Faculty Bibliography

AIM AND OBJECTIVE/OBJECTIVE:The aim of this paper is to ascertain the quantitative measurements of alveolar bone thickness at all maxillary anterior teeth and qualitatively demonstrate the relationship between tooth angulation (TA) and alveolar bone thickness. MATERIALS AND METHODS/METHODS:Cone-beam computed tomography (CBCT) images of 189 maxillary anterior teeth were collected. Sagittal view was selected to perform the measurement on alveolar bone wall at crestal, midlevel, and palatal. TA was measured along to the tooth long axis (TLA) related to the alveolar bone housing. Spearman's correlation coefficients were conducted to test the correlation between the variables. RESULTS:= 0.478). CONCLUSION/CONCLUSIONS:The FAB wall crest of maxillary anterior teeth was generally thin and not gradual with the lateral incisor being the thinnest. A significant correlation of TA existed based on different types of maxillary anterior teeth and alveolar bone level. The maxillary anterior teeth with increased buccolingual angulation were correlated with thicker bone at the apical level. CLINICAL SIGNIFICANCE/CONCLUSIONS:The quantitative assessment of FAB and TA in degree may serve as an anatomical index for ideal implant position.

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.

Achieving primary stability is a critical challenge presented by immediate implant therapy. Surgeons often utilize wider, tapered implants for this purpose, or they use longer implants to achieve primary stability. Both strategies are associated with negative ramifications. Prosthetically guided implant placement must respect biologic principles, such as tooth-implant and implant-implant distance, gap space between the implant and the facial cortex, and, when possible, screw-retention of the prosthesis. A novel implant design geared toward achieving a predictable level of primary stability while adhering to the aforementioned physiologic principles was recently introduced. Both primary and secondary implant stability, along with hard and soft tissue stability, are demonstrated in this study of 107 consecutively placed implants. Rotational and axial stability can be produced with this newly designed implant, along with predictable osseointegration and tissue preservation.

A clinical case series of three patients is presented using a novel implant design to not only address primary stability but also to prevent damage to the labial bone plate and improve the interdental space for papillae preservation with immediate tooth replacement therapy. This unique implant design features an apicocoronal inverted body-shift in diameter (wide to narrow), shape (tapered to cylindrical), thread depth (deep to shallow), and thread pattern (V-shaped to square) to achieve uncompromised primary stability and esthetics, particularly in extraction sockets, in a singular body form. In addition, the implant possesses a prosthetic angle correction within the implant body to facilitate screw-retention of the restoration and avoid the risk of apical socket perforation.

A case report of tooth agenesis and excessive intraarch space due to tooth size discrepancies and malformed teeth is presented. Interdisciplinary treatment including orthodontics, implant surgery, prosthodontics, and laboratory fabrication with dissimilar restoration and material types was used to accomplish an esthetic and functional outcome. Proper diagnosis of individual tooth width and proportion were key elements in treatment. CLINICAL SIGNIFICANCE: Knowledge and understanding of the relationships of the mandibular to maxillary anterior teeth and shade management of dissimilar restoration types will allow the interdisciplinary team to achieve the desired esthetic restorative result.

OBJECTIVE:The following is a clinical report addressing when to save or remove implants with esthetic deficiencies in the smile zone as well as the sequence and timing of interdisciplinary treatment. CLINICAL CONSIDERATIONS/UNASSIGNED:Key factors in the decision-making process in treating implants in malposition are whether the implants are (1) in a reasonable restorative position, (2) free of disease, and (3) placed with adequate depth. This clinical report encompassed periodontal corrective surgery, non-surgical soft tissue sculpting through subgingival crown contour, material selection for definitive restorations, and cementation techniques for cement-retained restorations. CLINICAL SIGNIFICANCE/CONCLUSIONS:Knowledge and understanding of interdisciplinary treatment planning, sequencing, and respective techniques that can be implemented when confronting implants in malposition in the smile zone will allow the interdisciplinary team to achieve the desired esthetic restorative result.

