Damages of anterior teeth that have filling need to be recovered in function. Remaking them by resin composite accompanied dentine element pin satisfied this requirement. The treatment provided for 16 teeth of 10 patients have showed the successful result.
Dental Restoration Failure ; Composite Resins

Dental Implantation, Endosseous ; Dental Implants ; Dental Restoration Failure ; Humans ; Prognosis

Dental bonding technique has become an essential technique for dental clinical practice over the past several decades. Dental adhesion is widely used in direct and indirect restorations. However, problems such as technique sensitivity, postoperative sensitivity, secondary caries and marginal discoloration always appear in the dental bonding procedures. Fiber post and all-ceramic restoration bonding are essential step in esthetic dentistry. If these problems are not well handled, it will result in failure of the restorations. Therefore, the aim of this article is to provide adequate consultations and advice for the clinical practitioners based on the author's experience and relevant literatures.
Ceramics ; Dental Bonding ; Dental Caries ; Dental Restoration Failure ; Humans

ABSTRACT Implant periapical lesion (IPL) is also known as retrograde peri-implantitis and as the name suggests, it involves inflammation surrounding the apical part of the dental implants. Previously, many studies have reported the event of IPL that further delays osseointegration, and some reported failure of implant placement due to this disease. In this article, we described two cases of early dental implant failure that was associated with active IPL and correlated the clinical and radiographical findings with the histopathological findings.
Dental Restoration Failure ; Dental Implants--adverse effects ; Periapical Tissue

With the comprehensive application and development of implant dentistry in recent years, multi-institutional data have supported a large number of clinical research findings. A consensus was gradually reached on the evaluation of the state and effect of implants and types of indicators that were selected after restoration. This study aims to examine the frequently used criteria to define treatment success in implant dentistry.
Dental Implants ; Dental Prosthesis Design ; Dental Prosthesis, Implant-Supported ; Dental Restoration Failure ; Treatment Outcome

Immediate-implant-immediate-loading restoration exhibits many advantages, such as recovery appearance, early function, short implant period, reduced operation frequency and trauma, and less pain, among others. This report introduced a case of immediate-implant-immediate-loading restoration failure because of implant neck split.
Dental Implantation, Endosseous ; Dental Prosthesis, Implant-Supported ; Dental Restoration Failure ; Humans

Dental Implantation, Endosseous ; methods ; Dental Implants ; Dental Restoration Failure ; Denture, Complete, Immediate ; Humans ; Jaw, Edentulous ; surgery

OBJECTIVE: This study aimed to investigate the effect of occlusal thickness design on fracture resistance of endocrowns restored with lithium disilicate ceramic and zirconia. METHODS: A total of 24 artificial first mandibular molars were randomly divided into four groups with six teeth in each group as follows: group lithium disilicate ceramic-2 mm (lithium disilicate ceramic, with an occlusal thickness of 2 mm and a retainer length of 4 mm); group lithium disilicate ceramic-4 mm (lithium disilicate ceramic, with an occlusal thickness of 4 mm and a retainer length of 2 mm); group zirconia-2 mm (zirconia, with an occlusal thickness of 2 mm and a retainer length of 4 mm); and group zirconia-4 mm (zirconia, with an occlusal thickness of 4 mm and a retainer length of 2 mm). After adhesive cementation (RelyX Ultimate Clicker), all specimens were subjected to thermocycling (10 000 cycles). The specimens were subjected to fracture resistance testing at a 135° angle to the teeth at a crosshead speed of 0.5 mm·min⁻¹ in a universal testing machine. Data were analyzed with ANOVA and Tukey's HSD test by SPSS 15.0. The failure modes were classified. RESULTS: The fracture resistances of groups lithium disilicate ceramic-
2 mm, lithium disilicate ceramic-4 mm, zirconia-2 mm, and zirconia-4 mm were (890.54±83.41), (2 320.87±728.57), 
(2 258.05±557.66), and (3 847.70±495.99) N respectively. Group zirconia-4 mm had the highest fracture resistance, whereas group lithium disilicate ceramic-2 mm had the lowest. CONCLUSIONS The fracture resistance of molar endocrown with zirconia is higher than that with lithium disilicate ceramic. Increasing the occlusal thickness can improve the fracture resistance but increase the risk of fracture of abutment.
Ceramics ; Crowns ; Dental Porcelain ; Dental Restoration Failure ; Dental Stress Analysis ; Materials Testing ; Zirconium

