Intraoral Approach for Zygomaticomaxillary Complex and Orbital Floor Fracture With a Customized Ballooning Technique.

The zygomaticomaxillary complex and the orbital floor are commonly affected by mid-face fractures; their fractures pose challenges in reconstruction and can result in complications, such as enophthalmos. This study explores an intraoral approach with the help of a customized balloon technique and a contrast agent as an alternative to the conventional methods. A case report of a 67-year-old man with complex midfacial trauma is presented. The surgical process involved open reduction through an intraoral approach along with a transantral approach with the customized balloon technique. The procedure aimed to achieve reduction, fixation, and reconstruction of a complex mid-face fracture.

Quantitative light-induced fluorescence-guided surgery for medication-related osteomyelitis of the jaw.

BACKGROUND: Medication-related osteonecrosis of the jaw (MRONJ) is a challenging condition with increasing incidence, and the lack of clear surgical guidelines poses difficulties in its treatment. METHODS: Quantitative light-induced fluorescence (QLF), which can distinguish between vital and necrotic bone tissue without the need for additional markers, was used to guide minimally invasive surgery in a 75-year-old patient with MRONJ. RESULTS: This study demonstrated that QLF allows the real-time identification of infected and necrotic bone tissue during surgery, enabling precise and minimally invasive resection. We observed spontaneous bone recovery and remodeling in sclerotic bone areas that exhibited autofluorescence using a QLF device, suggesting its potential for preserving the bone tissue. CONCLUSION: This study highlights the promising application of QLF as a valuable photodiagnostic tool in MRONJ surgery, offering a noninvasive and intraoperative device for differentiating pathological bone tissue. This approach can potentially improve the precision of surgical interventions and contribute to improved patient outcomes in MRONJ management.

Rat Calvaria Model Mimicking the Intraoral Lesion of Medication-Related Osteonecrosis in the Jaw: A Preliminary Test.

Numerous preclinical intraoral models have been proposed to study medication-related osteonecrosis of the jaws (MRONJ). However, an extraoral animal model is necessary to investigate the effects of interventions such as grafts or direct therapeutics. This study aimed to establish a MRONJ rat model on the calvaria. Seven rats were allocated to either the control or MRONJ group. The MRONJ group received injections of zoledronic acid and dexamethasone to induce osteonecrosis over 4 weeks. Two weeks after these injections, the maxillary first molar was extracted, and two calvaria defects were created using a 4 mm trephine burr. One defect was left untreated, while the other was filled with harvested calvaria bone. A histological examination of all calvaria in the MRONJ group revealed avascular necrosis and the destruction of cortical bone. An independent t-test and Pearson's correlation coefficient were used for statistical analysis and the evaluation of alveolar and calvaria defects. The total alveolar and calvaria defect volume in the control group was significantly smaller than that in the MRONJ group. A statistically significant correlation was observed between alveolar and calvaria defects (Pearson correlation = 0.6, p = 0.023). The autogenous grafts showed poor results in the MRONJ group since they failed to revascularize and exhibited necrosis. The calvaria in this study successfully mimicked MRONJ lesions with avascular necrosis. This preclinical model could be used to develop treatments that are applicable to MRONJ.

Is conservative treatment (enucleation using modified Carnoy's solution) of odontogenic keratocyst in the maxilla good prognosis?

Odontogenic keratocysts (OKCs) located in the maxillae have rarely been reported in the literature. Standard treatment modalities for OKC range from marsupialization to marginal resection. However, most of the studies on OKC treatment have been related to mandibular OKCs. The anatomical structure and loose bone density of the maxillae and the empty space of the maxillary sinus could allow rapid growth of a lesion and the ability to tolerate tumor occupancy in the entire maxilla within a short period of time. Therefore, OKCs of the maxillae require more aggressive surgery, such as resection. As an alternative, this report introduces a modified Carnoy's solution, a strong acid, as an adjuvant chemotherapy after cyst enucleation. This report describes the clinical outcomes of enucleation using a modified Carnoy's solution in patients with large OKCs on the posterior maxillae. In three cases, application of a modified Carnoy's solution had few side effects or morbidity. Each patient was followed for four to six years, and none showed any signs of recurrence. In conclusion, adjuvant treatment with a modified Carnoy's solution can be considered a treatment option capable of reducing the recurrence rate of OKC in the maxillae.

