Surgical crown lengthening: a 12-month clinical wound healing study

Pre-restorative crown lengthening surgery: influence of restorative treatment timing on clinical outcomes-a pilot study

OBJECTIVES

Aim of this study was to assess the influence of restorative treatment timing on the periodontal, patient and operator-reported outcomes following crown lengthening surgery (CLS).

MATERIALS AND METHODS

Eighteen study participants requiring CLS were divided into two groups based on prosthetic rehabilitation timing (6 or 14 weeks postoperatively). Clinical parameters were recorded around treated and neighboring teeth before and after surgery, 6 and 14 weeks postoperatively, at prosthesis delivery, and three and six months after. Soft tissue and radiographic bone changes were evaluated. Patients assessed their perception of the procedure by means of a questionnaire. The final treatment outcome was rated by both patients and prosthodontists.

RESULTS

CLS resulted in statistically significant and stable apical displacement of the gingival margin, at both treated and adjacent sites. Plaque and bleeding scores remained low throughout. No statistically significant differences were observed between groups for any clinical or radiographic parameter examined. Healing was uneventful and treatment outcome was satisfying for both patients and prosthodontists, without statistically significant differences between groups.

CONCLUSIONS

The present study has been characterized as pilot, because it was not possible to reach the sample size indicated by the a priori power analysis. CLS is an effective pre-prosthetic procedure as long as it is performed under a certain surgical protocol which predicts for at least a 3 mm distance between bone crest and the flap margin at suturing. Within the limitations of this study, six weeks after surgery may be an adequate healing time for the onset of prosthetic restoration.

CLINICAL RELEVANCE

Crown lengthening surgery is commonly performed in daily clinical practice with the aim to restore teeth with short clinical crowns. Based on periodontal, patient and operator-reported criteria, 6 weeks after CLS may be adequate healing time before the onset of prosthetic restoration.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03947658, 13/05/2019, retrospectively registered.

Dental and periodontal dimensions stability after esthetic clinical crown lengthening surgery: a 12-month clinical study

OBJECTIVES

To evaluate the stability of periodontal tissues 3 (T3), 6 (T6), and 12 (T12) months after esthetic crown lengthening (ACL) and the possible correlations between changes in those structures.

MATERIALS AND METHODS

Twenty individuals were evaluated through clinical assessment, photography, and tomography. Measurements included gingival margin (GM), clinical crown length (CCL), interdental papilla height (PH) and width (PW), gingival thickness (GT), bone thickness (BT), probing depth (PD), distance between alveolar crest and GM, distance between alveolar crest and cementoenamel junction. Nonparametric and correlation statistics were performed (p < 0.05).

RESULTS

CCL at T0 was 7.42 ± 0.70 mm and increased to 9.48 ± 0.49 mm immediately after ACL, but it decreased to 8.93 ± 0.65 mm at T12. PD decreased 0.60 mm from T0 to T6, and it increased 0.39 mm from T6 to T12. BT decreased 0.20 mm, while GT increased 0.29 mm from T0 to T12. Both PW and PH showed enlargement in T12. A positive moderate correlation was found between CCL/T0 and CCL/T12, GT/T0 and AC-GM/T12, BT/T0 and GT/T12. A few negative moderate correlations were PD/T0 and CCL/T12, PD/T0 and PH/T0, PD/T0 and BT/T12.

CONCLUSIONS

ACL procedure was effective. Although some rebound occurred, that was not clinically important. PD tended to reestablish its original length, partially due to a migration of GM during the healing period. Besides, a thickening of supracrestal soft tissues was observed.

CLINICAL RELEVANCE

The present study centers on the factors influencing the stability of periodontal tissues after esthetic crown lengthening, underscoring the procedure's influence on esthetics and biology and the need for careful treatment planning.

Accuracy of three types of digital guides for crown lengthening surgery: An in vitro study

Background/purpose

The guided protocols always yield a higher accuracy than freehand surgery. However, the accuracy of digital guides for crown lengthening surgery (CLS) is unknown. The purpose of this study was to evaluate the trueness of 3 types of digital guides for CLS.

Materials and methods

Twenty individually designed maxillary models were divided into 4 groups according to surgical guides: type I (T1), type II (T2), type III (T3), and free-hand. T1 comprised a planed gingival margin at the tissue level. T2 included both the planed gingival margin and alveolar crest at the tissue level. T3 consisted of a planed gingival margin at the tissue level and an alveolar crest at the bone level. CLS was performed under the indication of the guides. Trueness of the guides was evaluated through the deviation of the gingival zenith and alveolar crest height.

Results

The control group had higher vertical and horizontal distance deviations of gingival zenith compared to the 3 digital guide groups (P < 0.001). There were no significant differences among the 3 test groups in terms of gingival zenith deviations (P > 0.05). With regard to height deviation of alveolar crest, the control and T1 groups were higher than T2 group (P < 0.001), while T3 group had the lowest deviations among the 4 groups (P < 0.001).

Conclusion

The digital guides assisted CLS procedures are more accurate than free-hand method. The trueness of type III guide was better than type I and type II.

Staged esthetic crown lengthening: Classification and guidelines for periodontal-restorative therapy

OBJECTIVE

This article presents technical guidelines for perio-restorative esthetic crown lengthening, along with a discussion of the biologic rationale. A classification system is proposed to assist in treatment planning and sequencing the surgical and restorative phases.

CLINICAL CONSIDERATIONS

When esthetic crown lengthening is performed as an adjunct to restorative therapy, the surgical approach must be determined by the anticipated position of the restorative margins. The removal of sufficient bone to achieve the desired clinical crown length and preserve the supracrestal gingival tissue dimensions is facilitated by the use of a surgical guide fabricated according to the design of the restorations. A staged approach allows sequencing the provisional restoration to minimize unesthetic sequelae during the healing period. Inadequate bone resection and/or alteration of the soft tissue dimensions results in delayed healing, leading to coronal gingival rebound and biologic width impingement.

CONCLUSION

The identification and preservation of appropriate restorative and biologic landmarks is essential for success in pre-prosthetic esthetic crown lengthening treatment. A staged approach improves the esthetic management during the postsurgical healing and maturation period.

CLINICAL SIGNIFICANCE

A restorative driven classification system for sequencing and staging adjunctive esthetic crown lengthening procedures is presented. Technical guidelines to enhance gingival margin predictability are suggested, accompanied by relevant evidence. In addition, wound healing timelines following gingival and osseous resection are provided.

Effects of the GingivalStat approach on early gingival margin remodeling following esthetic clinical crown lengthening: A case series

OBJECTIVES

The aim of this case series is to present the potential applications of the GingivalStat approach, that is, the use of temporary gingival stabilizers, to favor early gingival margin remodeling and prevent the occurrence of gingival rebound following esthetic clinical crown lengthening.

