International Journal of Periodontics & Restorative Dentistry, 04/2021

This study describes a clinical strategy based on a flowchart developed to facilitate the treatment of teeth with a severely compromised clinical crown. A group of 168 teeth in 126 patients required periodontal surgery and received a minimally invasive crown-lengthening procedure with the aim to reach a minimal supracrestal tissue attachment width of 2.5 mm, including a free space between the cervical margin of the restoration and the bottom of the sulcus. Surgery was performed with the aid of an operating microscope and microsurgical instruments, trying to reduce bone surgery and invasiveness as much as possible. An average postsurgical radiographic bone resection of 1 ± 0.6 mm was measured. Endodontic treatment was necessary in 73 teeth, re-treatment in 51. Most of the teeth (124 in 94 patients) received a full crown, while the remaining 44 received a direct (24 teeth) or an indirect (20 teeth) reconstruction. Six teeth were orthodontically extruded before surgery. The 1-year average pocket depth at the treated units was 2.5 ± 0.5 mm, resulting in a reduction of 0.7 ± 0.9 mm compared to the preoperative measurement (P < .0001). Bleeding on probing was detected in 19 sites (11.3%) and was significantly reduced from the preoperative condition (57 sites, 33.9%). The distance between the apical margin of the restoration and the gingival margin was 0.2 ± 0.4 mm (range: 0 to 1 mm); clinical attachment level was 2.7 ± 0.6 mm. A clinical approach based on minimally invasive crown lengthening with minimal or no ostectomy and high-quality restorative dentistry resulted in healthy periodontal and dental condition of all the treated units at the 1-year follow-up.

A novel macro-hybrid implant design was introduced to afford high apical primary stability and more coronal space to preserve the circumferential extraction socket architecture. This study presents 1-year data from a prospective single-arm cohort study. The data was distilled based on the following criteria: (1) single-tooth immediate tooth replacement therapy (ITRT) in the maxillary anterior and premolar regions in intact (Type 1) extraction sockets that were (2) treated with the dual-zone grafting technique. The clinical and radiographic outcomes of 48 ITRT implants were evaluated. The mean ± SD labial plate dimension changes were 0.33 ± 0.41 mm at the implant abutment interface (L1) and 0.34 ± 0.40 mm at 5.0 mm below (L2). The mean labial plate dimension (thickness) at the 1-year recall was 2.27 ± 0.88 mm (L1) and 1.95 ± 0.95 mm (L2). At ITRT, the ridge contour at the free gingival margin and 3.0 mm below it were 7.54 ± 0.93 mm and 9.44 ± 2.36 mm, respectively; after final restoration delivery, the corresponding values were 7.45 ± 0.95 mm and 10.23 ± 2.30 mm, respectively. The peri-implant soft tissue thickness (PISTT) at the time of implant-level impression-making was 3.29 ± 0.73 mm, with an average Pink Esthetic Score of 12.79. A macro-hybrid implant design showed high levels of primary stability (~60 Ncm), stable ridge contour at 1 year, a labial plate dimension between 1.5 and 2.0 mm, and PISTT > 3.0 mm, which may be a critical factor in providing stable, long-term esthetic outcomes.

The aim of this classification is to diagnose and grade four different types of soft tissue deficiency around loaded, osseointegrated implants according to increasing severity. The suggested soft tissue augmentation to increase the width of the peri-implant keratinized mucosa will improve the long-term stability of peri-implant tissues.

This multicenter retrospective study assessed clinical and radiographic outcomes of 686 parallel-walled conical-connection implants consecutively placed in 281 partially and fully edentulous patients. Implants were placed in healed and postextraction sites and subjected to immediate, early, or delayed loading. With a mean follow-up of 10 ± 6.7 months, the implant survival rate was 97.7%, while mean marginal bone loss was 0.7 ± 1.5 mm between implant placement and 1 year (n = 290 implants) and 0.1 ± 0.6 mm between 1 and 2 years (n = 72 implants). Advanced patient age and longer implants were associated with fewer implant failures, while different crestal positions at implant placement were not associated with differences in implant survival or changes in marginal bone level over time.

