Associations between the keratinized mucosa width and the underlying alveolar bone dimensions at partial edentulous molar sites: a retrospective cross-sectional study

BACKGROUND

The assessment of hard and soft tissue at edentulous sites is important for subsequent implant treatment design. The aim of the present study was to explore the associations between the keratinized mucosa width (KMW) and the underlying alveolar bone dimensions at partial edentulous molar sites.

METHODS

In this retrospective study, a total of 110 patients with at least one missing molar were selected. The buccal KMW of the edentulous molar sites was evaluated. Cone-beam computed tomography scans were collected, and the height discrepancy between the alveolar crest and the buccal bone plate (HC-B) as well as the alveolar bone height (ABH) were measured. The KMW was compared among the HC-B and ABH groups at both maxillary and mandibular sites. Linear regression and generalized estimation equations (GEEs) were used to explore the associations between the KMW and alveolar bone dimensions at α = 0.05.

RESULTS

Among the 110 patients, 158 edentulous molar sites were analyzed. The average HC-B and ABH were significantly lower at the maxillary sites (1.26 ± 1.62 mm, 11.62 ± 3.94 mm) than at the mandibular sites (3.67 ± 2.85 mm, 14.91 ± 3.01 mm, p < 0.001). The KMW was significantly lower at sites with HC-B > 2 mm than at sites with HC-B ≤ 2 mm both in the maxilla and mandible (p < 0.001). No significant differences were found between the KMW at sites with ABH < 10 mm and sites with ABH ≥ 10 mm (p > 0.05). Linear regression and GEEs analyses revealed that the HC-B was significantly associated with the KMW (B = -0.339, p < 0.001), while the association between the KMW and the ABH was not statistically significant (B = -0.046, p = 0.352).

CONCLUSIONS

The buccal KMW at edentulous molar sites was significantly associated with the HC-B. Alveolar ridges presenting with a sloped configuration were more prone to possess a narrower band of keratinized mucosa. Both hard and soft tissue augmentation should be considered for implant treatment at these sites. The correlations of dynamic changes between the KMW and alveolar bone dimensions after tooth extraction should be further investigated.

Performance of a multiphase bioactive socket plug with a barrier function for alveolar ridge preservation

The natural healing process of extraction socket and traditional socket plug material could not prevent buccal bone wall resorption and down growth of epithelium from the socket orifice. A multiphase bioactive socket plug (BP) is designed to overcome the natural healing process by maintaining the three-dimensional (3D) volume of extraction sockets, particularly in sockets with wall defects, and later provide sufficient alveolar bone volume for implant placement. The study aimed to fabricate and evaluate the physical, chemical, and biological performance of BPin vitro. The BP was fabricated through freeze-drying and layer-by-layer assembly, comprised of a base serving as a scaffold, a central portion for promoting bone regeneration, an upper buccal portion for maintaining alveolar socket dimension with a covering collagen membrane (Memb) on the top and upper buccal surface to prevent soft tissue infiltration. The BP as the experimental group and a pure collagen plug (CP) as the control group were investigated and compared. Radiograph, scanning electron microscopy, and energy-dispersive spectroscopy mapping confirmed that the four-part BP was successfully assembled and fabricated. Swelling rate analysis indicated that BP, CP, and Memb reached swelling equilibrium within 1 hour. BP exhibited a high remaining weight percentage in collagenase solution (68.81 ± 2.21% on day 90) and sustained calcium ion release, reaching the maximum 0.13 ± 0.04 mmol l-1on day 14. In biological assays, BP exhibited excellent cell proliferation (The OD value increased from 0.02 on day 1 to 0.23 on day 21.). The BP group exhibited higher alkaline phosphatase activity and osteocalcin content than the CP group within 21 days. Memb and BP exhibited outstanding barrier function, as evidenced by Hematoxylin and eosin staining. In summary, the multiphase bioactive socket plug represents a promising scaffold for alveolar ridge preservation application.

Alveolar Ridge Preservation Using a Novel Species-Specific Collagen-Enriched Deproteinized Bovine Bone Mineral: Histological Evaluation of a Prospective Case Series

In recent years, the significance of maintaining the alveolar ridge following tooth extractions has markedly increased. Alveolar ridge preservation (ARP) is a commonly utilized technique and a variety of bone substitute materials and biologics are applied in different combinations. For this purpose, a histological evaluation and the clinical necessity of subsequent guided bone regeneration (GBR) in delayed implantations were investigated in a prospective case series after ARP with a novel deproteinized bovine bone material (95%) in combination with a species-specific collagen (5%) (C-DBBM). Notably, block-form bone substitutes without porcine collagen are limited, and moreover, the availability of histological data on this material remains limited. Ten patients, each scheduled for tooth extraction and desiring future implantation, were included in this study. Following tooth extraction, ARP was performed using a block form of C-DBBM in conjunction with a double-folded bovine cross-linked collagen membrane (xCM). This membrane was openly exposed to the oral cavity and secured using a crisscross suture. After a healing period ranging from 130 to 319 days, guided trephine drilling was performed for implant insertion utilizing static computer-aided implant surgery (s-CAIS). Cores harvested from the area previously treated with ARP were histologically processed and examined. Guided bone regeneration (GBR) was not necessary for any of the implantations. Histological examination revealed the development of a lattice of cancellous bone trabeculae through appositional membranous osteogenesis at various stages surrounding C-DBBM granules as well as larger spongy or compact ossicles with minimal remnants. The clinical follow-up period ranged from 2.5 to 4.5 years, during which no biological or technical complications occurred. Within the limitations of this prospective case series, it can be concluded that ARP using this novel C-DBBM in combination with a bovine xCM could be a treatment option to avoid the need for subsequent GBR in delayed implantations with the opportunity of a bovine species-specific biomaterial chain.

Timing implant provisionalization: Decision-making and systematic workflow

OBJECTIVE

Provisionalization is an important step to achieve esthetic results in implant cases, and many different techniques for provisional restoration fabrication have been described. However, depending on the clinical scenario, the provisionalization strategy will require different approaches and timing. The clinician should modify the provisional restorations efficiently to reduce the number of disconnections from the implant, as repeated disconnections may have biological consequences. This article aims to schematize different scenarios requiring implant provisionalization and propose strategies to help the clinician condition the peri-implant tissues, respecting perio-prosthodontic fundamentals for soft tissue, biological, and esthetic stability.

CLINICAL CONSIDERATIONS

The clinical outcomes of modern implant therapy aim to achieve results that emulate natural dentition. Different scenarios may require adjunct therapy, including hard- and soft-tissue grafting, which complicates treatment. The provisionalization strategy will vary depending on the initial condition of the tissues, the need for reconstructive procedures, and the timing of implant placement. Selecting the right strategy based on the case type is necessary to reduce treatment time and complications associated with inadequate prosthetic handling of the soft tissues.

CLINICAL SIGNIFICANCE

Proper emergence profile conditioning through provisional restorations will allow for biologically sound and esthetically pleasing outcomes in implant restorations.

Influence of freeze-dried bone allograft on free gingival graft survival and alveolar ridge maintenance in socket seal procedures: a randomized controlled clinical trial

PURPOSE

This study aimed to investigate the viability of free gingival grafts (FGG) and assess clinical and radiographic changes in the alveolar ridge following socket seal surgery with or without freeze-dried bone allograft (FDBA).

MATERIALS AND METHODS

Twenty-eight anterior and premolar tooth extractions were randomly allocated to 2 groups: socket graft of FDBA sealed with FGG (n = 15) and control with empty sockets sealed solely with FGG (n = 13). Photographs taken at 3, 7, 14, and 30 days post-surgery assessed FGG viability. Alveolar ridge volume was clinically evaluated via intraoral scanners before surgery and at 1 and 3 months post-surgery. CBCT scans taken immediately post-surgery and 3 months later assessed alveolar ridge dimensions.

RESULTS

FGG viability in both groups increased from day 3 and reached the maximum score on day 14. Alveolar ridge volume reduction at 3 months in the FDBA group was comparable to the control group. Buccal alveolar bone height reduction was significantly higher in the FDBA group than the control group, while palatal alveolar bone height was comparable. Alveolar bone width reduction was evident but not statistically significant between the groups. The FDBA group exhibited a significant alteration in bone volume compared to the control group.

CONCLUSION

Viability of FGG was not affected by graft filling materials. Sealing the socket with FGG effectively preserved socket integrity and ridge volume in minor socket defects using either graft filling material or not. This study was registered on 4 January 2021 on Thai Clinical Trials Registry (TCTR20210104001).

Early implant placement in sites with ridge preservation or spontaneous healing: histologic, profilometric, and CBCT analyses of an exploratory RCT

PURPOSE

The aim of this study was to compare changes in soft and hard tissue and the histologic composition following early implant placement in sites with alveolar ridge preservation or spontaneous healing (SH), as well as implant performance up to 1 year after crown insertion.

METHODS

Thirty-five patients with either intact buccal bone plates or dehiscence of up to 50% following single-tooth extraction of incisors, canines, or premolars were included in the study. They were randomly assigned to undergo one of three procedures: deproteinized bovine bone mineral with 10% collagen (DBBM-C) covered by a collagen matrix (DBBM-C/CM), DBBM-C alone, or SH. At 8 weeks, implant placement was carried out, and cone-beam computed tomography scans and impressions were obtained for profilometric analysis. Patients were followed up after the final crown insertion and again at 1 year post-procedure.

