Intraoral Splints Research Articles

Ventilatory and Perceived Ergogenic Effects of Mandibular Forward Repositioning During Running at Maximal Oxygen Uptake Intensity.

Cardoso, F, Costa, MJ, Colaço, P, Vilas-Boas, JP, Pinho, JC, Pyne, DB, and Fernandes, RJ. Ventilatory and perceived ergogenic effects of mandibular forward repositioning during running at maximal oxygen uptake intensity. J Strength Cond Res XX(X): 000-000, 2024-Wearing an intraoral dental splint may enhance ventilatory function and exercise performance. Nineteen runners performed on a 400-m outdoor track: (a) an incremental protocol to assess the velocity at maximal oxygen uptake (vV̇ o2 max) and (b) 2 square wave bouts wearing 2 intraoral splints (with and without mandibular forward repositioning). The time until exhaustion at vV̇ o2 max (TLimv V̇ o2 max), ventilatory variables, oxygen uptake (V̇ o2 ) kinetics, energetic profiling, perceived exertion and kinematics, were all measured. Ventilatory data were assessed breath-by-breath and perceived exertion evaluated using the Borg 6-20-point scale at the end of TLimv V̇ o2 max bouts. Images were recorded by video cameras (120 Hz) and kinematic measures retrieved using Kinovea. A paired t test was computed for comparison of splints ( p ≤ 0.05). With (vs. without) mandibular forward repositioning, runners increased their TLimv V̇ o2 max by ∼6% ( p = 0.03), coupled with higher ventilation (151 ± 22 vs. 147 ± 23 L·min -1 , p = 0.04), end-tidal oxygen tension (114.3 ± 3.7 vs. 112.9 ± 3.9 mm Hg, p = 0.003), and lower inspiratory time (0.526 ± 0.083 vs. 0.540 ± 0.090 seconds, p = 0.02), despite similar V̇ o2 kinetics (e.g., 49.0 ± 8.7 vs. 47.7 ± 8.6 ml∙kg∙min -1 of fast component amplitude) being observed. The energy expenditure was ∼8% higher ( p = 0.03) with the mandible forward, coupled with lower perceived exertion scores ( p = 0.04). Mandibular forward repositioning was effective in acutely improving running performance at vV̇ o2 max with ergogenic effects on ventilatory and perceived variables.

Changing the Mandibular Position in Rowing: A Brief Report of a World-Class Rower.

We investigated the acute biophysical responses of changing the mandibular position during a rowing incremental protocol. A World-class 37-year-old male rower performed two 7 × 3 min ergometer rowing trials, once with no intraoral splint (control) and the other with a mandibular forward repositioning splint (splint condition). Ventilatory, kinematics and body electromyography were evaluated and compared between trials (paired samples t-test, p ≤ 0.05). Under the splint condition, oxygen uptake was lower, particularly at higher exercise intensities (67.3 ± 2.3 vs. 70.9 ± 1.5 mL·kg-1·min-1), and ventilation increased during specific rowing protocol steps (1st-4th and 6th). Wearing the splint condition led to changes in rowing technique, including a slower rowing frequency ([18-30] vs. [19-32] cycles·min-1) and a longer propulsive movement ([1.58-1.52] vs. [1.56-1.50] m) than the control condition. The splint condition also had a faster propulsive phase and a prolonged recovery period than the control condition. The splint reduced peak and mean upper body muscle activation, contrasting with an increase in lower body muscle activity, and generated an energetic benefit by reducing exercise cost and increasing rowing economy compared to the control condition. Changing the mandibular position benefited a World-class rower, supporting the potential of wearing an intraoral splint in high-level sports, particularly in rowing.

Managing Long-term Orofacial Contractures and Microstomia Through Intraoral Stretching.

