Different Surgical Techniques in the All-on-4 Treatment Concept: Evaluation of the Stress Distribution Created in Implant and Peripheral Bone with Finite Element Analysis.

PURPOSE: To examine the stresses caused by different All-on-4 surgical techniques-conventional, a combination of monocortical and bicortical, bicortical, and nasal floor elevation-on the implant and the surrounding bone using 3D finite element analysis (FEA). MATERIALS AND METHODS: A 3D bone model of the atrophic maxilla was created based on CT imaging of the fully edentulous adult patient. All implants used in the models were 4 mm in diameter, and the length was 13 mm in the anterior and 15 mm in the posterior. Implants were applied to four different atrophic maxillary models with the All-on-4 technique: anterior and posterior monocortical implants in the first model, anterior monocortical and posterior bicortical in the second model, anterior and posterior bicortical in the third model, and anterior and posterior bicortical with nasal floor elevation in the fourth model. Eight linear analyses were performed by applying force from both vertical and 45-degree oblique directions to the four models prepared in our study. RESULTS: When the cortical and cancellous bone around the anterior implants was examined, it was observed that the oblique and vertical loading conditions and the stresses around the implant were similar in all models. When the posterior implants were examined, model 1 (ie, anterior and posterior monocortical implants) showed the greatest oblique compression, vertical compression, and vertical tension forces. According to the Von Mises stress (VMS) analysis results for anterior and posterior implants, higher values were observed in model 1 compared to models 3 and 4 under oblique and vertical forces. It was observed that bicortical placement of the implants reduced the stresses on the bone and implant-abutment system but had no significant effect on the stress on the bar. CONCLUSIONS: According to the results of our study, in the All-on-4 technique, bicortical placement of the implants reduced the stresses on the bone and implant when the anatomical limitations allowed. In addition, nasal floor elevation can be applied in the atrophic maxilla in appropriate indications.

Different Surgical Techniques in the All-on-4 Treatment Concept: Evaluation of the Stress Distribution Created in Implant and Peripheral Bone with Finite Element Analysis.

PURPOSE: To examine the stresses caused by different All-on-4 surgical techniques-conventional, a combination of monocortical and bicortical, bicortical, and nasal floor elevation-on the implant and the surrounding bone using 3D finite element analysis (FEA). MATERIALS AND METHODS: A 3D bone model of the atrophic maxilla was created based on CT imaging of the fully edentulous adult patient. All implants used in the models were 4 mm in diameter, and the length was 13 mm in the anterior and 15 mm in the posterior. Implants were applied to four different atrophic maxillary models with the All-on-4 technique: anterior and posterior monocortical implants in the first model, anterior monocortical and posterior bicortical in the second model, anterior and posterior bicortical in the third model, and anterior and posterior bicortical with nasal floor elevation in the fourth model. Eight linear analyses were performed by applying force from both vertical and 45-degree oblique directions to the four models prepared in our study. RESULTS: When the cortical and cancellous bone around the anterior implants was examined, it was observed that the oblique and vertical loading conditions and the stresses around the implant were similar in all models. When the posterior implants were examined, model 1 (ie, anterior and posterior monocortical implants) showed the greatest oblique compression, vertical compression, and vertical tension forces. According to the Von Mises stress (VMS) analysis results for anterior and posterior implants, higher values were observed in model 1 compared to models 3 and 4 under oblique and vertical forces. It was observed that bicortical placement of the implants reduced the stresses on the bone and implant-abutment system but had no significant effect on the stress on the bar. CONCLUSIONS: According to the results of our study, in the All-on-4 technique, bicortical placement of the implants reduced the stresses on the bone and implant when the anatomical limitations allowed. In addition, nasal floor elevation can be applied in the atrophic maxilla in appropriate indications.

