Detachable Palatal Ramp of Teeth to Improve Comfort in a Completely Edentulous Patient with a Segmentally Resected Mandible.

The rehabilitation of a completely edentulous patient with segmental resection of the mandible (without osseous reconstruction) poses a considerable challenge to the restoring prosthodontist. Due to the absence of natural teeth in both arches, it is difficult to correct the mandibular deviation with the aid of guidance prostheses. Prosthetic management of such patients usually consists of a maxillary complete denture and mandibular segmental denture occluding in the deviated position itself. An additional ramp or row of denture teeth is placed on the palatal surface of the maxillary denture to facilitate this; however, patient comfort levels (during functions such as phonation) are found to be adversely impacted due to the encroachment of the tongue space by the position of the ramp. This report describes an innovative technique to overcome this problem by fabrication of a detachable ramp of additional denture teeth in the maxillary denture. The patient could wear the denture comfortably without the palatal ramp throughout the day and could attach the palatal ramp while eating.

Correction of deviation of a partially resected mandible using a palatal ramp with the aid of a semi-adjustable articulator.

Patients having undergone hemi-mandibulectomy without further reconstruction (to restore the lost mandibular continuity) suffer functional limitations due to the resultant deviation of the segmental mandible. A palatally based guidance prosthesis (or palatal ramp prosthesis) is often indicated and is usually fabricated chairside in self-cured acrylic resin. Establishing the correct angulation of the slope of the palatal ramp may take several attempts before a satisfactory correction is achieved. This clinical report describes a laboratory technique in which a semi-adjustable articulator was used for fabricating the palatal ramp prosthesis. The patient's deviated mandibular position was transferred to the articulator by means of a facebow and interocclusal record. The angulation of the palatal ramp was then established on the semi-adjustable articulator and the prosthesis fabricated in heat-cured acrylic resin. Reduced chairside time, improved patient comfort levels, and ease in fabrication of the prosthesis on the semi-adjustable articulator are proposed advantages of the described technique.

Effect of addition of titanium dioxide nanoparticles on the antimicrobial properties, surface roughness and surface hardness of polymethyl methacrylate: A Systematic Review.

Background: Polymethyl Methacrylate (PMMA) denture-base resins have poor surface properties that facilitates microbial adhesion causing denture stomatitis. This systematic review aims to evaluate the effect of different sizes and percentages of titanium dioxide nanoparticles (TiO2NP) on the antimicrobial property, surface roughness and surface hardness of PMMA denture base resin.  Methods: A systematic search of English peer-reviewed articles, clinical trial registries, grey literature databases and other online sources was performed using the PRISMA-S Guidelines for In-Vivo and In-Vitro studies. Qualitative data synthesis was performed to analyse sample dimensions, acrylic used, treatments of nanoparticles, methods used for testing and effect of size and percentage of nanoparticle. Risk of bias assessment was done using modified Cochrane risk of bias tool. Results: Out of 1376 articles, 15 were included. TiO 2NP of size less than 30 nm was most frequently used. Both antimicrobial property and surface hardness improved irrespective of the size of the added TiO 2NP. Three studies reported increase in the surface roughness with less than 50 nm TiO 2NP.  3% TiO 2NP was most frequently used. On increasing the percentage, three studies reported an increase in antimicrobial property, while two studies found no change. With TiO 2NP greater than or equal to 3%, six studies reported an increase in surface hardness, while two reported increase in surface roughness. Large methodological variations were observed across studies. All studies except one were of moderate quality. Conclusions:   On addition of TiO 2NP to heat polymerized PMMA, the antimicrobial property and surface hardness improved irrespective of the size of the TiO 2NP, however, addition of nanoparticles less than 50 nm increased the surface roughness. Increasing the percentage of TiO 2NP increased the surface hardness but did not always increase the antimicrobial property. Addition of 3% TiO 2NP provided optimum results with regards to antimicrobial effect and surface hardness, but increase in the surface roughness.

Evaluation of Sagittal Inclination of Occlusal Plane and Horizontal Condylar Guidance Using Various Anterior Reference Points on Arcon and Nonarcon Articulators.

Aim: The aim of the study was to determine the effect of different anterior reference points during facebow transfer, on sagittal inclination of occlusal plane (SIOP) and horizontal condylar guidance (HCG) values obtained on arcon and nonarcon articulators. Materials and Methods: Facebow records of 25 participants were made and transferred to Hanau Wide-Vue (WV) and Hanau H2 (H2) articulators using conventional indirect transfer (CIT), superior annular groove (SAG), and inferior annular groove (IAG) as anterior reference points. Maxillary casts were mounted on each articulator followed by mandibular mountings. Protrusive interocclusal record was used to determine HCG, and SIOP was measured as an angle between the occlusal plane of mounted maxillary cast and upper member of the articulator. Both, HCG and SIOP were measured on a digital lateral cephalogram and the values obtained were compared with previously determined values from both the articulators. Intergroup comparison was done by analysis of variance and pair-wise comparison by Tukey post hoc test. Results: Values of SIOP significantly (P = 0.00) changed on both the articulators when CIT, SAG, and IAG were the anterior reference points. The ratio of SIOP and HCG on both articulators was comparable to that of the cephalogram for CIT, IAG, but it was substantially low for SAG. Conclusions: The variation of anterior reference point changes the value of SIOP recorded on Hanau WV and H2 articulators; however, it had no effect on HCG values recorded on both the articulators. The angle between SIOP and HCG changed with variations in superior-inferior position of the mountings on both articulators.

A cephalometric study to determine the plane of occlusion in completely edentulous patients.

AIM: Determination of the plane of occlusion in completely edentulous patients with the help of the ala-tragus line (Camper's plane) may be questioned. An attempt to devise an alternative method to determine the orientation of the plane of occlusion was made. MATERIALS AND METHODS: Cephalometric analysis was used to identify whether a correlation exists between the plane of occlusion of dentulous Indian individuals and other stable cranial landmarks. RESULTS: A negative correlation was found to exist between the occlusal Plane-FH plane angle and the porion-nasion-anterior nasal spine (PoNANS) angle. CONCLUSIONS: From the derived mathematical correlation, it was concluded that the angulation of the occlusal plane in completely edentulous subjects may be determined by taking a cephalogram at the diagnostic stage. Further, the clinical applicability of the derived mathematical formula (while determining the plane of occlusion) was tested on completely edentulous patients.

A cephalometric study to determine the plane of occlusion in completely edentulous patients: part I.

To determine the relationship between the plane of occlusion and the Camper's line (ala-tragus line). Lateral cephalograms of 105 dentulous subjects were obtained after outlining the tragus and the base of the ala of the nose with radiopaque markers. Tracings of the cephalograms were done and the relationship between the plane of occlusion and the Camper's line (ala-tragus line) was noted. The most common tragal reference as a posterior landmark for determination of plane of occlusion was found to be below inferior (in 30.48% of subjects), and inferior (in 24.76% of subjects). The least common tragal reference was found to be above superior (in 3.82% of subjects) followed by superior of tragus and the point between superior and middle of the tragus (in 6.66% of subjects). The tragal reference in this study population was more towards the inferior of the tragus, with most of the times being below the inferior border. Therefore, the orientation of the plane of occlusion using the superior of tragus as a posterior landmark (according to the widely accepted definition of Camper's line) may be considered to be questionable. Further, the use of the tragus as a posterior landmark for the orientation of the plane of occlusion may be questioned on the basis of the findings of this study.