CLINICAL CONSIDERATIONS

Four patients requiring clinical crown lengthening were treated for esthetical and functional reasons. The surgical approach included: (a) gingival margin recontouring; (b) full-thickness flap elevation; (c) osteotomy (to achieve an adequate dimension between the alveolar bone crest and the CEJ) and osteoplasty (to reduce the bone thickness and improve the buccal bone anatomic profile, where indicated); (d) temporary gingival stabilizer placement using a block-out resin or a composite (the GingivalStat approach); and (e) flap repositioning, adaptation, and suture. One- to five-year follow-ups, reported in the different case scenarios, show evidence of clinically stable gingival margins around the treated teeth.

CONCLUSIONS

Within the limits of this case series, it can be concluded that the GingivalStat approach appears as a further maneuver to cope with clinical crown lengthening procedures at esthetic sites. GingivalStat seems to favor gingival margin contour remodeling during the early phase of healing as well as prevent the occurrence of gingival rebound.

CLINICAL SIGNIFICANCE

GingivalStat approach may guide gingival margin remodeling and prevent gingival rebound after wound healing of sites submitted to esthetic clinical crown lengthening.

Biological evaluation of indirect restorations in endodontically treated posterior teeth with deeply located proximal margins following deep margin elevation versus surgical crown lengthening: a randomized controlled trial

OBJECTIVE

The current clinical trial was conducted to evaluate the effect of proximal indirect restorations in endodontically treated posterior teeth with deeply located margins following deep margin elevation compared to surgical crown lengthening.

MATERIAL AND METHODS

Deep proximal cavities in endodontically treated posterior teeth were randomly assigned into two groups; deep margin elevation (DME) or crown lengthening (CL). The clinical attachment level (CAL), probing depth (PD), bleeding on probing (BOP), crestal bone level (CBL), and secondary caries were evaluated at the baseline, 1, 3, 6, 9, and 12 months.

RESULTS

A total of 20 proximal cavities were included in the study; there was no significant difference between the two groups regarding mean CAL values at the baseline and 1 month, while there was a significant difference between the two groups in all other periods. Regarding the PD, there was no statistical significance between the two groups except at 9 and 12 months, where CL showed higher mean PD values than DME. There was no statistically significant difference in BOP or CBL between the two groups.

CONCLUSIONS

DME and CL are considered clinically successful with favorable biologic responses.

CLINICAL RELEVANCE

The deep margin elevation approach could provide a more conservative solution when relocating deeply seated cervical margins in a more coronal position. DME reduced the number of visits and time needed for the restoration of endodontically treated teeth. Surgical crown lengthening remains a gold standard procedure in the re-establishment of the supracrestal tissue attachment, especially in cases where cervical margins are beyond the elevation capacity.

Multifunctional anatomical prototypes (MAPs): Treatment of excessive gingival display due to altered passive eruption

OBJECTIVE

To describe a strategy using digital technologies for improving the diagnosis, treatment planning, and surgical execution of patients with excessive gingival display (EGD) due to altered passive eruption (APE).

CLINICAL CONSIDERATIONS

An important component for successful patient's management is to fulfill their esthetic expectations whilst delivering predictable and long-term therapeutic outcomes. To achieve this goal in patients with excessive gingival display due to altered passive eruption, it is essential to perform an accurate diagnosis and to communicate to the patient the expected customized results using digital technologies. Computer-aided designed and manufactured multifunctional anatomical prototypes (MAPs) may contribute to these purposes. Additionally, they can guide the surgical crown lengthening procedure or serve as a reference during the surgical guide fabrication providing information of the required anatomical landmarks.

CONCLUSIONS

This novel strategy protocol for diagnosis, communication, and treatment management of patients with excessive gingival display follows functional and biological principles within the frame of a digital workflow, which improves the diagnostic capabilities, enhances communication, and guides the surgical treatment as shown in the 12 months follow-up of the reported case.

CLINICAL SIGNIFICANCE

Developing a virtual patient by combining multiple digital data sets including cone-beam computed tomography (CBCT), intra-oral scans and digital photography, supports the clinician and the patient to achieve a comprehensive diagnosis and to better communicate the expected results to the patient. Furthermore, this digital treatment exercise based on anatomical and biological principles will facilitate the surgical precision and the achievement of successful outcomes, thus fulfilling the patient needs and expectations.

Forced surgical extrusion using an axial tooth extraction system as a practicable technique for preserving severely destroyed teeth? - Clinical outcomes up to 4.8 years

OBJECTIVE

Several extrusion techniques have been described to restore teeth with insufficient coronal tooth structure and to avoid their extraction. Still, there is little evidence for a treatment concept combining surgical extrusion using an atraumatic axial extraction system.

MATERIALS AND METHODS

A total of nine patients, each with an iso- or subgingival fractured tooth, were retrospectively examined. Treatment of the damaged tooth comprised an atraumatic forced surgical extrusion performed with an axial tooth extraction system and a more coronal positioning within the socket. The teeth were initially splinted and subsequently restored. The follow-up period was up to 57.1 months and averaged 36.5 (SD: ±13.5) months.

RESULTS

All nine teeth were still in situ, without signs of inflammation. During the period of the provisional restoration, six prosthetic complications occurred, which were resolved with little effort, whereas, success rate for the definitive restoration was 100%. No biological complications were observed concerning the root apex or soft tissue. The radiographically measured mean extrusion distance was 3.4 (SD: ±1.0) mm, so that a sufficient prosthetic ferrule could be reestablished.

CONCLUSIONS

Surgical extrusions using an axial tooth extraction system demonstrate low biological and prosthetic complications rates over observation time.

CLINICAL SIGNIFICANCE

The presented extrusion approach preserves soft and hard tissue and is an efficient treatment option for severely destroyed teeth. Saving hopeless teeth by this relatively predictable and feasible procedure has hardly any disadvantages for patients, and in case of failure, an implant or fixed partial denture are still an option.

The clinical use of computer aided designed/computer aided manufactured titanium nitride coated implant abutments: Surgical and prosthetic considerations-A case series

OBJECTIVE

To describe the clinical use of nitride-coated titanium CAD/CAM implant abutments in the maxillary esthetic zone in two patients with high esthetic and functional demands and, to highlight the advantages of nitride-coated milled titanium abutments when compared to stock/custom titanium, one-piece monolithic zirconia, and hybrid metal-zirconia implant abutments.

