Comparison of the effects of different rapid maxillary expansion techniques on craniofacial structures: a finite element analysis study.

AIM: To compare the effects of three different maxillary expansion appliances with five different types of expansion modalities on stress distribution and displacement on the maxilla and its adjacent craniofacial structures using the finite element method (FEM). MATERIALS AND METHODS: Cone-beam computed tomography data of a patient with maxillary transverse deficiency were rendered into a three-dimensional model of craniomaxillary structures. The expansion appliances included tooth-borne, hybrid, and bone-borne expanders. Five different expansion modalities were applied to each expander [conventional Rapid Maxillary Expansion (RME) (type 1), midpalatal suture cortico-puncture-assisted RME (type 2), LeFort l cortico-puncture-assisted RME (type 3), surgically assisted RME (SARME) without pterygomaxillary junction (PMJ) separation (type 4), and SARME with bilateral PMJ separation (type 5)]. The numerical and visual data were analyzed. RESULTS: The highest amount of stress accumulation on teeth was found in the tooth-borne and hybrid groups. On the other hand, more stress concentration on the maxilla was observed in the bone-borne group. SARME cuts with PMJ separation increased total movement by reducing the stress on the midpalatal suture in all groups. While types 1, 2, and 3 were similar in terms of the amounts of displacement, types 4 and 5 increased the total amount of displacement in all groups. The total amounts of displacements from the highest value to the lowest value for the anterior and posterior maxilla were in the bone-borne, tooth-borne, and hybrid groups. CONCLUSIONS: SARME cuts were effective in reducing stress on the teeth, but the cortico-puncture application affected neither the stress values on the teeth nor the transverse displacement in the tooth-borne expanders. Surgical procedures such as SARME and corticotomy should be used with bone-borne devices to improve the outcomes of maxillary expansion procedures.

Evaluation of Sinus Pneumatization and Dental Implant Placement in Atrophic Maxillary Premolar and Molar Regions.

PURPOSE: This study aimed primarily to examine the relationship between maxillary sinus variations and dental implant placement in the atrophic maxillary premolar-molar region. Secondly, the preferences of experienced clinicians with regard to implant length in the bone and sinus were evaluated. MATERIALS AND METHODS: The data were collected from panoramic radiographs of patients who had undergone dental implant surgery in the posterior maxilla. Parameters such as sinus pneumatization level, sinus floor elevation operation type, and length of dental implants in the sinus and bone (in millimeters) were evaluated. Groups were created for the categories mild-moderate-medial pneumatization and severe-extreme-medial pneumatization, with the subgroups severe and extreme medial pneumatization for medial pneumatization and "5 to 10 mm" and "≤ 5 mm" for inferior pneumatization of the maxillary sinus. The distribution of the data was evaluated with the Shapiro-Wilk test, and the Mann-Whitney U test was used to evaluate the millimeter measurements made in the groups. RESULTS: The mean implant length in bone tissue was measured as 6.3 mm in the mild-moderate-medial pneumatization group and 5.4 mm in the severe-extreme-medial pneumatization group (P < .001), whereas the mean implant length in the sinus was 3.6 mm in the mild-moderate-medial pneumatization group and 3.9 mm in the severe-extreme-medial pneumatization group, respectively (P < .001). The mean implant length in the sinus was 3.0 mm in the 5 to 10 mm group and 5.1 mm in the ≤ 5 mm group (P < .001), whereas the mean implant length in bone was measured as 6.6 mm in the 5 to 10 mm group and 3.6 mm in the ≤ 5 mm group (P < .001). CONCLUSION: This was the first study in the literature in which classifications of inferior and medial pneumatization of the maxillary sinus were used for the same implants and their correlation was evaluated in the presence of sinus pneumatization. In this study, the mean implant length in the sinus was measured to be greater as sinus pneumatization progressed medially. Therefore, like inferior pneumatization, medial pneumatization may also have risks attributable to the need for internal or external sinus elevation operations in the atrophic maxilla, and this could be easily underestimated if CBCT is not used.

Comparison of the Stability of Sandblasted, Large-Grit, and Acid-Etched Treated Mini-Screws With Two Different Surface Roughness Values: A Histomorphometric Study.