Case series and technical report of nasal floor approach for mesiodens.

Objectives: This case series aims to introduce the nasal floor approach for extracting inverted mesiodens. Materials and Methods: Through a retrospective chart review between January 2022 and February 2023, we included the mesiodens patients using nasal floor approach, and analysis the location of mesiodens from the anterior nasal spine (ANS), total operation time, and complications. Results: Each mesiodens was located 10 to 12 mm from the ANS and was covered with a cortical layer of the nasal floor. All mesiodens were successfully extracted without exposing the adjacent incisors or nasopalatine nerve within 30 minutes from draping to postoperative dressing. Conclusion: The nasal floor approach is an efficient extraction method that reduces bone removal and prevents anatomical damage while removing the mesiodens just below the nasal floor bone.

Buccal nerve schwannoma mimicking a salivary gland tumor: a rare case report.

Schwannomas are benign tumors originating from myelinating cells constituting nerve sheaths but rarely contain cellular elements of the nerve. The authors encountered a 47-year-old female patient with a schwannoma on the anterior mandibular ramus arising from the buccal nerve, measuring 3 cm×4 cm. Surgical resection was performed with preservation of the buccal nerve via microsurgical dissection. After one month, the sensory function of the buccal nerve was recovered without complications.

Incorporating Moldable Demineralized Dentin Matrix into Treatment for a Jaw Cyst.

The enucleation procedure is a standard treatment for jaw cysts; however, it often results in post-operative bony defects. These defects can lead to serious complications such as the risk of pathologic fracture and delayed wound healing, especially in the case of large cysts where there may be soft tissue dehiscence. Even in the case of smaller cysts, most cystic defects remain visible on postoperative radiographs and can be mistaken for cyst recurrence during follow-up periods. To avoid such complications, the use of bone graft materials should be considered. While autogenous bone is the most ideal graft material as it can be regenerated into functional bone, it has limitations due to the inevitable harvesting surgery. Many tissue engineering studies have been conducted to develop substitutes for autogenous bone. One such material is moldable-demineralized dentin matrix (M-DDM), which can aid in regeneration in cases of cystic defects. This case report highlights a patient who demonstrated the efficacy of M-DDM in bone healing for filling the cystic defect.

Effect of a vertical incision on postoperative swelling after an impacted mandibular third molar extraction: two cases with split-mouth designed magnetic resonance imaging analysis.

This study examined the effects of a vertical incision on postoperative edema after third molar extraction. The study design was that of a comparative split-mouth approach. Evaluation was performed via magnetic resonance imaging (MRI). Two patients with homogeneous bilateral impacted mandibular third molars were enrolled. These patients underwent facial MRI within 24 hours after simultaneous extraction surgery. Modified triangular flap and enveloped flap incisions were made. Postoperative edema was evaluated by MRI and was assessed according to anatomical space. The two pairs of homogeneous extractions demonstrated that vertical incisions were associated qualitatively and quantitatively with extensive postoperative edema. The edema associated with these incisions spread toward the buccal space, beyond the buccinator muscle. In conclusion, a vertical incision with mandibular third molar extraction was related to edema in the buccal space and the fascial space, which contributed to clinical facial swelling.

A ramus cortical bone harvesting technique without bone marrow invasion.

