Seiten: 166-167, Sprache: Englisch
Seiten: 169-175, Sprache: Englisch
Implant-related esthetic demands have increased tremendously in recent years. The presence of shallow papillae or open interproximal spaces (black triangles) are some of the most troubling dilemmas in dentistry. Among the many factors associated with the presence of papilla or papilla height, the interproximal bone is one of the main factors dictating the presence of an adequate papilla between implants. The present case report describes a patient with severe hard and soft tissue deficiencies with a high smile line in the esthetic zone, requiring multiple implants. The step-by-step process of the utilized techniques for achieving inter-implant papilla reconstruction through a multidisciplinary approach using both hard and soft tissue augmentation procedures, as well as soft tissue conditioning with customized abutments, is delineated.
Seiten: 177-185, Sprache: Englisch
Modern dentistry is focused on patient needs, with the current trend shifting from merely restoring the loss of function to pursuing the esthetic satisfaction of patients and professional operators, as well as achieving optimal and stable results. Ideal smile esthetics depend on the balance between white and pink components, and therefore papilla reconstruction is one of the most challenging goals in periodontal plastic surgery and restorative procedures. The present case report proposes a surgical technique for the combined treatment of RT2 and RT3 recession defects and interdental papilla loss by means of a modified coronally advanced flap with an interdental subepithelial connective tissue graft.
Seiten: 187-192, Sprache: Englisch
This paper reports on a study undertaken to ascertain the efficacy of the erbium:YAG laser (EYL) for peri-implantitis treatment. A total of 12 patients with bone loss resulting from peri-implantitis were involved in this study. The treatment protocol consisted of using the EYL for implant surface debridement and deproteinized bovine bone mineral (DBBM) for bone grafting. The following parameters were analyzed: probing pocket depth (PPD), clinical attachment level (CAL), bleeding on probing (BOP), bone levels (BLs), and the lipopolysaccharide levels before and after debridement with the EYL. This study found a statistically significant improvement in PPD, CAL, BOP, and BL at 3 and 12 months postoperative. Furthermore, a statistically significant decrease in implant-surface LPS levels was observed following debridement with the EYL. These findings show that using the EYL for debridement in peri-implantitis cases is effective in decreasing LPS levels. Moreover, after partial reconstruction with DBBM grafting, BLs were restored for at least 12 months. It was shown in one case that BLs had remained stable over 6 years, which also attests to the efficacy of this treatment. The combined use of EYL and DBBM could be effective for regenerative surgical peri-implantitis treatment.
Seiten: 195-204, Sprache: Englisch
A clinical case series of three patients is presented using a novel implant design to not only address primary stability but also to prevent damage to the labial bone plate and improve the interdental space for papillae preservation with immediate tooth replacement therapy. This unique implant design features an apicocoronal inverted body-shift in diameter (wide to narrow), shape (tapered to cylindrical), thread depth (deep to shallow), and thread pattern (V-shaped to square) to achieve uncompromised primary stability and esthetics, particularly in extraction sockets, in a singular body form. In addition, the implant possesses a prosthetic angle correction within the implant body to facilitate screw-retention of the restoration and avoid the risk of apical socket perforation.
Seiten: 207-214, Sprache: Englisch
The present clinical and histologic case reports describe the periodontal plastic approaches used for the correction of gingival deformities following free gingival grafting (FGG) procedures. Five patients with poor esthetic and functional outcomes following soft tissue grafting voluntarily requested corrective treatment due to differences in color, texture, thickness, and mucogingival junction (MGJ) alignment between grafted and adjacent tissue, or because of food retention apical to the grafted site. Plastic surgical approaches included eliminating the thick borders the graft, aligning the MGJ, and reducing the excessive apicocoronal dimension of the graft. Histologic images confirmed the morphologic differences between the graft and adjacent alveolar mucosa. After intervention, all treated sites achieved a satisfactory esthetic appearance and function, with a soft tissue anatomy indistinguishable from those of adjacent sites. All patients agreed that their goals for the treatment were completely fulfilled.
Seiten: 217-224, Sprache: Englisch
One of the chronic problems with traditional cement or screw retention of crowns to implants is the development of biologic and technical complications, including soft tissue complications, bone loss, screw loosening, loss of retention, and veneering material fractures. The purpose of this case series report is to document preliminary results, specifically crown retention, using a friction-fit connection of crown to abutment. A sample composed of patients who had one or more implants restored between July 1, 2019, and October 30, 2019, were enrolled in this retrospective case-control series. Each patient had their crown connected to the implant abutment using a friction-fit system. Patients were seen for routine follow-up for documentation of crown retention, and 24 crowns were followed. After 6 months of follow-up, 100% of the crowns retained retention and did not become loose under normal masticatory function. The use of a friction-fit connection provided excellent retention of the crown to the abutment over the 6-month follow-up period.