RESULTS

Within the first 8 weeks following tooth extraction, the median height of the buccal soft tissue contour changed by -2.11 mm for the DBBM-C/CM group, -1.62 mm for the DBBM-C group, and -1.93 mm for the SH group. The corresponding height of the buccal mineralized tissue changed by -0.27 mm for the DBBM-C/CM group, -2.73 mm for the DBBM-C group, and -1.48 mm for the SH group. The median contour changes between crown insertion and 1 year were -0.19 mm in the DBBM-C/CM group, -0.09 mm in the DBBM-C group, and -0.29 mm in the SH group.

CONCLUSIONS

Major vertical and horizontal ridge contour changes occurred, irrespective of the treatment modality, up to 8 weeks following tooth extraction. The DBBM-C/CM preserved more mineralized tissue throughout this period, despite a substantial reduction in the overall contour. All 3 protocols led to stable tissues for up to 1 year.

Alveolar ridge changes 1-year after early implant placement, with or without alveolar ridge preservation at single-implant sites in the aesthetic region: A secondary analysis of radiographic and profilometric outcomes from a randomized controlled trial

OBJECTIVES

To assess both the radiographic and profilometric outcomes of early implant placement with or without alveolar ridge preservation (ARP) (using two different ARP techniques) after 1 year of loading.

MATERIALS AND METHODS

Seventy-five patients with a failing single tooth in the anterior maxilla were randomly allocated to three groups (1:1:1): (a) ARP using demineralized bovine bone mineral containing 10% collagen (DBBM-C) covered by a collagen matrix (CM), (b) ARP using DBBM-C covered with a palatal graft (PG), and (c) unassisted socket healing (control). Eight weeks after tooth extraction, early implant placement was performed in all patients. Cone-beam computed tomography (CBCT) and impressions were taken 8 weeks after tooth extraction (ARP/unassisted healing) prior to implant placement and 1-year post-loading. Radiographic and profilometric outcomes were evaluated.

RESULTS

Out of the 70 patients available for re-examination at 1-year post-loading, 55 datasets could be assessed (ARP-CM 19; ARP-PG 17; Control 19). The need for additional guided bone regeneration (GBR) at implant placement amounted to 31.6% (ARP-CM), 29.4% (ARP-PG), and 68.4% (unassisted healing). Adjusted models revealed that residual buccal bone height and additional GBR at implant placement significantly influenced the magnitude of the alveolar changes at 1 year (p < 0.05). In patients with ARP (group ARP-CM or ARP-PG) without additional GBR, the presence of bone convexity amounted to 36.0% (9/25) at 1-year post-loading. For patients that received ARP and additional GBR at implant placement, the frequency of bone convexity increased to 72.7% (8/11) (p = 0.042). Regarding profilometric measurements, a tendency toward agreement with radiographic outcomes was observed.

CONCLUSIONS

Early implant placement with ARP can attenuate alveolar ridge changes at 1-year post loading by minimizing both radiographic and profilometric alterations. However, early implant placement with simultaneous GBR consistently yields superior radiographic and profilometric outcomes, regardless of whether ARP is performed.

Carbonate apatite increases gene expression of osterix and bone morphogenetic protein 2 in the alveolar ridge after socket grafting

PURPOSE

After tooth extraction, preservation of the alveolar ridge by socket grafting attenuates bone resorption. Runt-related transcription factor 2 (RUNX2) and SP7/Osterix (OSX) are transcription factors playing an important role in osteoblast differentiation. The purpose of this study was to evaluate the effects of carbonate apatite (CO3Ap) on osteoblast-related gene and protein expression after socket grafting.

METHODS

Alveolar bone and new bone after CO3Ap grafting were collected at the time of implant placement. Levels of mRNA for RUNX2, SP7/OSX, bone morphogenetic protein 2 (BMP2), BMP7 and platelet derived growth factor B were determined by real-time PCR. Immunostaining was performed using antibodies against RUNX2, SP7/OSX, vimentin and cytokeratin. To evaluate bone resorption rates, cone-beam CT (CBCT) imaging was performed after socket grafting and before implant placement.

RESULTS

CBCT imaging showed that the average degree of bone resorption at the CO3Ap graft site was 7.15 ± 3.79%. At the graft sites, levels of SP7/OSX and BMP2 mRNA were significantly increased. Replacement of CO3Ap with osteoid was evident histologically, and in the osteoid osteoblast-like cells were stained for SP7/OSX and vimentin.

CONCLUSION

These results show that gene expression of both SP7/OSX and BMP2 can be induced by CO3Ap, suggesting that increased expression of SP7/OSX and vimentin may be involved in the BMP pathway.

Efficacy of Autogenous Dentin Biomaterial on Alveolar Ridge Preservation: A Randomized Controlled Clinical Trial

Background

After tooth extraction, alveolar bone resorption is inevitable. This clinical phenomenon challenges dental surgeons aiming to restore esthetic and function. Alveolar ridge preservation can be applied to minimize dimensional changes with a new socket grafting material, an autogenous dentin graft, produced by mechanically and chemically processing natural teeth. This study assessed the safety and efficacy of using autogenous dentin biomaterial in alveolar ridge preservation.

Materials and Methods

Patients with nonrestorable maxillary anterior teeth bounded by natural sound teeth were included in this study. After a detailed clinical and tomographic examination, eligible participants were randomly allocated into two groups. The control group had spontaneous healing of extraction sockets. The study group had their extraction sockets filled with autogenous dentin biomaterial after processing their extracted retained roots with the KometaBio device. Standardized cone beam computed tomography (CBCT) scans were repeated four months later. A full-thickness mucoperiosteal flap reflection was achieved under local anesthesia to get core biopsies for histomorphometric analysis, and dental implants were placed at the same session.

Results

A total of 32 eligible patients were included in this study (n = 16 in each group). Both groups had significantly higher facial soft tissue thickness after four months than baseline (p < 0.05). However, the study group showed statistically significant lesser dimensional changes than the control group according to the standardized CBCT scans. Furthermore, core biopsies confirmed an excellent remodeling of the autogenous dentin biomaterial in the study group. In comparison, only new thin bone trabeculae-filled sockets were in the control group.

Conclusion

Autogenous dentin graft can be safely and successfully used for alveolar ridge preservation. Optimal graft remodeling histologically, better ridge dimensional stability, and uneventful wound healing support its clinical application. This trial is registered with TCTR20220615002.

Effect of alveolar ridge preservation on peri-implant mucositis and peri-implantitis prevalence: A multicenter, cross-sectional study

OBJECTIVES

Alveolar ridge preservation (ARP) is a procedure with the aim to reduce bone resorption that occurs after tooth extraction, facilitating the following implant placement. The aim of this cross-sectional study was to evaluate the prevalence of mucositis and peri-implantitis around implants inserted in sites treated with ARP and to investigate possible risk factors.

MATERIALS AND METHODS

Patients who received at least one dental implant inserted in a grafted socket were considered eligible for this study. Patients were recalled for a follow-up visit; medical history, clinical and demographic data were collected. Univariate logistic regression analyses have been performed for both implant-level and patient-level variables. Indeed, moderation analysis was used to investigate the indirect relationship between age and marginal bone level.

RESULTS

Fifty-one patients who received 61 implants were enrolled in this cross-sectional study. Thirty-three implants were classified as "healthy" (54.1%), 23 implants showed signs of peri-implant mucositis (37.7%), and 5 implants were diagnosed with peri-implantitis (8.2%). Data analyzed at the patient level showed that 49% of the patients were healthy, 45.1% of the patients had mucositis and 5.9% of the patients were affected by peri-implantitis. Mandibular sites and type III grafted sockets showed a significant association with peri-implantitis; in addition, a history of periodontitis and an increase in age showed higher risks of developing mucositis or peri-implantitis.

CONCLUSIONS

Implants inserted in grafted sockets showed favorable rates of healthy implants in the long term.

CLINICAL RELEVANCE

The ridge preservation procedures do not seem to increase the risk of developing mucositis or peri-implantitis.

Biomaterials for Alveolar Ridge Preservation as a Preoperative Procedure for Implant Treatment: History and Current Evidence

In implant treatment, the reduction and structural changes in the alveolar ridge that occur after tooth extraction limit the length, width, and placement position of the implant body, impair esthetics, and, in some cases, make implant placement difficult. To solve these problems, an alveolar ridge preservation (ARP) technique, which is performed simultaneously with tooth extraction, generally aims to promote bone regeneration and prevent alveolar ridge reduction by filling the extraction socket with bone graft material and then covering it with a barrier membrane to protect against the invasion of epithelial tissue. The extraction socket provides a favorable environment for bone regeneration throughout the healing period because the blood supply is abundant, and it effectively retains the bone graft material by using the remaining bone wall of the socket. In recent years, advances in bioengineering technology have led to the development of graft materials with various biological properties, but there is currently no clear consensus regarding the selection of surgical techniques and materials depending on the condition of the alveolar ridge. This review will provide a comprehensive survey of the evidence accumulated to date on ARP, present many cases according to the clinical situation, and discuss various treatment options.

Post-extraction volumetric analysis of alveolar ridge contour using subepithelial connective tissue graft in esthetic zone: a randomized controlled clinical trial

OBJECTIVES

The aim of this randomized clinical trial was to assess the alveolar ridge contour after soft tissue augmentation using subepithelial connective tissue graft (SCTG) buccal to fresh extraction sockets in patients with thin buccal bone, versus minimally-traumatic extraction followed by spontaneous healing solely.

MATERIALS AND METHODS

Forty non-restorable maxillary teeth in the esthetic zone were randomly assigned into two groups: minimally-traumatic extraction with SCTG (test) and minimally-traumatic extraction followed by spontaneous healing (control). The outcomes assessed included linear volumetric change of buccal soft tissue contour, vertical tissue loss, gingival thickness (GT), and interdental papilla (IDP) height after 6 months.