Autogenous bone grafts from the mandibular ramus are a known source of inadequate bone volume scenarios of the residual alveolar ridge. However, the conventional block-type harvesting technique cannot prevent bone marrow invasion, which can cause postoperative complications such as pain, swelling, and inferior alveolar nerve injury. This study aims to suggest a complication-free harvesting technique and present the results of bone grafting and donor sites. One patient received two dental implants with a complication-free harvesting technique that involves creation of ditching holes with a 1 mm round bur. Sagittal, coronal, and axial osteotomies produced grid-type cortical squares using a micro-saw and a round bur to confirm the cortical thickness. The grid-type cortical bone was harvested from the occlusal aspect, and the harvesting was extended through an additional osteotomy on the exposed and remaining cortical bone to prevent bone marrow invasion. The patient did not suffer postoperative severe pain, swelling, or numbness. After 15 months, the harvested site exhibited new cortical bone lining, and the grafted area had healed to a cortico-cancellous complex with functional loading of the implants. Our technique, grid-type cortical bone harvesting without bone marrow invasion, allowed application of autogenous bone without bone marrow invasion to achieve acceptable bone healing of the dental implants and to regenerate the harvested cortical bone.

Effect of orbital volume in unilateral orbital fracture on indirect traumatic optic neuropathy.

PURPOSE: This retrospective study aimed to analyze the relationship between the volume of the fractured and the normal orbit in patients with unilateral orbital fractures with and without indirect traumatic optic neuropathy (TON). SUBJECTS: Data of 25 patients with unilateral orbital fractures who underwent computer tomography between January 2016 and December 2020 were investigated. Emergency imaging was performed within 2 hours of arrival at the emergency room. The subjects were categorized into two groups: unilateral orbital fractures with and without TON. METHODS AND MEASURES: The assessment of TON was performed during a comprehensive ophthalmologic examination by an ophthalmologist. The stereographic orbit was reconstructed, and the volume was calculated. Other variables examined included age, sex, and cause of orbital trauma. The variables were compared using paired t-tests. Statistical significance was set at p < 0.05. RESULTS: The orbital volume of the non-fractured orbit was 27.50 ± 2.26 and 27.48 ± 2.64 cm3 in the groups with and without TON, respectively. The average volume of the fractured orbit in the TON group was 27.78 ± 2.56 cm3, and there was no significant volumetric difference between the fractured and non-fractured sides in this group. However, the average volume of the fractured orbit without TON was 28.76 ± 3.18 cm3, larger than that of the non-fractured orbit (p = 0.016). CONCLUSIONS: Non-expansion of the fractured orbit was a risk factor for indirect TON in patients with unilateral orbital fractures. Volumetric analysis from primary imaging would expedite the diagnosis and treatment of TON, resulting in optimal outcomes.

Allogeneic Demineralized Dentin Matrix as rhBMP-2 Carrier: A Retrospective Clinical Study.

PURPOSE: To compare the clinical outcomes of autogenous and allogeneic demineralized dentin matrices loaded with recombinant human bone morphogenetic protein-2 (rhBMP-2; auto- and allo-DDM/rhBMP-2) by measuring the buccal marginal bone resorption around dental implants. MATERIALS AND METHODS: This retrospective study included patients who underwent dental implant placement with auto-DDM/rhBMP-2 as the control group and allo-DDM/rhBMP-2 as the experimental group. The primary outcome was buccal marginal bone resorption on CBCT. The resorption was calculated during T0 (from surgery to prosthetic loading), T1 (during the first year after loading), and T2 (during the second year after loading). The secondary outcome was the histologic analysis of five specimens of each group, obtained during the prosthetic procedure. RESULTS: Among the 103 implants, 61 and 42 implants were placed with auto- and allo-DDM/rhBMP-2 matrices, respectively. The resorptions of all periods were similar between the groups (T0: 0.65 ± 0.71 and 0.67 ± 0.81 mm, T1: 0.55 ± 0.60 and 0.59 ± 0.81 mm, and T2: 0.29 ± 0.45 and 0.20 ± 0.30 mm with auto- and allo-DDM/rhBMP-2, respectively). The histologic and histomorphometric analysis revealed similar osteoinductive aspects and proportions of new bone between the groups. CONCLUSION: Allo-DDM/rhBMP-2 showed comparable outcomes in terms of buccal marginal bone resorption to auto-DDM/rhBMP-2 during the second year after loading.

Sensory change after implant surgery: related factors for recovery.