Seiten: 227-232, Sprache: Englisch
A postextraction socket is always open to different treatment possibilities. A straightforward clinical classification may help evaluate which surgical approach is best suited for the case being treated. Four different classes are defined on the basis of the local anatomy of the site, available bone volume, and soft tissue level. For every clinical situation, either immediate placement, early placement, alveolar ridge preservation, or staged approach can be selected as a treatment modality according to the classifications listed.
Seiten: 235-244, Sprache: Englisch
Immediate implant placement in molar sites has the potential to improve the patient experience by reducing the number of appointments and the overall treatment time. However, primary closure remains a technical challenge. The present prospective case series evaluated the soft tissue contours and the radiographic bone levels of 17 patients who received immediate implants in molar sites and a digitally customized CAD/CAM sealing socket abutment. At the 2-year follow-up, the mean buccal tissue contours at the most coronal portion were reduced horizontally by an average of 1 mm at 1, 2, 3, and 4 mm below the gingival margin. A mean 0.53-mm apical migration of the gingival margin was seen, and the mean interproximal bone level at the 2-year follow-up was 0.89 mm. The use of CAD/CAM-generated customized healing abutments in immediate molar sites yielded minimal hard and soft tissue changes at the 2-year follow-up.
Seiten: 245-251, Sprache: Englisch
This study aimed to assess how frequently the maxilla anatomy allows for lingualized immediate implants in the central incisor region with a screw channel that has an ideal distance of 1.5 mm from the incisal margin. The effect of abutments with angle correction on case selection will also be verified. A retrospective cross-sectional study of 181 CBCT scans was carried out. Using an implant-planning software, implant placement was simulated in the lingual aspect of the socket. The location of the prospective screw channel was registered as incisal, lingual, or facial. The angle between the actual screw channel and the position of the ideal one was calculated. The effect of angle correction on allowing an ideal screw channel configuration was computed. Out of 161 eligible cases, 144 presented favorable anatomy for an immediate implant. The screw channel had an incisal position in 40 cases (28%), a lingual position in 60 cases (42%), and a facial position in 44 cases (30%). The screw channel could be placed at the planned distance from the incisal edge in 35 cases (24%). The position was unfavorable in the remaining 109 cases. In 103 of these cases, an abutment with an angled screw channel could make the conditions feasible. Within the simulated conditions, a majority of maxillary central incisors present favorable ridge anatomy for lingualized immediate implant placement. Achieving a proper location of the screw channel requires abutments with angle correction in a majority of cases.
Seiten: 253-259, Sprache: Englisch
The aim of the present case series was to evaluate the outcomes of the modified coronally advanced tunnel technique (MCAT) using the width of keratinized tissue (KTW) as an indicator to apply the connective tissue graft (CTG) specifically. Seven patients requiring treatment for the presence of multiple gingival RT1 recession defects in the maxilla were enrolled in the study. A total of 36 recessions were treated with MCAT, and the CTG was applied in 16 sites presenting < 2 mm of KTW at baseline. The mean root coverage from baseline to 1 year postsurgery was 90% for the sites treated with MCAT alone and 93.7% for those treated with MCAT+CTG. The increase of KTW was higher in the sites treated with CTG than in the sites treated without it. Within the limitations of the present case series, it can be concluded that the proposed surgical technique is extremely effective in gaining root coverage and reducing the amount of connective tissue harvested from the donor site.
Seiten: 261-268, Sprache: Englisch
This study aimed to rehabilitate shortened maxillary dental arch with splinted crowns by connecting ultra-short implants with longer ones. In the posterior maxilla of 11 patients, one 10-mm (n = 11) and one or two ultra-short 4-mm (n = 17) dental implants were inserted. The insertion torque was lower than 20 Ncm in 55% of the 10-mm implants and in 94% of the 4-mm implants (P > .05). Median (range) implant stability quotients at the time of insertion and after 6 months were 61 (14 to 72) and 68 (51 to 79), respectively, for 4-mm implants, and 66 (52 to 78) and 78 (60 to 83), respectively, for 10-mm implants (P < .05). One 4-mm implant failed to integrate. All patients were restored with splinted metal-ceramic crowns connecting 4- and 10-mm implants. Median (range) clinical crown/implant ratios of 4-mm and 10-mm implants were 2.79 (1 to 3.66) and 1.06 (0.85 to 1.46), respectively (P < .05). Six months after prosthetic rehabilitation, the median (range) crestal bone loss was 0.3 mm (-0.7 to 1.7 mm) for 4-mm implants and was 0.5 mm (-0.8 to 3.5 mm) for 10-mm implants (P > .05). Splinted crowns combining 4- and 10-mm implants may contribute to a better force distribution in the treatment with ultra-short implant-supported prosthesis in the posterior maxilla.