CLINICAL CONSIDERATIONS

Due to the inherent mechanical and esthetic clinical challenges, single implant-supported reconstructions in the maxillary esthetic zone are a complex restorative treatment. While CAD/CAM technology has been suggested to enhance and ease implant abutment design and manufacturing, implant abutment material selection remains as a critical decision affecting restoration's long-term clinical outcomes. To date, considering the esthetic disadvantages of conventional titanium implant abutments, the mechanical limitations of one-piece zirconia abutments and the manufacturing time and costs associated with hybrid metal-zirconia abutments, no abutment material can be considered "ideal" for all clinical scenarios. Due to their biocompatibility, biomechanical characteristics (hardness and wear resistance), optical properties (yellow color), and peri-implant soft tissue esthetic integration, the use of CAD/CAM titanium nitride-coated implant abutments has been suggested as a predictable implant abutment material in mechanically challenging but esthetically demanding clinical situations, as the maxillary esthetic zone.

CONCLUSIONS

Two patients requiring a combined tooth-implant restorative treatment in the maxillary esthetic zone were treated using CAD/CAM nitride coated titanium implant abutments. The principal advantages of TiN coated abutments include comparable clinical outcomes to stock abutments, optimal biocompatibility, adequate fracture, wear, and corrosion resistance, reduced bacterial adhesion, and excellent esthetic integration with adjacent soft tissues.

CLINICAL SIGNIFICANCE

Clinical reports and short term mechanical, biological and esthetic clinical outcomes indicate that CAD/CAM nitride coated titanium implant abutments can represent a predictable restorative alternative to stock/custom and metal/zirconia implant abutments and be considered a clinical relevant option in mechanically challenging but esthetically demanding situations, as often found in the maxillary esthetic zone.

Effect of post-surgical flap position on soft tissue regrowth and keratinized tissue increase following fibre retention osseous resective surgery: a 6-month randomized study with multilevel analysis

BACKGROUND

The aim of this randomized split-mouth study was to assess the influence of primary flap position on the amount of coronal soft tissue regrowth and keratinized tissue (KT) 6 months after osseous resective surgery with fiber retention technique (FibReORS).

MATERIALS AND METHODS

Two contralateral posterior sextants in 16 patients were treated with FibReORS and randomly assigned to flap positioning either 2 mm below the bone crest (apical group) or at the level of bone crest (crestal group). Clinical parameters were recorded at 1, 3 and 6 months and patient-related outcomes during the first two post-operative weeks.

RESULTS

Healing period was uneventful. Patient's discomfort was similar in both groups. The overall soft tissue rebound was higher in the apical than in the crestal group (2.0 ± 1.3 mm versus 1.3 ± 0.7 mm), but the difference was statistically significant only interproximally (2.2 ± 1.3 mm versus 1.6 ± 0.8 mm). Multilevel analyses showed higher soft tissue rebound in sites with normal compared to thin phenotype (1.5 mm, p < 0.0001) and treated with flap positioned 2 mm apically to the bone crest (0.7 mm, p < 0.001). An additional 0.5 mm KT increase was observed at interdental sites in the apical group.

CONCLUSIONS

Apical flap positioning increases soft tissue rebound and KT width, mainly at the interdental sites, with reduced patient discomfort.

TRIAL REGISTRATION

The trial was registered at ClinicalTrials.gov (ID: NCT05140681, Registration date: 1/12/2021, retrospectively registered).

Digital planning and guided dual technique in esthetic crown lengthening: a randomized controlled clinical trial

OBJECTIVES

The present study aimed to compare the guided dual technique with the conventional technique in esthetic crown lengthening (ECL).

MATERIALS AND METHODS

The trial registration number is NCT04922086. Twenty-four participants diagnosed with altered passive eruption (APE) type I subcategory B were selected and allocated into two groups. In the control group (n = 12), the ECL procedure was planned by clinical examination and transgingival probing; in the test group (n = 12), the ECL procedure was carried out using digital planning and a double guide. Clinical parameters were assessed at baseline, immediately after the intervention (IAI), and at 4, 8, and 12 months of follow-up.

RESULTS

The clinical crown length (CCL) mean at baseline was 8.09 mm (± 0.77) and increased significantly to 9.92 mm (± 0.62) IAI, with minimal significant reduction after 12 months (9.47 mm [± 0.60]) in the control group. Similarly, in the test group, the mean CCL at baseline was 8.04 mm (± 0.69) and increased significantly to 9.94 mm (± 0.57) IAI, with minimal reduction after 12 months (9.35 mm [± 0.80]). No differences were found between the mean CCL determined in the digital planning and after 12 months. No correlation was found between gingival thickness and gingival margin stability. High esthetic satisfaction was demonstrated by participants/specialists without differences between groups.

CONCLUSIONS

In conclusion, the guided dual technique was as effective as the conventional technique for treatment of APE, with stable results after 12 months of follow-up.

CLINICAL RELEVANCE

The guided dual technique aims to transfer both the gingival and bone resection planned position to facilitate the ECL surgical procedure and increase treatment predictability.

Evaluation of biologic width re-establishment using CHU aesthetic gauges in crown lengthening cases- a clinical study

Background

Present study was performed to assess the biologic width relocation by performing aesthetic crown lengthening with the help of Chu aesthetic gauges.

Methods

The study included 192 teeth from 17 individuals, of which 64 teeth underwent crown lengthening (Treated site- TS) and 128 of which shared a proximal surface (Adjacent site -AS, Non-Adjacent site- NAS) with the surgery site. The clinical parameters Plaque index (PI), gingival index (GI), gingival margin position (PGM), relative attachment level (RAL), bone sounding (BS), biological width (BW), and probing depth (PD) were recorded. The clinical recordings were made at three different times: at baseline, 3 and 6 months post-operatively. Statistical analysis was performed using one way ANOVA and for pair wise comparisons post hoc Tukey test was used. Data was expressed in mean and standard deviations. P < 0.05 was considered statistically significant.

Results

PI and GI showed significant difference (p = 0.000*) at all time intervals. PGM and RAL were significant from baseline to 3 months, baseline to 6 months (p = 0.000*) while non-significance (p > 0.05) was recorded at 3-6 months comparison for PGM, RAL, BS, BW and PD.

Conclusion

Present study concluded that usage of Chu Aesthetic gauges help in controlled removal of soft and hard tissues, biologic width and gingival margin position got stabilized within 3 months and final prosthesis can be advised after 3 months of surgery.

Gingival landmarks and cutting points for gingival phenotype determination: A clinical and tomographic cross-sectional study

BACKGROUND

This cross-sectional study assessed the role of gingival landmarks (GLs) and cutting points (CPs) for gingival phenotype (GP) determination.