Objectives: This retrospective study aimed to analyze data on nerve damage in patients who complained of sensory changes after dental implant surgery, the clinical results according to proximity of the implant fixture to the inferior alveolar nerve (IAN) canal, and the factors affecting recovery of sensation. Materials and Methods: The electronic medical records of 64 patients who had experienced sensory change after implant surgery were reviewed. Patients were classified by sex, age, implant installation sites, recovery rate and the distance between the implant fixture and IAN canal on computed tomography (CT). The distance was classified into Group I (D>2 mm), Group II (2 mm≥D>0 mm), and Group III (D≤0 mm). Results: The 64 patients were included and the mean age was 57.3±7.3 years. Among the 36 patients who visited our clinic more than two times, 21 patients (58.3%) reported improvement in sensation, 13 patients (36.1%) had no change in sensation, and 2 patients (5.6%) reported worsening sensation. In Group II, symptom improvement was achieved in all patients regardless of the removal of the implant fixture. In Group III, 8 patients (40.0%) had reported symptom improvement with removal of the implant fixture, and 2 patients (33.3%) of recovered patients showed improvement without removal. Removal of the implant fixture in Group III did not result in any significant difference in recovery (P=0.337), although there was a higher possibility of improvement in sensation in removal cases. Conclusion: Clinicians first should consider removing the fixture when it directly invades the IAN canal. However, in cases of sensory change after dental implant surgery where the drill or implant fixture did not invade the IAN canal, other indirect factors such as flap elevation and damage due to anesthesia should be considered as causes of sensory change. Removal of the implant should be considered with caution in these situations.

A rare case report of pseudomyopia after impacted teeth extraction under general anesthesia.

Ophthalmic complications after tooth extraction are rare but discomforting events. This paper reports the rare complications of a 20-year-old male patient who presented with transient blurring of vision after surgical extraction of several teeth under general anesthesia. Additional diagnostic tests were performed to discern the reason for the pseudomyopia. A literature review was carried out by searching for articles published from 1936 to 2019 using the keywords "dental," "ophthalmic," "complication," "blurring of vision," and "accommodation disturbance" in PubMed. Only six patients with detailed ophthalmic symptoms similar to those of our patient have been reported. If blurred vision or a myopic shift in refraction is present, pseudomyopia should be suspected, and cycloplegic refraction is essential for diagnosis. The condition improves spontaneously.

Volumetric analysis of spontaneous bone healing after jaw cyst enucleation.

The purpose of this study is to evaluate the degree of spontaneous bone healing after cyst enucleation as well as its contributing factors. Pre- and post-operative computed tomography (CT) scans of consecutive patients who had undergone jaw cyst enucleation were retrospectively analyzed. The outcome variable was healing ratio, which was calculated using the volume of the cyst before surgery and the volume of the defect in the bone after surgery. Predictor variables including duration of observation, pre-operative cyst size, age, gender, and involved jaw were analyzed to determine their influence. Forty-four subjects (30 Male and 14 Female, average 40.7 ± 15.7 years) were included in this study. Healing ratio was significantly lower during the first year (33.5 ± 32.8%) compared to the second (74.5 ± 24.2%) and subsequent years (74.2 ± 17.8%). In 35 patients who had follow-ups of over 1 year, the healing ratio was not affected by the pre-operative cyst size and upper/lower jaw except gender (p = 0.037, female > male) and age (p = 0.021, younger than 30 years > 30 years and older). The residual defect was significant larger in cysts 3 cc or larger (1.64 ± 1.54 cc) compared to smaller cysts (0.43 ± 0.42 cc, p = 0.006). The residual defect volume of large cysts was similar to those of the pre-operative volume of small cysts (1.47 ± 0.72 cc). In conclusion, spontaneous bone healing ratio of post-enucleation defects was about 73.5% after 12 months. Large cysts (> 3 cc) had larger defect, comparable to the volume of small cysts, but with altered contour. Additional treatment such as a bone graft may be considered especially in large cysts.

Needle orientation for temporomandibular joint arthrocentesis in Koreans.