PURPOSE: To evaluate the effects of 2 different surface roughness values produced by sandblasted, large-grit, and acid-etched treatments at different loading conditions on the stability of mini-screws. MATERIAL AND METHODS: A total of 56 mini-screws (Group 1; 28 with Ra value of 1 µm, Group 2; 28 with Ra value of 1.5 µm) were inserted into the tibia of fourteen New Zealand rabbits. Surface analysis was performed before the placement of the miniscrews using multi-technique characterization. The mini-screws were loaded with 500 grf after different healing times: unloaded, immediate, 4 and 8 weeks. Resonance frequency analyses were performed immediately after mini-screw placement and at the end of loading. Biomechanical and histomorphometric analyses were also performed at the end of the loading period. RESULTS: All mini-screws preserved their stability at the end of the loading period. However, the resonance frequency analyses showed higher implant stability quotient scores for 8-week group, unlike the immediate loading and unloaded groups (P < 0.05). According to the infinite focus microscopy results, prolongation of healing time resulted in a greater bone area on the loaded mini-screws in Group 2 (P < 0.05). Similarly, the histomorphometric analysis revealed higher bone-to-implant contact values in the 8-week group. There was no significant difference in the stability between the miniscrews with the Ra values of 1 and 1.5 µm. CONCLUSIONS: Sandblasted, large-grit, and acid-etched treated mini-screws showed significantly higher stability with healing time under heavy forces. Sandblasted, large-grit, and acid-etched treated mini-screws can be removed without fracture of the screw or the bone surfaces.

The evaluation of the effect of hypercalcemia in oral pathologies.

OBJECTIVE: Hypercalcemia is determined as an increase in the serum calcium level (above 10.5 mg/dL or ionized calcium is above 1.5 mmol/L). It was aimed to evaluate the effect of the increased serum calcium levels in dental panoramic radiographs with oral pathologies. MATERIALS & METHODS: The final sample number of the present study was determined as 143. 61 patients with hypercalcemic calcium levels were grouped in Hypercalcemia Group (HPEG) whereas 82 patients were grouped in Normal Group. (NG) Measurements were performed only on the panoramic radiographs. The evaluated parameters were cyst-tumor or granuloma existence, sinus pneumatization, stylohyoid ligament calcifications, lamina dura loss, bone loss existence, etc. Statistical tests were carried out at p < 0.05 significance level. RESULTS: The cyst-tumor formation (p = 0.03) and stylohyoid ligament calcification (p = 0.009) and increased radiopacity (p = 0.03) were significantly more common in NG than the HPEG group. Alveolar bone loss (p = 0.001) and periodontal defects (p = 0.01) were significantly more common in HPEG than the NG group. There was no significant relationship between other examined parameters. (p > 0.05) CONCLUSION: The serum calcium level revealed statistically significant outcomes and a close relationship with the pathologies occurring in the alveolar bone in the oral and maxillofacial region. However, it is highly recommended to include more patients in the newly planned studies and another bone-related biomarker should be evaluated simultaneously.

The efficiency of ozone therapy and low-level laser therapy in rat facial nerve injury.

PURPOSE: Comparison of low-level laser therapy (LLLT) and ozone therapy (OT) methods for the treatment of facial nerve injury (FNI) in rats, evaluated by histomorphometric measurement analysis. MATERIALS AND METHODS: Thirty rats were randomly divided into control (C), LLLT, and OT groups. The left facial nerves (FNs) of all rats (n = 30) were used in this study. These were held in a surgical clamp for 30 s to create neuropathic damage. The non-injured right FNs of the rats in the control group formed the fourth, sham (S) group in this study (n = 10). Therefore the total number of evaluated samples was 40. The injured FNs of rats in the control group were left to heal spontaneously, whereas LLLT was applied for 21 consecutive days (output 100 mW/cm2 and wavelength 850 nm) and OT (2 ml; 80 µm/ml) once every 2 days for 21 days. RESULTS: After histomorphological evaluation, the OT group revealed statistically significant outcomes following FNI compared with the OT and control groups in terms of branching of nerve fibers (p = 0.003), nerve fiber diameters (p = 0.0398), nerve fiber areas (p = 0.042), and axon numbers (p = 0.0327). Although the LLLT group revealed a better healing process than the control group, the outcome was not statistically significant in terms of branching of nerve fibers (p = 0.6804), nerve fiber diameters (p = 0.7424), nerve fiber areas (p = 0.7048), and axon numbers (p = 0.7588). CONCLUSIONS: OT resulted in statistically significant differences in outcome when compared with the LLLT and control groups, and provided a safe and effective treatment for FNI in rats. OT could therefore be considered as an alternative treatment of FNI. Clinical studies should now be performed to establish whether comparable results can be achieved in humans.

Histologic and Biomechanical Evaluation of Osseointegrated Miniscrew Implants Treated with Ozone Therapy and Photobiomodulation at Different Loading Times.