RESULTS

The SCTG group showed a significant improvement (P < 0.001) in all outcomes after 6 months. The SCTG group showed a statistically significant (P < 0.001) gain in the buccal soft tissue volumetric change compared to the control group. The SCTG group showed a statistically significant increase in GT (P < 0.001) and IDP height (P < 0.05) after 6 months compared to the control group.

CONCLUSIONS

The use of SCTG buccal to extraction sockets in the anterior maxilla might be considered as a predictable approach for preserving the alveolar ridge contour.

CLINICAL RELEVANCE

SCTG buccal to extraction sockets might counteract post-extraction hard and soft tissue alterations in the esthetic zone.

Application of virtual technology to maximize esthetics and function in the restoration of anterior traumatic dental injuries

The restoration of multiple teeth with traumatic injury in the esthetic zone is complex. For the present patient, an intraoral scanner, a facial scanner, a jaw motion analyzer, and cone beam computed tomography were applied to collect patient data and establish a virtual dental patient. The virtual technology increased the accuracy of tooth- and implant-supported crowns in both appearance and occlusion.

Complications following alveolar ridge augmentation procedures

Oral rehabilitation through implant supported dental restorations often requires a ridge augmentation procedure (RAP) prior to implant fixture placement since tooth extraction/loss results in alveolar ridge deficiencies. Although RAP-related surgical techniques and biomaterials have been in practice for several decades, outcomes are not always predictable. Post-surgical complications experienced during the early or late wound healing phases may jeopardize the targeted ideal ridge dimensions, required for implant fixture placement, and may have other consequences, such as negatively impacting the patient's quality of life. This review describes reported post-surgical complications following RAP under the following subtitles: complications by tissue type, complications in function and aesthetics, complications by healing time, complications by biomaterial type, and complications by surgical protocol modalities. Specifically, RAP performed by using particulate bone graft substitutes and related complications are explored. Modalities developed to prevent/manage these complications are also discussed.

Is alveolar ridge preservation an overtreatment?

The morphology and dimensions of the postextraction alveolar ridge are important for the surgical and restorative phases of implant treatment. Adequate new bone formation and preservation of alveolar ridge dimensions following extraction will facilitate installation of the implant in a restorative position, while preservation of soft tissue contour and volume is essential for an aesthetic and implant-supported restoration with healthy peri-implant tissues. Alveolar ridge preservation (ARP) refers to any procedure that aims to: (i) limit dimensional changes in the alveolar ridge after extraction facilitating implant placement without additional extensive bone and soft tissue augmentation procedures (ii) promote new bone formation in the healing alveolus, and (iii) promote soft tissue healing at the entrance of the alveolus and preserve the alveolar ridge contour. Although ARP is a clinically validated and safe approach, in certain clinical scenarios, the additional clinical benefit of ARP over unassisted socket healing has been debated and it appears that for some clinicians may represent an overtreatment. The aim of this critical review was to discuss the evidence pertaining to the four key objectives of ARP and to determine where ARP can lead to favorable outcomes when compared to unassisted socket healing.

Soft tissue outcomes following alveolar ridge preservation with/without primary flap closure for periodontally damaged extraction socket: A randomized clinical trial

INTRODUCTION

The changes in soft tissue profile following alveolar ridge preservation (ARP) with/without primary flap closure (PC) in periodontally damaged sockets have yet to be discovered.

METHODS

For periodontally damaged non-molar extraction sockets, ARP with PC (group PC)/without PC (group SC) was performed using granule-type xenogeneic bone substitute material and a collagen barrier. Intraoral scans were performed at the time of ARP and 4 months thereafter. Superimposition of STL files was performed to examine tissue change on the soft tissue level. The level of mucogingival junction (MGJ) was also evaluated.

RESULTS

A total of 28 patient (13 in group PC, 15 in group SC) completed the study. Soft tissue profile change was evaluated only when the measurement level was located on the non-mobile tissue. Group PC tended to shrink less on the long axis of the extraction socket than group SC (-4.3 ± 3.1 mm vs. -5.9 ± 4.4 mm at the 1 mm below the pre-extraction gingival margin, p > 0.05). Profilometric analysis (on the region of interest) also have a tendency of less tissue profile change in group PC than group SC (-1.0 ± 0.8 mm vs. -1.3 ± 0.5 mm, p > 0.05). The MGJ level change was not statistically significantly different between the groups (p > 0.05) even though the MGJ level was located more apically at 4 months in group SC compared with group PC.

CONCLUSIONS

Alveolar ridge preservation with PC tended to yield less soft tissue shrinkage than ARP without PC.

Volumetric analysis on the use of customized healing abutments with or without connective tissue graft at flapless maxillary immediate implant placement: A randomized clinical trial

OBJECTIVES

To evaluate buccal volume change after using a customized healing abutment with or without connective tissue grafts (CTG) in flapless maxillary immediate implant placement (IIP).

MATERIALS AND METHODS

The present study was designed as a randomized clinical trial (RCT). Patients treated with flapless maxillary IIP were allocated into two groups, both receiving a customized healing abutment, and additionally, the test group received a CTG. A cone-beam computerized tomography (CBCT) allowed to access the initial buccal bone thickness (BT). Digital impressions were taken prior to extractions (T0), 1 month (T1), 4 months (T2), and 12 months (T3) after implant insertion and superimposed with computer software allowing to compute variables related to buccal volume variation (BVv) and total volume variation (TVv) (ClinicalTrials.gov: NCT05060055).

RESULTS

Thirty-two patients (mean age 48 ± 11 years), sixteen in each group, were evaluated after a 12-month period. After 1 year of treatment, no significant differences were found between groups, although in participants with BT ≤1 mm, control and test groups showed a BVv of -14.18 ± 3.49% and -8.30 ± 3.78%, respectively (p = .033). Regarding mucosa height variation variables, the control group showed approximately the triple vertical recession in both papillae.

CONCLUSIONS

The placement of a CTG was not capable of completely maintaining the initial peri-implant tissue architecture, although in thin-bone phenotypes, less dimensional changes are expected when a CTG was used.

Enamel matrix derivative for alveolar ridge preservation: A randomized controlled trial

OBJECTIVE

The aims of this clinical trial were to evaluate the radiographic dimensional changes in alveolar ridge and patient-reported outcomes following tooth extraction and alveolar ridge preservation (ARP) using either deproteinized bovine bone mineral (DBBM) with EMD or DBBM alone.

METHODS

Participants requiring at least one posterior tooth extraction and ARP were randomly allocated into two treatment groups: ARP using either DBBM with EMD or DBBM alone. Cone-beam computed tomography (CBCT) images were recorded immediately prior to extraction and at 6 months. Changes in alveolar ridge height (ARH) and alveolar ridge width (ARW) at 1, 3, and 5 mm were recorded.

RESULTS

A total of 18 participants with 25 preserved sites were evaluated. ARH and ARW changed significantly from baseline to 6 months for both treatment groups but the difference between the groups was not statistically significant over the 6-month follow-up period (ARH: DBBM/EMD 1.26 ± 1.53 mm vs. DBBM 2.26 ± 1.60 mm; ARW-1 DBBM/EMD 1.98 ± 1.80 mm vs. DBBM 2.34 ± 1.89 mm). A significant difference, favoring DBBM with EMD group, was observed in percentage of sites that had less than 1 mm loss in ARH (54.5% sites in DBBM/EMD group vs. 14.3% sites in DBBM alone group). The participants' perception of bruising, bleeding, and pain in the first two postoperative days was significantly in favor of DBBM alone group.

CONCLUSIONS

There were no significant differences in radiographic mean measurements of ARH and ARW following ARB with DBBM and EMD or DBBM alone.

Alveolar ridge preservation: Complications and cost-effectiveness

Alveolar ridge preservation is routinely indicated in clinical practice with the purpose of attenuating postextraction ridge atrophy. Over the past two decades numerous clinical studies and reviews on this topic have populated the literature. In recent years the focus has primarily been on analyzing efficacy outcomes pertaining to postextraction dimensional changes, whereas other relevant facets of alveolar ridge preservation therapy have remained unexplored. With this premise, we carried out a comprehensive evidence-based assessment of the complications associated with different modalities of alveolar ridge preservation and modeled the cost-effectiveness of different therapeutic modalities as a function of changes in ridge width and height. We conclude that, among allogeneic and xenogeneic bone graft materials, increased expenditure does not translate into increased effectiveness of alveolar ridge preservation therapy. On the other hand, a significant association between expenditure on a barrier membrane and reduced horizontal and vertical ridge resorption was observed, though only to a certain degree, beyond which the return on investment was significantly diminished.

Local Concentrations of TGF-β1 and IGF-1 Appear Determinant in Regulating Bone Regeneration in Human Postextraction Tooth Sockets

Healing after tooth extraction involves a series of reparative processes affecting both alveolar bone and soft tissues. The aim of the present study was to investigate whether activation of molecular signals during the healing process confers a regenerative advantage to the extraction socket soft tissue (ESsT) at 8 weeks of healing. Compared to subepithelial connective tissue graft (CTG), qRT-PCR analyses revealed a dramatic enrichment of the ESsT in osteogenic differentiation markers. However, ESsT and CTG shared characteristics of nonspecialized soft connective tissue by expressing comparable levels of genes encoding abundant extracellular matrix (ECM) proteins. Genes encoding the transforming growth factor-β1 (TGF-β1) and its receptors were strongly enriched in the CTG, whereas the transcript for the insulin-like growth factor-1 (IGF-1) showed significantly high and comparable expression in both tissues. Mechanical stimulation, by the means of cyclic strain or matrix stiffness applied to primary ESsT cells (ESsT-C) and CTG fibroblasts (CTG-F) extracted from the tissue samples, revealed that stress-induced TGF-β1 not exceeding 2.3 ng/mL, as measured by ELISA, in combination with IGF-1 up to 2.5 ng/mL was able to induce the osteogenic potential of ESsT-Cs. However, stiff matrices (50 kPa), upregulating the TGF-β1 expression up to 6.6 ng/mL, caused downregulation of osteogenic gene expression in the ESsT-Cs. In CTG-Fs, endogenous or stress-induced TGF-β1 ≥ 4.6 ng/mL was likely responsible for the complete lack of osteogenesis. Treatment of ESsT-Cs with TGF-β1 and IGF-1 proved that, at specific concentrations, the two growth factors exhibited either an inductive-synergistic or a suppressive activity, thus determining the osteogenic and mineralization potential of ESsT-Cs. Taken together, our data strongly warrant the clinical exploration of ESsT as a graft in augmentative procedures during dental implant placement surgeries.