OBJECTIVE: To investigate the highest opportunity skin puncture point and needle orientation according to facial asymmetry and classification. METHODS: Computed tomography of 136 patients was analyzed. Horizontal and vertical angles and distances from the canthal-tragal line were investigated to determine the puncture point and needle's angle. RESULT: All patients' average points were 7.39 (±2.85) mm anterior to the tragus and 3.44 (±4.18) mm below the canthal-tragal line with an angle of 8.53 (±6.90)° anteriorly and 32.26 (±7.23)° superiorly. Regarding asymmetry, there was a statistical difference in horizontal angle, depth, and canthal-tragal distance between the deviated and non-deviated sides. Especially, vertical distances were 4.44 (±4.66) mm and 2.59 (±4.11) mm in the deviated and non-deviated sides, respectively (p < 0.001). CONCLUSION: In closed-mouth, the puncture point was closer to the tragus and lower than the conventional point. The point in the deviated side should be considered lower than the non-deviated side.

The Effect of Whitlockite as an Osteoconductive Synthetic Bone Substitute Material in Animal Bony Defect Model.

This study aimed to evaluate the biomechanical properties in vitro and the bone regeneration of whitlockite (WH) compared with hydroxyapatite (HA) or ß-tricalcium phosphate (ß-TCP)-based material. We investigated the morphology and phase composition of the bone grafts using a scanning electron microscope and X-ray diffractometer patterns and tested the compressive strength. Four circular defects of 8 mm in diameter were created on the calvaria of twelve rabbits. One defect was left empty, and each of the other defects was filled with WH, HA, and ß-TCP. At 4 and 8 weeks, the specimens were harvested to evaluate for the new bone formation and the remaining bone grafts. Regarding the biomechanical properties, the three grafts had a similar micropore size, and WH showed nanopores. The compressive strength of WH was higher than HA and ß-TCP without statistical significance. The radiological and histomorphometric analyses demonstrated that the new bone formation was similar among the groups. The remaining bone graft of the WH group was greater than that of the HA and ß-TCP groups at 4 weeks (p < 0.05), and the total bone area of the WH, HA, and ß-TCP groups was greater than that of the other (p < 0.01). WH has excellent volumetric stability and osteoconductivity compared with HA and ß-TCP.

Effect of Gamma Irradiation on the Osteoinductivity of Demineralized Dentin Matrix for Allografts: A Preliminary Study.

Demineralized dentin matrix (DDM) treated with gamma irradiation (GR) has shown promising results as an allograft without any adverse effects in in vivo and clinical studies. The purpose of this study was to evaluate the effects of 15 and 25 kGy GR on the osteoinductive properties of DDM at extra-skeletal sites. As a control group, non-irradiated DDM powder was implanted into the right subcutaneous tissues of the dorsal thigh muscles of 20 nude mice. DDM powder irradiated with 15 and 25 kGy was implanted into the left side. After two and four weeks, the bone mineral density (BMD) was measured with dual-energy X-ray absorptiometry. After confirming osteoblast- and osteoclast-specific activities by alkaline phosphatase (ALP) and tartrate-resistant acid phosphatase (TRAP) staining, a histological analysis was performed to measure the new bone formation and the number of osteoblasts and osteoclast-like cells on the surface of the DDMs. Histomorphometry was used to calculate the new bone formation area on the surface of the DDM particles (DDMs). The BMD in all the groups increased from two and four weeks without statistically significant differences. The osteoblasts were dominantly activated on DDM without GR, and DDM treated with 25 kGy compared to DDM treated with 15 kGy. Among the groups, new bone formation was identified in all the groups at each time point. In conclusion, GR at doses of 15 and 25 kGy does not affect the osteoinductive properties of DDM powder.

Accuracy of dental implant placement with computer-guided surgery: a retrospective cohort study.