METHODS

Six maxillary anterior teeth (70 subjects) were evaluated using soft tissue cone-beam computed tomography (ST-CBCT). Gingival thickness was measured at different GLs: 1) tissue zone (gingival margin [GM], 1 and 2 mm apical to GM, cemento-enamel junction, above the bone crest); 2) bone zone (buccal bone crest [BBC], 1, 2, and 3 mm apical to BBC). CPs of 0.6, 0.8, 1.0, 1.2, and 1.5 mm were used to discriminate between thin and thick GP. The clinical determination of GP was made based on transparency of the periodontal probe (TRAN).

RESULTS

The prevalence of thin and thick GP depended on the GL and CP. Considering the CP (1 mm), thin GP at the tissue zone ranged from 99% at the GM to 10.2% above the bone crest. In the bone zone, thick GP ranged from 28% at the BBC to 6% at 3 mm apical to the BBC. The predictability of a correct assessment of GP by TRAN compared with ST-CBCT was influenced by the GLs and CPs. A slight agreement (kappa <0.2) and low accuracy (area under the curve <0.7) were found between methods.

CONCLUSIONS

The determination of thin and thick GPs is related to the gingival landmarks and CPs. Further studies are required for a well-defined treatment protocol considering different gingival landmarks in tissue and bone zones. An ST-CBCT may be useful for this purpose.

New approach to expedite the delivery of the final crowns for teeth requiring crown lengthening surgery: a pilot study

BACKGROUND

The healing period from crown lengthening procedures (CLPs) often delays the final crown delivery. This study aimed to explore the feasibility of a new approach expediting the delivery of the final crowns for teeth requiring CLPs.

METHODS

Teeth requiring CLPs and single-crown restorations between the canine and the second molar were included. After the initial tooth preparation, a CLP was performed. In the experimental group, the final tooth preparation and final impression were made during the CLP; the final crown was then delivered at the suture-removal appointment. In the control group, the final impression was made 8 weeks after the CLP. The level of gingival margin (GM), pocket depth (PD), and crestal bone levels (CBLs) were compared between the two groups before CLPs (T0), at delivery of the crowns (T1), and at 12 months in function (T2).

RESULTS

Twenty-one lithium-disilicate crowns were delivered to 20 subjects and followed up. The mean interval between the CLPs and the delivery of crowns was 2.5 weeks for the experimental group and 12 weeks for the control group. No significant differences were observed between the two groups in the level of GM, PD, and CBLs at each time point. No significant treatment difference in crestal bone loss was observed between the two groups at T2 (Experimental = -0.11 mm, Control = -0.03 mm; p = 0.67).

CONCLUSION

Making the final tooth preparation and the final impression at the CLP significantly reduced the time between the CLP and the delivery of the final crown and showed comparable clinical outcomes.

Deep Margin Elevation: Current Concepts and Clinical Considerations: A Review

Dietschi and Spreafico first proposed deep margin elevation (DME) in 1998 to address the multiple clinical problems associated with sub-gingival margins, where sub-gingival margins will be repositioned coronally using composite resin restorations. Given that dentistry is directing towards conservatism, its use is currently trending. Materials and Methods: a search was performed through PubMed, Scopus, and Google Scholar search engines to obtain relevant articles with no time restriction. Results: With biological width taken into consideration, well-defined and polished sub-gingival restorations are compatible with periodontal health. Marginal integrity in the DME technique seems to be affected by the type of adhesive, restoration, and incremental layering of the restoration. Regarding fracture resistance, DME has no significant effects. Conclusion: The DME technique seems to be a minimally invasive alternative to surgical crown lengthening (SCL) and orthodontic extrusion (OE) with respect to biological width. Well-controlled clinical trials are limited in this field; further long-term follow-up studies emphasizing the periodontal outcomes and prevention of complications are needed.

Diagnostic Mock-Up as a Surgical Reduction Guide for Crown Lengthening: Technique Description and Case Report

Background and Objectives: The report describes a technique using a diagnostic mock-up as a crown-lengthening surgical guide to improve the gingival architecture. Materials and Methods: The patient's primary concern was improving her smile due to her "gummy smile" and short clinical crowns. After clinical evaluation, surgical crown lengthening accompanied by maxillary central full-coverage single-unit prostheses and lateral incisor veneers was recommended. The diagnostic mock-up was placed in the patient's maxillary anterior region and used as a soft tissue reduction guide for the gingivectomy. Once the planned gingival architecture was achieved, a flap was reflected to proceed with ostectomy in order to obtain an appropriate alveolar bone crest level using the overlay. After six months, all-ceramic crowns and porcelain veneers were provided as permanent restorations. Results: A diagnostic mock-up fabricated with a putty guide directly from the diagnostic wax-up can be an adequate surgical guide for crown-lengthening procedures. The diagnostic wax-up was used to fabricate the diagnostic mock-up. These results suggested that it can be used as a crown-lengthening surgical guide to modify the gingival architecture. Several advantages of the overlay used in the aesthetic complex case include: (1) providing a preview of potential restorative outcomes, (2) allowing for the appropriate positioning of gingival margins and the desired alveolar bone crest level for the crown-lengthening procedure, and (3) serving as a provisional restoration after surgery. Conclusions: The use of a diagnostic mock-up, which was based on a diagnostic wax-up, as the surgical guide resulted in successful crown lengthening and provisional restorations. Thus, a diagnostic overlay can be a viable option as a surgical guide for crown lengthening.

Assessment of Negative Gingival Recession: A Critical Component of Periodontal Diagnosis

Accurate measurement of negative gingival recession (GR) is essential to accurately determine the clinical attachment loss, which leads to an accurate diagnosis and optimal therapy of periodontal disease. However, the accuracy of measuring the negative GR has been shown to be low and highly variable between examiners. The position of the gingiva margin in relation to the cemento-enamel junction (CEJ) varies among different stages of passive eruption. The amount of negative GR is about 2 mm on average at the mid-facial sites and ranges from 2 to 3.5 mm at interproximal sites in periodontally healthy patients. Some other clinical conditions may change the gingival dimension coronal to the CEJ, such as altered passive eruption and gingival enlargement. In addition to the traditional approach using a periodontal probe to assess the negative GR, nowadays dental ultrasound imaging may be able to assist in accurately measuring the amount of negative GR. This narrative review will discuss the existing evidence of the dimension of dentogingival tissue and the clinical assessment of negative GR using different clinical tools.

Crown Lengthening Techniques and Modifications to Treat Excessive Gingival Display

Dental aesthetics are a fundamental treatment goal in dentistry, in which even minute deviations from the ideal may necessitate corrective treatment or constitute a suboptimal clinical outcome. A well-defined protocol that adheres to sound biological and surgical principles is necessary to harmoniously integrate the dental and periodontal components. This article reviews clinical and aesthetic guidelines based on these principles for clinical crown lengthening.