Microstomia and orofacial contractures continue to garner interest regarding the effectiveness of treatment methodologies utilized to impact functional change. Oral splints are an accepted tool in the management of microstomia. However, the concepts of which oral splints to use, timing of initiation, and duration of treatment have not gained a consensus. This article reviews approaches to oral splinting and an alternative intraoral approach using splints designed to provide a graded, low load, multidirectional, and prolonged stretch specifically in facial burn survivors including those with mature scars. Two participants participated in a trial using oral splints placed inside the mouth at established contracture points. Participants were requested to use the splints for 1h twice daily. Participants were photographed weekly producing 9 facial expressions, and distance between 13 facial landmarks was measured to evaluate change in tissue length. Numerical changes observed from beginning to end of the trial indicate positive and negative alterations, signifying lengthening or shortening of tissue. Negative changes denote reduction in distance between endpoints, while positive changes signify an increase. Participants verbalized functional improvements in oral motor and psychosocial function posttreatment. To date, oral splints can be custom fabricated for each individual patient. However, few oral splints are created to provide multidirectional stretch focusing on problem areas across the mid and lower face. The intraoral splints and regimen described here have the capability of providing a stretching intervention that could be applicable in various stages of burn recovery.

FEATURES OF THE TREATMENT OF HYPERMOBILITY OF THE ARTICULAR HEADS AND DISLOCATIONS OF THE LOWER JAW ON THE BACKGROUND OF FRACTURES OF THE CONDYGAL PROCESSES OF THE MANDIBLE, AS A PREVENTION OF ALLOPLASTIC REPLACEMENTS OF THE TEMPOMANDIBULAR JOINT

Acute, chronic, and recurrent dislocations are currently defined as conditions in which the mandibular process becomes dislocated from its joints and requires manipulation by another person to return to its normal position. Such conditions are usually preceded by either iatrogenic factors, including fractures of the mandibular branch, or joint instability and hypermobility of its heads. This pathology requires a personalized treatment algorithm: in each case, the clinical and radiological signs of this pathology should be clearly taken into account and the method of conservative or surgical treatment should be determined. Each of them has its advantages and disadvantages, and their combined use is also possible, which is the key to preventing more significant complications that can lead to allostatic replacements, joint components, or joint replacement as a whole.
 The purpose of the study is to conduct a comparative analysis of the data of clinical examinations, conservative and surgical treatment, complications and postoperative results, taking into account the prevalence of chronic dislocations of the mandible against the background of condylar fractures.
 Clinical cases of chronic dislocations of the mandible lasting from one to three months after osteosynthesis were analyzed by the authors. Attempts at manual reduction did not bring a positive result, so it was decided to treat the patients conservatively, using bite blocks made of self-hardening plastic and the use of elastic methods of fixation of the mandible, which gave a positive result already in the third week of treatment. Also, these patients were observed in the clinic for 6 months without visualization of complications of both mechanical and inflammatory nature.
 The analysis of clinical case data allows us to state that the goal of treatment should be to return the condyles to their original physiological position, and conservative methods should be in the first place when creating an algorithm. Early manual reduction of the joint heads is the best method of treatment, if it is possible to carry it out in a timely manner. As the duration of the dislocation increases, the joint cavity is filled with connective tissue, cartilaginous changes occur, adhesions between the articular surfaces are formed, the masticatory muscles shorten with possible fibrosis of the temporalis muscle. We have confirmed the fact that one of the best conservative treatments is the use of an elastic chin-parietal bandage, which acts as a fulcrum to move the heads back under the anterior slope of the articular tubercle, with the simultaneous use of arches and posterior occlusal rollers. If this treatment does not bring a positive result, we use intraoral splints with a fulcrum in the area of the second molar in combination with extraoral traction to move the heads in the posterior direction with simultaneous stretching of the capsule of the temporomandibular joint and its intracapsular ligaments.
 It should be noted that in each case, all the features of the pathogenesis of this disease should be taken into account and a personalized treatment algorithm should be developed, consisting of conservative methods, and, if ineffective, surgical treatment.

