Mouth Retractor Research Articles

Effect of the Teeth Whitening Procedure on the Mineral Composition of Oral Fluid.

The basis of modern tooth whitening systems is the use of a whitening gel, which usually contains hydrogen peroxide or carbamide peroxide. The study included 81 patients aged 22 to 35 years with a tooth color A2 and a darker color on the Vita Classic scale. The purpose of our research was to identify a new approach to whitening teeth to improve safety and gentleness. To perform this, we assessed the effect of the tooth whitening procedure on the mineral composition of the oral fluid. A new approach to the teeth whitening procedure was to use a mouth retractor and a tool for aspirating the whitening gel, which we developed. Before the procedure, a protective film-forming aerosol, which included sodium ascorbate, was applied. After the tooth whitening procedure, the enamel was remineralized with a sealing liquid for 14 days. The concentrations of calcium and phosphorus in the oral fluid were determined using a spectrophotometer with a set of reagents (Human). The results obtained indicate that the new approach to the teeth whitening procedure contributed to less pronounced changes in the concentrations of calcium (+29.07, p < 0.001) and phosphorus (-14%, p < 0.001) in the oral fluid immediately after the procedure and in combination with the standard procedure for teeth whitening; immediately after this procedure, the calcium concentration increased by 74.4% (p < 0.001), and the phosphorus concentration decreased by 23.07% (p < 0.001). The use of remineralizing agents led to a faster recovery of the initial levels of calcium and phosphorus in the oral fluid.

Boomerang Technique, The Buccal Mucosal Grafting Harvesting Model for Long Urethral Stricture Urethroplasty; A Case Series.

Currently, three methods are implicated in cases of long urethral stricture including harvesting buccal mucosa of inner cheeks, harvesting lip mucosa and finally lingual mucosal graft. This study evaluated the feasibility, safety and morbidity of our "Boomerang shape" technique used for graft retrieval from the inner cheeks to repair long urethral defect cases which are usually 12-15 cm in length and 2.5 cm in width. The Kilner-Doughty mouth retractor is inserted to give access to the donor site. Initially, the internal surface of the right/left cheek is cleaned with a solution containing 10% povidone-iodine. Then, Stensen's duct, located at the level of the second molar is identified and the desired size of the graft is measured and marked in a boomerang shape, 1.5 cm from the Stensen's duct and 1.5 cm from the edge of the cheek. To decrease submucosal bleeding from the harvest site, 1% lidocaine combined with a 1:100,000 epinephrine solution is injected using a 25-gauge long needle. The outlines of the graft are drawn by using a scalpel through the mucosa. Then, the outlined graft is sharply dissected and removed, leaving the muscle intact. A 5-0 polyglactin continuous suture is used for the closure of the harvest site. The standard graft harvested from the cheek should be 12-15 cm in length and 2.5 cm in width. Between 2017-2019, five adults have had their mucosal grafts harvested by the "Boomerang shape" technique in our center. No donor site complications were observed. Moreover, no urethral strictures or diverticulum occurred and the functional outcomes were satisfactory in all patients. Our routine technique of harvesting the buccal mucosa from the cheek is secure and easily performable by any surgeon. It has minimal incidence of intra and post-operative complications.

Assessing Performance in Simulated Cleft Palate Repair Using a Novel Video Recording Setup.

To test the feasibility of implementing a high-fidelity cleft palate simulator during a workshop in Santiago, Chile, using a novel video endoscope to assess technical performance. Sixteen cleft surgeons from South America participated in a 2-day cleft training workshop. All 16 participants performed a simulated repair, and 13 of them performed a second simulated repair. The repairs were recorded using a low-cost video camera and a newly designed camera mouth retractor attachment. Twenty-nine videos were assessed by 3 cleft surgeons using a previously developed cleft palate objective structured assessment of technical skill (CLOSATS with embedded overall score assessment) and global rating scale. The reliability of the ratings and technical performance in relation to minimum acceptable scores and previous experience was assessed. The video setup provided acceptable recording quality for the purpose of assessment. Average intraclass correlation coefficient for the CLOSATS, global, and overall performance score was 0.69, 0.75, and 0.82, respectively. None of the novice surgeons passed the CLOSATS and global score for both sessions. One participant in the intermediate group, and 2 participants in the advanced group passed the CLOSATS and global score for both sessions. There were highly experienced participants who failed to pass the CLOSATS and global score for both sessions. The cleft palate simulator can be practically implemented with video-recording capability to assess performance in cleft palate repair. This technology may be of assistance in assessing surgical competence in cleft palate repair.