Treatment for Chronic Periodontitis with Class II Furcation Involvement: A Case Report with Four-year Follow-up

This report describes a case of generalized chronic periodontitis requiring periodontal treatment including surgery. The patient was a 64-year-old man who visited the Tokyo Dental College Suidobashi Hospital with the chief complaint of pain in tooth #27. An initial examination revealed a probing depth (PD) of ≥4 mm at 38.2% of sites and bleeding on probing at 26.5% of sites. Radiographic examination revealed vertical bone resorption in # 27, 34, and 47, and horizontal resorption in other areas. Based on a clinical diagnosis of severe chronic periodontitis, initial periodontal therapy consisting of plaque control, scaling and root planing was performed. Both #27 and #47 were extracted due to bone resorption extending as far as the root apex. After initial periodontal therapy, sites with a PD of ≥4 mm were observed at 16.7% of sites. Furcation involvement was observed in #16, 17, 36, and 37. The need and options for periodontal surgery based on these findings were explained to the patient. Open flap debridement was implemented for #16, 17, 31, 34, 36, and 37 to reduce periodontal pockets. After reevaluation, the patient was placed on supportive periodontal therapy. The results of the periodontal examination at first visit revealed a periodontal pocket depth of 6 mm and 7 mm in #16 and 17, respectively, and class II furcation involvement in both. Periodontal therapy with open flap debridement resulted in an improvement in horizontal bone resorption where there was class II furcation involvement. This improvement has been adequately maintained over a 4-year period.

Relationship between smile type and periodontal phenotype: a clinical and tomographic cross-sectional study

OBJECTIVES

To evaluate the correlation between smile type (ST) and the periodontal phenotype (PP).

MATERIAL AND METHODS

Clinical and photographic examinations of 164 participants (48 men and 116 women, mean age 22.9 ± 4.6 years) were performed, including an evaluation of ST (high, average, and low), gingival phenotype (GP) by transparency of the periodontal probe (TRAN), keratinized tissue width (KTW), gingival architecture (GA), tooth shape (TS), and papilla height (PH). A subgroup of 70 participants underwent soft-tissue cone-beam tomographic examinations (ST-CBCT), in which GP, gingival thickness (GT), buccal bone thickness (BBT), and the distances from the gingival margin and cementoenamel junction to the buccal bone crest (GM-BBC and CEJ-BBC) were evaluated. The data were analyzed using one-way ANOVA, Student's t-test, and chi-square tests, with the level of significance set at 0.05.

RESULTS

High, average, and low STs were found in 31.7%, 56.7%, and 11.6% of the participants, respectively. Sex (p=0.001), GP evaluated using TRAN (p=0.021) and ST-CBCT scans (p=0.009), GA (p<0.001), and TS (p=0.001), were associated with STs. The prevalence of thin GP was: 63% in low, 50% in average, and 38% in high smile types. KTW (p=0.004), PH (p<0.001), GT at different landmarks (p<0.05), CEJ-BBC (p=0.017), and GM-BBC (p=0.001) were significantly different among STs. The highest GT and KTW were found in the high-smile group, average-smile presented the higher CEJ-BBC while GM-BBC and PH, were higher in low-smile group.

CONCLUSION

Periodontal phenotype components presented important difference over the smile types.

CLINICAL RELEVANCE

A detailed examination of smile types is an essential part of treatment planning, especially when the patient has high esthetic demands. Clinical and tomographic individual analysis of periodontal phenotypes over the smile types may be helpful for a case-by-case approach, and for the development of well-defined treatment protocols.

Agreement in measurements of ultrasonography-derived periodontal diagnostic parameters among multiple raters: A diagnostic accuracy study

OBJECTIVE

The aim of this study was to investigate the reproducibility of measurements of ultrasound-derived periodontal diagnostic parameters (PDPs) among raters.

STUDY DESIGN

Periodontists with various degrees of ultrasound experience were invited to measure 3 PDPs: soft tissue height (STH), soft tissue thickness (STT), and crestal bone thickness (CBT) on 37 human periodontal ultrasound scans acquired at the midfacial site of non-molar maxillary teeth. After an online training session and a 2-week calibration exercise, intraclass correlation coefficients (ICCs) were estimated with mixed linear regression models. The interrater mean absolute differences (MADs) were calculated among the raters and between the raters and a reference standard examiner.

RESULTS

Thirteen raters participated in the study. MADs among the 13 raters were 0.18 mm (STH), 0.16 mm (STT), and 0.12 mm (CBT). ICC values for STH, STT, and CBT were 0.83, 0.77, and 0.76, respectively. The MADs between the raters and the reference standard were 0.23 mm (STH), 0.19 mm (STT), and 0.14 mm (CBT). Survey results showed that ultrasound has diagnostic value and is generally easy to learn.

CONCLUSIONS

Within the limitations of this study, good agreement was observed among ultrasound learners with various degrees of experience when measuring ultrasound-derived PDPs.

Restorative difficulty evaluation system of endodontically treated teeth

OBJECTIVE

This article provides an updated overview of restorative procedures of endodontically treated teeth.

CLINICAL CONSIDERATIONS

The different techniques and procedures to restore an endodontic treated tooth were considered in the last decades. While they are generally performed using bonding procedures in combination with or without the placement of a post into the root to build up the abutment, there has been a lack of interest in restorative difficulties that can be faced. Failures are represented such as debonding of the post, fracture of the root, decementation, and/or fracture of the restoration, microleakage of the margins. Essentially, the presence of a sufficient failure is considered a key point of a long prognosis. Different clinical factors can directly influence the type of restoration and the longevity of the treatment. The restorative difficulty evaluation system (RDES) is proposed in this article. This new system is composed of eight different clinical factors that are divided into six levels of difficulties. The RDES is composed of 1. Endodontic complexity and outcome, 2. Vertical amount of coronal residual structure and dimension of the pulp chamber, 3. Horizontal amount of coronal residual structure, 4. Restoration marginal seal, 5. Local interdisciplinary conditions, 6. the complexity of the treatment planning, 7. Functional need, 8. Dental wear and esthetic need.

CONCLUSION

This article reviews the RDES and outlines critical steps and tips for clinical success.

CLINICAL SIGNIFICANCE

The RDES allows to any clinician to evaluate restorative difficulties when an endodontic treated tooth must be restored, combines clinical aspects that can involve from the single tooth to a full mouth rehabilitation.