Influence of partially exposed nonabsorbable membrane for alveolar ridge preservation: A randomized controlled trial

AIM

This randomized controlled trial evaluated the impact of a partially exposed non-absorbable membrane (dPTFE) in Alveolar Ridge Preservation (ARP) procedures on clinical, tomographic, immunoenzymatic, implant-related, and patient-centered outcomes.

MATERIALS AND METHODS

Patients with a hopeless maxillary single-rooted tooth demanding rehabilitation with implants were included. Patients were randomized into two groups: dPTFE (n = 22)-tooth extraction followed by ARP using a partially exposed dPTFE membrane; USH (n = 22)-unassisted socket healing. Clinical and tomographic analyses were performed at baseline and after 3 months. After 3 months, patients received one dental implant. Implant stability quotient was obtained following implant placement. Bone-related markers were analyzed in bone biopsies using an immunoenzymatic assay.

RESULTS

Greater gain in Keratinized Mucosa Width (KMW) was observed in the dPTFE (1.33 ± 0.98 mm) compared to USH (0.59 ± 0.98 mm) (Mann-Whitney test, Z = 2,28, p < 0.05). USH showed a reduction of pain/discomfort, edema, and interference with daily life from the seventh day (Friedman/Wilcoxon test, maxT = 7.48, 8.00, and 5.92, respectively, p < 0.05). dPTFE presents a reduction of edema and interference with daily life from the 7th day and pain/discomfort from the 14th day (Friedman/Wilcoxon test, maxT = 5.40, 5.26, and 4.78, respectively, p < 0.05). The dPTFE group presented higher pain/discomfort in the 35 and 42 days and higher edema from 7 to 42 days postoperatively than USH group (Mann-Whitney test, p < 0.05). No differences between groups were observed in the tomographic measures, immunoenzymatic analysis, and implant stability (p > 0.05).

CONCLUSION

dPTFE was superior to USH by increasing KMW gain. However, dPTFE without bone graft presented similar bone loss compared to USH. This clinical trial was not registered prior to participant recruitment and randomization (NCT04329351).

Clinical, radiographic, and esthetic evaluation of immediate implant placement with buccal bone dehiscence in the anterior maxilla: A 1-year prospective case series

OBJECTIVES

To evaluate the clinical, radiographic, and esthetic outcomes of immediate implant placement with buccal bone dehiscence in the anterior maxilla.

METHODS

In this case series, implants were inserted immediately after tooth extraction in sockets with buccal bone dehiscence. Guided bone regeneration (GBR) with a papilla preservation flap and simultaneous connective tissue grafting (CTG) was used. The following outcome variables were measured: mid-facial mucosal recession, probing depth, bleeding on probing, Pink Esthetic Score (PES), marginal bone loss, and thickness of buccal bone plate (TBP).

RESULTS

12 patients were recruited. Stable mid-facial mucosal level (-0.03 ± 0.17 mm) and excellent soft-tissue esthetic outcomes (PES, 9.17 ± 0.72) were achieved at 1 year. The TBP at platform level was 2.01 ± 0.31 mm at 1-year follow up with a resorption rate of 28.90% ± 15.14%.

CONCLUSIONS

Immediate implant placement using GBR performed with a papilla preservation approach and simultaneous CTG is a feasible treatment procedure in compromised extraction sockets in the anterior region. Favorable esthetic outcomes and buccal bone thickness were obtained. Further studies were needed to evaluate the long-term tissue alteration.

Influence of healing time on the outcomes of alveolar ridge preservation using a collagenated bovine bone xenograft: A randomized clinical trial

AIM

To evaluate the healing outcomes in non-molar post-extraction sockets filled with deproteinized bovine bone mineral with collagen (DBBM-C) as a function of time.

MATERIALS AND METHODS

Patients in need of non-molar tooth extraction were randomly allocated into one of three groups according to the total healing time (A-3 months; B-6 months; C-9 months). The effect of alveolar ridge preservation (ARP) therapy via socket filling using DBBM-C and socket sealing with a porcine collagen matrix (CM) was assessed based on a panel of clinical, digital, histomorphometric, implant-related, and patient-reported outcomes.

RESULTS

A total of 42 patients completed the study (n = 14 in each group). Histomorphometric analysis of bone core biopsies obtained at the time of implant placement showed a continuous increase in the proportion of mineralized tissue with respect to non-mineralized tissue, and a decrease in the proportion of remaining xenograft material over time. All volumetric bone and soft tissue contour assessments revealed a dimensional reduction of the alveolar ridge overtime affecting mainly the facial aspect. Linear regression analyses indicated that baseline buccal bone thickness is a strong predictor of bone and soft tissue modelling. Ancillary bone augmentation at the time of implant placement was needed in 16.7% of the sites (A:2; B:1; C:4). Patient-reported discomfort and wound healing index scores progressively decreased over time and was similar across groups.

CONCLUSIONS

Healing time influences the proportion of tissue compartments in non-molar post-extraction sites filled with DBBM-C and sealed with a CM. A variable degree of alveolar ridge atrophy, affecting mainly the facial aspect, occurs even after performing ARP therapy. These changes are more pronounced in sites exhibiting thin facial bone (≤1 mm) at baseline (Clinicaltrials.gov NCT03659617).

Soft-tissue dimensional change following guided bone regeneration on peri-implant defects using soft-type block or particulate bone substitutes: 1-year outcomes of a randomized controlled clinical trial

AIM

To compare the peri-implant soft-tissue dimensional changes following guided bone regeneration between particulate (particle group) and collagenated soft-block-type (block group) biphasic calcium phosphate (BCP).

MATERIALS AND METHODS

This study investigated 35 subjects: 18 in the particle group and 17 in the block group. Cone-beam computed tomography obtained at 6 months post surgery and optical impressions taken periodically (before surgery, 6 months post surgery, and 1 year post surgery) were superimposed. The ridge contour changes over time and the peri-implant mucosal thicknesses were measured diagonally and horizontally, and analysed statistically.

RESULTS

The increases in diagonal (1.12 ± 0.78 mm) and horizontal (2.79 ± 1.90 mm) ridge contour of the block group were significantly higher than those in the particle group during the first 6 months (p < .05); however, the contour hardly changed thereafter (diagonal: 0.07 ± 0.75 mm; horizontal: -0.34 ± 1.26 mm), resulting in the 1-year contour changes similar between the two groups. Regardless of the type of BCP, the ridge contour increased significantly over 1 year when the dehiscence defect had a contained configuration (p < .05).

CONCLUSIONS

The increase in soft-tissue dimensions for 1 year was similar between the two groups. The mucosal contour increase was larger when the surgery was conducted in a more contained defect, and this was not influenced by the type of BCP.

Current perspectives of residual ridge resorption: Pathological activation of oral barrier osteoclasts

PURPOSE

Tooth extraction is a last resort treatment for resolving pathological complications of dentition induced by infection and injury. Although the extraction wound generally heals uneventfully, resulting in the formation of an edentulous residual ridge, some patients experience long-term and severe residual ridge reduction. The objective of this review was to provide a contemporary understanding of the molecular and cellular mechanisms that may potentially cause edentulous jawbone resorption.

STUDY SELECTION

Clinical, in vivo, and in vitro studies related to the characterization of and cellular and molecular mechanisms leading to residual ridge resorption.

RESULTS

The alveolar processes of the maxillary and mandibular bones uniquely juxtapose the gingival tissue. The gingival oral mucosa is an active barrier tissue that maintains homeostasis of the internal organs through its unique barrier immunity. Tooth extraction not only generates a bony socket but also injures oral barrier tissue. In response to wounding, the alveolar bone socket initiates regeneration and remodeling through coupled bone formation and osteoclastic resorption. Osteoclasts are also found on the external surface of the alveolar bone, interfacing the oral barrier tissue. Osteoclasts in the oral barrier region are not coupled with osteoblastic bone formation and often remain active long after the completion of wound healing, leading to a net decrease in the alveolar bone structure.

CONCLUSIONS

The novel concept of oral barrier osteoclasts may provide important clues for future clinical strategies to maintain residual ridges for successful prosthodontic and restorative therapies.

Controversies in the dental implant treatment planning for anterior maxillary aesthetic zone - A review

The anterior maxillary region being an aesthetic zone remains critical in decision-making when it comes to replacing a tooth. Treatment planning to place dental implants in aesthetic zone like anterior maxilla needs paramount attention in order to provide best of the treatment outcomes from aesthetic point of view. As the field of dental implants tend to evolve continuously, newer concepts with inadequate research come into practise on regular basis. In this article, some of the controversies regarding dental implant placement and treatment process related to anterior maxillary aesthetic zone are discussed with literature to support evidence.

