Journal of Nepalese Prosthodontic Society

Dynamic Navigation: A Novel Tool for Dental Implant Surgery

2023-03-19T15:40:49+00:00

Dynamic navigation is an advanced technology that has revolutionized dental implant surgeries. Before being used in implant dentistry, navigation technique has been practiced in neurosurgery for performing minimally invasive brain surgeries. Navigation surgery for implant placement can be broadly categorized as dynamic and static navigation. The static navigation uses a static surgical guide for the sequential drilling of the osteotomy site and the implant placement. The static navigation can either be fully guided or partial/half-guided.

Dynamic navigation is a computer-assisted implant placement technique that uses real-time imaging to guide the implant placement procedure. In dynamic navigation, three-dimensional (3D) software monitors and tracks the bone drilling and implant placement in real-time during the entire procedure. This technique involves prosthetically driven virtual implant placement planning with Cone Beam Computed Tomography (CBCT) before the implant surgery. The 3D image of the patient is analyzed in a CBCT scan. This image is then used to plan the placement of the implant and create a surgical guide. A resin guided template is 3D printed or milled which is used during the surgery. The CBCT scan images are transferred into a 3D virtual image using digital software, which allows 3D viewing of the structures using Computer Aided Design (CAD). A calibrated special navigation instrument with specific software guides the bone drilling sequence and the implant placement. The drilling procedure is completely tracked and the patient’s anatomy and the surgical procedures in real time is shown in a 3D software. The use of real-time imaging and computer-aided technology ensures that the implant is placed precisely in the desired location, reducing the risks associated with conventional implant placement. Dynamic navigation is an effective and precise method that allows for more accurate placement of dental implants, which reduces the chance of damaging anatomical structures. It also gives clinicians the possibility to modify the planned surgical approach during the surgery. Additionally, because the implant is placed more accurately, there is less risk of implant failure. However, a learning curve and a training period are required before one masters this novel technology. Dynamic navigation can potentially become a preferred method for dental implant placement in the near future.

Fabrication of Silicon Prosthesis For a Partial-Auricular Defect in an Eight- Year-Old Patient: A Case Report

2023-03-19T16:28:59+00:00

Loss of the external ear can be congenital or acquired due to accidental trauma or malignant disease. Patients usually seek the prosthetic treatment for defects in head and face area when they feel that their function or esthetics are compromised. Literatures show that most of the prosthesis are fabricated in adult patients. Most of the time, dependence of the children on the parents for decision making and finances overshadows the psychological needs and perspectives of children. Present care report highlights the fabrication of silicone prosthesis for partial auricular defect in an eight-year-old child patient, who was conscious about his appearance due to the external defect in his pinna.

Use of Sectional Tray Design in Recording Edentulous Impressions for Microstomia Patients: A Case Report

2023-03-19T16:34:29+00:00

Prosthetic rehabilitation of patients with microstomia presents a major challenge to dentist as limited oral opening makes access to the oral cavity for any dental procedure difficult. The primary hurdle during the fabrication of dentures in such patient is making an impression. This article describes the treatment of a patient with microstomia where maxillary and mandibular custom sectional impression trays were used for making definitive impressions.

Detachable Cheek Plumper Using Orthodontic Lingual Button For Improved Denture Esthetics: A Clinical Technique

2023-03-19T17:30:28+00:00

Following loss of teeth and residual ridge resorption, facial esthetics is highly affected. The rehabilitation of lost structures should not be only aimed at replacing the lost teeth but facial changes associated with the edentulism should also be addressed. Objective of this technique article was aimed to improvise the excessive shrunken cheek appearance through fabrication of customized detachable cheek plumper. In this article, a novel, simple and easy technique has been described to fabricate a detachable cheek plumper for the management of shrunken cheek appearance using modified orthodontic lingual button and elastic tooth separator. Following fabrication of detachable cheek plumper and insertion, shrunken cheek appearance was improved and overall facial esthetic was enhanced. Cheek plumpers are simple to make and offer a noninvasive and cost-effective option for patients with sunken cheeks who want to improve their facial look. Patient’s aesthetics and psychological well-being benefit from this treatment. The use of detachable cheek plumper improves patient comfort, resulting in higher acceptance of the prosthesis.

Two and a Half Years Follow of the Pontic Site Development with Root Submergence Technique: A Case Report

2023-03-19T16:46:36+00:00

A soft tissue drape that is formed around the tooth, as it emerges from the bone, has both aesthetic and functional significance. Post-extraction soft and hard tissue changes are inevitable and it leads to a buccal concavity. The pontics for tooth or implant supported fixed partial denture in such cases appear longer. Preservation of a part of root preserves the periodontal apparatus and hence facilitates the optimal region for the pontic site development. This case report describes root submergence technique for pontic site development in maxillary anterior tooth-supported FPD with a follow up of two and a half years.

Prosthetic Rehabilitation of Patients with Maxillary Defects Post Mucormycosis: Case Series

2023-03-19T16:49:44+00:00

Mucormycosis has emerged as an epidemic within a pandemic of COVID 19 in India. It has emerged especially during second wave of COVID 19. Four major factors which are critical for the treatment of mucormycosis are rapidity of diagnosis, reversal of underlying predisposing factors (if possible), appropriate surgical debridement of infected tissue and appropriate antifungal therapy. Patient with maxillary resection present a challenging situation for the prosthodontist. Prosthetic rehabilitation is often difficult to achieve in such cases due to absence of many teeth and lack of favorable tissue undercuts. Obturator prosthesis should recreate the partition between oral and nasal cavities to restore oral function and esthetics. This case series presented the prosthodontic management of patients with hemimaxillectomy and premaxillary resection secondary to mucormycosis using maxillary interim obturator.