The use of diode laser in esthetic crown lengthening: a randomized controlled clinical trial

This clinical trial assessed patient comfort, satisfaction, and the achievement and maintenance of ideal gingival margin levels using laser compared to conventional surgery in sculpting the soft tissues during esthetic crown lengthening. Eighteen patients with altered passive eruption were treated in a randomized split-mouth design by laser or scalpel crown-lengthening surgery. Patients were evaluated for intra- and postoperative pain and bleeding at 3 and 7 days. Clinical parameters including clinical crown length, probing depth, plaque index, bleeding on probing, and clinical attachment level were recorded at baseline, 3 and 6 months postoperatively. A gradual reduction in postoperative pain was recorded for both sides with no statistically significant difference at 3 (scalpel: 4.4 ± 1.33, laser: 4.8 ± 1.34; p = 0.088) and 7 days (scalpel: 1.8 ± 0.94, laser: 1.8 ± 1.10; p = 0.655). A statistically significant gain of coronal tooth structure was observed at 1, 3, and 6 months. Stability in the post-crown-lengthening level of the gingival margin was achieved one month following the procedure with no significant changes in the following months. All patients reflected acceptable results based on clinical evaluation and patient-reported outcomes. The diode laser can be used effectively as an alternative to the scalpel for the management of altered gingival contour. CLINICAL SIGNIFICANCE : This study demonstrated that a diode laser is an effective tool for the management of cases with altered passive eruption. In addition, it gives insight to practitioners regarding the timing of esthetic restorative procedures and emphasizes the preservation of the gingival complex dimensions.

Flapless Er,Cr:YSGG laser versus traditional flap in crown lengthening procedure

Background/purpose

Laser technology and minimally invasive therapy has gained attention in many dentistry fields. Er,Cr:YSGG laser is the latest laser type that can be applied on both soft tissue and hard tissue. This study presents periodontal outcome of Er,Cr:YSGG laser flapless crown lengthening procedure compared with traditional technique.

Materials and methods

Twenty-five participants were divided into two groups: 13 patients were treated with the traditional method of crown lengthening and 12 patients were treated using a flapless Er,Cr:YSGG laser. Their periodontal status were measured and compared at baseline, immediately, one month, and three months after surgery.

Results

The results showed a significant increase in clinical crown length immediately after surgery in both groups. After a three-month follow-up, the gingival margin of the laser group remained at stable height with 0.17 ± 0.31 mm increase after surgery, while the gingival margin of traditional group showed both recession and rebounding by -0.13 ± 0.63 mm (p > 0.05) average.

Conclusion

The flapless Er,Cr:YSGG laser crown lengthening with its minimally invasive approach without flap reflection may be an alternative treatment for providing an adequate height of tooth for restoration.

Virtual Planning and Rapid 3D Prototyping Surgical Guide for Anterior Crown Lengthening Surgery: A Clinical Case Report

Progress with additive 3D printing is revolutionizing biomaterial manufacturing, including clinical dentistry and prosthodontics. Among the several 3D additive printing technologies, stereolithography is very popular as it utilizes light-activated resin for precise resolution. A simplified digital technique was used to fabricate two designs of a surgical guide for crown lengthening. Two cases are presented that utilized digital DICOM files obtained with computed tomography (CT) imaging and processed using four CAD software (Blue Sky Plan, Exocad, Meshmixer and 3D Slicer). The final models were converted to standard tesselation (STL) files and the guides were 3D printed with an additive sterelithography (SLA) printer. The first case was fabricated with a bone model from CBCT data, and the second case was generated with intraoral and wax-up scans alone. Both methods appear to be equally effective compared to using a conventional method of guide frabication. However, proximal bone reduction was a concern with both designs. Digitally fabricated 3D printed surgical guide for crown lengthening has merit and a practical design is needed for future clinical validation. This article is protected by copyright. All rights reserved.

Periodontal and Periapical Outcomes of Surgical Extrusion: A Prospective Clinical Volumetric Study

INTRODUCTION

Outcome predictors for the restoration of endodontically treated teeth mainly include cavity wall integrity and the presence of a 1.5-2 mm ferrule. However, in some clinical situations, the aforementioned predictors cannot be achieved. Three different techniques have been proposed to obtain an adequate ferrule respecting the supracrestal tissue attachment: surgical crown lengthening, orthodontic forced eruption, and surgical extrusion. There are little published prospective data evaluating periodontal changes after surgical extrusion. Therefore, the aims of this study were to report the outcome of surgical extrusion in single-rooted teeth, to digitally evaluate soft tissue volumetric changes after surgical extrusion, and to observe patient satisfaction regarding the treatment after a minimum of 1 year.

METHODS

This prospective clinical study was performed between 2017 and 2020. Thirteen patients referred for surgical extrusion met the following inclusion criteria: nonsmokers; systemically healthy with at least 1 straight, single-rooted tooth with an insufficient ferrule; a favorable tooth crown-to-root ratio, and no periodontal pathology. Preoperative clinical variables included patient age, sex and phenotype, tooth number, tooth mobility, crown-to-root ratio, gingival index (GI), probing pocket depths at 6 sites, bleeding on probing (BOP), and mesial and distal interproximal papillae volume. Surgical extrusion was performed by a single operator who completed the root canal treatment/retreatment and restored the teeth with a crown. One year later, all patients were controlled, and the following variables were recorded: tooth mobility, crown-to-root ratio, GI, pocket depth, BOP, interproximal papillae aspect, soft tissue rebound, periapical healing, marginal bone loss, and patient-reported outcome measures of the treatment. All variables were analyzed using a descriptive method (mean, %). The Wilcoxon test was used to evaluate pre- and postoperative clinical parameters at a significance level of .05.

RESULTS

At a mean follow-up period of 18.8 months, no teeth were extracted. Compared with preoperative GI and BOP, a significant reduction was observed at 1 year after surgery. Likewise, no significant differences in probing depths were shown, and only 1 tooth presented a type 2 mobility. The mean soft tissue rebound was -0.46 ± 0.69 mm. Overall, no significant interproximal papillae height loss was observed.Apical lesions were completely healed after surgery. The tooth crown-to-root ratio was favorable in all cases before extrusion, whereas in 3 cases it was appropriate (1 = 1), and only 1 case presented >25% of marginal bone loss during the follow-up period. The reported success rate was 92.3%, and patients were generally satisfied with the outcome.

CONCLUSIONS

Surgical extrusion of single-rooted teeth was successful with minimal or no soft tissue loss, and patients were satisfied with the surgical procedure and the esthetic result.

Width and thickness of the gingiva in periodontally healthy individuals in a central Indian population: a cross-sectional study

OBJECTIVES

The present study was performed to determine the gingival dimensions (width and thickness) among young individuals in a central Indian population.

MATERIALS AND METHODS

Periodontal probing depth, width of the keratinized and attached gingiva, and gingival thickness were recorded on maxillary and mandibular teeth from central incisor to first molar unilaterally in 75 systemically healthy individuals (32 males and 43 females; 19-30 years of age). Comparisons were made gender-wise, arch-wise, tooth-wise, and site-wise using either the Student's t test or the ANOVA.