Minimally invasive microsurgery performed using an operating microscope (OM) has shown accelerated and improved wound healing for periodontal plastic and regenerative procedures. This case series aims to demonstrate the potential usefulness of OM for maxillary sinus augmentation in a private practice setting. Twelve vertical sinus augmentations (VSAs) and 8 lateral sinus augmentations (LSAs) were performed with the assistance of OM. Flap reflection, osteotomy, sinus membrane elevation, membrane integrity evaluation, implant placement (if indicated), and wound approximation with sutures were performed under OM. After a minimum healing period of 6 months, radiographic bone height gain was assessed. One sinus membrane perforation was observed during VSA surgery. The mean vertical bone gain was 4.82 ± 1.31 mm and 8.36 ± 1.45 mm for VSA and LSA, respectively, with 100% implant success rate. OM-assisted maxillary sinus augmentation provides favorable clinical visualization, thus facilitating delicate hard and soft tissue manipulation.

Bone exostosis is defined as a benign overgrowth of bone tissue of unclear origin. Rarely, bone exostosis might develop following soft tissue graft procedures like mucogingival surgical interventions (eg, FGG or subepithelial CTG). This aberration has been mainly associated with surgical trauma or fenestration of the periosteum but is still a matter of debate. The present paper (1) presents a clinical case with clinical, radiographic, and histologic findings at 30 years following application of an FGG to increase the gingival width and (2) provides a short literature review on this particular clinical condition. At the clinical examination, the FGG was firm to palpation, and the 3D images showed an area of increased radiopacity. Histologic analysis revealed localized thickening of the bone with an overlaying connective tissue covered by keratinized epithelium. The bony tissue was vital, had a convex shape, and contained many osteocytes and resting lines, demonstrating some moderate signs of bone remodeling. The connective tissue and keratinized epithelium displayed a regular thickness without any signs of inflammation. Taken together, the histologic findings failed to reveal any pathologic signs except for the presence of vital bone formed outside the bony envelope. It can be concluded that: (1) the development of a bone exostosis following a mucogingival procedure is a rare clinical sequela of uncertain etiology, and (2) surgical removal of the exostosis may be indicated accordingly with patient symptoms.

The purpose of this randomized clinical study was to evaluate the efficacy of platform-switching (PS) vs platform-matching (PM) implants when paired with a newly designed marginless abutment (MA) vs a conventional abutment (CA) in maintaining peri-implant tissue stability. Marginal bone level (MBL) and probing depth were measured up to 1 year postloading. Eighty implants were inserted in 42 patients and randomly assigned to one of four groups, each with a different implant/abutment configuration: Group 1 (PM+CA), Group 2 (PM+MA), Group 3 (PS+CA), and Group 4 (PS+MA). Data were collected at implant placement (T0), abutment placement (T1), final crown placement (T2), and 1 year postloading (T3). At the 1-year follow-up, MBL was more stable in Groups 3 and 4 compared to Groups 1 and 2. These results suggest that the role played by the implant-abutment connection (PS vs PM) is more important than the type of abutment preparation (MA vs CA).

Passive-tension flap closure of primary wounds remains the most important factor for achieving predictable bone augmentation outcomes. So far, no specific surgical technique has been proposed for major flap advancement, specifically in the thin tissue phenotype (≤ 1.5 mm thick). This article illustrates a detailed description of the Mucosal Detachment Technique (MDT), which separates the mucosal tissue from the underneath periosteum and aims to achieve adequate flap flexibility to cover high-volume augmentation in the thin tissue phenotype. Separating the mucosa from the periosteum allows maintenance of vascularization and an even distribution of tension among the advanced flap. The MDT allows bone augmentation procedures in thin tissue phenotype flap. The flap advancement permits tension-free primary closure in all tissue phenotypes (both thin and thick), independent of the degree of volume augmentation.

The purpose of this 12-month randomized, controlled clinical trial was to evaluate the efficacy of a monotherapy protocol with the neodymium-doped yttrium aluminum garnet (Nd:YAG) laser for treatment of peri-implantitis. Twenty patients with 36 implants exhibiting probing pocket depths (PPDs) > 4 mm and evidence of radiographic bone loss (RBL) were randomly divided into two groups. The test group was treated with the Nd:YAG laser, and the control group was managed with mechanical debridement only. Peri-implant clinical parameters were recorded at baseline and at 12 months after treatment. PPD, RBL, and bleeding on probing showed improvements after 12 months in the test and control groups. The laser therapy provided additional benefits of greater reduction in PPDs and increased bone level with no adverse outcomes. The results demonstrated that laser therapy could be a valuable modality for the treatment of peri-implantitis.