How efficient are facial masks against COVID-19? Evaluating the mask use of various communities one year into the pandemic

Face masks are devices worn over the mouth and nose to protect against splashes, infectious respiratory droplets, or aerosols generated during breathing or coughing according to their filtering capacity. Medical masks, respirators, or cloth masks have been used for source control and for the protection of the exposed. After the first case on March 11, 2020, in Turkey, National COVID-19 Scientific Advisory Board published various contents for the correct use of masks. Medical face masks have been used in healthcare settings for both source control and potential personal protection before the COVID-19 pandemic. Adverse events associated with using masks are very sparse and mainly associated with tight-fitting respirators or dermatitis due to prolonged use and should not be a reason for refusal to use. Studies suggest the use of masks mainly in the healthcare facilities but also in the community for source control of people who have respiratory symptoms of communicable diseases other than COVID-19. They are likely to be acceptable if recommended, particularly in more severe epidemics and pandemics. Metaanalysis, case control, cross sectional, cohort, retrospective, retrospective cross sectional, research, randomized controlled, and controlled comparison studies were reviewed on the protective effect of masks on COVID-19 with laboratory evidence. Optimum use of face masks with additional precautions has been found to be useful controlling the spread of the respiratory viruses such as SARS-CoV-2 in most of the studies and metaanalyses. As a conclusion, the recent evidence in COVID-19 pandemic is consistent with the previous studies which have shown association between face mask use and decreased risk of viral infections, and medical face mask use should be encouraged both for the community and healthcare facilities along with other infection control measures such as hand hygiene, during outbreaks when there is widespread community transmission.

Long-Term Outcome of Arthrocentesis Plus Hyaluronic Acid Injection in Patients With Wilkes Stage II and III Temporomandibular Joint Internal Derangement.

OBJECTIVE: Arthrocentesis is a minimally invasive procedure used to manage temporomandibular joint (TMJ) internal derangement (ID). This study evaluated the outcome of arthrocentesis in patients with Wilkes stage II and III TMJ ID. PATIENTS AND METHODS: This retrospective study enrolled 50 patients who underwent arthrocentesis in 2011 and 2012 at the Karadeniz Technical University, Faculty of Dentistry, Department of Oral and Maxillofacial Surgery, Turkey. In total, 43 patients underwent unilateral arthrocentesis, whereas 7 patients had bilateral arthrocentesis. The clinical parameters recorded were pain (visual analogue scale [VAS] 0-100 mm during movement), chewing function efficacy (VAS 0-100), clicking sounds, and mandibular movements, including maximum interincisal opening (MIO), lateral excursion, and protrusion. All the parameters were recorded preoperatively, and 1, 3, 6, and 24 months after treatment. RESULTS: The MIO, lateral excursion, and protrusion were significantly greater than preoperatively in all the patients. Pain declined significantly postoperatively. The patients in Wilkes III group had greater improvement in mandibular movement and pain than the patients in Wilkes II group. CONCLUSION: Arthrocentesis was reliable for treating both Wilkes II and III TMJ ID, and the treatment results were better in Wilkes III patients.

Horizontal maxillary sinus septa: An uncommon entity.

INTRODUCTION: Maxillary sinus septas are barriers of cortical bone that arise from the floor or from the walls of sinus and may even divide the sinus into two or more cavities. Morphologically maxillary sinus septa are generally oriented in buccopalatinal orientation horizontal or sagittal orientation of the sinus septa is a rare condition. PRESENTATION OF CASE: This report presents two sinus lift case, in which observed septa in a horizontal orientation was presented. Both cases were fixed by an implant supported prosthethic restoration. DISCUSSION: Surgeons must know detailed knowledge about maxillary sinus anatomy for successful sinus augmentation. Computed tomography (CT) is useful for examining the maxillary sinus. CONCLUSION: Horizontal-type sinus septa are rarely seen. Surgeons must be aware of septa types and orientations.

Comparative treatment outcomes of menopausal and nonmenopausal women after arthrocentesis.