Drugs in dental biofilm and enamel – A pilot study

ObjectiveEnamel and dental biofilm might serve as alternative matrices for determination of illicit and medical drugs. Thus, this study aims at evaluating possible correlations between detected drug concentrations in the matrices and simulated drug use in situ. DesignEleven subjects wore intraoral splints with embedded demineralized bovine enamel samples. Drug use was simulated by mouth rinsing with a 1.0 μg/ml drug solution three times daily for 1 min (study A) or by incubation of the splints in a 10 μg/ml drug solution once a day for 30 min (study B). Amphetamines, opiates, cocaine and benzoylecgonine were used as drugs. After 11 days, biofilm and enamel samples of the intraoral splints were analyzed by liquid chromatography mass spectrometry after drying and extraction via ultrasonication with acetonitrile (biofilm) or methanol (enamel). ResultsIn study A, median and mean drug concentration ± standard deviation were 1.3 pg/mg and 6.4 ± 11 pg/mg in biofilm and 0.2 pg/mg and 0.5 ± 0.9 pg/mg in enamel. In study B, median and mean drug concentration ± standard deviation were 350 pg/mg and 1100 ± 1600 pg/mg in biofilm and 5.8 pg/mg and 9.9 ± 10 pg/mg in enamel. ConclusionsOverall, there were considerable interindividual concentration differences. Correlations between concentrations in the two sample materials were shown. The results of this pilot study revealed a dependence of concentrations on intensity and duration of drug contact. Thus, important information on past drug use might be provided in forensic cases by analysis of dental biofilm and enamel.

Effect of primary versus secondary splinting impression techniques on the passive fit of screw-retained implant prosthesis: a randomized clinical trial

BackgroundThe utilization of splinting techniques for impression copings is commonly advised for complex implant-supported prostheses, as it can enhance the fit of these prostheses. However, there is limited understanding regarding the impact of the secondary splinting of implant analogues, on the passive fit of the prostheses. Limited data are available on the secondary splinting of implant analogues before pouring the impression and its comparison with the primary technique of intraoral splinting of impression copings prior to impression making.ObjectivesThis study's objective was to determine the impact of the primary versus secondary impression splinting techniques using resin on the passive fit of screw-retained prosthesis.Material and methodsThis randomized clinical trial (RCT) involved two parallel groups consisting of 14 completely edentulous patients, with seven patients in each group. Each patient received a total of eight implants, four implants per arch, resulting in a total of 28 screw-retained prostheses. Two different impression splinting techniques were employed. Group (1) utilized the primary splinting technique, where the impression copings were splinted before taking the impression. In contrast, Group (2) utilized the secondary splinting technique, where the implant analogues were splinted before pouring the impression material. To evaluate the passivity of the screw-retained prostheses in both groups, a single-screw test (one-screw test) was used. Additionally, supplementary methods, including the screw resistance test, were employed.ResultsThe findings of this RCT revealed higher passivity scores for secondary splinting impression pouring technique with a statistically significant difference (P = 0.082). There was a 2.2-fold greater frequency of non-passivity in the primary splinted method. In group (2), the likelihood of non-passivity was four times higher for upper arches prostheses, while there was no significant difference (P = 0.5) observed in both groups for lower arches prostheses.ConclusionsThe study found that using the secondary splinting impression pouring technique resulted in greater passivity of the implant prostheses compared to the primary splinting impression technique.

A Novel Adjunct for Treatment of Orofacial Contractures After a Facial Burn Injury

Purpose: Surgical management of scar tissue and contractures from facial burns has systematic approaches, yet nonsurgical management continues to lack consensus regarding therapeutic approaches capable of providing stretching of the facial skin and muscles for both treating and preventing microstomia and orofacial contractures. This exploratory study introduces an intraoral splinting system designed to provide low-load, prolonged stretching of orofacial skin and musculature to treat contractures following a facial burn injury. The treatment adjunct described here has potential application across disciplines treating microstomia and orofacial contractures. Method: An 18-year-old man with full-thickness head and neck burns participated in a 5-week trial using intraoral splints to provide stretch to areas of contracture in the mid and lower face. The trial commenced 4 and a half months after his burn injury. Prescriptive placement, sizing, and time for use of the splints were provided. Changes in distance between facial landmarks were identified for 13 measurements taken for nine facial expressions. Results: Lengthening or shortening of the distances between two landmarks indicated the potential benefit from intraoral splints. For the expression “open mouth wide,” increased distance between two end points was noted in 11 of 13 measurements, ranging from 1.6 to 10.8 mm. This represents a lengthening of tissue, allowing for wider oral opening. Negative measurements between two end points occurred in two of 13 measurements, demonstrating elevation of the left and right nostrils. Visual data also demonstrated the appearance of change. Conclusions: When treating microstomia and orofacial contractures, consideration should be given to the use and further exploration of a more targeted intraoral methodology that uses a low-load, prolonged stretch to improve functional and aesthetic deficits. Oral splinting using an intraoral methodology is underutilized in the burn patient population and has application in both the acute care and chronic phases of recovery.

