Quintessence International, 07/2018

According to the Fifth German Oral Health Study, the caries experience in the German population is declining sharply. The number of teeth still present at an advanced age has also increased significantly in recent decades. This shows a clear trend towards long-term tooth preservation - possibly with fixed dental prostheses - which is further supported by the possibility to place implants to increase the number of abutments. The pronounced decline in caries experience has given Germany a leading international position in terms of dental health. But there is increasing evidence of risks associated with dental hard-tissue damage because of erosion/biocorrosion, attrition, and abrasion. The defect morphology of these wear-related lesions is different from that of caries lesions; occlusal surfaces are more often affected in the posterior region. Against this background, restorative treatment concepts have become significantly more differentiated in recent decades. Predominantly subtractive concepts to provide mechanical retention for the restoration using traditional cements are now replaced by less invasive, primarily defect-oriented procedures wherever feasible. In the case of pronounced dental hard-tissue loss, additive approaches also allow restorations that restore function. In addition, there are modifications of traditional procedures, such as defining the treatment goal in the lead-up to the treatment itself with the aid of a diagnostic wax-up. The wax-up provides orientation for the subsequent tooth preparation and allows a particularly economical approach to the removal of healthy dental hard tissue. Furthermore, the introduction of new preparation designs has contributed significantly to the preservation of dental hard tissue on the teeth to be restored. This article describes the principles of minimally invasive treatment using occlusal onlays for the reconstruction of severely worn occlusal surfaces. Keywords: adhesive technique, all-ceramic restorations, diagnostic wax-up, high-performance polymers, minimally invasive preparation, mock-up, occlusal onlays, occlusally oriented defect morphology, tabletops

Many endodontically treated teeth require a post to improve the retention of the coronal restoration, which necessitates removal of the coronal part of the gutta-percha from the canal by thermal method, among other techniques. However, this technique carries the risk of heat conduction to the attachment unit of the periodontium and infliction of permanent damage especially in cases where the remaining root's dentin walls are thin. The overall objective of this article is to report on the clinical manifestations, histologic description, and periodontal management of three cases of heat-induced damage following thermal removal of gutta-percha. Keywords: bone necrosis, gutta-percha, heat-induced, periodontal regeneration, thermal removal

This case report presents long-term results following horizontal root fracture of both maxillary central incisors in a 19-year-old woman with aggressive periodontitis. Due to extensive marginal bone loss and the close proximity of the fracture lines to the bottoms of the periodontal pockets, the prognosis of both teeth was uncertain at the time of the accident. Nevertheless, a conservative treatment strategy consisting of splinting and nonsurgical periodontal therapy was initiated. Follow-up at 12 years after the start of treatment revealed a stable situation from clinical and radiologic perspectives. Permanent fixation to the adjacent teeth and regular supportive periodontal care were the basis for a favorable long-term prognosis. Keywords: aggressive periodontitis, cervical root fracture, dental trauma, splinting

Objective: Interchangeable articulators are crucial for a precise clinical outcome. Lack of interchangeability will affect the accuracy of the occlusion of prosthetic restorations. The objective of this study was to evaluate the interchangeability of KaVo PROTARevo articulators. Method and Materials: KaVo PROTARevo semi-adjustable articulators in routine use were employed. Identical casts were transferred among the articulators and the distance between casts was measured using digital photos of sagittal and frontal aspects of each articulator by two independent examiners. Interchangeability was assessed and analyzed by designated software. Results: Inter-examiner reliability was found to be high. Of 231 possible pairs of articulators only 27 pairs were found to be interchangeable (less than 166 µm in all measured dimensions), and of the other 204 pairs of articulators at least one of the dimensions measured was larger than 166 µm. Conclusion: The majority of articulators tested did not pass the 166-µm criterion to establish them as interchangeable. Therefore, in order to maintain accuracy while producing restorations, it is advisable to use the same articulator throughout the entire process, both at the clinic and in the dental laboratory. Keywords: articulator, interchangeability, occlusal adjustment, occlusion, prosthodontics

Objective: The aim of this study was to assess the bleaching efficacy and impact on psychosocial and esthetics self-perception of a low-concentration (6%) hydrogen peroxide (H2O2) gel compared with a conventional (37.5%) H2O2 gel when used as an in-office treatment. Method and Materials: In total, 35 participants received two sessions of three 12-minute applications of treatment with 37.5% H2O2 on one side of the mouth and 6% H2O2 on the other. Color changes were measured objectively using total variation in color (ΔE) and subjectively using Vita Classical scale (ΔSGU). The Psychosocial Impact of Dental Aesthetic Questionnaire (PIDAQ) and Oral Health Impact Profile (OHIP-14) esthetic questionnaires were administered to measure self-perception and the psychosocial impact of the whitening procedure. Results: Both gels produced significant changes in tooth color at 1 and 3 months post-whitening. The objective efficacy (ΔE) of 37.5% H2O2 (9.06 ± 2.96) was significantly higher than that of 6% H2O2 (5.69 ± 3.06). The results of the subjective assessment were not statistically different. There was a positive impact on esthetic auto perception (OHIP-14, P < .05) and psychosocial impact (PIDAQ, P < .05) at the 3-month time point. Conclusion: Low concentration of H2O2 (6%) achieved effective bleaching (ΔE > 5 units) with good stability at 3 months accompanied by a positive psychosocial impact and enhanced self-perception. However, the traditional 35% concentration was objectively more effective. Keywords: low concentration, OHIP, PIDAQ, quality of life, tooth bleaching

