Mandibular Unilateral Paresthesia Following Implant Placement and Clinical Management: Clinical Case Report.

Dental implantology has been considered the mainstay in the rehabilitation of partial or complete edentulism. Nevertheless, complications and failures are occasionally encountered, and the most significant is the neurosensory disturbance. It not only causes persistent discomfort to the patient but frequently degrades the patient's oral health-related quality of life, even leading to a negative psychological impact. This paper presents a case report of a 65-year-old male patient who underwent the replacement of his missing tooth in the right mandibular region (46) with an implant-supported prosthesis two years ago. Since then, he has been experiencing numbness in the right side of the lip and occasional drooling of saliva from the right corner of the mouth. Clinical examination revealed the presence of a prosthetic crown supported by an implant in relation to 46 with inflamed and enlarged gingiva in the region with paresthesia of the right lower lip region. Radiological examination with orthopantomogram (OPG) and cone beam computed tomography (CBCT) revealed that the implant apex rested on the inferior alveolar nerve canal. Careful surgical retrieval of the well-osseointegrated implant was performed under local anesthesia in about seven days. The patient gradually experienced neurosensory improvement, and the paraesthesia was completely resolved in a six-week period. After complete recovery, as evaluated with an objective and subjective assessment, the edentulous site was successfully restored with a provisional fixed partial denture.

Graftless Immediate Dual Implant Anatomic Placement With Immediate Provisional Passive Loading and Definitive Hybrid Crown for the Restoration of Mandibular Molar: A Clinical Report.

Immediate implant placement is well-known science and treatment in implant dentistry. It is a multitasking treatment consisting of surgical, prosthodontic, and periodontal aspects, implemented to obtain long-term clinically esthetic and functioning prosthesis. Immediate placement enables clinicians to reduce the number of surgical steps and shorter treatment duration. It has become a standard surgical protocol in modern implant practice. According to existing literature, dual implant placement can be done to avoid any cantilever effect in a single implant and to distribute masticatory forces. This clinical report describes the extraction of an infected mandibular right first molar, (46, Federation Dentaire Internationale) followed by immediate dual placement of dental implants in the rinsed and cleansed sockets. The tooth was atraumatically extracted from the socket, and the latter was prepared to the required depth, and endosseous implants were placed in both the mesial and distal sockets. This atraumatic graft-free operating technique and immediate placement resulted in the preservation of hard and soft tissues. It also increased the patient's comfort, acceptance, and satisfaction due to immediate loading with a provisional removable prosthesis. This was later replaced with a dual screw-retained hybrid implant crown.

Escherichia coli Cellular Activity and Frontal Trizonal Evaluation of Microspace Between Implants and Abutments Under Calibrated Cyclic Stress.

AIM: To evaluate microspace and microleakage between implant and abutments subjected to pre- and post-calibrated cyclic stress. MATERIALS AND METHODS: Twelve screw-retained implant prostheses with BioHPP polyetheretherketone (PEEK) abutment (Noris Dental Implant System Ltd., Nesher, Israel) (Group I) and 12 screw-retained implant prostheses with computer-assisted design/computer-assisted manufacturing (CAD/CAM) milled zirconia abutment (DentGallop, Houston, TX, USA) (Group II) were connected to their respective implant, and the prosthetic screw was torqued to 30N/cm (Noris). The microspace was evaluated using scanning electron microscopy (SEM; TeScan, Brno, Czech Republic). Twenty-four samples were then induced to cyclic stress (Lokesh Industries, Pune, India) simulating 180 days duration of oral stress. The microspaces (Group IA and Group IIB) were measured post-cyclic stress. Group I and II were again renamed into Group Ia and Group IIb for microbial study. Both implant assemblies were immersed in fresh soybean casein digest broth (SCDB) (Himedia, Mumbai, India) and subsequently inoculated with 1.0µL E. coli suspension (Himedia) at the open end and incubated at 37ºC for seven days. After the incubation period, cellular activity was determined by the spread plate method, and total colony-forming units (CFU) were calculated. The results were evaluated using independent T and Mann-Whitney tests. RESULT: Average and microspace at the implant-abutment junction of Group I samples in the front right was 12.98µm, center 13.76µm, front left 13.22µm, and in Group II samples, the front right was 18.52µm, center 17.84µm, front left 18.58µm.After being subjected to cyclic loading, the mean levels of the vertical microgap for Group IA samples were: in the front right region 10.37µm, in the center 9.34µm, in the front left 10.51µm and in Group IIB samples front right was 14.59µm, center 13.39µm, front left 13.8µm. Independent t-tests showed insignificant differences between the two groups. The median value of microbial leakage of Group Ia samples after cyclic loading was 30 x 103 CFU/ml, and Group IIb samples were 42 x 103 CFU/ml and were significant. CONCLUSION: There was minimal variation in the mean microspace between the BioHPP PEEK abutment and CAD/CAM milled zirconia abutment, and it was insignificant before and after cyclic stress. BioHPP PEEK abutment-titanium implant interfaces showed significantly decreased microbial leakage than CAD/CAM milled zirconia abutment-titanium implant interfaces after cyclic stress.

Treatment Intricacies in Mandibular Implant-Supported Rehabilitation of a Patient With Down Syndrome: A Clinical Report.