This study aimed to evaluate the correlation between soft tissue thickness measured by CBCT and phenotype probing estimation and to assess the thickness cutoffs for each phenotype probing outcome. CBCT was performed with a lip retractor in order to isolate periodontal soft tissues in 10 consecutive patients. Using colored probes, the phenotype was evaluated for all present teeth and recorded as thin, medium, thick, or very thick. The overall correlation between tissue thickness and the phenotype probe score was r = 0.86 (CI: 0.80, 0.90). The correlation was r = 0.90 (CI: 0.81, 0.94) when only maxillary anterior teeth were considered. The obtained cutoffs were 0.83 mm between thin and medium phenotypes, 1.07 mm between medium and thick phenotypes, and 1.24 mm between thick and very thick phenotypes. Thus, a high correlation between tissue thickness and the phenotype probe score was found. Preliminary data on the use of phenotype probes as an evaluation method for gingival thickness were promising.

The aim of this histomorphometric study was to compare the outcome of sinus floor augmentation procedures using bovine bone mineral and a xenograft enriched with gelatin and a polymer. In 20 patients a single sinus floor elevation procedure with a lateral window approach was performed. In half of the patients, sinuses were grafted with a deproteinized bovine bone mineral-DBBM (control group)-while in the remaining 10, a xenograft enriched by polymer and gelatin-NBS (test group)-was applied. In the DBBM group, histomorphometric analysis revealed 23.14 ± 10.62% of lamellar bone, 19.43% ± 9.18% of woven bone, 23.35% ± 6.04% of osteoid, 17.16% ± 6.13% of biomaterial particles, and 16.93% ± 9.78% of medullary spaces. In the NBS group, histomorphometric analysis found 39.64% ± 12.02% of lamellar bone, 16.28% ± 7.75% of woven bone, 17.51% ± 4.87% of osteoid, 12.72% ± 5.36% of biomaterial particles, and 13.84% ± 6.53% of medullary spaces. Differences between groups for proportion of lamellar bone (P = .004) and osteoid (P = .0287) were statistically significant. Inflammatory infiltration was appreciated only in the NBS group. The enriched xenograft showed a statistically significant higher proportion of lamellar bone and osteoid; however, this was accompanied by an accentuated inflammatory infiltrate.

This study assessed the levels of tumor necrosis factor-α (TNF-α), prostaglandin E2 (PGE2), receptor activator of nuclear factor kappa B (RANK), RANK ligand (RANKL), osteoprotegerin (OPG), and levels of Fusobacterium nucleatum, Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia, Prevotella intermedia, and Streptococcus oralis in areas where airborne particle-abraded, large-grit, acid-etched (SLA), fluorine-modified, and anodized implant surfaces are used. A total of 71 implants from 37 patients were assessed, grouped according to the surface characteristics of the implants: SLA surface (Group 1), fluorine-modified surface (Group 2), and anodized surface (Group 3). The following clinical indices were measured: Gingival Index (GI), probing depth (PD), bleeding on probing (BOP), clinical attachment level (CAL), and keratinized tissue width (KTW). Peri-implant sulcus fluid and subgingival plaque samples were also collected. Commercial enzyme-linked immunosorbent assay (ELISA) kits were purchased for measuring TNF-α, PGE2, RANKL, RANK, and OPG. Real-time quantitative polymerase chain reaction (PCR) was used to detect P intermedia, T forsythia, T denticola, F nucleatum, P gingivalis, and S oralis levels in the subgingival biofilms. The groups showed no statistically significant differences in GI, PD, BOP, CAL, KTW, or peri-implant status. The total amounts of PGE2, TNF-α, RANKL, RANK, and OPG and the RANKL/OPG ratio were not significantly different between groups. F nucleatum, T forsythia, P intermedia, P gingivalis, and T denticola were significantly higher in Group 3 implants. DNA concentrations of S oralis were higher in Group 2. Within the limitations of this study, SLA and fluorine-modified implant surfaces may be more clinically successful than anodized-surface implants.

