Endosseous dental implant fractures an analysis of 21 cases

Implant fracture is an infrequent cause of implant failure. The present study evaluates 21 fractured implants, with an analysis of patient age and sex, the type, length and diameter of the implant, positioning in the dental arch, the type of prosthetic rehabilitation involved, the number of abutments and pontics, the presence or absence of distal extensions or cantilevers, and loading time to fracture. Implant fracture was more common in males than in females (15:4), and the mean patient age was 56.9 years. Most cases (n = 19) corresponded to implant-supported fixed prostheses - 16 with cantilevers of different lengths- while only two fractured implants were supporting overdentures instead of fixed prostheses. The great majority of fractured implants (80.9%) were located in the molar and premolar regions, and most fractured within 3-4 years after loading. It is important to know and apply the measures required to prevent implant fracture, and to seek the best individualized solution for each case - though complete implant removal is usually the treatment of choice

Complications of guided surgery and immediate loading in oral implantology: a report of 12 cases

Objectives: The growing interest in minimally invasive surgery, together with the possibility of fitting prostheses with immediate function, have led to the development of software capable of planning and manufacturing a surgical guide and prosthesis that can be placed upon conclusion of the implant surgery step. The present study evaluates the surgical and prosthetic complications of implant treatment with the guided surgery technique, together with patient comfort during and after treatment. Patients and methods: A retrospective observational study was made of 19 patients with partially or totally edentulous upper and/or lower maxillae, involving the placement of a total of 122 implants. All cases were planned and operated upon with the guided surgery technique. Results: A total of 122 implants were placed in 14 males and 5 females. The intraoperative surgical complications comprised a lack of primary stability, while the postoperative complications consisted of infections and a lack of implant osteointegration. Ten implants failed. The prosthetic complications in turn comprised loosening of the provisional prosthesis screws, prosthesis tooth fracture, and a lack of passive fit of the immediate prosthesis. The degree of patient satisfaction was evaluated using a verbal scale. Conclusions: Implant restoration with the guided surgery technique and immediate functional loading is a predictable procedure, provided patient selection and the surgical technique are adequate, affording lesser postoperative morbidity and increased patient satisfaction thanks to the immediate restoration of esthetics and function

Unbreakable PT symmetry of solitons supported by inhomogeneous defocusing nonlinearity

Peer Reviewed

Age-Related Tooth Wear Differs between Forest and Savanna Primates

Tooth wear in primates is caused by aging and ecological factors. However, comparative data that would allow us to delineate the contribution of each of these factors are lacking. Here, we contrast age-dependent molar tooth wear by scoring percent of dentine exposure (PDE) in two wild African primate populations from Gabonese forest and Kenyan savanna habitats. We found that forest-dwelling mandrills exhibited significantly higher PDE with age than savanna yellow baboons. Mandrills mainly feed on large tough food items, such as hard-shell fruits, and inhabit an ecosystem with a high presence of mineral quartz. By contrast, baboons consume large amounts of exogenous grit that adheres to underground storage organs but the proportion of quartz in the soils where baboons live is low. Our results support the hypothesis that not only age but also physical food properties and soil composition, particularly quartz richness, are factors that significantly impact tooth wear. We further propose that the accelerated dental wear in mandrills resulting in flatter molars with old age may represent an adaptation to process hard food items present in their environment.

Music-supported training is more efficient than functional motor training for recovery of fine motor skills in stroke patients

MOTOR IMPAIRMENTS ARE COMMON AFTER STROKE but efficacious therapies for these dysfunctions are scarce. Extending an earlier study on the effects of music-supported training (MST), behavioral indices of motor function were obtained before and after a series of training sessions to assess whether this new treatment leads to improved motor functions. Furthermore, music-supported training was contrasted to functional motor training according to the principles of constraint-induced therapy (CIT). In addition to conventional physiotherapy, 32 stroke patients with moderately impaired motor function and no previous musical experience received 15 sessions of MST over a period of three weeks, using a manualized, step-bystep approach. A control group consisting of 15 patients received 15 sessions of CIT in addition to conventional physiotherapy. A third group of 30 patients received exclusively conventional physiotherapy and served as a control group for the other three groups. Fine as well as gross motor skills were trained by using either a MIDI-piano or electronic drum pads programmed to emit piano tones. Motor functions were assessed by an extensive test battery. MST yielded significant improvement in fine as well as gross motor skills with respect to speed, precision, and smoothness of movements. These improvements were greater than after CIT or conventional physiotherapy. In conclusion, with equal treatment intensity, MST leads to more pronounced improvements of motor functions after stroke than CIT.

Maxillary dentigerous cyst and supernumerary tooth. Is it a frequent association?

Dentigerous cysts, also known as follicular cysts, are a relatively common pathology in our field. They are associated with unerupted or semi-erupted teeth and are usually not related to supernumerary teeth. OBJECTIVE: To describe a dentigerous cyst case associated to a supernumerary tooth. CASE-REPORT: A large-sized dentigerous cyst is described, associated with a supernumerary tooth, affecting the whole maxillary anterior area. Appropriate treatment consists of performing root canals and a Partsch II procedure with a cystectomy, extracting the unerupted teeth, carrying out an apicoectomy and retro-filling the affected teeth. The defect is filled with a bone xenograft. Possible therapeutic alternatives and the connection between the dentigerous cysts and supernumerary teeth are considered in the discussion.