Vertical Discrepancy in Height of Morse Cone Abutments Submitted to Different Torque Forces.

The present study aimed to evaluate the influence of manual torque (10 Ncm) versus clinical torque (30 Ncm), which is recommended by the manufacturer, on the total length of morse cone implant abutments. Twenty specimens were prepared and distributed into two groups: group 1 with ten analogs for morse cone type implant, and group 2 with ten morse type implants, size 4.3 × 15 cm. In each group, the distance between the implant platform to the top of the prosthetic abutment (abutment height) was measured and subjected to a torque of 10 Ncm. Then, the 30 Ncm torque was applied to the same abutment, and abutment height was measured. The distance between the top of the abutment and the implant/analog base was measured. In order to verify the clinical reproducibility of the experiment, comparisons between the abutment height of the analog at 10 Ncm and the implant at 30 Ncm were performed, showing a greater discrepancy in torque for the 10 Ncm analog (p < 0.05). In order to verify if the change in the laboratory protocol from 10 to 30 Ncm could minimize the differences in the height of the prosthetic abutments, the abutment height in groups 1 and 2 was compared with 30 Ncm, and no significant difference was observed (p > 0.05). The data indicated that the manual torque and the torque recommended by the manufacturer influence the total length of the prosthetic abutments of morse cone implants.

Comparative study of the polyvinyl siloxane technique with resin-splinted transfer copings used for multiple implant abutment impressions.

UNLABELLED: STATEMENTS OF PROBLEM: The lack of passivity in implant dentistry may result in failures. Therefore, impression is the first procedure in the fabrication of a passive prosthesis. The aim of this study is to compare the polyvinyl siloxane technique with a resin-splinted transfer copings used for multiple implant abutment impression. METHODS: A master cast was obtained from an edentate ridge. From the master cast, 30 casts were obtained using 3 different impression techniques. Control technique was made with polyvinyl siloxane. Resin-splinted transfer copings in condensation siloxane or irreversible hydrocolloid were used as test. The distances between analogs were obtained using a profile projector. Statistical analysis was carried out using 1-way analysis of variance. RESULTS: No significant difference among the 3 impression techniques (P > 0.05) was observed. CONCLUSION: Resin-splinted transfer copings in condensation siloxane or irreversible hydrocolloid produced impressions as accurately as polyvinyl siloxane.

Evaluation of compressive strength in the first premolars between young and elderly people: ex vivo study.

OBJECTIVE: This study evaluated the compressive strength of first maxillary premolars from young and elderly people. BACKGROUND: Findings have revealed that changes happening on dental structure lead to a higher susceptibility of tooth fracture. MATERIALS AND METHODS: Thirty teeth were divided into four groups as follows: G I (n = 7) premolars of elderly patients with fused roots, G II (n = 8) premolars of elderly with separate roots, G III (n = 7) pre-molars of young people with fused roots and G IV (n = 8) premolars of young people with roots separated. The roots were placed in polyvinyl chloride (PVC) cylinder and embedded in acrylic resin. Afterward, the samples were subjected to fracture by compressive strength in a universal testing machine. Loads were applied in continuous and progressive speed of 0.5 mm/min until the moment of fracture. The values found underwent statistical analysis (ANOVA α = 0.05). RESULTS: With regard to age, there was a statistical difference, the teeth of the elderly being more susceptible to fracture (p < 0.05). With regard to root morphology, no significant differences between both groups were observed (p > 0.05). CONCLUSION: It was concluded that with the methodology employed, the age factor was important with regard to fracture resistance to compression.

Crestal bone loss around submerged and exposed unloaded dental implants: a radiographic and microbiological descriptive study.

The successful maintenance of crestal bone surrounding dental implants is imperative for long-term implant success. Crestal bone loss is reportedly related to stress. However, early perforation and partial exposure of the implant's covering device are a focus for plaque accumulation, which, if left untreated, may result in inflammation. The objective of this study was to evaluate the crestal bone levels adjacent to submerged and exposed unloaded dental implants during the initial healing phase. In addition, the microbiota around exposed implants were studied. Bilateral implants were placed in the mandible of 10 patients. In one quadrant, the implants were covered by the flap. In the other quadrant, the flap was sutured, leaving the cover screws completely exposed. Standardized periapical radiographs were obtained at implant placement and 4 months later. Radiographs were digitalized, aligned, and analyzed with a computer-assisted method. Cultures were obtained from exposed implant sites. All patients showed more crestal bone loss around exposed dental implants compared to submerged implants. Prevotella sp., Streptococcus beta-hemoliticus, and Fusobacterium sp. were the microorganisms identified in most of the sites. The exposure of the implant covering device created foci for bacterial plaque accumulation, which may have facilitated periimplant crestal bone loss. The initial healing phase follow-up may be critical for implant success.

Uso de implantes osseointegrados na movimentaçäo dentária: relato de caso / The use of osseointegrated implants in tooth movement. A case report

O presente trabalho relata um caso clínico onde foi utilizado um implante osseointegrado, agindo como ancoragem para movimentaçäo ortodôntica. O caso exemplifica a importância de um diagóstico e plano de tratamento multidisciplinar, visando aprimorar o tratamento reabilitador de pacientes adultos com perdas múltiplas. É dado destaque para a necessidade de determinaçäo do local exato de colocaçäo do implante, para que sejam atendidos os objetivos ortodônticos e protéticos