Biofilm formation on metal alloys and coatings, zirconia, and hydroxyapatite as implant materials in vivo.

Composition of implant material and its surface structure is decisive for oral biofilm accumulation. This study investigated biofilm formation on eight different materials. Eighteen healthy subjects wore intraoral splints fitted with two sets of eight materials for 24 h: zirconia [ZrO2 ]; silver-gold-palladium [AgAuPd]; titanium zirconium [TiZr]; Pagalinor [PA]; hydroxyapatite [HA]; silver-platinum [AgPt]; titanium aluminum niobium [TAN]; titanium grade4 [TiGr4]. Total biomass was stained by safranin to assess plaque accumulation while conventional culturing (CFU) was conducted to investigate viable parts of the biofilm. Cell viability of human gingival fibroblasts (HGF-1) was assessed in vitro. Statistical evaluation was performed with linear mixed-effects models to compare materials (geometric mean ratios, 95% CI), with the level of significance set at ɑ = .05. Less biofilm mass and CFU were found on noble metal alloys (AgPt, AgAuPd, and PA). Compared to AgPt, PA had 2.7-times higher biofilm mass value, AgAuPd was 3.9-times, TiGr4 was 4.1-times, TiZr was 5.9-times, TAN was 7.7-times, HA was 7.8-times, and ZrO2 was 9.1-times higher (each p < .001). Similarly, CFU data were significantly lower on AgPt, AgAuPd had 4.1-times higher CFU values, PA was 8.9-times, TiGr4 was 11.2-times, HA was 12.5-times, TiZr was 13.3-times, TAN was 16.9-times, and ZrO2 was 18.5-times higher (each p < .001). HGF-1 viability varied between 47 ± 24.5% (HA) and 94.4 ± 24.6% (PA). Noble alloys are considered as beneficial materials for the transmucosal part of oral implants, as less biofilm mass, lower bacterial counts, and greater cell viability were detected than on titanium- or zirconia-based materials.

Implementation of a Full Digital Workflow by 3D Printing Intraoral Splints Used in Dental Education: An Exploratory Observational Study with Respect to Students' Experiences.

Students were invited to provide feedback for their experiences with a training module that consisted of the following: intraoral scanning, computer-aided design (CAD), manual finishing, and insertion of a 3D-printed bite splint for the lower jaw. A total of 82 fourth-year students participated in the module. The average time required to perform an intraoral scan was 17 m 5 s, and all students were able to design a splint with an average time of 2 h 38 m. Students who indicated prior experience with CAD seem to outperform inexperienced students in both CAD task completion and intraoral scanning. The initial fit was reported as clinically acceptable by 68.5% of the participants, while 79% rated the workflow as very good to satisfactory and indicated that the training was helpful for dental practice. The implementation of a digital workflow in undergraduate dental education is feasible and has acceptable clinical results. However, CAD is time-intensive, and the experience can be challenging.

CLIKSS technique for Toronto Bridge with conometric coping technique and intraoral splinting with Dynamic Navigation

The aim of the technique is installing implants and providing fixed teeth with immediate loading thanks to digital design and the use of Navident. It foresees the use of fixtures with cone-morse prosthetic connection connected to conometric abutments of different heights with relative caps; the latter are activated by friction with the walls of the abutment which have a variable angle between 3 and 5 °. The implants are distributed along the entire arch seeking parallelism by limiting the cantilevers as much as possible (6-7 upper implants and 5-6 lower implants). The Navident helps a lot to have perfect parallelism between the implants. A silicone impression on the coupled in situ caps is taken at the end of the surgery, once the flaps have been sutured for the technician. The next day, the technician makes a DEFINITIVE Toronto Bridge prosthesis with Peek or other reinforced thermosetting resin technopolymer. The work is finished by filling the space between the cap and the prosthesis previously excavated by the technician with composite resin, closing the patient's teeth. There were 43 cases between upper jaws and lower jaws; 26 higher cases and 17 lower cases; No complications, 4 implant failures in upper jaws. CLIKSS technique provides intraoral passive fit, simple manufacturing and easy-removable prosthesis for the benefit of the patients

Effects of Wearing a 50% Lower Jaw Advancement Splint on Biophysical and Perceptual Responses at Low to Severe Running Intensities.