OBJECTIVES: Most of the patients treated for temporomandibular joint disorders constituted from the female population, and this situation is generally hypothesized and demonstrated in several studies. Arthrocentesis of the temporomandibular joint is a minimally invasive and effective treatment method in the management of patients with stage III and stage IV Wilkes syndrome. This study was aimed at assessing the effectiveness of this method between menopausal and nonmenopausal female patients. STUDY DESIGN: A total of 59 patients (25 menopausal and 34 nonmenopausal) were evaluated according to the visual analog scale for pain and chewing function scores, joint sound, and maximum mouth opening. RESULTS: In both groups, the parameters were detected statistically significant according to follow-up periods. The menopausal group showed better results than the nonmenopausal group at 6-month controls. CONCLUSION: In conclusion, arthrocentesis is a satisfactory treatment modality in the management of temporomandibular joint derangements. Female reproductive hormone levels may affect the success of this procedure.

Does an alkaline environment prevent the development of bisphosphonate-related osteonecrosis of the jaw? An experimental study in rats.

OBJECTIVE: To investigate the preventive effect of locally applied sodium bicarbonate on bisphosphonate-related osteonecrosis of the jaw (BRONJ). STUDY DESIGN: Thirty-six Sprague-Dawley rats were divided into 4 groups. Animals in group I received 0.1 mg/kg sterile saline 3 times per week for 8 weeks. Groups II, III, and IV received intraperitoneal zoledronate injection in the same manner with the same frequency and duration. The right first molar tooth was extracted in groups III and IV. One mL 8.4% sodium bicarbonate (SB) was applied to the extraction socket at the time of extraction in group IV. The effect of locally applied SB as an alkalizing agent was evaluated by histomorphometric analysis. RESULTS: BRONJ was observed in none of the animals in the control groups, 67% of the animals in the tooth extraction group, and none of the animals in the local SB application group (P < .01). CONCLUSIONS: Administration of locally applied SB had positive effects on the prevention of BRONJ in animals, but further studies are required to verify the effectiveness of this form of treatment before its use in humans.

Short-term results of prolotherapy in the management of temporomandibular joint dislocation.

OBJECTIVE: Prolotherapy, the rehabilitation of ligaments or tendons by induced proliferation of cells by using dextrose, is a noninvasive and effective method for the treatment of temporomandibular joint (TMJ) dislocation. The aim of this study was to evaluate the efficacy of prolotherapy method for the management of acute or chronic dislocation of TMJ. MATERIALS AND METHODS: In this study, 10 patients with TMJ dislocation (2 acute, 8 chronic) were examined retrospectively. All patients consisted of female patients, with a mean age of 28.4, who were treated with prolotherapy procedure. Differences of visual analog scale scores in quality of life, pain on function, and chewing function efficacy between sessions were investigated using the Wilcoxon t test and median values of sessions were evaluated using the Kruskal-Wallis H test. The amount of change at the maximum mouth opening occurring between the preoperative and postoperative values and the frequency of locking episodes were calculated, with results considered statistically significant at P < 0.05. RESULTS: Pain on function scores were significantly decreased in all patients, and TMJ locking were not observed during the follow-up period. Maximum mouth opening exhibited a tendency to decrease, but it was not statistically significant. Also, clicking sound on function presented no significant change (P > 0.05). On the other hand, the visual analog scale scores for quality of life showed significant improvement in all patients (P < 0.05). CONCLUSIONS: The results of this study show that prolotherapy can be used as an efficient, simple, and conservative method to treat TMJ dislocation.

An acoustical analysis of the effects of maxillary sinus augmentation on voice quality.