Hard and soft tissue evaluation of alveolar ridge preservation compared to spontaneous healing: a retrospective clinical and volumetric analysis

PURPOSE

The remodeling process following tooth extraction can be observed as horizontal and vertical bone reduction of the alveolar ridge. Preservation procedures such as alveolar ridge preservation (ARP) aim to maintain the 3D volume of the extraction site. This retrospective study analyzed differences in the hard and soft tissue changes in patients treated with either spontaneous healing or ARP.

METHODS

After tooth extraction, the patients were treated either by spontaneous socket healing (SH group) or with ARP using a xenograft and a resorbable membrane (ARP group). One week before and 6 months after extraction, the patients underwent cone beam computed tomography. A volumetric analysis was performed by superimposing the digital models of the two time points. Intraoral radiography was performed after implant placement, upon prosthesis delivery, and at 1-year post-treatment. An esthetic assessment was conducted using the Pink Esthetic Score (PES). The patients' overall satisfaction with the implant restoration was investigated at 12 months.

RESULTS

Intragroup comparisons revealed significant differences between baseline and the 6-month follow-up in both groups at the measured locations (1 mm, 3 mm, and 5 mm below the most coronal aspect of the alveolar ridge) showing a reduction of the horizontal width (P < 0.05). Additionally, after treatment, the horizontal width at 1 mm was significantly different in the SH and ARP groups (P < 0.001), with mean changes of 2.03 ± 0.54 mm and 0.86 ± 0.49 mm, respectively. ARP was associated with an increased PES (11.6 ± 2.2) and a reduction in patients requiring additional grafting procedures in subsequent treatment phases (9% vs 26%; P = 0.11).

CONCLUSIONS

In both groups, significant horizontal and vertical bone loss was observed after the extraction. ARP can reduce linear and volumetric shrinkage of the alveolar ridge, leading to improved outcomes. It can also simplify implant restoration.

Assessment of soft and hard tissue characteristics of ridge preservation at molar extraction sites with severe periodontitis: a randomized controlled trial

Background

Changes in alveolar bone dimension after tooth extraction may affect placement of the subsequent implant, resulting in ridge deficiency that can adversely impact long-term implant stability or aesthetics. Alveolar ridge preservation (ARP) was effective in reducing the amount of ridge resorption following tooth extraction. There is sparse evidence regarding the benefit of ARP at periodontally compromised molar extraction sockets. This study will be a randomized trial to assess the soft tissue contour, radiographical, and histological changes of ARP at molar extraction sites in order to compare severe periodontitis cases with natural healing results and determine the most beneficial and least traumatic clinical treatment for such patients.

Methods

This research is designed as a two-group parallel randomized controlled trial. The total number of tooth extraction sites will be 70 after calculation with power analysis. Teeth will be randomly assigned to two groups with the test group conducting ridge preservation and the control group healing naturally. Periodontal examination, cone beam-computed tomography (CBCT) data, and stereolithographic (STL) files obtained by intraoral scanning will be collected through the follow-up period, and bone biopsy samples would be obtained during implant surgery. The primary outcomes are the vertical and horizontal change of alveolar ridge measured on CBCT images, soft tissue contour changes evaluated by superimposing the digital impressions, alterations of mucosa thickness (as measured by superimposing the CBCT data and STL files), histological features of implant sites and periodontal parameter changes. The secondary outcomes are patient-reported post-operative reaction and conditions of simultaneous bone graft or sinus lifting procedures during implantation.

Discussion

This study will provide information about hard and soft tissue dimension changes and histomorphology evaluation following ARP and natural healing in periodontally compromised molar sites, which may contribute to complement the missing information of ARP at periodontally compromised molar extraction sockets.

Trial registration

Chinese Clinical Trial Register (ChiCTR) ChiCTR2200056335. Registered on February 4, 2022, Version 1.0.

Soft and hard tissue changes after immediate implant placement with or without a sub-epithelial connective tissue graft: results from a 6-months pilot randomized controlled clinical trial

AIM

The present pilot RCT aimed to investigate the influence of a connective tissue graft (CTG) in combination with the immediate implant placement (IIP) on hard and soft tissues healing, without a bone replacement graft in the gap between the implant and the socket walls.

MATERIAL AND METHODS

Thirty patients requiring extraction of one anterior tooth (from premolar to premolar) were randomly assigned to one of the two treatment groups (test: IIP+CTG; control: IIP). Cone-beam computed tomography (CBCT) and optically scans were performed before tooth extraction and at 6-months follow-up. Then, DICOM files were superimposed in order to allow the evaluation of osseous ridge and buccal bone changes, while the superimposition of DICOM and STL (Standard Tessellation Language) files allowed for evaluating of soft tissue contour. For testing the differences between the two groups, the non-parametric test as Wilcoxon rank-sum test, was used.

RESULTS

Twenty-six out of the thirty enrolled patients, attended the 6-month follow-up visit. The 4 patients of control group that were lost to follow-up, were analyzed under the intention-to-treat principle. No statistically significant differences between the groups were observed for the vertical buccal bone resorption (p=0.90), as well as for the horizontal buccal bone resorption at all measured levels. Significant differences were found between test and control groups in the horizontal dimensional changes of osseous ridge at the most coronal aspect (p=0.0003 and p=0.02). Changes of tissue contour ranged between -0.32 and -0.04 mm in the test group, and between -1.94 and -1.08 mm in the control group, while changes of soft tissue thickness varied between 1.33 and 2.42 mm in the test group, and between -0.16 and 0.88 mm in the control group, with statistically significant differences for both variables at all measured levels. At 6 months, the mean volume increase was 6.76±8.94 mm³ and 0.16±0.42 mm³ in the test and control groups, respectively, with statistically significant difference.

CONCLUSIONS

The findings of the present study indicate that the adjunct of a connective tissue graft at the time of immediate implant placement, without bone grafting, does not influence vertical bone resorption. Within the limits of the present study, it can be suggested that the adjunct of a connective tissue graft at the time of immediate implant placement, without bone grafting, reduces the horizontal changes of the alveolar ridge. Moreover, it allows maintenance of the tissue contour due to an increase in soft tissue thickness.

Evaluation of Deviations between Computer-Planned Implant Position and In Vivo Placement through 3D-Printed Guide: A CBCT Scan Analysis on Implant Inserted in Esthetic Area

Background: Implant rehabilitation in cases of monoedentulism in the esthetic area is a challenge for the clinician. The aim of our study was to test the diagnostic–therapeutic accuracy of computer-guided implant placement in the esthetic area. Methods: Postimplant surgery cone beam computed tomography (CBCT) scans were retrospectively analyzed to assess the accuracy of computer-guided implant placement compared to the preoperative computer-digital planned implant position. We selectively enrolled CBCT scans of patients who underwent immediate or delayed implant placement of a single maxillary incisor, treated with computer-guided implant surgery through a tooth-supported digitally designed 3D printed guide. Our analysis consisted of three digital measurements: the mean deviation of the implant axis, and the mean mesiodistal implant deviation measured both at the apex and at the head of the implant. Results: A total of 95 implants were placed in 95 patients (60 Males, 35 Females; age from 27 to 45-year-old). Congruence analysis showed a mean deviation of implant axis of 1.04° ± 0.56° in sagittal projection, a mean mesiodistal implant deviation between adjacent teeth of 0.14 mm ± 0.07 mm at implant head level and 0.8 mm ± 0.3 mm at the apex in axial projection. Conclusions: computer-guided implant placement through a tooth-supported guide was extremely accurate in the esthetic area because the deviations between the real implant position and the preoperative planning was not clinically relevant.

Gingival thickness threshold and probe visibility through soft tissue: a cross-sectional study

Objectives

The aim was to retrieve the threshold of gingival thickness (GT), where the attribute of gingival translucency through probe visibility was altered.

Methods

In 200 patients, the soft tissue thickness was evaluated at both central mandibular incisors using ultrasound quantification (USD). Additionally, probe visibility was determined using a standard periodontal probe (PB) (CPU 15 UNC, Hu-Friedy), inserted 1 mm deep into the gingival sulcus. Frequencies and relative frequencies were calculated. Repeatability analyses and receiver operating characteristics (ROC) were conducted to determine the USD cut-off point for probe visibility.

Results

Regression model indicated that the probe was not visible at a thickness of 0.82 mm for the mandibular left central incisor (95% CIs 0.77, 0.86) and became visible at a thickness of 0.69 mm (95% CIs 0.65, 0.72). The respective values for the mandibular right central incisor were 0.82 mm (95% CIs 0.77, 0.87) and 0.70 mm (0.68, 0.74). ROC analysis confirmed the retrieved regression results by indicating the best fitting balance for specificity and sensitivity at a thickness of 0.8 mm for both mandibular incisors.

Conclusions

In the frame of the current study, the data revealed that gingiva becomes non-transparent at a thickness of approximately 0.8 mm.

Clinical relevance

Probe visibility at mandibular incisors for the discrimination between thin and thick soft tissues was correlated with a gingival thickness of 0.8 mm and a high repeatability.

Influence of buccal emergence profile designs on peri-implant tissues: A randomized controlled trial

BACKGROUND

The prosthetic emergence profile design might be an important factor in postsurgical mucosal recession etiology. Therefore, a restorative buccal emergence profile designed correctly might reduce gingival margin recession.

PURPOSE

To compare the marginal gingival level and the width/height (W/H) ratio between two profile configurations of single implant-supported restorations at molar sites.

MATERIALS AND METHODS

Twenty-one patients requiring a single mandibular molar tooth replacement with supracrestal mucosal thickness ≥2 mm were recruited and randomly assigned to a prosthesis buccal emergence profile design based on the buccal mucosal W/H ratio (Test Group) or maintained the original emergence profile of the healing abutment (Control Group). Assessments were made before delivery of the definitive restoration (T0), at prosthesis placement (T1), one (T2), and 12 (T3) months after loading. The gingival margin level change (△GM), initial emergence angle, buccal mucosal W/H ratio, marginal bone loss (MBL), implant failure, and complications were assessed.