RESULTS

Keratinized and attached gingiva were wider in the maxilla than in the mandible both at proximal and at mid-buccal aspects (p < 0.001). At the tooth level also, gingiva was wider at the maxillary teeth than the corresponding mandibular teeth and at proximal aspects than at the mid-buccal aspect (p < 0.001). Regarding the thickness, gingiva was thicker among males, in the mandible, and at inter-proximal sites (p < 0.001). In either arch, maximum thickness was observed at the incisor region and least at the canine region.

CONCLUSIONS

Dimensions of the gingival tissues vary between different populations and between different areas of the dentition within the same subject. These variations need to be better understood because these aspects may have an important bearing on periodontal treatment planning as width and thickness of gingiva are important in terms of maintenance of periodontal health.

CLINICAL RELEVANCE

The dimensions of the clinically healthy gingiva are important in clinical practice as they can influence the progression of periodontal disease as well as impact the outcome of periodontal and restorative and orthodontic therapy.

Treatment Prognosis of Restored Teeth with Crown Lengthening vs. Deep Margin Elevation: A Systematic Review

Crown lengthening surgery and deep margin elevation are two distinct approaches used to manage decayed teeth. This systematic review examined the survival rate of badly decayed teeth when restored using the crown lengthening technique and compared it to the deep margin elevation technique. The search was conducted during July 2020 and then again updated at the end of July 2021, and no restriction concerning publication status and time was applied during the search. Cochrane Database, EBSCO, Scopus, and Medline databases were searched electronically for relevant literature. Google Scholar was used as a secondary source. Predefined inclusion and exclusion criteria were used to select the relevant articles. PRISMA guidelines were followed. The focused PICO question was: 'Does the crown lengthening technique (I) provide a better survival rate (O) than deep margin elevation technique (C) following the restoration of badly decayed teeth (P).' A total of six articles were included after performing screening based on the eligibility criteria. Four studies focused on crown lengthening while two focused on deep margin elevation technique. A majority of the studies showed a high risk of bias owing to methodological insufficiencies. Crown lengthening (CL) treated cases showed a change in the free gingival margin at six months post-surgery. A tissue rebound was seen that was correlated to the periodontal biotype. Teeth treated with the deep margin elevation (DME) technique showed high survivability. There is a lack of high-quality trials examining surgical comparisons between CL and DME with long-term follow-up. Patient- and dentist-reported outcomes have not been given adequate consideration in the literature. Based on the limited evidence, it can be concluded that for restorative purposes, crown lengthening surgery can be successful in long-term retention of restored teeth. However, the deep margin elevation technique has a better survival ratio. Future well-designed and executed research will have an effect on the evidence and level of certainty for the best approach to treating severely decayed teeth.

Mandibular premolar transplantation to replace missing maxillary anterior teeth: A multidisciplinary approach

One of the most challenging problems for orthodontists is that of multiple missing maxillary teeth in a growing patient. In many patients, a good treatment option is autotransplantation. This case report describes the multidisciplinary treatment of an 11-year-old girl with regional odontodysplasia affecting the maxillary right and left central incisors, and congenitally missing maxillary left lateral incisor and canine. Autotransplantation of the mandibular second premolars to the affected area was combined with orthodontic space closure, and the transplanted premolars were reshaped and restored with a resin composite to be in line with the left central and lateral incisors. After completion of the orthodontic treatment, gingivectomy was performed to obtain an even gingival contour and symmetrical gingival tissue. Space closure of the maxillary anterior teeth was achieved. Autotransplantation enabled the patient to retain her natural teeth rather than having a prosthesis or dental implant. The autotransplanted tooth allows for alveolar bone growth in synchrony with neighboring teeth and the formation of normal interdental papilla while adapting to functional stimuli and confers a high survival rate in the long term.

Single-Tooth Rehabilitation Combining Root Displacement and Crown Lengthening Two-Year Follow-Up: A Case Report

CLINICAL RELEVANCE

Combined techniques to expose circumferential tooth structure associated with subsequent restoration may represent a valid option in many situations. This case provides an example of the successful management of the anterior tooth rehabilitation combining root displacement and crown lengthening.

SUMMARY

Rehabilitation of an extensively compromised single anterior tooth represents an intriguing challenge for dentists, particularly when the rehabilitation involves esthetic, psychosocial, and functional requirements. The success in rehabilitating a patient with a conservative approach depends on a critical evaluation of the remaining structures, precise treatment plan, systematic treatment strategies, and patient compliance. In this case, the patient's chief complaint was the undesirable appearance of the maxillary right lateral, caused by the displacement of the post and crown. Clinical examination revealed a remaining tooth with coronal fracture, severe loss of tissue due to caries, and absence of ferrule effect. Radiographic examination revealed that the fracture margin was located subgingival. This case report describes a single-tooth rehabilitation involving a combination of root displacement via orthodontic extrusion and crown lengthening. The rehabilitation was followed by post-and-core restoration using a prefabricated glass fiber post associated with a disilicate lithium crown. The clinical decision making and combined effect of both treatment strategies are explained in this report. The treatment required three months, including recovery times after surgery and the placement of the provisional crown. The patient was esthetically and functionally satisfied with the restoration. Patient follow-up examination was performed 24 months after the treatment. This clinical report contributes to the clinical practice and exemplifies the possibility of rehabilitating the natural tooth using combined techniques, which may offer particular advantages regarding prognosis and invested efforts.

Is There an Association between the Gingival Phenotype and the Width of Keratinized Gingiva? A Systematic Review

The concept of gingival phenotype and width of keratinized gingiva influencing the diagnosis and treatment in the periodontal scenario is relatively new. Soft and hard tissue dimensions of oral tissues are considered essential parameters in daily clinical practice. Factors such as the biotype category and the width of the keratinized gingiva help dentists seek the perfect therapy plan for each patient to achieve long-term stability of periodontal health. Several methods have been proposed to categorize phenotypes and each phenotype is characterized by various clinical characteristics. This review aims to discuss the possible association between the gingival phenotype and the width of keratinized gingiva along with the results appeared. After a rigorous search in major electronic databases, the results of the included studies indicated that the width of keratinized gingiva seems to be associated with the periodontal phenotype, with thick biotypes being characterized by a more pronounced keratinized gingival width. However, the heterogeneity of the included studies did not allow to make a conclusion about a direct relationship.

Dual Digitally Guided Crown Lengthening in Esthetic Area Compromised by Disharmonic Implant Crown

INTRODUCTION

A disharmonious smile results from excessive gingival exposure or gingival margin misalignment is a frequent finding in patients. The most common cause is altered passive eruption; however, in the case presented here, the esthetics of the smile is compromised also due to an inadequate implant placement and crown fabrication.

