Histopathology of ameloblastoma of the jaws; some critical observations based on a 40 years single institution experience

The aim of the present study is to examine all cases of intraosseous benign ameloblastomas treated between 1970 and 2010 in a single institution and to look for a possible correlation between the histopathological aspects and the demographical and clinical parameters, as well as the treatment outcome. The data of a total number of 44 patients were retrieved from the records. Nine patients were excluded because of doubt about the correct diagnosis (8 patients) or because of an extra-osseous presentation (1 patient). No statistically significant differences were found between the histopathological (sub)types of ameloblastomas and the demographical and clinical parameters, nor between the histopathological (sub)types and treatment outcome. Of the 28 patients treated by enucleation, in 17 patients one or more recurrences occurred, with no significant predilection for any histopathological (sub)type, including the unicystic type. There were no significant differences in the recurrence rate after enucleation in patients below and above the age of 20 years either. In six out of 17 patients with a recurrence, the recurrent lesion showed a different histopathological subtype than was encountered in the primary. In two cases a change from solid/multicystic to desmoplastic ameloblastomas was noticed. In conclusion, the current histopathological classification of benign intraosseous ameloblastoma does not seem to have clinical relevance with the possible exception of the luminal unicystic ameloblastoma that has been removed in toto, unfragmented. Since no primary desmoplastic ameloblastomas were encountered in the present study no further comments can be made on this apparently rare entity. © Medicina Oral S. L

Three-year survival of single- and two-surface ART restorations in a high-caries child population

The aim of this study was to evaluate the survival of single- and two-surface atraumatic restorative treatment (ART) restorations in the primary and permanent dentitions of children from a high-caries population, in a field setting. The study was conducted in the rainforest of Suriname, South America. ART restorations, made by four Dutch dentists, were evaluated after 6 months, 1, 2, and 3 years. Four hundred seventy-five ART restorations were placed in the primary dentition and 54 in first permanent molars of 194 children (mean age 6.09 ± 0.48 years). Three-year cumulative survivals of single- and two-surface ART restorations in the primary dentition were 43.4 and 12.2%, respectively. Main failure characteristics were gross marginal defects and total or partial losses. Three-year cumulative survival for single-surface ART restorations in the permanent dentition was 29.6%. Main failure characteristics were secondary caries and gross marginal defects. An operator effect was found only for two-surface restorations. The results show extremely low survival rates for single- and two-surface ART restorations in the primary and permanent dentitions. The variable success for ART may initiate further discussion about alternative treatment strategies, especially in those situations where choices have to be made with respect to a well-balanced, cost-effective package of basic oral health care

Digital protocol for reference-based guided surgery and immediate loading: a prospective clinical study

PURPOSE: To evaluate the performance of a computer-aided three-dimensional planning protocol in combination with previously inserted reference mini-implants and CAD/CAM technology to restore completely edentulous patients. The study evaluated implant and superstructure survival in a prospective clinical trial. MATERIALS AND METHODS: The plan protocol called for treatment of 35 patients who were edentulous in either arch. Mini implants were used to establish a platform for computed tomography and fixation of the surgical template. The planning software based on three-dimensional simulation was used to plan ideal implant placement, digitally integrating the future prosthetic and anatomical situations to design the definitive superstructure. RESULTS: A total of 35 patients, 20 with edentulous maxillae, 10 with edentulous mandibles, and 5 patients with edentulism in both arches were treated. All patients received definitive prostheses on the day of surgery. The majority of patients treated in maxilla underwent a sinus graft procedure to achieve sufficient bone to place implants. A total of 40 superstructures were inserted and immediately loaded. Of the 240 inserted implants, 229 (95.4%) survived, with 146 (93.6%) and 83 (98.8%) implants in the maxillary and mandibular arches, respectively. Of the 10 implants that failed in the maxilla, 9 occurred in patients with an augmented sinus. All definitive restorations demonstrated clinically acceptable fit. CONCLUSIONS: When evaluating implant and superstructure survival, reference-based guided surgery seems to be a reliable treatment option for edentulous patients. The CAD/CAM superstructure, inserted and loaded immediately after guided implant insertion, demonstrated acceptable fit to the underlying implants

Digital protocol for reference-based guided surgery and immediate loading: a prospective clinical study

PURPOSE: To evaluate the performance of a computer-aided three-dimensional planning protocol in combination with previously inserted reference mini-implants and CAD/CAM technology to restore completely edentulous patients. The study evaluated implant and superstructure survival in a prospective clinical trial. MATERIALS AND METHODS: The plan protocol called for treatment of 35 patients who were edentulous in either arch. Mini implants were used to establish a platform for computed tomography and fixation of the surgical template. The planning software based on three-dimensional simulation was used to plan ideal implant placement, digitally integrating the future prosthetic and anatomical situations to design the definitive superstructure. RESULTS: A total of 35 patients, 20 with edentulous maxillae, 10 with edentulous mandibles, and 5 patients with edentulism in both arches were treated. All patients received definitive prostheses on the day of surgery. The majority of patients treated in maxilla underwent a sinus graft procedure to achieve sufficient bone to place implants. A total of 40 superstructures were inserted and immediately loaded. Of the 240 inserted implants, 229 (95.4%) survived, with 146 (93.6%) and 83 (98.8%) implants in the maxillary and mandibular arches, respectively. Of the 10 implants that failed in the maxilla, 9 occurred in patients with an augmented sinus. All definitive restorations demonstrated clinically acceptable fit. CONCLUSIONS: When evaluating implant and superstructure survival, reference-based guided surgery seems to be a reliable treatment option for edentulous patients. The CAD/CAM superstructure, inserted and loaded immediately after guided implant insertion, demonstrated acceptable fit to the underlying implants

Color coverage of a newly developed system for color determination and reproduction in dentistry

Objectives A newly developed system for color determination and reproduction is logically arranged and systematically combines a few components to acquire its broad color range. The objective was to evaluate color coverage of human teeth with the range of the new system and to compare it with other existing systems. Methods The systems for color determination used in this study were: New system Standard (NS), New system Expanded (NE), Vita Classical (VC) and Vita 3D-Master (V3D) (Vita Zahnfabriek, Germany), Vintage Halo (VH) (Shofu, Japan), Chromascope (CH) (Ivoclar Vivadent, Lichtenstein). The tabs of all systems were measured with digital spectrophotometer, SpectroShade-Micro (MHT, Italy), and their L*a*b* values were compared with the L*a*b* values of 198 teeth (mean age = 30.10; SD = 13.15) to obtain their coverage errors. The ΔE ≤ 1.6 was established as threshold for perceptibility. Results Wilcoxon-signed rank test showed that the coverage of the teeth with the NE range was the best, as indicated by the lowest mean minimal ΔE value, followed by the NS range. Both ranges had statistically significant lower mean minimal ΔE values than all the other systems (p > 0.01). The percentage of ΔE ≤ 1.6 was significantly higher for NS and NE range than for the other systems (p > 0.01). Conclusions The newly developed color determination and color reproduction system could cover the range of human teeth, used in this study, below the level of perceptibility (ΔE ≤ 1.6) better than four other available contemporary systems