RESULTS

The gingival recession in the test group (0.13 ± 0.32 mm) was significantly lower than in the control group (0.63 ± 0.38 mm) at T3 (p = 0.006). The initial emergence angle in the test group (31.4 ± 7.22 degrees) was significantly lower than the control group (40.0 ± 7.60 degrees) (p = 0.025). The W/H ratio in the test group at T2 was significantly higher than at T0 but remained stable thereafter. The W/H ratio presented a continued rising trend in the control group.

CONCLUSIONS

When the initial supracrestal soft tissue thickness was ≥2 mm, a restorative emergence profile based on the W/H ratio significantly reduced gingival margin recession. An emergence angle of 32.4 degrees showed better behavior in maintaining the gingival margin than 40 degrees.

CLINICAL TRIAL REGISTRATION NUMBER

ChiCTR190002210.

Alveolar ridge preservation reduces the need for ancillary bone augmentation in the context of implant therapy

Background

There is limited information on the need for bone augmentation in the context of delayed implant placement whether alveolar ridge preservation (ARP) is previously performed or not. The primary aim of this retrospective cohort study was to evaluate the efficacy of ARP therapy after tooth extraction compared with unassisted socket healing (USH) in reducing the need for ancillary bone augmentation before or at the time of implant placement.

Methods

Adult subjects that underwent non‐molar single tooth extraction with or without simultaneous ARP therapy were included in this study. Cone beam computed tomography scans obtained before tooth extraction and after a variable healing period were used to record the baseline facial bone thickness and to virtually plan implant placement according to a standard method. A logistic regression model was used to evaluate the effect of facial alveolar bone thickness upon tooth extraction and baseline therapy (USH or ARP) on the need for additional bone augmentation, adjusting for several covariates (i.e., age, sex, baseline KMW, and tooth type).

Results

One hundred and forty subjects that were equally distributed between both baseline therapy groups constituted the study population. Implant placement was deemed virtually feasible in all study sites. Simultaneous bone augmentation was considered necessary in 60% and 11.4% of the sites in the USH and ARP group, respectively. Most of these sites (64.2% in the USH group and 87.5% in the ARP group) exhibited a thin facial bone phenotype (<1 mm) at baseline. Logistic regression revealed that the odds of not needing ancillary bone augmentation were 17.8 times higher in sites that received ARP therapy. Furthermore, the need for additional bone augmentation was reduced 7.7 times for every 1 mm increase in facial bone thickness, regardless of baseline therapy.

Conclusions

Based on a digital analysis, ARP therapy, compared with USH, and thick facial alveolar bone largely reduce the need for ancillary bone augmentation at the time of implant placement in non‐molar sites.

The beyond the gap filling approach: Modeling facial and interproximal tissues and improving esthetics for anterior flapless immediate implant placement

OBJECTIVE

Maintenance of adequate interproximal tissue height between an implant and a natural tooth or between adjacent implants represents an esthetic challenge in implant dentistry. The aim of this case report is to describe a modified technique referred to as the beyond the gap filling (BGF) approach designed to improve the horizontal and vertical components of the facial aspect and particularly the height of interproximal bone peaks around immediately placed implants into fresh extraction sockets.

CLINICAL CONSIDERATIONS

Four patients (five teeth) requiring anterior tooth extraction were treated with the BGF approach that included: (a) minimally traumatic tooth extraction; (b) immediate implant placement without flap elevation; (c) installation of a narrow profile healing abutment to protect the implant during grafting; (d) grafting with a construct with 90% bovine bone granules and 10% porcine collagen packed coronally to the facial and interproximal bone walls above the level of the bone crest; and (e) delivery of an immediate restoration.

CONCLUSIONS

The current report suggests that the level/height of the interproximal bone crests between an implant and a natural tooth or between two adjacent implants can be improved by the BGF approach and, consequently, papilla height can be maintained in cases with a high risk of papilla height collapse and, consequently, esthetic outcomes can be maximized.

CLINICAL SIGNIFICANCE

The BGF is a simple technique to be used by clinicians to prevent significant papilla collapse in anterior immediate implants and consequently achieve maximum esthetic outcomes in implant dentistry.

Clinical application of concentrate growth factors combined with bone substitute in Alveolar ridge preservation of anterior teeth

Objective

To investigate the clinical effect of concentrated growth factors (CGF) combined with deproteinized bovine bone mineral (DBBM) on Alveolar ridge preservation during implantology.

Methods

A total of 38 patients were selected and randomly divided into 2 groups, with 19 cases in each group. The extraction sockets were filled with DBBM with or without CGF. Visual analogue scale (VAS) pain score was recorded within1 week and Landry wound healing index (LWHI) was recorded at 1, 2 and 3 weeks after operation. CBCT was taken preoperatively and 3 and 6 months postoperatively to measure and compare the changes of vertical height, width and gray value of alveolar bone at extraction site. The changes of alveolar bone contour were observed clinically and compared between the two groups.

Results

The VAS score of CGF group was lower than control group on the 1st and 3rd day after operation (P < 0.05). The LWHI of CGF group was higher than control group 1 week after operation (P < 0.05). The absorption of the labial and palatal plates height and the width in the CGF group was significantly less than the control group at 3 months (P < 0.05). The gray value of alveolar bone in CGF group was significantly higher than control group at 3 months (P < 0.05). There was no significant difference in new bone contour between the two groups (P > 0.05). 94.7% cases in CGF group did not undergo bone grafting, which was significantly higher than control group (78.9%).

Conclusions

The use of CGF combined with DBBM can help to reduce postoperative pain at the early stage of healing, form sufficient keratinized gingival tissue, effectively maintain the height and width of alveolar bone in the three-dimensional direction and provide good conditions for implant repair in the future.

Esthetic complications in implant dentistry

Esthetic complications in implant dentistry have become a significant consideration for patients and practitioners. This review presents an appraisal on the current knowledge of the physiological peri-implant soft-tissue dimensions and factors that may compromise peri-implant tissue esthetics. Factors such as papilla fill adjacent to the implant and midfacial mucosal height are critical parameters that determine the esthetic success of implant-supported restorations. Papilla fill adjacent to a single dental implant appears to depend upon the clinical attachment level of the neighboring tooth. A horizontal inter-implant distance of at least 3 mm is necessary to ensure optimal interproximal mucosal embrasure between two adjacent implants in the anterior maxilla. In cases where implants cannot be placed at least 3 mm apart, a single implant with a cantilever bridge should be considered. Buccolingual implant positioning plays a major role in midfacial mucosal height. Soft-tissue volume grafting following immediate implant placement in the presence of a thin soft-tissue phenotype or simultaneous to surgical peri-implantitis therapy might help to overcome facial mucosa recession.

Management and sequelae of dental implant removal

Inappropriate and unnecessary implant therapy driven by an erroneous belief that dental implants provide enhanced function and esthetics over diseased or failing teeth has led to a growing burden of implant complications across the globe. Specifically, esthetic and biological complications frequently lead to the unfavorable prognosis of dental implants. Often, these cannot be managed predictably to improve the condition or satisfy patients' demands. In such circumstances, implant removal needs to be considered. Currently, minimally invasive methods based on reverse torque engineering are key to preserve peri-implant soft and hard tissues. Implant replacement is now feasible, as evidenced by the high survival rates of implants placed at previously failed sites. Notwithstanding these data, clinicians should still consider carefully the expendability of an implant and whether its replacement will satisfy the prosthetic, biomechanical, and esthetic demands of the patient. In the scenario where future implant placement is desired, protocols undertaken for soft/hard tissue grafting and implant placement should be based upon defect morphology and soft and hard-tissue characteristics. Currently, however, a lack of knowledge of the biological events and dimensional changes that arise following implant removal renders decision-making complex and challenging, and recommendations remain largely based upon empirical speculation. This chapter will review the indications for implant replacement for prosthetic, biomechanical, and esthetic complications, alongside considerations in decision-making, planning, implementation, and outcomes of implant replacement.

Classification Based on Extraction Socket Buccal Bone Morphology and Related Treatment Decision Tree

Background: Alveolar ridge preservation (ARP) can successfully reduce volumetric ridge changes. However, there is still no consensus on what technique is the most advantageous for each specific clinical scenario. Hence, the aim of the present paper was to provide a treatment decision tree to guide the choice of predictable ARP procedures based on extraction socket buccal bone morphology and integrity. Material and Methods: Three socket types (ST) are proposed and discussed based on buccal bone morphology (intact, dehiscence or fenestration). Results: A decision tree for ARP was developed in order to merge ST classification with suitable treatment modalities. In the decision tree, the issue of when to allow unassisted healing or ARP was discussed. Described methods included bone grafting and collagen plug, and absorbable membrane or non-resorbable membrane, with or without flap elevation. Conclusion: A decision tree for ARP procedures was provided to guide clinicians towards the most conservative and predictable treatment approach based on remaining socket anatomical structures after extraction.

Does initial buccal crest thickness affect final buccal crest thickness after flapless immediate implant placement and provisionalization: A prospective cone beam computed tomogram cohort study

BACKGROUND

Flapless immediate implant placement and provisionalization (FIIPP) in the aesthetic zone is still controversial. Especially, an initial buccal crest thickness (BCT) of ≤1 mm is thought to be disruptive for the final buccal crest stability jeopardizing the aesthetic outcome.

PURPOSE

To radiographically assess the BCT and buccal crest height (BCH) after 1 year and to calculate the correlation between initial and final achieved BCT.