Unintentional RF Energy Transfer During Tonsillectomy: An In Vitro Investigation

One-third of tonsillectomy patients experience post-operative taste disturbances (dysgeusia), yet the underlying cause is unknown. We hypothesize that unwanted radio-frequency (RF) energy couples to the metal-based mouth retractor during tonsillectomy and could be a possible cause of dysgeusia. To validate our hypothesis, in vitro studies are performed in a ground beef phantom with sensors measuring, first, the unwanted current coupled to the mouth retractor and, second, the unwanted temperature rise in the tissues that surround the retractor. The simulated surgery was performed using two separate surgical techniques: monopolar electrosurgery and coblation. Results indicate that unintentional RF energy transfer is indeed a real issue. During electrosurgery, peak-to-peak unwanted currents vary from 80.53 to 181.48 mA for typical power levels ranging from 10 to 30 W. Tissue temperature unintentionally increases by 1.3 °C and 1.8 °C, respectively. Coblation indicates smaller coupling effects, with peak-to-peak currents on the mouth retractor capped at 12.33 mA for a typical 7 W setting. Concurrently, tissue temperature is reduced by 0.73 °C, as attributed to the saline solution inherent to coblation. As the first of its kind, this study illuminates possible causes of post-tonsillectomy dysgeusia and intends to trigger future studies. The ultimate goal is safe and complication-free tonsillectomies.

Outcomes of staged lingual mucosal graft urethroplasty for redo hypospadias repair

The objective of this study was to present the outcomes for redo hypospadias repair using lingual mucosal graft (LMG). Between June 2012 and February 2017, 47 patients underwent staged LMG urethroplasty for redo hypospadias repair. The inclusion criteria were previous failed hypospadias repair with a paucity of local skin that interferes with correction using skin flaps and demands graft urethroplasty. During the first stage, a well-vascularized bed on the tunica albuginea was created. Then, the harvested LMG was secured to the prepared bed. The second-stage urethroplasty was carried out after six months. In this stage, tubularization of the previously implanted LMG was performed. In four cases, tubularization was difficult owing to graft contracture. This difficulty was managed by using the dorsally degloved penile skin as the onlay island flap in three cases and the buccal mucosa onlay graft in the fourth case. In all cases, a second protective layer from the dartos or tunica vaginalis was developed to cover the neourethra. The median (interquartile range [IQR]) age of patients at the first stage was 5 (4-6) years, and the median (IQR) duration between both stages was 7 (6-8) months. The median (IQR) follow-up after the second stage was 15 (13-16) months. The median (IQR) number of previous operations was 2 (2-3). The median (IQR) length of the LMG was 3 (2.5-4) cm, and the median (IQR) width was 1 (1-2) cm. No donor-site major complications, but mild oral discomfort in the first week after graft harvesting, were reported in 39 (83%) patients. After the second stage, complications were reported in nine (19.2%) patients, meatal stenosis in five and fistula in four. The reported success rate was 80.9%. Reconstruction of previously failed hypospadias is a challenge owing to local tissue scarring and a paucity of adjacent healthy tissue. In this study, the LMG was used in two-stage redo hypospadias repair after previous repair failure. In the present study, a success rate of 80.9% was reported after the second stage. According to this study and the published series, harvesting the LMG is associated with minimal immediate donor-site complications and no long-term morbidity. Another advantage of the LMG is easy harvesting with effortlessly reachable tongue in comparison with the buccal mucosa that is deep and requires application of a mouth retractor. Two-stage LMG urethroplasty is a reliable procedure for salvage urethroplasty. Lingual mucosal graft harvesting is easy, with minor oral complications.

Intraoperative image guidance in transoral robotic surgery: A pilot study.

Intraoperative image guidance during transoral robotic surgery (TORS) is hampered by imaging-friendly instrumentation and intraoperative positioning. The purpose of this study was to develop and validate an accurate image-guidance system for TORS. A custom radiolucent mouth retractor was fabricated from biocompatible material (Med-610; Stratasys, Minneapolis, MN). Teflon beads were placed in the oropharynx and carotid arteries of 3 cadavers. CT scans were obtained in the preoperative and intraoperative positions. Displacement of targets between preoperative and intraoperative scans was measured. Surgical navigation was based on the open-source Image-Guided Surgery Toolkit. Target registration error (TRE) was determined by measuring the distance between the tracker and bead registered to preoperative versus intraoperative scans. The inferior oropharyngeal targets demonstrated the greatest displacement between positions. A significant reduction in TRE was observed when registering the tracker to the intraoperative compared to the preoperative scan. This study describes an accurate intraoperative image-guidance system for TORS.

Intraoperative Image Guidance in Transoral Robotic Surgery – A Pilot Study

Background Intraoperative image guidance during transoral robotic surgery (TORS) is hampered by imaging-friendly instrumentation and intraoperative positioning. The purpose of this study was to develop and validate an accurate image-guidance system for TORS. Methods A custom radiolucent mouth retractor was fabricated from biocompatible material (Med-610; Stratasys, Minneapolis, MN). Teflon beads were placed in the oropharynx and carotid arteries of 3 cadavers. CT scans were obtained in the preoperative and intraoperative positions. Displacement of targets between preoperative and intraoperative scans was measured. Surgical navigation was based on the open-source Image-Guided Surgery Toolkit. Target registration error (TRE) was determined by measuring the distance between the tracker and bead registered to preoperative versus intraoperative scans. Results The inferior oropharyngeal targets demonstrated the greatest displacement between positions. A significant reduction in TRE was observed when registering the tracker to the intraoperative compared to the preoperative scan. Conclusion This study describes an accurate intraoperative image-guidance system for TORS.