Edentulism is considered a poor health condition and may compromise the quality of life. Prosthodontic replacement of missing teeth results in significant improvement of oral functions. Treating a patient with Down syndrome can pose clinical challenges in handling the emotional aspect as well as in rendering treatment. Careful oral analysis and diagnosis of the existing conditions in such patients will enable and pave the way for clinically acceptable treatment results. This clinical report describes the challenges encountered in the prosthodontic management of an edentulous young patient with Down syndrome.

Comparative evaluation of wear resistance of CAD-CAM zirconia and cast cobalt chromium alloy for indirect restorations against human enamel - An In Vitro study.

PURPOSE OF THE STUDY: To comparatively evaluate the wear resistance of two different posterior indirect restorative materials against human enamel. MATERIALS AND METHODS: Two different posterior indirect restorative materials of ten in each Group-I (Monolithic zirconia) (n = 10) and Group-II (Cast cobalt chromium) (n = 10) were formed into disc and used as a substrate for the wear test. Freshly extracted mandibular first premolars were used as a pin (antagonist) (n = 20). Pin-on-disc wear testing machine was used to simulate the masticatory parameters and evaluation of the wear parameters was done after 1,20,000 cycles, with load of 40N for specific duration. Data related to wear testing procedure were tabulated and evaluated. Results were statistically analyzed using Mann-Whitney test and Wilcoxon signed rank test. RESULTS: Mean surface roughness value (Ra value) obtained for Group-I disc test samples showed no statistical significance (P value < 0.05). Mean wear rate value of test disc samples was statistically significant between Group-I and Group-II (P value < 0.05). Mean surface roughness value was statistically significant between Groups-I and II before and after wear test (P value < 0.05). CONCLUSION: From the results obtained, it was found that the Group-I (Monolithic zirconia) exhibited higher wear resistance than Group-II (cast cobalt chromium) and causes less wear to the opposing enamel antagonist.

Evaluation of the Bioactivity of Surface Modified Polyetheretherketone (PEEK) as an Implant Material: An In Vitro Study.

PURPOSE: The purpose of this study was to evaluate the bioactivity of polyetheretherketone (PEEK) used as an implant material after surface modification by electron beam deposition of titanium. MATERIALS AND METHODS: Twenty-two samples of PEEK were obtained from a single manufacturer, water jet sectioned, and divided randomly into two groups of eleven each (Group I and Group II). Eleven PEEK samples from Group II were coated with Grade II commercially pure titanium by electron beam deposition technique. One representative sample from each group was evaluated for surface roughness, topography and composition using three dimensional surface profilometer, scanning electron microscope coupled with energy dispersive X-ray (SEM-EDX) analysis. Simulated body fluid (SBF) was prepared and calcium (Ca) content in it was quantitatively analyzed by inductively coupled plasma mass spectrometry (ICP-MS) technique. Ten samples from each group were then immersed in SBF for a period of 21 days and amount of calcium depletion was analyzed to determine the bioactivity of two groups. Surface characteristics and elemental composition of immersed samples were analyzed by SEM-EDX and correlated with results of ICP-MS tests. The data obtained were then subjected to statistical analysis using independent t-test. RESULTS: Group II samples showed a significant increase in surface roughness compared to Group I (P < 0.02). There were significant differences in Ca depletion of Group I and Group II samples when compared to preimmersion Ca content (P < 0.001). When compared between two Groups, Group II samples showed higher Ca depletion (P < 0.001). CONCLUSION: Within the limitations of this study, it was concluded that PEEK dental implants which were surface modified by electron beam deposition of titanium had enhanced bioactivity when compared to unmodified PEEK. Hence, they can serve as a valuable alternative to conventional dental implant materials.

Three-dimensional finite element analysis of the stress distribution pattern in the design modifications of U-shaped palatal major connector.

BACKGROUND: The U-shaped maxillary major connector is considered to be the least-desirable design by many prosthodontists as it lacks rigidity, which is a primary requisite for a major connector. AIMS AND OBJECTIVES: Design modifications in the U-shaped palatal major connector are desired because it lacks rigidity. The study also aimed to determine the best design when a U-shaped palatal major connector is indicated for clinical use. MATERIALS AND METHODS: The normal design and the design-modified models (modification 1, 2, 3, 4) were loaded at the functional cusps of the premolars and the molars with a magnitude of 200 N, 250 N and 300 N at angulations of 60 o and 90 o on both sides of the maxillary arch. Results for each loading were obtained as stress distribution colored images and numerical values were recorded. A three-dimensional finite element analysis study of the design-modified models was performed using two finite element softwares, namely PRO-E and IDEAS. RESULTS: The least stress value of 7.86 Megapascals (MPa) at 200 N, 60 o was recorded for the double-thickness design, followed by design 1, which was 8.03 MPa. The least stress value for the palatal mucosa and ligament was provided by design modification 1 (0.5 mm-thick U-shaped connector, 9 mm anteroposteiorly, 14.6 mm laterally), which was 9.78 MPa and 2.98 MPa, respectively. CONCLUSION: The double-thickness group exhibited the least internal stress for the U-shaped major connector. However, it delivered the greatest stress to the palatal mucosa and the periodontal ligaments.