MATERIALS AND METHODS

The study was designed as a prospective study on FIIPP. Only patients were included in whom one maxillary incisor was considered as lost. In six centers, 100 consecutive patients received FIIPP. Implants were placed in a maximal palatal position of the socket, thereby creating a buccal space of at least 2 mm, which was subsequently filled with a bovine bone substitute. Files of preoperative (T0), peroperative (T1) and 1-year postoperative (T3) cone beam computed tomogram (CBCT) scans were imported into the Maxillim™ software to analyze the changes in BCT-BCH over time.

RESULTS

Preoperatively, 85% of the cases showed a BCT ≤1 mm, in 25% of the patients also a small buccal defect (≤5 mm) was present. Mean BCT at the level of the implant-shoulder increased from 0.6 mm at baseline to 3.3 mm immediate postoperatively and compacted to 2.4 mm after 1 year. Mean BCH improved from 0.7 to 3.1 mm peroperatively, and resorbed to 1.7 mm after 1 year. The Pearson correlation of 0.38 between initial and final BCT was significant (p = 0.01) and therefore is valued as moderate. If only patients (75%) with an intact alveolus were included in the analysis, still a "moderate correlation" of 0.32 (p = 0.01) was calculated.

CONCLUSIONS

A "moderate correlation" was shown for the hypothesis that "thinner preoperative BCT's deliver thinner BCT's" 1 year after performing FIIPP.

Soft tissue dimensional changes after alveolar ridge preservation using different sealing materials: a systematic review and network meta-analysis

Background

Alveolar ridge preservation (ARP) is a proactive treatment option aiming at attenuating post-extraction hard and soft tissue dimensional changes. A high number of different types of biomaterials have been utilized during ARP to seal the socket, but their effectiveness in terms of soft tissue outcomes has rarely been investigated and compared in the literature.

Objective

To evaluate the efficacy of different types of membranes and graft materials in terms of soft tissue outcomes (keratinized tissue width changes, vertical buccal height, and horizontal changes) after ARP, and to assign relative rankings based on their performance.

Materials and methods

The manuscript represents the proceedings of a consensus conference of the Italian Society of Osseointegration (IAO).

PUBMED (Medline), SCOPUS, Embase, and Cochrane Oral Health’s Information Specialist were utilized to conduct the search up to 06 April 2021. English language restrictions were placed and no limitations were set on publication date. Randomized controlled trials that report ARP procedures using different sealing materials, assessing soft tissue as a primary or secondary outcome, with at least 6-week follow‐up were included.

Network meta-analysis (NMA) was performed using mean, standard deviation, sample size, bias, and follow-up duration for all included studies. Network geometry, contribution plots, inconsistency plots, predictive and confidence interval plots, SUCRA (surface under the cumulative ranking curve) rankings, and multidimensional (MDS) ranking plots were constructed.

Results

A total of 11 studies were included for NMA. Overall, the level of bias for included studies was moderate. Crosslinked collagen membranes (SUCRA rank 81.8%) performed best in vertical buccal height (VBH), autogenous soft tissue grafts (SUCRA rank 89.1%) in horizontal width change (HWch), and control (SUCRA rank 85.8%) in keratinized mucosa thickness (KMT).

Conclusions

NMA confirmed that the use of crosslinked collagen membranes and autogenous soft tissue grafts represented the best choices for sealing sockets during ARP in terms of minimizing post-extraction soft tissue dimensional shrinkage.

Clinical relevance

Grafting materials demonstrated statistically significantly better performances in terms of soft tissue thickness and vertical buccal height changes, when covered with crosslinked collagen membranes. Instead, soft tissue grafts performed better in horizontal width changes. Non-crosslinked membranes and other materials or combinations presented slightly inferior outcomes.

Methods and parameters for digital evaluation of gingival recession: a critical review

OBJECTIVES

The aim of the present review was to find, compare, and critically discuss digital methods for quantitative evaluation of gingival recessions dimensions.

DATA

Collection of articles and classification related to digital evaluation of gingival recessions.

SOURCES

A search of PubMed, Web of Science, Scopus, and reference lists of articles was conducted up to April 2021 STUDY SELECTION: Twenty-two articles used digital evaluation of gingival recessions dimensions. The methods in the included articles were extracted, compared, and categorized.

RESULTS

Digital measurements were performed on 2D intraoral photographs, 3D models, or cross-sections obtained from 3D models. Baseline measurement were performed for diagnostic and treatment planning and categorised into distance and area measurements. Follow-up evaluation of treatment was based either on repeating the "baseline" measurements and calculating differences or measuring differences directly on composite images, composed from two superimposed images obtained at two time-points. Direct measurements were categorised into distance, area, and volume measurements.

CONCLUSIONS

Digital evaluation predominantly means just digitalization of the established evaluation methods; therefore, increasing measurements accuracy and maintaining comparability with past studies. At present, a large variability of digital evaluation workflow among the included studies renders the comparison among different studies difficult if not impossible. The potential of digital evaluation seems not to have been fully exploited as only a few novel measurements and parameters introduced, i.e., volumetric evaluation of soft tissue dynamics. For reproducible and comparable studies in the future, the research should be aimed at evaluation, optimization and standardization of all phases of the digital evaluation.

CLINICAL SIGNIFICANCE

Digital evaluation, based on 3D image superimposition is a promising approach as it increases measurements accuracy, maintains compatibility with past studies and simultaneously introduces novel evaluation possibilities.

Effect of alveolar ridge preservation on clinical attachment level at adjacent teeth: A randomized clinical trial

PURPOSE

To test whether or not alveolar ridge preservation (ARP) changes the clinical attachment level (CAL) at adjacent teeth of extraction sockets after 6 months.

MATERIAL AND METHODS

Seventeen patients requiring bilateral tooth extractions of the upper molars were recruited. After tooth extraction, the sockets were randomly allocated to two groups applying a split-mouth design: (1) ARP using deproteinized bovine bone mineral containing 10% collagen (DBBM-C) covered by a collagen membrane and (2) spontaneous healing (control). CAL, probing pocket depth (PD), bleeding on probing (BOP), gingival recession (REC), and bone levels were evaluated at the adjacent teeth of the extraction sockets at baseline and after 6 months of follow-up.

RESULTS

A total of 14 patients were available for reexamination. From baseline to 6 months of follow-up mean CAL changes of all six sites at adjacent teeth of the extraction sockets amounted to -0.23 ± 0.65 mm (gain) in ARP group and 0.05 ± 0.86 mm (loss) in the control group with significant differences in favor of ARP (p = 0.04). The CAL gain was significantly more favorable at mesiopalatal sites (p = 0.01). Consistently, the mean reduction of PD of all six sites amounted to -0.68 ± 0.84 mm in ARP and -0.34 ± 0.74 mm in the control group (intergroup p = 0.02). The PD reduction was significant (p = 0.001) at the mesiopalatal sites in ARP. BOP, REC, and bone levels showed no significant differences between the groups (intergroup p > 0.05).

CONCLUSION

Although ARP with DBBM-C revealed a trend toward CAL gain and PD reduction at adjacent teeth of extraction sites, these adjunctive benefits seem to be clinically negligible.

Effect of customized healing abutments on the peri-implant linear and volumetric tissue changes at maxillary immediate implant sites: A 1-year prospective randomized clinical trial

BACKGROUND

Immediate implant placement (IIP) associated with the use of bone substitutes and collagen matrices (CM) seems to reduce the amount of resorption at peri-implant areas. Recently, customized healing abutments (CA) appeared as another solution in order to seal the socket and preserve the original soft tissue contour.

PURPOSE

To evaluate peri-implant tissues dimensional changes after using customized healing abutments compared with the use of xenogeneic collagen matrices as socket sealing options in flapless maxillary immediate implant placement.

MATERIAL AND METHODS

The present study was designed as a prospective, randomized, controlled clinical trial. Patients were allocated into two groups depending on the socket sealing option: in the CM group a collagen matrix was used and in the CA group a customized abutment. Digital impressions were taken prior to extraction, 1, 4, and 12 months after implant insertion and the digital files allowed to evaluate linear buccal changes (MBC) and the buccal volumetric variation (BVv) between the different time points at peri-implant tissue areas. Additionally, mucosa variation was computed assessing the papilla presence and the midfacial mucosa height. Statistical significance was set at 0.05.

RESULTS

Twenty-eight patients were observed during a 12-month period. Significant differences between mean values of BVv at the first month were observed at the CM and CA group (-9.75 ± 6.65% and -4.76 ± 5.29%, respectively) (p = 0.043). At the 1-year follow-up, no significant differences were found in terms of BVv between the two groups, although the thin bone phenotype (≤1 mm) significantly influenced the volumetric variations that occurred in each group. No significant differences were noticed in midfacial mucosa and papillae alteration between groups, after 1 year of treatment.

CONCLUSION

Both treatment options are predictable solutions for socket sealing in IIP, although a higher volumetric variation can be expected in the presence of thin bone phenotypes.

The question about the numerical value and quantitative data transfer of implant prosthodontics-orom experience guidance to digital guidance

The correct implant site design and placement are the basic clinical techniques that must be known for implant restoration. For a long time, most implants have been placed by free hands, and the choice of site is mostly dependent on the accumulation of long-term experience of the surgeon. The selection of implant site guided by this experience analogy logic is often based on the surgeon's level of experience,which often makes it very easy to produce complications related to the implant restoration of the incorrect site. In contrast, a clinical program using digital guidance and real-time measurable verification has emerged based on the restoration-oriented implantation concept, which marks the formation of an accurate, measurable and verifiable whole-process digital implant prototype. Furthermore, from the perspective of surveying, the numerical requirements that digital implant restoration relies on are actually incomplete to the four elements of measurement, which leading to the doubts about its authenticity. This article will question the numbers in implant restoration, and conduct a preliminary demonstration, and propose a new reliable actual measurement and verification method of the correct location and the numerical requirements of the restoration space and a new clinical program that relies on numbers from the perspective of the evolution of digital restoration, guided implantology and actual measurement technology. And this article further discusses the current mainstream implant restoration technology based on experience analogy which cannot effectively support the whole process of digital implant restoration and provides a new logical cognitive basis for the final realization of the entire process of digital implant restoration.

