STATEMENT OF PROBLEM: Over the years, resin-bonded fixed partial dentures (RBFPDs) have gone through substantial development and refinement. Several studies examined the biomechanics of tooth preparation and framework design in relation to the success rate of RBFPDs and considered retention and resistance form essential for increase of clinical retention. However, these criteria required preparations to be more invasive, which violates not only the original intentions of the RBFPD, but may also have an adverse effect on retention due to loss of enamel, an important factor in bonding. PURPOSE: The object of this in vitro study was to compare the dislodgement resistance of the new types of RBFPDs, the conventional three-unit fixed partial denture, and conventional design of RBFPD (Maryland bridge). MATERIAL AND METHODS: Fifty resin mandibular left second premolars and second molars were prepared on dentiforms, according to the RBFPD design. After model fabrication (five group, n = 10), prostheses were fabricated and cemented with zinc phosphate cement. After cementation, the specimens were subjected to tensile loading at a cross head speed of 4 mm/min in a universal testing machine. The separation load was recorded and analyzed statistically using one-way analysis of variance followed by Duncan's multiple range test. RESULTS: Group V, the pin-retained RBFPDs, had the highest mean dislodgement resistance, whereas specimens of group II, the conventional RBFPDs, exhibited a significantly lower mean dislodgement resistance compared to the other 4 groups (P < .05). There were no significant differences between group I, III, and IV in terms of dislodgement resistance (P > .05). Group V had the highest mean MPa (N/mm2) (P < .05). There was no significant difference between groups I, II, III and IV (P > .05). CONCLUSION: Within the limits of the design of this in vitro study, it was concluded that: 1. The modified RBFPDs which utilizes the original tooth undercuts and requires no tooth preparation, compared with the conventional design of RBFPDs, has significantly high dislodgement resistance (P < .05). 2. The modified RBFPDs which utilizes the original tooth undercuts and requires minimal tooth preparation, compared with the conventional FPDs, has significantly no difference in retention and dislodgement resistance)(P > .05). 3. The pin-retained FPDs showed a high dislodgement resistance compared to the conventional three-unit FPDs (P < .05).
Bicuspid ; Biomechanics ; Cementation ; Collodion ; Dental Enamel ; Denture, Partial, Fixed ; Head ; Intention ; Molar ; Phosphates ; Prostheses and Implants ; Retention (Psychology) ; Tooth ; Tooth Preparation ; Zinc Compounds ; Zinc Phosphate Cement

PURPOSE: The object of this clinical study was to evaluate the short-term outcome of modified resin-bonded fixed partial dentures which utilizes the original tooth undercuts and different path of insertion of components. MATERIALS AND METHODS: 71 units of modified RBFPDs that were used in 21 patients at the Department of Prosthodontics, College of Dentistry, Yonsei University were evaluated. The follow-up period was up to 25 months, the mean being 7 months. Survival rate, mobility, percussion, probing depth, bleeding on probing, plaque index was recorded and radiographs were taken to monitor alveolar bone loss. RESULTS & CONCLUSION: Within the limits of this short term retrospective study, it was concluded that: 1. No mechanical failure such as debonding or fracture of the framework was found during the follow-up period. 2. The periodontal apparatus was stable and no clinical change was observed after prosthetic treatment. 3. No significant marginal bone loss was found in the radiographic evaluation.
Dentistry ; Denture, Partial, Fixed ; Follow-Up Studies ; Hemorrhage ; Humans ; Organothiophosphorus Compounds ; Percussion ; Prosthodontics ; Retrospective Studies ; Survival Rate ; Tooth

Foreign body aspiration in dental clinics is the most common cause of respiratory emergencies. There are no reports on foreign body aspiration during dental treatment under stable general anesthesia because the patient neither has voluntary movements nor reflex actions. This is a case report on the fall of a prosthesis in the larynx, which occurs rarely under general anesthesia. During the try-in procedure, the prosthesis slid from the surgeon's hand and entered the retromylohyoid space, and while searching for it, it passed down the larynx to the endotracheal tube balloon, leading to a dangerous situation. The prosthesis was promptly removed using video-assisted laryngoscope and forceps, and the patient was discharged without any complications.
Anesthesia, General ; Dental Clinics ; Emergencies ; Foreign Bodies ; Hand ; Humans ; Laryngoscopes ; Larynx ; Prostheses and Implants ; Reflex ; Surgical Instruments