There is a need to modify the definition of attached gingiva (AG) as it applies to healthy and diseased teeth and implants. There are two parts to this new definition: Part A is when the biologic width is supracrestal (epithelial attachment and gingival fibers) and is attached to a healthy tooth or tissue-level implant, and the zone of AG is measured from the base of the sulcus to the mucogingival junction (MGJ); Part B is when the biologic width is subcrestal-as with infrabony defects on periodontally involved teeth, periodontally involved tissue-level implants, and bone-level implants placed at or below the bone crest-and the zone of AG is measured from the bone crest (not the base of the sulcus) to the MGJ. Further, what the AG is actually attached to around teeth and different types of implants, and the clinical significance of these differences, are thoroughly discussed.

Immediate tooth replacement therapy (ITRT), ie, immediate implant placement and provisional restoration in postextraction sockets, has been shown to achieve favorable outcomes in reference to soft tissue stability and esthetics. However, avoiding socket perforation with uniaxial implants in the anterior maxilla can be challenging due to the inherent anatomy. Dual or co-axis subcrestal angle correction (SAC) implants have been developed to change the restorative angle of the clinical crown restoration subcrestally at the implant-abutment interface to enhance the incidence of screw-retained definitive restorations. An additional benefit of this macrodesign implant feature is variable platform switching (VPS) that increases soft tissue gap distance above the implant platform. The purpose of this prospective study on ITRT in maxillary anterior postextraction sockets was to investigate the effect of SAC with VPS (SAC/VPS) compared to conventional platform-switch-design implants (PS) relative to ridge dimension stability and peri-implant soft tissue thickness. A total of 29 patients had undergone ITRT and received either a PS or SAC/VPS implant; previously described measurements were made compared to the contralateral natural tooth sites. When the comparison of buccal soft tissue thickness was made, SAC/VPS showed a greater increase compared to PS (3.12 mm vs 2.39 mm, respectively) with statistical significance (P = .05). The increase was independent from periodontal phenotype. Therefore, SAC/VPS may increase peri-implant soft tissue thickness and help minimize recession following ITRT.

Immediate tooth replacement therapy (ITRT) in the maxillary anterior sextant is an increasingly frequent treatment option sought by patients and performed by clinicians worldwide. Achieving long-term results that are predictable, stable, esthetic, and healthy is the ultimate goal. This trend also lends itself to minimally invasive surgery as well as defining the procedure to a singular surgical intervention. Preserving and augmenting hard and soft tissues at the time of immediate implant placement provides the best opportunity to achieve these goals. Incorporating an implant with a subcrestal angle correction [SAC] or biaxial feature facilitates screw-retention of both provisional and definitive restorations through the cingulum portion of the crown. Compared to uniaxial implants, these implants also feature an extended or variable platform switch [VPS] facially. Measurements of the peri-implant soft tissue thickness 2.0 mm apical to the facial free gingival margin were compared between two groups of 15 consecutively treated patients with different implant designs to evaluate the effect of SAC/VPS for ITRT. The null hypothesis was that there is no difference between uniaxial and biaxial implants with bone grafting and dermis allograft. These authors contend that using a combined hard and soft tissue grafting approach along with SAC/VPS biaxial implants has a synergistic effect on increasing peri-implant soft tissue thickness compared to uniaxial implants.

BACKGROUND:A retrospective comparative radiographic and clinical studywas performed to evaluate primary stability, bone volume, and esthetic outcomes of tapered (T) implants (control group) versus inverted body-shift (INV) implants (test group). METHODS:A total of 42 platform-switched implants, 21 T and 21 INV, were used to replace nonrestorable teeth in maxillary central incisor post-extraction sockets. Implant primary stability and insertion torque values in addition to radiographic differences in labial plate dimension, tooth-to-implant distance, and marginal bone levels were correlated with clinical outcomes using the pink esthetic score (PES). RESULTS:Statistically significant differences (P ≤ .05) were found between groups, with T implants having not only lower primary stability at immediate implant placement than INV implants but also less circumferential bone volume at recall. Consequently, lower PESs were seen in the T implant group that equated to an increased frequency of midfacial recession, tissue discoloration, and papilla loss. CONCLUSIONS:INV implants, which feature a unique macro hybrid design, may offer advantages over T implants in maxillary anterior post-extraction sockets with regard to achieving both higher primary stability and superior esthetic outcomes.