Acute ergogenic effects of wearing occlusal splints have been reported for aerobic and anaerobic exercises, but the literature centered on performance improvement by using jaw repositioning splints is scarce. We aimed to analyze the effect of wearing a 50% lower jaw advancement splint on biophysical and perceptual responses at low to severe running intensities. Sixteen middle- and long-distance runners performed twice a 7 × 800 m intermittent running protocol (with 1 km·h−1 increments and 30 s rest periods) in an outdoor track field using two lower intraoral splints (a placebo and a lower jaw advancer). These devices were custom manufactured for each participant and a randomized and repeated measure design was used to compare conditions. No differences between placebo and lower jaw advancer were found (e.g., 52.1 ± 9.9 vs. 53.9 ± 10.7 mL·kg−1·min−1 of oxygen uptake, 3.30 ± 0.44 vs. 3.29 ± 0.43 m of stride length and 16 ± 3 vs. 16 ± 2 Borg scores), but small effects were sometimes observed (e.g., 109.2 ± 22.5 vs. 112.7 ± 25.2 L·min−1 of ventilation, ES = −0.42). Therefore, this jaw advancement splint had no substantial ergogenic effect on biophysical and perceptual responses when running at different intensities.

Pathologic Mandibular Fracture Associated with Bilateral Dentigerous Cysts in a Dog

AbstractThis report describes the management and computed tomographic (CT) follow-up of a pathologic fracture of the mandibular body associated with bilateral dentigerous cysts in a 16-month-old Boxer. Bilateral, rostral, mandibular lesions consistent with dentigerous cysts were identified by intraoral radiography and CT. The left cyst was associated with an open, mildly displaced mandibular fracture. Treatment of the cystic lesions consisted of surgical exposure, extraction of embedded teeth, curettage of the cyst lining, and placement of demineralized bone matrix. Reduction and stabilization of the fracture were achieved by interdental wiring combined with an intraoral splint. Follow-up examination and CT imaging were performed at 8, 18, and 85 weeks postoperatively. Complete fracture healing and resolution of both cystic lesions were confirmed at 18 weeks with no recurrence evident at 85 weeks. No complications were encountered. To the authors' knowledge, this is the first case report of a pathologic mandibular fracture secondary to a dentigerous cyst in a dog, documenting the healing of dentigerous cysts via CT with progressive replacement of demineralized bone matrix by new osseous growth. Surgical treatment of the pathologic mandibular fracture and the bilateral dentigerous cysts resulted in an excellent clinical outcome.

Bonding Interface and Repairability of 3D-Printed Intraoral Splints: Shear Bond Strength to Current Polymers, with and without Ageing.

This in-vitro study investigates the bonding interfaces reached by the conditioning of a splint material additively manufactured by digital light processing (AM base) as well as the shear bond strength (SBS) of resins bonded to these surfaces (repair material). Therefore, the AM base was either stored in dry for 12 h or wet environment for 14 days to simulate ageing by intraoral wear. The dry and wet group was bonded after physical and/or chemical conditioning to cylinders made from polymethylmethacrylate or four novel polymers allowing splint modifications. Blasted and methylmethacrylate (MMA)-conditioned Polymethylmethacrylate (PMMA) bonded to PMMA acted as the gold standard. The surface profiles revealed highest differences of Ra towards the gold standard in AM base conditioned with other than MMA after sandblasting. The adhesively bonded repair materials of the wet AM base were further aged in wet environment for 14 days. The SBS of the gold standard (25.2 MPa and 25.6 MPa) was only reached by PMMA bonded to blasted and MMA-conditioned AM base after dry (22.7 MPa) and non-conditioned after wet storage (23 MPa). Four repair materials failed to reach the threshold of 5 MPa after dry storage and three after wet storage, respectively. Non-conditioned AM base revealed the highest risk for adhesive fractures when using other resins than PMMA.

Spacers with boluses applied to various sites of oral squamous cell carcinoma: Technical note and retrospective case series.