Gingival recession accounts for apical migration of the gingival margin, resulting in exposure of the cementoenamel junction and root surface, with exposure of the root surface linked to deteriorated esthetic appearance and increased dentinal hypersensitivity. Various surgical techniques have been used to correct labial gingival recession defects. The present study evaluated and compared the results of semilunar coronally positioned flap (SCPF) alone and in conjunction with free gingival graft (FGG) for the treatment of Miller Class I and II gingival recession defects in maxillary anterior teeth. A total of 20 bilateral Miller Class I and II gingival recession sites were included and randomly allocated (n = 10 sites/group) to either the semilunar coronally positioned flap technique alone (SCPF group; control) or with FGG (SCPF+FGG group; test). Longitudinal alterations in probing depth (PD), recession width (RW), recession height (RH), width of keratinized tissue (WKT), and clinical attachment level (CAL) were measured and analyzed for both groups at 1-, 3-, 6-, and 12-month follow-ups. Both groups saw a significant decrease in RH, RW, and CAL and a significant increase in WKT. No statistically significant difference was observed in the final root coverage outcome between both groups in terms of RH, RW, and CAL, but a significant increase in WKT was seen with SCPF+FGG. Both techniques demonstrated optimal results without significant differences in the final root coverage outcomes except for WKT, which had a statistically significant increase in the SCPF+FGG group.

The correction of transverse malocclusions due to maxillary width deficiency in adults is challenging. Multiple surgical and nonsurgical procedures have been used in conjunction with orthodontics to address this situation, and most common is the surgically assisted rapid maxillary expansion (SA-RME). Although successful, it is quite aggressive. The present investigation assesses the usefulness of Piezocision-assisted orthodontics as a less-invasive option for treatment of transverse maxillary deficiencies in adults. Dental casts were taken before and after Piezocision-assisted palatal expansion in four patients. They were digitized into STL files and superimposed. Differences on cross-arch tooth torque, angulation/tipping, and movement distances between time points were quantified using a digital static and a novel digital 3D-movement evaluation method. For the buccolingual movement per tooth, first premolars averaged 3.33 ± 1.3 mm, second premolars averaged 3.63 ± 0.6 mm, and first and second molars averaged 1.56 ± 1.2 mm and 0.36 ± 1.2 mm, respectively. Bodily movement of the teeth was observed with minimal tipping and no development of gingival recessions. Piezocision-assisted palatal expansion is a safe and reliable procedure that can help patients with maxillary width deficiency. It is a new tool in the orthodontist's armamentarium that can be used as an accelerator of treatment and as a new way to solve orthodontic challenges in selected adult patients.

Inferior alveolar nerve (IAN) damage following implant placement is a severe complication that can compromise a patient's quality of life. Previous studies have suggested that a safety zone of 2 mm, if maintained, might avoid this problem. This retrospective study evaluates implants placed in closer proximity to the IAN without resulting in any postoperative neurologic complications and suggests a new concept of safety distance. A total of 60 consecutive patients receiving 101 mandibular implants < 2 mm from the IAN were included in this study. All enrolled patients had a CBCT scan done for radiologic assessment before implant placement and following final restoration. Measurements were obtained through cross-sectional views using Simplant software. In patients without neurologic disturbances, a mean distance of +0.75 mm was seen from the closest portion of the implant to the nerve bundle. In cases where a direct transection and/or compression of the nerve was not observed, the patients did not experience neurosensory disturbances.

The aim of this study was to analyze horizontal bone augmentation using the tenting screw technique in the posterior mandible. Included subjects had a 3-mm bone width and 9-mm bone height, measured by CBCT. After the surgical approach, two to four screws were inserted, leaving 4 mm of extraosseous space; reconstruction was achieved using allogeneic biomaterial and leukocyte- and platelet-rich fibrin together with an absorbable membrane. After 4 months, a new CBCT scan was obtained to compare the bone gain and implant placement. Early and secondary stability were measured by the implant stability quotient (ISQ); prosthetic load was performed 16 weeks later. Student t test was used to compare bone gains and implant stability, with significance set at P < .05. Fourteen subjects and 27 surgical sites initially exhibited a mean bone width of 2.95 ± 0.75 mm. Four months after augmentation, the bone width was 7.15 ± 1.87 mm, confirming a significant bone gain (4.2 ± 1.26 mm). Twenty-seven implants were placed with a minimum insertion torque of 35 Ncm; the primary stability was 69.3 ± 7.16 ISQ, and the secondary stability was 75.9 ± 3.29 ISQ (P > .05). It may be concluded that the tenting screw technique is predictable in terms of bone gain and that it facilitates implant stability.