Patients with disabilities have difficulties tolerating in-office dental treatment due to limitations relating to cooperation and/or physical problems. Therefore, they often require general anesthesia or sedation to facilitate safe treatment. When deciding on dental treatment under general anesthesia, the plan should be carefully determined because compared to general patients, patients with disabilities are more likely to experience anesthetic complications because of their underlying medical conditions and potential drug interactions. Clinicians prefer simpler and more aggressive dental treatment procedures, such as extraction, since patients with impairment have difficulty maintaining oral hygiene, resulting in a high incidence of recurrent caries or restorative failures. This study aimed to review the available literature and discuss what dentists and anesthesiologists should consider when providing dental treatment to patients with severe disability under general anesthesia.

Issues related to the control of seizures and bleeding, as well as behavioral management due to mental retardation, render dental treatment less accessible or impossible for patients with Sturge-Weber syndrome (SWS). A 41-year-old man with SWS visited a dental clinic for rehabilitation of missing dentition. A bilateral port-wine facial nevus and intraoral hemangiomatous swollen lesion of the left maxillary and mandibular gingivae, mucosa, and lips were noted. The patient exhibited extreme anxiety immediately after injection of a local anesthetic and required various dental treatments to be performed over multiple visits. Therefore, full-mouth rehabilitation over two visits with general anesthesia and two visits with target-controlled intravenous infusion of a sedative anesthesia were planned. Despite concerns regarding seizure control, bleeding control, and airway management, no specific complications occurred during the treatments, and the patient was satisfied with the results.
Adult ; Airway Management ; Anesthesia* ; Anesthesia, General ; Anxiety ; Dental Clinics ; Dentition ; Gingiva ; Hemorrhage ; Humans ; Infusions, Intravenous ; Intellectual Disability ; Lip ; Mouth Rehabilitation* ; Mouth* ; Mucous Membrane ; Nevus ; Rehabilitation ; Seizures ; Sturge-Weber Syndrome*

Issues related to the control of seizures and bleeding, as well as behavioral management due to mental retardation, render dental treatment less accessible or impossible for patients with Sturge-Weber syndrome (SWS). A 41-year-old man with SWS visited a dental clinic for rehabilitation of missing dentition. A bilateral port-wine facial nevus and intraoral hemangiomatous swollen lesion of the left maxillary and mandibular gingivae, mucosa, and lips were noted. The patient exhibited extreme anxiety immediately after injection of a local anesthetic and required various dental treatments to be performed over multiple visits. Therefore, full-mouth rehabilitation over two visits with general anesthesia and two visits with target-controlled intravenous infusion of a sedative anesthesia were planned. Despite concerns regarding seizure control, bleeding control, and airway management, no specific complications occurred during the treatments, and the patient was satisfied with the results.
Adult ; Airway Management ; Anesthesia* ; Anesthesia, General ; Anxiety ; Dental Clinics ; Dentition ; Gingiva ; Hemorrhage ; Humans ; Infusions, Intravenous ; Intellectual Disability ; Lip ; Mouth Rehabilitation* ; Mouth* ; Mucous Membrane ; Nevus ; Rehabilitation ; Seizures ; Sturge-Weber Syndrome*

Paresthesia is an altered sensation of the skin, manifesting as numbness, partial loss of local sensitivity, burning, or tingling. The inferior alveolar nerve (IAN) is the third branch of the trigeminal nerve and is very important in dental treatment. IAN paresthesia may occur after various dental procedures such as simple anesthetic injections, surgical procedures, and endodontic treatment, and is reported to range from 0.35% to 8.4%. The altered sensation usually follows immediately after the procedure, and reports of late onset of nerve involvement are rare. This report presents a rare case of delayed paresthesia after dental surgery and discusses the pathophysiology of IAN delayed paresthesia.
Burns ; Hypesthesia ; Mandibular Nerve ; Paresthesia ; Sensation ; Skin ; Trigeminal Nerve