Objective: This article presents a methodology of a comprehensive score for assessment and monitoring of dental implant success from the peri-implant tissue perspective. It involves only standard and minimally invasive techniques accessible to general dental practices, without the need for special equipment. Methods and Materials: The proposed score methodology combines existing consensual global knowledge regarding aspects of dental implant success with the standard examination tools accepted for regular recall assessment. The score is a sum of five three-grade parameters: bone level, peri-implant inflammation, amount of attached mucosa, tissues recession (ie, exposure of implant components to intraoral environment), and the horizontal buccal profile of the alveolar process. The name peri-implant tissue score (PITS) is derived from the intended primary use of monitoring the state of implants and the surrounding hard and soft tissues. With its emphasis on buccal-aspect tissues, the score is designed to aid the detection of early signs of tissues deterioration. Results: The use of the score is demonstrated on a sample pool of 869 retrospectively evaluated implants with airborne-particle-abraded, acid-etched surfaces with time in service from 0 to 12 years. The parameters constituting the score were statistically tested on correlation with a reference set of success criteria, on mutual cross-correlations, and on the invariance to the implants' time-in-service. The PITS demonstrated to be highly representative of the success criteria, offering a fine scale from 0 to 10, and reversibility. Conclusion: The PITS withstood the tests. It responds to an existing need in the field, is widely accessible and inexpensive, and, thus, shows promise for use in general dental practice. Keywords: dental implants, implant stability, implant status monitoring, peri-implant tissue, success score

Objective: The purpose of this retrospective study was to determine the efficacy of Invisalign in a large sample of patients compared to fixed appliances. Method and Materials: The test group consisted of 100 patients treated with Invisalign compared with a control group treated with conventional fixed appliances matched for sex, age, and initial severity of malocclusion based on the amount of anterior dental crowding (Little Index) and the Peer Assessment Rating (PAR Index) scores. The retainer used was a 0.0175-inch multistranded stainless-steel wire bonded from canine-to-canine in the mandibular arch and from lateral inisor-to-lateral incisor in the maxillary arch. A paired t test was used to compare both initial and final PAR scores. Results: There was an overall 80.9% improvement, and 63 subjects did not need any refinement. The mean number of aligners used was 14 (+ 15 for the refinements) in the maxillary arch and 29 (+ 14 for the refinements) in the mandibular arch. The mean duration of treatment was 14 months (+ 7 months for the refinements). Significant statistical differences were found in the posttreatment scores, within both the Invisalign group and the control group. No differences were found in the follow-up scores. Additionally, the duration of treatment was 4 months longer in the control group. Conclusion: More than 90% of the subjects treated with Invisalign achieved a significant improvement, as shown by the PAR scores. A need for additional aligners was reported for 37% of the patients. Fixed bonded retainers seem to be a good option in preventing tooth relapse after Invisalign and fixed conventional treatments. Keywords: aligner, Invisalign, occlusion, orthodontic appliances, orthodontic treatment, treatment outcome

Objective: To compare postoperative pain associated with palatal and tuberosity donor sites for soft tissue grafting, and to evaluate the outcomes in both the donor and recipient sites. Method and Materials: Twenty healthy nonsmokers requiring bilateral soft tissue grafts were recruited for the study. For the 10 patients who required free gingival graft (FGG), 10 epithelialized grafts were taken from the tuberosity and 10 from the palate. The other 10 patients who required coronally advanced flap (CAF) and connective tissue graft (CTG) received 10 de-epithelialized grafts from the tuberosity and 10 from the palate. A total of 20 receded areas were treated with CAF and CTG. A total of 20 mucogingival defects were treated by FGG. Pain level was reported by the patient using a subjective score on a scale of 0 to 10 (0 = no pain, 10 = very severe pain). The length, width, and thickness of the outcome was measured for the FGG group at 8 weeks. The percentage of root coverage along with the length, width, and thickness of the final outcome was measured for the FGG group as well as the CAF and CTG group. Results: Pain level in the tuberosity donor site was significantly lower than in the palatal donor site during the first 2 postoperative weeks (2.6 ± 2.16 versus 5.9 ± 2.74 respectively, P < .001). Mean gingival thickness of the healed tuberosity donor graft was greater than of the palatal donor grafts in both groups; for CAF and CTG group 2.9 ± 0.5 versus 2.3 ± 0.6 mm, respectively (P = .016); for FGG group 2.7 ± 0.7 versus 2.1 ± 0.7, respectively (P = .026). No differences were observed in the length or width of both grafted sites at an 8-week follow-up. No significant difference in the mean percentage of root coverage resulting from tuberosity or palatal donor sites was noted (67 ± 12% versus 62 ± 13%, respectively, P = .102). Conclusion: Soft tissue grafts harvested from the tuberosity site might provide a better option than soft tissue donor grafts obtained from the palate in terms of function and less postoperative pain.