Seiten: 269-275, Sprache: Englisch
The efficacy of the socket preservation procedure using deproteinized bovine bone mineral, bioabsorbable collagen membrane, and collagen sponge on molar extraction sites with severe periodontitis was assessed at 6 postoperative months, before implant placement. Results revealed excellent soft tissue healing without loss of keratinized tissue and no statistically significant differences in socket marginal bone changes in 20 molar extraction sockets. High levels of primary implant stability were recorded. Socket preservation using a minimally invasive surgical technique provides good soft and hard tissue healing as well as anticipated stability of implant placement at sites of extracted molars with severe periodontitis.
Seiten: 277-283, Sprache: Englisch
This study aimed to evaluate facial peri-implant tissue dimensions for implants connected to either convex or concave final abutments. Patients (n = 28) were randomly allocated to receive a single implant with an abutment of either convex (Group CX) or concave (Group CV) emergence shape. Twelve months after implant placement, CBCT scans were taken and reference points were identified: first visible bone-to-implant contact, implant shoulder (IS), bone crest (BC), and marginal mucosal level (MML). Mucosal thickness was evaluated at the level of IS (MT1), above the level of BC (MT2), and at the mid-distance of BC-MML (MT3). The mean total vertical peri-implant mucosa height was 3.26 ± 0.77 mm for Group CX and 3.70 ± 0.99 mm for Group CV (P = .23). The mean vertical peri-implant mucosa height below the bone crest was 0.62 ± 0.57 mm for Group CX and 1.26 ± 0.95 mm for Group CV (P = .04). Group CV had greater mean MT2 (4.09 ± 0.72 mm vs 3.36 ± 0.81 mm; P = .02) and MT3 (2.81 ± 0.66 mm vs 2.03 ± 0.60 mm; P = .005) compared to Group CX. Abutment macrodesign may have an effect on vertical and horizontal peri-implant tissue dimensions.
Seiten: 285-293, Sprache: Englisch
This randomized split-mouth preliminary clinical trial aimed to evaluate periodontal parameters and gingival blood flowmetry, comparing sites that received subepithelial connective tissue graft from the palate after deepithelialization (DE) or obtained with parallel incision (PI). Periodontal parameters were evaluated at baseline and 6 months postoperative. Gingival blood flows were analyzed by laser Doppler flowmetry (LDF) at baseline and 2, 7, and 14 days postoperative. Statistical and LDF analyses were performed with R version 3.5.1 and MATLAB software, and clinical parameters through ANOVA and Wilcoxon signed-rank tests. LDF showed superior decrease in power spectral density (PSD) for DE after 2 days. After 7 days, PSD returned to initial values only for PI, and DE had not returned to the initial values by day 14. Despite major initial revascularization challenges for DE sites, both grafts promoted satisfactory root coverage in the treatment of multiple gingival recessions.
Seiten: 295-301, Sprache: Englisch
Keratinized mucosa (KM) is regarded as a key factor in peri-implant health. A lack of KM has been associated with discomfort, higher plaque accumulation, and mucosal inflammation. Persistent inflammation might lead to progressive peri-implant bone loss. Several approaches to manage peri-implantitis have been advocated. Despite the effectiveness shown by surgical therapeutic modalities, soft tissue conditioning seems pivotal for long-term peri-implant health and stability. Free epithelial grafts have been demonstrated to efficiently augment the band of KM. Nevertheless, morbidity, dynamic soft tissue changes, and longer healing periods are shortcomings to be considered. The purpose of this technical note is to provide an alternative therapeutic modality for the surgical management of peri-implantitis combined with simultaneous soft tissue conditioning by means of pedicle flaps. Three main clinical scenarios are provided to conceive pedicle epithelial or connective tissue flaps, combined or not with collagen matrices, as predictable approaches to augment KM in the surgical therapy of peri-implantitis.
Online OnlySeiten: e27-e35, Sprache: Englisch
The purpose of this study was to evaluate vertical and horizontal alveolar resorption after the extraction of eight single maxillary molars using solvent-dehydrated bone allograft (Puros) covered with a nonresorbable membrane for ridge preservation. At implant placement 4 months later, ridge dimensions were measured clinically and radiographically and compared to baseline, and a histologic analysis was performed. The mean buccal height decreased by 1.51 mm at midpoint, 0.88 mm mesially, and 1.16 mm distally. The implants were placed without additional ridge augmentation, and six of eight required an internal sinus elevation. Within the limits of this study, this technique succeeded in preserving the alveolar bone.