OBJECTIVE: Increased experience in sinus lifting procedures has led to a number of literature reports, but the potential effects of sinus lifting on voice quality is not clearly addressed in clinical studies. The aim of this study was to objectively investigate the effects of sinus lifting on alterations in voice quality and, in particular, on vocal resonance. STUDY DESIGN: A total of 17 patients who were in need of bilateral sinus augmentation were recruited. Acoustic analyses were performed before and after surgery. Volume changes in the sinuses were recorded before and after surgery using dental volumetric tomography. The Friedman test with Bonferroni correction was used to analyze the data. RESULTS: Changes in the perturbation parameters of acoustic sound analysis were found to be statistically significant. CONCLUSIONS: We recommend that all patients (especially voice professionals) be informed about the possible effects of sinus lifts on speech and voice alterations.

Marginal bone resorption around dental implants placed in grafted sinuses; an up-to-30-month clinical and radiological follow-up.

OBJECTIVE: To determine the relative success of two different bone grafting material - putty and powder forms of De-mineralised Bone Matrix (DBM) - used in sinus lift procedure. METHODS: The retrospective study was conducted at the Department of Oral and Maxillofacial Surgery, Ankara University, Ankara, Turkey, and comprised data related to the patients referred for bilateral maxillary sinus augmentation between 2007 and 2010. During the period, 48 endoosseous implants were placed concurrently with the sinus augmentation in 12 patients. Marginal bone loss around the implants was measured at the time of loading, 12 and 30 months after the treatment. SPSS 11.5 was used for data analysis. RESULTS: Of the 12 patients, 8 (66.6%) were females and 4 (33.3%) were males. All implants osseointegrated in both the putty and powder groups well without any significant clinical finding. The average volume of marginal bone resorption at implants for the putty side was 0.43 +/- 0.22 mm, 0.8 +/- 0.33 mm and 1.12 +/- 0.49 mm at prosthetic loading, 12-month and 30-month follow-up, respectively. For the powder side, the corresponding numbers were 0.48 +/- 0.32 mm, 0.82 +/- 0.46 mm and 1.24 +/- 0.57 mm. No statistically significant difference in bone loss between the two groups was observed (p > 0.05). CONCLUSION: Both putty and powder forms of de-mineralised Bone Matrix showed satisfactory results and there was no significant difference in marginal bone loss around dental implants and survival rates.

Evaluation of sedation in oral and maxillofacial surgery in ambulatory patients: failure and complications.

OBJECTIVES: This study evaluated the failure and complication rates of sedation in ambulatory patients undergoing oral and maxillofacial surgery. MATERIALS AND METHODS: This retrospective cohort study was carried out among 619 patients who had undergone maxillofacial surgical procedures under intravenous sedation with midazolam and fentanyl. Each patient's age, American Society of Anesthesiologists (ASA) classification, systemic condition, surgical procedure, complications, and failures were recorded for evaluation. RESULTS: A total of 400 patients with ASA I, 199 with ASA II, and 20 with ASA III between the ages of 9 months and 84 years were included in the study. The most common systemic disorders in our patients were mental retardation (35%), hypertension (19%), and epilepsy (15%). Evaluation of the cases revealed 9 complications (1.4%) and 9 sedation failures (1.4%). The complications were bradycardia, postoperative agitation and hallucination, drug reaction, vomiting and nausea, desaturation, and hypotension. CONCLUSIONS: Our results in the oral and maxillofacial surgery clinic revealed low complication and failure rates.

Comparative evaluation of antimicrobial effects of Er:YAG, diode, and CO2 lasers on titanium discs: an experimental study.