The present report describes a case series in which spacers with boluses were used at various sites in the oral cavity to enhance the therapeutic effect of radiation therapy in oral squamous cell carcinoma. In radiotherapy, the surface dose is reduced due to the build-up region of X-rays. In the present study, a bolus was used to complement the build-up region and increase the surface dose effect. A total of 7 patients with oral cancer from a primary care hospital underwent radiation therapy using spacers and added boluses to improve the surface dose effect. The spacer was made from a plastic splint and the bolus was connected to the splint with a quick self-curing resin. There were no complaints of pain or adverse events from the patients while wearing the intraoral splint. A total of 2 of the 7 patients were subsequently confirmed as having progressed disease, and the remaining 5 are currently being managed following a complete response to treatment. The spacers used at various sites of oral squamous cell carcinoma were safe and effective and did not cause any severe adverse effects.

Computer-Aided Design and Manufacture of Intraoral Splints: A Potential Role in Cleft Care

BackgroundNasoalveolar molding is a nonsurgical modality for the treatment of cleft lip and palate that uses an intraoral splint to align the palatal shelves. Repeated impressions are needed for splint modification, each carrying risk of airway obstruction. Computer-aided design and manufacturing (CAD/CAM) has the ability to simplify the process. As a precursor to CAD/CAM splint fabrication, a proof-of-concept study was conducted to compare three-dimensional splints printed from alginate impressions versus digital scans. We hypothesized that intraoral digital scanning would compare favorably to alginate impressions for palate registration and subsequent splint manufacture, with decreased production times. MethodsAlginate and digital impressions were taken from 25 healthy teenage volunteers. Digital impressions were performed with a commercially available intraoral scanner. Plaster casts made from alginate impressions were converted to Standard Triangle Language files. Patient-specific matched scans were evaluated for total surface area with the concordance correlation coefficient. Acrylic palatal splints were three-dimensionally printed from inverse digital molds. Subjective appliance fit was assessed using a five-point scale. ResultsA total of 23 participants were included. Most subjects preferred digital impression acquisition. Impression methods showed moderate agreement (concordance correlation coefficient 0.93). Subjects rated splints from digital impressions as having a more precise fit (4.4 versus 3.9). The digital approach decreased impression phase time by over 10-fold and overall production time by 28%. ConclusionsCAD/CAM has evolved extensively over the past two decades and is now commonplace in medicine. However, its utility in cleft patients has not been fully realized. This pilot study demonstrated that CAD/CAM technologies may prove useful in patients requiring intraoral splints.

Biofilm formation on metal alloys, zirconia and polyetherketoneketone as implant materials in vivo.

This study investigated biofilm formation on discs of metal alloys, zirconia and polyetherketoneketone in vivo. Sixteen healthy volunteers conducted two runs of 24hr each wearing an intraoral splint with 15 discs representing five different materials (gold-based [EL] and silver-based [PA] noble metal alloys; zirconia [ZR]; polyetherketoneketone [PEKK]; titanium zirconium alloy [TiZr]). Safranin staining assays and colony-forming unit (CFU) counts were conducted. Linear mixed-effects models were used to compare materials, and geometric mean ratios with 95% confidence interval were calculated with the level of significance set at α=0.05. Less biofilm mass and lower CFU counts were found on PA and EL, while ZR and PEKK developed similar levels as the reference material TiZr alloy. Compared with PA, biofilm mass was 1.5 times higher for EL (p=.004), 1.7 times higher for PEKK (p<.001), 2.2 times higher for TiZr (p<.001) and 2.4 times higher for ZR (p<.001). The culturing method confirmed these results for EL and PA with lower CFU compared to TiZr. The biomass staining technique and cell culturing correlated for EL and PA. Silver-based noble alloy and gold-based high noble alloy demonstrated the least biofilm formation indicating a potential clinical use as material for implant components in the transmucosal compartment. Zirconia and Polyetherketoneketone revealed similar results as the reference material titanium zirconium alloy used in commercially available titanium dental implant.

Adhesion of Hydroxyapatite Nanoparticles to Dental Materials under Oral Conditions