BACKGROUND: The aim of this study was to assess the accuracy of virtual planning of computer-guided surgery based on the actual outcomes of clinical dental implant placement. METHODS: This retrospective study enrolled patients among whom implant treatment was planned using computer-guided surgery with cone beam computed tomography (CBCT). The patients who received implant according to the guide with the flapless and flapped approach were classified as group 1 and 2, respectively, and the others who could not be placed according to the guide were allocated to the drop-out group. The accuracy of implant placement was evaluated with the superimposition of CBCT. RESULTS: We analyzed differences in the deviated distance of the entrance point and deviated angulation of the insertion of implant fixtures. With regard to the surgical approach, group 2 exhibited greater accuracy compared to group 1 in deviation distance (2.22 ± 0.88 and 3.18 ± 0.89 mm, respectively, P < 0.001) and angulation (4.27 ± 2.30 and 6.82 ± 2.71°, respectively, P = 0.001). The limitations of guided surgery were discussed while considering the findings from the drop-out group. CONCLUSIONS: Computer-guided surgery demonstrates greater accuracy in implant placement with the flapless approach. Further research should be conducted to enhance the availability of guides for cases with unfavorable residual bone conditions.

What Is the Perception of an Esthetic Lower Facial Third Profile in the Korean Layperson Population?

PURPOSE: The purpose of this study is to investigate whether there were differences in perception of facial profile esthetics at the upper lip, gnathic, and genial levels according to observer gender and age in the Korean layperson population. METHODS: Ten male (M1 to M10) and 10 female (F1 to F10) silhouettes with differing facial profiles at the level of the upper lip, mandibular, and chin were created from a male and female facial profile deemed well-balanced and orthognathic by reviewer consensus. These silhouettes were presented to 288 participants who were asked to rank the 5 most attractive male and female profiles. The participants were composed of 144 males and 144 females divided into 4 age groups: group I (under 20 years), group II (20 to 39 years), group III (40 to 59 years), and group IV (over 60 years). The most preferred profile and observer scores were investigated and calculated. Descriptive analysis, χ2 test, and analysis of variance were used for statistical analysis according to age and gender. RESULTS: The most preferred male and female silhouettes were orthognathic profiles. There was no significant difference according to gender when rating male (P = .281) and female (P = .442) silhouettes. No statistically significant difference was observed even when analyzed according to age groups. Although the difference in observer scores among each ranking showed a statistical difference according to age groups, the overall rankings showed a similar pattern both in male and female silhouettes. In the same age group, no difference in rank scores according to gender was observed. Severe concave profiles were found to have the lowest rank. CONCLUSIONS: An orthognathic profile was rated as the most desirable in the Korean layperson population, with few differences in perception of esthetic facial profile according to age and gender.

Follow-up evaluation of temporomandibular joints using magnetic resonance imaging after mandibular trauma: Case series analysis of young adult males.

BACKGROUND/AIMS: A relationship between mandibular fractures and traumatic temporomandibular joint (TMJ) conditions has been suggested in many studies. Although magnetic resonance imaging (MRI) is the best option for a TMJ evaluation, few studies have evaluated the TMJ condition after a mandibular fracture using MRI follow-up. The aim of this study was to evaluate the TMJ for post-traumatic conditions following a mandibular fracture using follow-up MRI. MATERIALS AND METHODS: Fourteen TMJs of seven young adult males (aged 19-21 years) with mandibular fractures were analyzed by MRI, and 12 TMJs of six patients were evaluated by follow-up MRI after the trauma. Regarding the intensity of MRI, the pathologic condition of TMJ was classified into acute joint inflammation, marrow edema, and joint space widening. RESULTS: Thirteen joints (92.9%) showed pathologic conditions, including 11 with acute joint inflammation (84.6%), 10 with joint space widening (76.9%), and six with marrow edema (46.2%). Five out of 12 evaluated joints were injected with dexamethasone. Among these, four joints healed within one week, and one healed within one month. Among the seven untreated TMJs, four and one joint healed within one week and one month, respectively, but two joints of one patient did not improve until one month. Although that patient received arthrocentesis, the right joint showed osteoarthritis six months after the trauma. CONCLUSIONS: Most TMJs were acutely damaged due to mandibular trauma and healed within one week to one month. A follow-up examination could be considered at one month after the injury to confirm the possibility of traumatic TMJ disorder, such as osteoarthritis.