of EO via the use of double navigation and piezosurgical methods.     

Ozonated oil effect for prevention of medication-related osteonecrosis of the jaw (MRONJ) in rats undergoing zoledronic acid therapy

Objectives

The aim of this study was to evaluate the preventive effect of ozonated oil on the development of MRONJ-like lesions at tooth extraction sites in rats submitted to zoledronic acid treatment.

Materials and methods

Twelve rats were divided into two groups. Each rat received an injection of zoledronic acid solution once a week for 5 weeks before having its upper first molar extracted. In group 1, the clotted socket was maintained, while in the group 2, the socket was treated with ozonated oil for 10 min/day during 3 days. After euthanasia, block resection was performed for histological analysis. Necrotic bone was defined as the area of the bone with empty osteocyte lacunae and vital bone as the area with osteocyte-occupied lacunae.

Results

There was no statistically significant difference between the groups in the average area of vital bone (p = 0.2248) and the average area of necrotic bone (p = 0.1208). However, the average area of vital bone in group 1 was smaller (24.1 ± 2.9 cells/cm²) than in group 2 (26.8 ± 4.2 cells/cm²), and the average area of necrotic bone in group 1 was higher (7.0 ± 2.5 cells/cm²) than in group 2 (4.0 ± 1.1 cells/cm²), indicating that ozonated oil may reduce the development of osteonecrosis.

Conclusions

Our findings suggest that ozonated oil might prevent MRONJ-like lesions at tooth extraction sites in rats submitted to a disease induction protocol. Further research should be conducted to confirm this hypothesis.

Clinical relevance

MRONJ has been reported as a complication of surgical dental procedures, and there are currently no predictable preventive therapies.