Intraoperative image-guided transoral robotic surgery: pre-clinical studies.

Adequate resection of oropharyngeal neoplasms with transoral robotic surgery (TORS) poses multiple challenges, including difficulty with access, inability to palpate the tumor, loss of landmarks, and intraoperative patient positioning with mouth retractor and tongue extended creating significant tissue distortion from preoperative imaging. This study evaluates a workflow integrating intraoperative cone beam computed tomography (CBCT) for image-guided TORS through robotic experimentation locating 8-10 embedded targets in five porcine tongues and a cadaveric head phantom, conducted under various modes of visualization and integration of preoperative/intraoperative imaging. A statistically significant improvement in mean target localization error was achieved for both the porcine tongue ((9.8 ± 4.0) mm vs. (5.3 ± 1.3) mm, P-value = 0.0151) and cadaver ((11.2 ± 5.0) mm vs. (5.8 ± 2.5) mm P-value = 0.0189) in experiments comparing scenarios simulating current standard-of-care practice and the proposed image guidance system. Intraoperative image guidance with augmentation of critical surgical structures has the potential to improve target localization for TORS.

18-Gauge Needle Cap as Adjunct to Prevent Kinking of Endotracheal Tube

A self-retaining Dingman mouth retractor is widely used to keep the mouth open during cleft palate and intraoral surgery. The airway is at risk of being crushed or occluded as the gag (tongue plate) of the Dingman mouth retractor is being pushed against the endotracheal tube.Kinking of the endotracheal tube between the teeth and Dingman mouth retractor has been reported even with the oral Ring-Adair-Elwyn or flexometallic or armored endotracheal tubes. To minimize kinking of the endotracheal tube and its consequent complications, we routinely insert an 18-gauge needle cap at the potential space between the teeth and the tongue plate (gag) of the Dingman mouth retractor, which is situated lateral to the endotracheal tube. In our experience of approximately 5000 intraoral cases using a Dingman mouth retractor and 18-gauge needle cap, we have not had any tooth avulsion or aspiration of the 18-gauge foreign body while maintaining a consistent and secured airway during cleft palate and intraoral surgery.

Who Needs the Surgical Headlight?

The use of surgical headlights may lead to awkward posture and limit the mobility and visibility of the operating team. Despite the vast availability of fiber-optic instruments, many surgeons continue to use the surgical headlight, which may be harmful to their health and career. We report the use of the Lumitex LightMat surgical illuminator instead of the conventional surgical headlight in cleft palate surgery. The LightMat is a disposable single-use device that is bright, flexible, and malleable and attaches easily to most retractors. Twenty cleft palate and five pharyngeal flaps cases were performed in which the LightMat was attached to the Dingman mouth retractor with biocompatible two-sided adhesive tapes. The LightMat was successfully used in all 25 cases. No cases required the surgeon to put on additional lighting such as a headlight. In addition, no cases required the LightMat surgical illuminator to be replaced. The LightMat provides excellent surgical light for cleft palate surgery and pharyngeal procedures. It affords the surgeon several advantages: it provides a cool operative light, flexibility in surgical position, and improved visibility and mobility; the surgeon avoids the delay in obtaining an appropriate working headlight; and, more importantly, it may prevent postural problems that could lead to spinal sprain and disability.

Transoral operations for craniospinal malformations.

The transoral approach to the lower third of the clivus and to the ventral aspect of the upper cervical spine is used in craniospinal malformations with or without dislocation as well as in basilar aneurysms, ventrally situated cranio-spinal tumours, fractures of the odontoid process, and in rheumatoid arthritis compressing the spinal cord. In consideration of the literature and ten personal cases the indications and techniques of the transoral approach in craniospinal malformations are discussed. According to our own experiences and those of other authors it is possible to expose the lower clivus and the cervical spine down to C2 by a midline incision of the pharyngeal wall using a mouth retractor and oral intubation. Splitting of the soft palate or resection of the hard palate are not necessary, a tracheotomy should be performed only in exceptional cases. In congenital craniospinal malformations without dislocation or instability causing a ventral compression of the spinal cord, for instance by the odontoid process, the transoral decompression is preferable to dorsal decompressing operations. In cases of pure instability without any space-occupying lesion the transoral and posterior approach are possible in order to perform a fusion. The last one seems more advantageous in these cases. In craniospinal malformations with dislocation causing a ventral and dorsal narrowing of the spinal canal, apart from the decompression a stabilization has to be achieved. In these usually complex malformations individual treatment is necessary. According to the rare cases in the literature and to our own experience a primary anterior decompression, followed by a most careful posterior stabilization seems to produce the most favourable results.