Using autogenous grafts in mucogingival surgeries is related to postoperative morbidity and limited tissue availability, and thus xenogeneic matrices are increasingly used. This in vitro study evaluated the influence of xenogeneic collagen matrix thickness on cell adhesion, morphology, viability, proliferation, and matrix degradation. Matrices were divided into three groups: SLC: single layer of Lumina Coat, as commercially available (2-mm thickness); DLC: double layer of SLC (Lumina Coat); and MG: single layer of Mucograft, as commercially available (4-mm thickness). SEM was used to evaluate the matrix surface topographies. To evaluate the cell viability, proliferation, adhesion, and morphology, human gingival fibroblasts (HGF) and stem cells from human exfoliated deciduous teeth (SHED) were used. Cell viability was evaluated through MTS colorimetric method evaluating HGF and SHED on days 1, 3, and 7. Cell proliferation was assessed by PicoGreen assay, evaluating HGF and SHED on days 3 and 7. Sample degradation was evaluated on days 1, 3, 7, 14, 21, 28, and 35. All groups were biocompatible for HGF and SHED, showing viabilities > 70% on days 1, 3, and 7. DCL promoted HGF viabilities similar to MG (P = .2828) and the highest SHED viability (P < .0001) on day 1. DLC also demonstrated HGF and SHED proliferations higher than the positive control (MG; P < .05) on day 7. SLC was completely degraded on day 14, while DLC and MG presented 48.41% and 20.52% of their initial mass, respectively, on day 35. Increasing the matrix thickness improved HGF and SHED viability and proliferation and prevented early matrix degradation. DLC demonstrated better results than SLC and MG concerning matrix degradation and HGF and SHED viability and proliferation.

In order to achieve favorable ridge preservation (RP) or ridge augmentation (RA) in substantial vertical and/or horizontal bone defects and extraction sockets, a barrier membrane is usually employed. Recently, it was reported that a novel surgical technique for periodontal regenerative surgery applying Er:YAG laser (ErL) irradiation to form blood coagulation on the grafted bone surface, without using a membrane, resulted in sufficient bone regeneration in bone defects. This case series aims to present clinical and radiographic outcomes of ErL-assisted bone regenerative therapy (Er-LBRT), without use of membranes, for RP/RA before or after implant placement. In 10 cases, ErL irradiation was applied (50 mJ/pulse and 20 Hz without water spray in noncontact, defocused mode for approximately 60 seconds) to enhance the blood clot on the entire surface of the grafted bovine bone mineral before suturing. Wound healing was favorable without any postoperative complications such as wound gaping or infection of the grafted material. In all cases, dramatic bone regeneration was observed. After prosthetic treatment, peri-implant tissue and regenerated bone were stable and well-maintained during the follow-up period in each case. This novel technique of Er-LBRT without using a membrane resulted in favorable and stable RP/RA with sufficient bone regeneration for implant therapy.

In the maxillary anterior region, augmentation to correct a soft tissue deficiency is often required for an esthetic outcome and long-term implant therapy success. This case series of three patients presents a novel approach for soft tissue augmentation using xenogeneic collagen matrix balls in the esthetic zone around the implants. This technique avoids a secondary donor site compared to autogenous connective tissue graft. With this technique, a horizontal soft tissue volume increase (range: 3 to 5 mm) was observed postsurgically and maintained at later follow-ups. The described ball technique offers a viable method for peri-implant mucosal augmentation in the maxillary anterior region.

This report presents a case in which autogenous bone grafts were harvested from the maxillary tuberosity for guided bone regeneration and dental implant placement, with long-term follow-ups and assessment at the clinical, tomographic, and histologic levels. Particulate and block autogenous bone grafts were covered with a resorbable collagen membrane. Advanced bone remodeling and good bone quality, enabling dental implant placement, were observed after a short healing time (3 months). The differences in buccal bone plate thickness in the grafted area between the period immediately after implant placement and 4 years thereafter ranged from +0.879 mm to -0.001 mm. The implants osseointegrated uneventfully, and alveolar bone regeneration remained stable with a satisfactory result after 4 years.