Online OnlySeiten: e37-e44, Sprache: Englisch
Numerous surgical techniques for root coverage have been suggested with different degrees of success, as assessed by the proportion of complete root coverage. Mandibular incisors, teeth with a high frequency of gingival recession defects (GRDs), were associated with the least favorable outcomes due to unfavorable anatomical conditions. In the present series of three cases, a modified version of the free gingival graft technique for the purpose of root coverage at mandibular incisors is illustrated. The purpose of the modification of the original technique was to achieve improved blood supply from the recipient site to the graft, with the ultimate aim of enhancing predictability and outcomes of the procedure. In all included cases, complete or almost complete root coverage was achieved at challenging GRDs in the mandibular incisor area.
Online OnlySeiten: e45-e54, Sprache: Englisch
This study investigated the influence of silica-nylon reinforcement on the stress distribution and fracture load of a resin-bonded fixed partial dental prosthesis (RBFDP). Three-unit RBFDPs (N = 60) were inserted between the first premolar and the first molar of a maxillary model. The groups were divided according to the nylon reinforcement (n = 20/group): conventional fixed prosthesis (without reinforcement), prosthesis with silica-nylon reinforcement positioned vertically, and prosthesis with silica-nylon reinforcement positioned horizontally. Half of the specimens were tested after 24 hours in a universal testing machine until fracture (1,000 kgf; 1 mm/minute) to determine the single load to fracture. The other half was submitted to mechanical aging during 106 cycles (100 N, 2 Hz), totaling 6 groups (n = 10/group). The results were analyzed by two-way analysis of variance (ANOVA) (α = 5%). The stress distribution for non-aged groups was simulated using finite element analysis. The numeric prostheses were modeled similarly to the in vitro assay. ANOVA showed no statistical difference between groups (P < .05) for load to fracture. However, the use of the reinforcement provided stability even after the failure, as the parts did not separate. The computational analysis showed similar biomechanical behavior among the groups. The use of the nylon reinforcement does not influence the fracture load or the stress distribution, but it does enable the prosthesis to remain in position after failure.
Online OnlySeiten: e55-e62, Sprache: Englisch
This study evaluated the accuracy of implant placement with surgical-template guidance both in vitro and in vivo. Virtual surgical planning was performed based on the data from CBCT scans and an intraoral scanner. Surgical templates were designed according to the planned implants and manufactured with stereolithography. In vitro, 60 implants were placed in 15 resin models. In vivo, 74 implants were placed in 54 patients. The implants were scanned with CBCT postoperatively. Implant accuracy was evaluated by measuring the following parameters: central deviation at the apex and shoulder, horizontal deviation at the apex and shoulder, vertical deviation at the apex and shoulder, and angular deviation. There were statistically significant in vitro and in vivo deviations for all parameters, and the implant deviations in vivo were significantly greater than those in vitro. When using a mucosa-supported template, horizontal deviations at the apex were significantly greater than when a teeth-supported template was used. Within the limitation of the study design, inaccuracy existed in implant placement guided with a surgical template. More studies are needed to investigate the value of the procedure in future.
Online OnlySeiten: e63-e71, Sprache: Englisch
This randomized controlled clinical trial with a 1-year follow-up evaluated gingival thickness changes around teeth after use of dermal allograft and xenograft matrix. A total of 116 teeth (19 patients) were separated into two groups. One group received xenogeneic collagen matrix (n = 48), while the other received allogeneic acellular dermal matrix (n = 68) via a coronally advanced flap (CAF). Gingival thickness (GT), keratinized gingival width (KGW), pocket depth (PD), and clinical attachment loss (CAL) were measured on the day of surgery (baseline) and at 3 weeks, 2 months, 6 months, and 1 year postoperative. The two groups were compared using repeated-measures ANOVA (P < .05). The mean GT at 1 year was 1.59 ± 0.31 mm in the xenogeneic group and 1.63 ± 0.33 mm in the allogeneic group (P = .60). The mean change in GT was 1.08 mm in the xenogeneic group and 1.13 mm in the allogeneic group, which was clinically relevant and statistically significant compared to baseline values (P < .001). However, changes in GT were not significantly different between the two groups at any time point (P > .05). The GT increased in all cases treated with allogeneic and xenogeneic enriched collagen matrix. Both soft tissue substitutes were equally effective in acheiving optimal GT.