PURPOSE: The aim of this study was to evaluate how continuous heavy orthopedic forces affect the stability of sandblasted, large-grit, acid-etched (SLA)-surfaced miniscrew implants and surrounding bone tissue healing at three different loading periods with treatment of photobiomodulation and ozone therapy. MATERIALS AND METHODS: Miniscrew implants were applied on the tibias of 9-month-old rabbits (n = 18). The animals were randomly divided into three groups: control, photobiomodulation, and ozone therapy. In all groups, miniscrew implants were loaded with 500 gf at 0, 4, and 8 weeks, respectively (G1, G2, and G3). Several biomechanical and histologic analyses were performed in different centers to measure the implant stability quotient level, bone volume, and bone-to-implant contact. RESULTS: According to the results of the Infinite Focus Microscopy, the ozone therapy group revealed significantly higher scores than the control group and photobiomodulation group at the 4-week loading time, whereas the photobiomodulation and ozone therapy groups revealed significantly higher scores than the control group at the 8-week loading time in terms of bone volume measurements in mm3 (P < .05). According to the histologic analysis, the ozone therapy and photobiomodulation groups revealed significantly higher scores than the control group at the 4-week loading time, whereas the photobiomodulation group showed the highest scores among the 8-week loading groups (P < .05). CONCLUSION: This is the first study in the literature that reveals a better osseointegration process in miniscrew implants when treated with photobiomodulation and ozone therapy compared with control groups. Although the photobiomodulation and ozone therapy groups did not reveal significantly higher scores in immediately loaded miniscrew implants (G1), these treatments were significantly more effective when loaded after 4 or 8 weeks of osseointegration (G2 and G3). SLA-surfaced miniscrew implants are successful in the orthopedic forces (500 gf) and can be removed without complications.

Removal of a supernumerary tooth displaced into the infratemporal fossa during extraction.

Accidental displacement of an impacted tooth into the infratemporal fossa (ITF) is a rare but serious complication because of the vulnerability of the surrounding anatomical structures. Here we present the case of a 40-year-old man who reported pain on the right side of his face. Panoramic radiography and cone-beam computed tomography revealed an impacted third molar and a supernumerary tooth positioned immediately below it. Under local anesthesia, the third molar was easily extracted; however, the supernumerary tooth was inadvertently displaced into the ITF. The position of the tooth was confirmed by radiographic examination, and it was immediately removed intraorally by expanding the flap and carefully dissecting the soft tissues. Clinical aspects of this rare complication were evaluated, with special emphasis on the reliability of imaging modalities and surgical techniques.

Gastrointestinal tract metastasis of mandibular diffuse large B-cell lymphoma.

Not only diffuse large B-cell lymphoma is a malignancy, but also is initially and orally diagnosed in early stages. However, it could be misdiagnosed with other oral pathologies. However yet, early diagnosis is still crucial for the prognosis, morbidity, and mortality in such cases. Additionally, whole-body scanning with positron emission tomography/computed tomography should be performed for diagnosis and treatment process.

Spontaneous and Excellent Healing of Bilateral Brown Tumors in Mandible after Endocrinal Therapy and Subtotal Parathyroidectomy: Case Report with 4-Year Follow-Up.

Primary hyperparathyroidism is an endocrine disorder occurring due to increased secretion of parathormone resulting in a complex of clinical, anatomical, and biochemical alterations. On the other hand, excision of a parathyroid adenoma can normalize the metabolic status. A 24-year-old man was referred to the hospital with bilateral swelling and spontaneous gingival bleeding from posterior of the mandible also with radiolucent well-demarcated lesions bilaterally in the mandibular third molar regions. After consultations, the patient was hospitalized in the endocrinology department where further tests were performed due to highly increased PTH level as 714 pg/ml. Bilateral brown tumors started to regress spontaneously, and no additional surgery was required after subtotal parathyroidectomy was performed. The presented case is the first patient whose bilateral brown tumors in the jaws spontaneously and totally healed after subtotal parathyroidectomy and endocrinal therapy who was strictly followed up for 4 years even though the lesions were associated with impacted third molars.

Comparison of Ozone and Photo-Biomodulation Therapies on Mental Nerve Injury in Rats.

PURPOSE: This study compared photo-biomodulation (PBM) and ozone therapy (OT) for mental nerve injury by counting Schwann cells (SCs) and fasciculated nerve branches and measuring fascicular nerve areas. MATERIALS AND METHODS: The effects of OT and PBM on mental nerve injury were evaluated. Mental nerves of 27 rats were partly sutured and allocated into 3 groups. Group 1 received no treatment, group 2 received OT, and group 3 received PBM. The number of fascicules beyond nerve branches and the number of SCs before and after nerve injury were evaluated histologically. RESULTS: A better healing pattern was observed in the treatment groups. The number of SCs was markedly larger in the OT and PBM groups than in the control group. CONCLUSIONS: Oral and maxillofacial surgeons should be familiar with the differential diagnosis, prevention, and management of neurosensory disturbances. This study provides insights into the management of neurosensory disturbances related to mental nerve injury using OT and PBM. This study clearly suggests that OT and PBM are promising novel methods for the treatment of mental nerve injury.