STATEMENT OF PROBLEM: Since the introduction of the concept of osseointegration in dental implants, high long-term success rates have been achieved. Though the use of dental implants have increased dramatically, there are few studies on domestic implants with clinical and objective long-term data. PURPOSE: The aim of this retrospective study was to provide long-term data on the Implantium(R) implant, which features a sandblasted and acid-etched surface and internal connection with microthreads. MATERIAL AND METHODS: 106 Implantium(R) implants placed in 38 patients at Yonsei University Hospital were examined to determine the effect of various factors on implant success and marginal bone loss, through clinical and radiographic results during a 6 to 30 month period. RESULTS: 1. Out of a total of 106 implants placed in 38 patients, one fixture was lost, resulting in a 99.1% cumulative survival rate. 2. Among the 96 implants which were observed throughout the study period, the survival rates were 97.0% in the maxilla and 100% in the mandible. The survival rate in the posterior regions was 98.9% and 100% in the anterior regions. 3. The mean bone loss during the first year after prosthesis placement was 0.17 mm, while the mean annual bone loss after the first year was 0.04 mm, which was statistically less than during the first year (P < .05). 4. There was no significant difference in marginal bone loss according to age during the first year (P > .05), but after the first year, the mean annual bone loss in patients above 50 years was significantly greater (P < .05) compared with patients under 50 years. 5. No significant difference in marginal bone loss was found according to the following factors: gender, jaw, location in the arch, type of implant (submerged or non-submerged), presence of bone grafts, type of prostheses, and type of opposing dentition (P < .05). CONCLUSION: Based on these results, the sole factor influencing marginal bone loss was age, while factors such as gender, jaw, location in the arch, type of implant, presence of bone grafts, type of prostheses and type of opposing dentition had no significant effect on bone loss. In the present study, the success rate of the Implantium(R) implant with a SLA surface and internal connection with microthreads was satisfactory up to a maximum 30 month period, and the marginal bone loss was in accord with the success criteria of dental implants.
Dental Implants ; Dentition ; Humans ; Jaw ; Mandible ; Maxilla ; Osseointegration ; Prostheses and Implants ; Retrospective Studies ; Survival Rate ; Transplants

Ankylosed tooth is defined as 'the discontinuance of normal passive tooth eruption without any mechanical barrier'. Ankylosed tooth treatment is a challenge to dental clinicians. In treatment of maxillary molar ankylosis cases there are risks of oro-antral fistula, displacement of root fragments into the maxillary sinus, as well as the necessity for providing additional sinus bone augmentation for future implant placement. In this study, we suggested a new technique using a piezoelectric device and a lateral side approach to the maxillary sinus leading to the simultaneous removal of the ankylosed maxillary molar and sinus grafting for the purpose of implant site development.
Ankylosis ; Displacement (Psychology) ; Fistula ; Maxillary Sinus ; Molar ; Tooth ; Tooth Eruption ; Transplants

PURPOSE: On maxillofacial tumor patients, oral implant placement prior to postoperative radiotherapy can shorten the period of prosthetic reconstruction. There is still lack of research on effects of post-implant radiotherapy such as healing process or loading time, which is important for prosthodontic treatment planning. Therefore, this study evaluated the effects of post-implant local irradiation on the osseointegration of implants during different healing stages. MATERIALS AND METHODS: Custom-made implants were placed bilaterally on maxillary posterior edentulous area 4 weeks after extraction of the maxillary first molars in Forty-eight Sprague-Dawley rats. Experimental group (exp.) received radiation after implant surgery and the other group (control) didn't. Each group was divided into three sub-groups according to the healing time (2, 4, and 8 week) from implant placement. The exp. group 1, 2 received 15-Gy radiation 1 day after implant placement (immediate irradiation). The exp. group 3 received 15-Gy radiation 4 weeks after implant placement (delayed irradiation). RESULTS: The bone mineral density (BMD) was significantly lower in the immediate irradiation groups. BMD was similar in the delayed irradiation group and the control group. The irradiated groups exhibited a lower bone-to-implant contact ratio, although the difference was not statistically significant. The irradiated groups also exhibited a significantly lower bone volume and higher empty lacuna count than the control groups. No implant failure due to local irradiation was found in this study. CONCLUSION: Within the limits of this study, the timing of local irradiation critically influences the bone healing mechanism, which is related to loading time of prostheses.
Bone Density ; Head and Neck Neoplasms ; Humans ; Molar ; Osseointegration ; Pilot Projects* ; Prostheses and Implants ; Radiotherapy ; Rats, Sprague-Dawley