The Effect of Storage Time on the Dimensional Stability of Zinc Oxide Eugenol Impression Material Under Dry and Moist Conditions - An In- Vitro Study

2023-03-19T16:04:13+00:00

Introduction: Accurate impression is an important factor to fabricate accurate dental casts and ultimately accurate dental prostheses. Due to time constraints, sometimes there is need of storing impression for some time which may alter the dimension. The objective of this study was to evaluate the dimensional stability of zinc oxide eugenol impression paste at different time intervals and in two
conditions, dry and wet storage.

Methods: Sixty study molds of zinc oxide eugenol impression material were prepared according to American dental Association specification no 19 for non-aqueous elastic dental impression materials and the distance between two specific lines were measured at different time intervals. The paired t test was utilized to assess the difference in mean dimension of the molds from specified time to the original measurement immediately after setting.

Results: In dry storage condition, the dimensional changes were not seen up to 24 hours, but at 36 hours, there is statistically significant dimensional change. In wet condition, there was significant change in dimension after 6 hours onwards.

Conclusion: The dimensional change was not significant up to 24 hours in dry condition. Thus, it can be poured up to 24 hours after setting. Dimensional stability was not seen after 6 hour and hence is recommended to pour within 30 minutes if kept under wet condition.

Knowledge and Awareness Regarding Denture Staining Amount Complete Denture Wearers: A Descriptive Questionnaire Survey

2023-03-19T16:11:57+00:00

Introduction: Improper denture hygiene leads to denture staining as well as various lesions of the oral mucosa associated with wearing of removable dentures. The aim of the study is to evaluate the knowledge and awareness regarding denture staining amount complete denture wearers visiting Dental Department, Nobel Medical College and Teaching Hospital.

Methods: A descriptive cross‑sectional study was conducted among complete denture wearers visiting Dental Department of Nobel Medical College and Teaching Hospital. A survey was conducted through a printed standard questionnaire with 15 questions delivered to the patients. Data were collected and coded, the statistical analysis was done using SPSS statistical software package. Descriptive statistics were used for data analysis.

Results: The study showed that about 38 % of the patients were denture wearers for 6 months to 1 year. About 97% of patients consume coffee or tea regularly. About 65% of the patients consumed aerated beverages. 52% of the patients reported alcohol consumption habits. Tobacco chewing habit was reported by 7% of the patients. 17% of the patients reported cigarette smoking habit. Almost 92.9%% of the patients cleaned their dentures using some or the other method. 64% of the patients claimed to be aware of some or the other denture cleaning techniques. About 20.2% of the patients complained of halitosis, 11% of the patients complained of oral ulcers, and approximately 68.8% of the patients suffered from oral infections.

Conclusion: The knowledge and awareness regarding the cleaning and staining of dentures was not adequate among study participants. Patients have habit of consuming tea, coffee, aerated drinks and alcohol which could lead to staining of the acrylic dentures. Therefore, care and hygiene of dental prosthesis including removable dentures is a life-long exercise.

Awareness Regarding Occupational Hazards Among the Dental Students of a Medical College of Nepal

2023-03-19T16:17:49+00:00

Introduction: Dental students, during their clinical and preclinical practices, are constantly exposed to a number of occupational hazards. Such exposures lead to various ailments and diseases. The study was done to assess the awareness regarding occupational hazards among dental students in College of Medical Sciences, Nepal.

Methods: A questionnaire-based, descriptive cross-sectional study was conducted among the dental students from College of Medical Sciences, Nepal. Demographic details and awareness on different variables like bioaerosols, X-rays, blue light radiation, vibration, noise, posture, ergonomics, mercury vapour inhalation and percutaneous incidents, were assessed with the close-ended questions.
Questionnaire was delivered to the participants in paper-printed forms. Data analysis was done using SPSS version 17. Chi-square tests were done to find the association between the variables to education and gender and the level of significance was set at p<0.05.

Results: The mean knowledge score for the male students was higher than that for the female students and the difference was statistically significant (p<0.001). Fourth year students had the highest mean knowledge score (6.25±1.70) and second year students (2.71±2.43) had the lowest, and the scores were statistically significant (p<0.001). More than two-third of the students (72.8%) did not know that vibration causes peripheral neuropathy; more than three-fifth of them (61.7%) didn’t know that noise induced hearing loss is possible at dental settings and; about three-fifth of them (59.3%) did not know that X-ray hazards can be mitigated by barrier methods and position distance rule.

Conclusion: The awareness regarding the radiation hazards, vibration hazards and noise induced hazards seem to be limited among the dental students. The study suggests introducing specific intervention programs like occupational safety seminars, trainings or workshops, for the dental students, before the commencement of their practical classes.

Transformation-toughened zirconia: An overview

2023-03-19T16:23:41+00:00

Zirconia is a “metastable” ceramic, consisting of monoclinic, tetragonal, and cubic phases. Partially stabilized zirconia is preferred choice for dental use since they offer the opportunity to fabricate prosthesis which is not available with other ceramic materials. Phase transformation in zirconia ceramics represents one of the most remarkable innovations in the ceramic field. This phase transformation can have desirable consequences, increase in crack growth resistance which is referred to as “phase transformation toughening”. However, the phase-induced volumetric transformation can also have disastrous consequences, if not properly controlled. This article provides information on crystallography of zirconia and the main characteristics of the tetragonal to monoclinic transformation
and also discusses the positive (transformation toughening) and negative aspects (ageing/LTD) of the tetragonal to monoclinic transformation.