Hydroxyapatite nanoparticles (nano-HAP) are receiving considerable attention for dental applications, and their adhesion to enamel is well established. However, there are no reports concerning the effects of HAP on other dental materials, and most of the studies in this field are based on in vitro designs, neglecting the salivary pellicle-apatite interactions. Thus, this in situ pilot study aims to evaluate the effects of three hydroxyapatite-based solutions and their interactions with different dental material surfaces under oral conditions. Hence, two volunteers carried intraoral splints with mounted samples from enamel and from three dental materials: titanium, ceramics, and polymethyl-methacrylate (PMMA). Three HAP watery solutions (5%) were prepared with different shapes and sizes of nano-HAP (HAP I, HAP II, HAP III). After 3 min of pellicle formation, 10 ml rinse was performed during 30 sec. Rinsing with water served as control. Samples were accessed immediately after rinsing, 30 min and 2 h after rinsing. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to characterize the particles, and SEM evaluated the pellicle-HAP interactions. SEM and TEM results showed a high variation in the size range of the particles applied. A heterogeneous HAP layer was present after 2 h on enamel, titanium, ceramics, and PMMA surfaces under oral conditions. Bridge-like structures were visible between the nano-HAP and the pellicle formed on enamel, titanium, and PMMA surfaces. In conclusion, nano-HAP can adhere not only to enamel but also to artificial dental surfaces under oral conditions. The experiment showed that the acquired pellicle act as a bridge between the nano-HAP and the materials' surface.

Biomechanical comparison of locking compression plate fixation and a novel pedicle screw external fixation to repair equine mandibular fractures.

To determine the biomechanical properties of pedicle screw external fixation (PDW) for equine mandibular fracture repair and compare PDW to locking compression plates (LCP). Cadaveric study. Sixteen adult equine mandibles. Four mandibles were kept intact, while 12 were osteotomized and stabilized with the LCP or PDW construct (6 mandibles/group). Failure, stiffness, and yield were calculated from quasi-static ramp to failure and compared with previous analysis of mandibular fracture constructs. Tooth root involvement and method of failure were determined from radiographs and videos. Locking compression plate constructs achieved greater stiffness and load at failure (4656 ± 577 N-m/radian, 558 ± 27 N-m P < .05) compared with PDW constructs (2626 ± 127 N-m/radian, 315 ± 48 N-m). Yield did not differ between types of fixation (369 ± 57 N-m, 193 ± 35 N-m, P = .145). Tooth involvement was noted in two LCP constructs with failure via bone fracture. Pedicle screw external fixation constructs failed via wire unraveling and screw bending. Locking compression plate fixation increased stiffness and failure of constructs but did not influence yield. It also increased the risk to tooth root involvement relative to fixation with PDW. Compared with another study, PDW offered stiffness and failure similar to an intraoral splint with interdental wires, external fixator (EF), and external fixator with wires (EFW) and yield similar to an EF, an EFW, and a dynamic compression plate. Pedicle screw external fixation offers biomechanical stability comparable to other relevant mandibular fixation techniques and reduces the risk of tooth root damage compared with LCP fixation.

Construction of a gunning splint; Case report on the handling of mandibular fractures in edentulous patients

Establishing anatomic reduction of an edentulous mandible fracture is a frequently acknowledged challenge in craniomaxillofacial trauma surgery in elderly patients due to compromised medical condition, lack of occlusive dental surfaces to capitalize on maxillomandibular fixation and various contraindications for the surgical approach. The solution is to overcome such problems in an edentulous mandible is to create occlusal guidance by either making dentures or by fabricating intraoral splints to guide in the reduction of jaws in correct alignment. For such conditions, “Gunning splint” is a better option as it provides close reduction and stabilization of mandibular fracture. A case report is presented here where close collaboration between an oral surgeon and a prosthodontist comes into role. The oral surgeon, after assessing the exact nature and extent of fracture, must communicate with the prosthodontist regarding the type of splint and management of fracture for the improvement of the patient's prognosis.

A 3-year study of patients with tinnitus and jaw muscle tenderness

Objective: This study evaluated three-year results of treatment with an interocclusal appliance in 89 tinnitus patients with jaw muscle tenderness.Methods: Subjective tinnitus severity was recorded using a visual analog scale (VAS). The number of tender muscles was registered. The patients were followed annually. After three years, 64 patients were examined (72%).Results: Tinnitus severity at baseline was high (mean VAS value 68.3). After one year, the VAS values were substantially lower (mean 37.4; p < 0.001). During the following two years, there were no significant changes in VAS values. The mean number of tender muscles decreased from seven to two after one year and remained at this number for up to three years.Conclusion: In many tinnitus patients with signs of temporomandibular disorders (TMDs), intraoral splint therapy reduced tinnitus severity and jaw muscle symptoms. The favorable results after one year remained for up to three years without significant changes.