OBJECTIVE: To compare the effects of resin base and different retention depth on the fracture resistance of mandibular molars restored with nano-ceramic endocrowns. METHODS: Forty mandibular molars selected and randomly divided into 5 groups: ① The control group which was consisted of intact teeth, ② the non-resin base group, ③ the 2 mm retention depth group, ④ the 3 mm retention depth group, ⑤ the 4 mm retention depth group, respectively. After tooth preparation, in vitro root canal therapy was conducted, which was followed by endocrown design, production and adhesive of groups ②-⑤. All the samples were under load (N) of the universal mechanical testing machine after embedding. The fracture pattern of each sample was observed under stereomicroscope. Then the microstructure of the fracture surface was observed by scanning electron microscopy. RESULTS: The fracture loads of each group were respectively: the control group fracture load was (3 069.34±939.50) N; experimental groups: fracture load of (2 438.04±774.40) N for the group without resin base; fracture load of (3 537.18±763.65) N for the group with 2 mm retention depth. The fracture load of the retention depth 3 mm group was (2 331.55±766.39) N; the fracture load of the retention depth 4 mm group was (2 786.98±709.24) N. There was statistical significance in the effect of resin base and different retention depth on the fracture loads of molars restored with nano-ceramic endocrown (P < 0.05). Repairable fractures in each group were as follows: control group 2/8, non-resin base group 1/8, retention depth of 2 mm group 1/8, retention depth of 3 mm group 2/8, and retention depth of 4 mm group 0/8. The effects of the retention depth and the presence of resin base on the fracture resistance of the resin nano-ceramic endocrowns were statistically significant (P < 0.05). Scanning electron microscopy showed more arrest lines and small twist hackles on the fracture surface of the restorations with resin base (retention depths of 2 mm, 3 mm, and 4 mm), with cracks extending towards the root. In addition to the characteristics above, more transverse cracks parallel to the occlusal surface, pointing outwards from the center of the pulp cavity retention, were also observed on the fracture surface of the non-resin base restorations. CONCLUSION When molar teeth with nano-ceramic endocrowns are restored, resin base and the retention depth of 2 mm help the teeth to obtain optimal fracture strength.
Ceramics ; Composite Resins ; Dental Porcelain ; Dental Restoration Failure ; Dental Stress Analysis ; Materials Testing ; Molar

The implant prosthesis can be divided into the screw retained prosthesis and cement retained prosthesis. Each type has advantages as well as disadvantages which is unfavorable to maintain the implants. To overcome these drawbacks, T-screw system was developed. T-screw system which utilizes a lingual direction of the screw to retain the implant prosthesis, has advantages of retrievability of the prosthesis, passive fit, and possibility to form esthetic and functional occlusal surface. The prior prosthesis which utilized horizontal screws had difficulty in fabrication especially in the case of multiple units, and also limited use with all-ceramic prosthesis. In this case, fabricating the implant prosthesis by using the T-screw system showed superior results in easy maintenance, esthetics, and also functions. In addition, we are to report the method of using the T-screw system in implant prosthesis, such as multiple units of implant prosthesis and all ceramic prosthesis.
Ceramics ; Dental Implants ; Dental Prosthesis* ; Dental Prosthesis, Implant-Supported ; Dental Restoration Failure ; Dental Restoration Repair ; Esthetics ; Methods ; Peri-Implantitis ; Prostheses and Implants