Immediate implant placement in fresh alveolar sockets with a minimal split-thickness envelope flap: A randomised controlled clinical trial

OBJECTIVES

Comparing PES/WES scores, modified success rate, survival, success, buccal bone thickness and patient-reported outcomes of immediate dental implants placed in fresh alveolar sockets using a flap or a minimal split-thickness envelope flap (MSTEF).

MATERIALS AND METHODS

Implants following random assignment into a flap or MSTEF group were placed immediately in anterior and premolar areas. Guided bone regeneration and autogenous connective tissue graft were used in all cases. A temporary prosthesis was provided followed by the final prosthesis at 16-18 weeks. Success and survival rates together with radiographic buccal bone thickness and patient satisfaction were evaluated at 12-month post-loading. The aesthetic outcome was evaluated through the Pink (PES) and White (WES) Aesthetic Score by 8 blind clinicians of different training background and incorporated in modified success criteria.

RESULTS

28 implants were placed on 28 patients. No statistically significant differences were noted in PES (10.54 control versus 10.80 test), WES scores (6.97 control versus 6.95 test) or success criteria including aesthetic parameters (modified success criteria) for the different specialty groups (Range 69%-92%). In addition, no statistically significant differences were noted in survival (100%), success (100%), buccal wall thickness between control (0.72 ± 0.22) and test group (0.92 ± 0.31) and patients' reported outcomes.

CONCLUSIONS

Immediate dental implant treatment with flap/ MSTEF provided similar mean PES/WES scores, modified success rate, survival, mean buccal bone levels and patients' satisfaction. However, aesthetic failures were common in both groups.

Socket shield technique: A systematic review of human studies

BACKGROUND AND PURPOSE

Alveolar bone resorption after dental extraction frequently leads to situations in which long-term function and esthetic success of rehabilitations with dental implants is a challenge. Socket shield has been described as an alternative technique to maintain the alveolar ridge when placing immediate implants. The aim of this review is to evaluate the medium- and long-term clinical outcomes of the socket shield technique in human studies.

MATERIAL AND METHODS

This review was conducted according to PRISMA guidelines. An electronic search was conducted in four databases: (1) The National Library of Medicine (MEDLINE/PubMed) via Ovid; (2) Web of Science (WOS); (3) SCOPUS; and (4) Cochrane Central Register of Controlled Trials (CENTRAL). The Cochrane Collaboration tool, the Newcastle-Ottawa Quality Assessment Scale and The Joanna Briggs Institute Critical Appraisal tool were used to assess the quality of evidence in the studies reviewed.

RESULTS

Six articles were included in this review. The studies analysed showed lower rates of horizontal and vertical alveolar bone resorption, better maintenance of the buccal plate, less marginal bone loss and better esthetic results than simple placement of immediate implants. However, a lack of homogeneity was found in evaluation methods of the different outcomes, surgical procedures and prosthetic management.

CONCLUSIONS

Based on the results of this review, it is possible to suggest that socket shield technique could be a good alternative in terms of alveolar bone maintenance, marginal bone stability and aesthetic outcomes in immediate implant treatment. However, it is not possible to recommend this technique as an alternative treatment with the same long-terms predictability as conventional immediate implants.

Comparison of the soft and hard peri-implant tissue dimensional changes around single immediate implants in the esthetic zone with socket shield technique versus using xenograft: A randomized controlled clinical trial

OBJECTIVE

Compare the dimensional changes of the peri-implant soft and hard tissues clinically and radiographically around single immediate implants in the esthetic zone with socket shield technique versus filling the buccal gap with xenograft.

MATERIALS AND METHODS

Forty-two patients with a single non-restorable tooth in the esthetic zone replaced with an immediate implant were randomly assigned either to the socket shield technique (test) or to grafting the buccal gap with xenograft (control). The vertical and horizontal buccal bone resorption were measured 6-months following implant placement. The esthetic outcomes were evaluated by assessing the Pink Esthetic Score (PES) and the amount of midfacial mucosal alteration, in addition to patient satisfaction assessment through a Visual Analogue Scale (VAS) based questionnaire 1-year following implant restoration.

RESULTS

The present study showed that the socket shield group yielded significantly less vertical and horizontal buccal bone resorption of 0.35 (±0.62) mm and 0.29 (±0.34) mm compared to 1.71 (±1.02) mm and 1.45 (±0.72) mm in the xenograft group respectively. Also, there was a significantly greater midfacial mucosal recession in the xenograft group of 0.466 (±0.58) mm compared to midfacial mucosal coronal migration of 0.45 (±0.75) mm in the socket shield group. However, there was no statistically significant difference regarding the total PES and patient satisfaction in both treatment groups.

CONCLUSION

The socket shield technique can preserve hard and soft peri-implant tissues following immediate implant placement. (ClinicalTrials.gov Identifier: NCT03684356).

Aesthetic outcomes of non-functional immediately restored single post-extraction implants with and without connective tissue graft: A multicentre randomized controlled trial

OBJECTIVES

To compare the 1-year aesthetic results of flapless single implants, placed in fresh extraction sockets with bone replacement and immediate provisional restoration with or without a connective tissue graft (CTG).

MATERIAL AND METHODS

The present study proposes a partially blinded multicentre parallel randomized controlled trial, where computer-generated tables were used for central randomization to allocate treatments. A total of 59 of the 60 patients screened by eight private practices in Northern Italy fulfilled the inclusion criteria. Immediate implants were placed in a fresh extraction socket with a non-functional immediate provisional restoration with (Test group) or without (Control group) a CTG. The primary outcome variable was the implant Crown Aesthetic Index (ICAI) at the 1-year follow-up.

RESULTS

ICAI for the 59 randomized patients (Test group = 31, Control group = 28) at the 1-year follow-up was 4.69 (95% CI = 3.16-6.22) for the Test group and 3.45 (95% CI = 1.83-5.08) for the Control group, without statistically significant difference between the two groups (p = .086). One implant failure was recorded in each group, resulting in an implant survival rate of 96.8% [95% CI = 83.3-99.9] for the Test group and 96.4% [95% CI = 81.7-99.9] for the Control group. Other secondary outcome variables and complication rates were comparable across the two groups.

CONCLUSIONS

Within the limitations of the present clinical trial, the results suggested that the adjunct use of CTG is not mandatory to achieve successful aesthetic outcomes for a well-planned immediate implant placement with immediate non-functional provisional restoration in a fresh extraction socket.

Facial alveolar bone thickness and modifying factors of anterior maxillary teeth: a systematic review and meta-analysis of cone-beam computed tomography studies

Background

Understanding the anatomy of the facial alveolar bone (FAB), provides a prognostic tool for estimating the degree of dimensional ridge alterations after tooth extraction. This systematic review and meta-analysis aims to determine the FAB thickness and modifying factors of anterior maxillary teeth measured by CBCT scans. A secondary objective was to assess the facial distance from the cementoenamel junction (CEJ) to the bone crest.

Methods

An electronic search was made of Medline, Embase, Web of Science, Cochrane Library and Google Scholar up to December 2019. Studies that analyze and quantitatively compare FAB thickness at maxillary teeth by CBCT scans were included. The methodological quality of the included studies was appraised using the ROBINS-I tool and the overall meta-evidence certainty using the GRADE approach. A single means random-effects meta-analysis was performed to obtain the weighted mean for 95% confidence interval. A meta-regression of covariates and subgroup analysis was conducted. The nullity Q_h test and I² index for heterogeneity was estimated.

Results

2560 potentially relevant articles were recorded from which 29 studies were selected for the qualitative analysis, including 17,321 teeth. Seventeen studies considered the facial bone crest, and 12 the CEJ as a reference point for their measurements. Mean FAB thickness was ≤ 1 mm in maxillary incisors and canines (0.75–1.05 mm) and 1–2 mm in premolars. Patients over 50 years of age, females and thin gingival phenotype was associated with thinner FAB at some apico-coronal locations of maxillary incisors and canines. The geographical setting was an effect modifier that could explain up to 87% of the heterogeneity in FAB thickness, being Asian populations that showed the lowest FAB thickness values. The CEJ-bone crest distance was 2–2.5 mm in all teeth analyzed. Population over 50 years of age exhibited greater CEJ-bone crest distances, and males also showed a trend for greater distance. Evidence certainty has shown moderate quality in most analysis subsets.

Conclusions

Facial alveolar bone at anterior maxillary teeth is thin, heterogeneous in width along its apico-coronal dimensions, and increases in thickness in maxillary premolars. The CEJ-bone crest distance presented homogeneous and similar values in all teeth analyzed.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12903-021-01495-2.

Terminal dentition to functional esthetic full-mouth implant reconstruction: Evidence-based approach

Implant-supported fixed dental prosthesis is a well-accepted treatment option for edentulism. Loss of teeth due to extensive caries or severe periodontitis presents a challenge to the clinicians. Young age disability with either of these problems can further make full-mouth rehabilitation on implants a complex procedure. The outcome of implant surgery with periapical infections and periodontal inflammation is unpredictable and often delays the placement of dental implants. Here, we describe a case of full-mouth reconstruction with implant-supported prosthesis in a young individual who lost all her teeth due to extensive caries. The journey from terminal dentition to functional esthetic rehabilitation was uneventful.