PURPOSE: This study examined carbon dioxide (CO(2); 10,600 nm), diode (808 nm), and erbium (Er):yttrium-aluminum-garnet (YAG; 2,940 nm) laser applications on Staphylococcus aureus contaminated, sandblasted, large-grit, acid-etched surface titanium discs and performed a comparative evaluation of the obtained bactericidal effects and the applicability of these effects in clinical practice. MATERIALS AND METHODS: This study was carried out in 5 main groups: Er:YAG laser in very short pulse (VSP) emission mode, Er:YAG laser in short pulse (SP) emission mode, diode laser with a 320-nm fiber optic diode laser with an R24-B handpiece, and CO(2) laser. After laser irradiation, dilutions were spread on sheep blood agar plates and, after an incubation period of 24 hours, colony-forming units were counted and compared with the control group, and the bactericidal activity was assessed in relation to the colony counts. RESULTS: The CO(2) laser eliminated 100% of the bacteria at 6 W, 20 Hz, and a 10-ms exposure time/pulse with a 10-second application period (0.8-mm spot size). The continuous-wave diode laser eliminated 97% of the bacteria at 1 W using a 10-second application with a 320-µm optic fiber, 100% of the bacteria were killed with a 1-W, 10-second continuous-wave application with an R14-B handpiece. The Er:YAG laser eliminated 100% of the bacteria at 90 mJ and 10 Hz using a 10-second application in a superpulse mode (300-ms exposure time/pulse). The Er:YAG laser also eliminated 99% to 100% of the bacteria in VSP mode at 90 mJ and 10 Hz with a 10-second application. CONCLUSIONS: The results of this study show that a complete, or near complete, elimination of surface bacteria on titanium surfaces can be accomplished in vitro using a CO(2), diode, or Er:YAG laser as long as appropriate parameters are used.

Radiologic evaluation of putty versus powder form of demineralized bone matrix in sinus floor elevation.

The aim of this study was to evaluate differences in ossification of the 2 forms of demineralized bone matrix (DBM)-putty and powder-radiographically, using digital densitometry on panoramic radiographs in maxillary sinus floor augmentation procedures. Twelve subjects needing bilateral maxillary sinus floor augmentation for the placement of osseointegrated implants were included in this study. The left and right maxillary sinuses were augmented in the same session in each patient using the 2 preferred forms of DBM-putty and powder-during the same session. One sinus was augmented with DBM putty form and the other sinus was augmented with DBM powder form randomly. Every patient had a total of 4 panoramic radiographs taken, preoperatively and in the first, third, and sixth month postoperatively. The densitometry measurements were taken from each step of the aluminium step-wedge, from both sinuses from different points a total of 3 times, and the average of these measurements was calculated. The amount of mineralization in each graft material in every radiograph was clarified by the appearance of a difference in the equivalent aluminium thickness, and the obtained results were statistically evaluated. The results showed that there were no significant differences between two graft materials statistically. These two graft materials could be good alternatives in sinus lifting procedures because of less morbidity, lower price, and good ossification. The results indicate that 2 different types of DBM achieved good ossification in the sinus lifting procedure, and there is not a considerable distinction in these 2 forms.

Tooth in the nose: unusual presentation of a misdiagnosed maxillary ossifying fibroma.

Fibro-osseous lesions involving the paranasal sinuses are uncommon, and making a determination of their histologic type is challenging. Correlating clinical and surgical findings with radiologic and histologic characteristics is essential for making a definitive diagnosis. We describe a case of misdiagnosed maxillary ossifying fibroma presenting as a solitary mass that completely filled and enlarged the left maxillary sinus. Another interesting finding was the presence of a molar tooth embedded in the tumor. We briefly comment on the genesis, natural course, and differential diagnosis of this lesion.

Methicillin-resistant Staphylococcus aureus (MRSA) osteomyelitis of the mandible.

Methicillin-resistant Staphylococcus aureus (MRSA) is a type of Staphylococcus that is resistant to certain antibiotics, such as methicillin, oxacillin, penicillin, and amoxicillin. This nosocomial pathogen has become a great threat in hospitals globally. Up to 40% of the normal population carries S. aureus in the anterior nares, and this rate is often higher in hospitalized patients and their attendants. This case report presents a patient with serious MRSA osteomyelitis of the mandible demonstrating purulent discharge. The patient failed to recover despite prolonged postoperative treatment and the administration of several antibiotics. There was a resulting nonunion along with chronic MRSA infection. The treatment protocol involved a multimodal approach with parenteral clindamycin infusion, local rifampicin irrigation, and intermaxillary fixation of the jaws.