CASE PRESENTATION

This case presented a combination of altered passive eruption and a buccally as well as deeply placed implant crown (#10) that led to disproportionate dimensions of an upper lateral incisor. Dual digitally guided crown lengthening surgical procedure for teeth #5 to #12 was performed aiming a better harmony of the smile. Treatment also included placement of tooth veneers and re-made of implant crown. A pleasant smile with appropriate colors and proportions was achieved. All esthetic and periodontal health parameters were maintained throughout the follow-up period (1 year).

CONCLUSION

The use of dual digitally guided crown lengthening help to accomplish precision and stability of esthetic outcome, as it guides for both, bone and soft tissue removal. Particularly, in challenging cases with high esthetic demand and complicated factors present, such as the case presented here, the digital approach provides tools to attain excellent treatment outcome.

Correlation analysis of periodontal tissue dimensions in the esthetic zone using a non-invasive digital method

Purpose

Direct intraoral scanning and superimposing methods have recently been applied to measure the dimensions of periodontal tissues. The aim of this study was to analyze various correlations between labial gingival thickness and underlying alveolar bone thickness, as well as clinical parameters among 3 tooth types (central incisors, lateral incisors, and canines) using a digital method.

Methods

In 20 periodontally healthy subjects, cone-beam computed tomography images and intraoral scanned files were obtained. Measurements of labial alveolar bone and gingival thickness at the central incisors, lateral incisors, and canines were performed at points 0–5 mm from the alveolar crest on the superimposed images. Clinical parameters including the crown width/crown length ratio, keratinized gingival width, gingival scallop, and transparency of the periodontal probe through the gingival sulcus were examined.

Results

Gingival thickness at the alveolar crest level was positively correlated with the thickness of the alveolar bone plate (P<0.05). The central incisors revealed a strong correlation between labial alveolar bone thickness at 1 and 2 mm, respectively, inferior to the alveolar crest and the thickness of the gingiva at the alveolar crest line (G0), whereas G0 and labial bone thickness at every level were positively correlated in the lateral incisors and canines. No significant correlations were found between clinical parameters and hard or soft tissue thickness.

Conclusions

Gingival thickness at the alveolar crest level revealed a positive correlation with labial alveolar bone thickness, although this correlation at identical depth levels was not significant. Gingival thickness, at or under the alveolar crest level, was not associated with the clinical parameters of the gingival features, such as the crown form, gingival scallop, or keratinized gingival width.

Periodontal plastic surgery for esthetic crown lengthening by using data merging and a CAD-CAM surgical guide

This article introduced a digital workflow by using data merging and a computer-aided design and computer-aided manufacturing (CAD-CAM) milled surgical guide for an esthetic crown lengthening procedure. The superimposition of intraoral scanning, digital photographs, cone beam computed tomography, and a CAD-CAM surgical guide should increase the predictability of esthetic crown lengthening surgery.

Restorative Alveolar Interface Management Combined With Tunnel Technique and Connective Tissue Graft: A Conservative Approach for Root Fracture Treatment

INTRODUCTION

The infringement of supracrestal tissue attachment by subgingival restorative margins, extensive caries, and root fractures, can compromise the periodontal health, resulting in inflammation and loss of periodontal supporting tissues. This report describes a case of a root fracture on the upper left central incisor that was successfully treated using a conservative approach, by applying the restorative alveolar interface (RAI) management combined with tunnel technique and a subepithelial connective tissue graft (SCTG).

CASE PRESENTATION

A 24-year-old male patient presented with a provisional single-unit fixed prosthesis on his upper left central incisor, in function for 4 years, with the chief complaint of prosthesis discoloration. After clinical and radiographic examination, a diagnosis of root fracture was established. Following the removal of the provisional prosthesis, a full-thickness flap was elevated creating a tunnel. The elimination of the fracture line/angle, root recontouring, and planning was then performed with the aid of a conical long diamond bur and periodontal curets. Additionally, an SCTG was placed buccally into the tunnel. The final zirconia layered with E-max crown was placed 6 months after surgery. At 12- and 24-month follow-up, the periodontal tissues presented healthy aspect, no bleeding on probing, and a 4-mm probing depth.

CONCLUSIONS

Surgical repositioning of the restorative margin can be an alternative and conservative treatment approach to compromised teeth with subgingival fracture line/angle. However, case selection should be carefully considered and restorability assessed as limitations might apply.

Clinical evaluation of impact of periodontal phenotype on the outcome of open flap debridement in patients with chronic periodontitis: A comparative interventional study

BACKGROUND

Several studies have implicated the role of periodontal phenotype (PP) in the outcome of various periodontal interventions. However investigations have not been performed to estimate such impact on the outcome of open flap debridement (OFD) for the management of chronic periodontitis.

METHODS

A total of 73 individuals with chronic periodontitis underwent scaling and root planing (SRP). Eight weeks following SRP, modified Widman flap (MWF) surgery was performed in 40 patients (20 of either PP) presenting with probing depth (PD) ≥4 mm and gingival index (GI) ≥1 at ≥4 sites distributed over ≥2 anterior teeth with radiographic evidence of horizontal bone loss. PD, clinical attachment level (CAL), gingival recession, plaque index, GI, and bleeding on probing (BOP) were recorded at baseline, 3 and 6 months. PP was assessed using transparency of periodontal probe through the gingival margin at midfacial level.

RESULTS

A total of 34 patients were re-evaluated after intervention. All periodontal parameters improved in both groups after periodontal surgery. PD & PP were found to have positive correlation with CAL gain in ≥7 mm probing sites. Attachment gain of >2 mm was observed in more percentage of sites in thick PP than in thin PP.

CONCLUSION

PP can be an important factor influencing CAL gain in OFD.

One- versus two-stage crown lengthening surgical procedure for aesthetic restorative purposes: A randomized controlled trial

AIM

This randomized controlled trial aimed to assess the efficacy of a two-stage crown lengthening intervention (SCL) in the aesthetic zone compared with a one-stage crown lengthening procedure (CCL).

MATERIALS AND METHODS

Thirty subjects were randomly assigned to either SCL (n = 15) or CCL (n = 15) groups. SCL consisted of full-thickness flaps followed by bone recontouring and gingivectomy 4 months postoperatively, if required. In CCL, osseous recontouring after submarginal incisions was performed, followed by flap repositioning. Records were obtained at baseline, 4 months (only in SCL), 6 months and 12 months. Primary outcome was the precision in achieving a pre-determined gingival margin position. Other outcomes considered were changes in the gingival margin position and keratinized tissue width (KTW) at 12 months, and patient-reported outcomes (PROMs).

RESULTS

Surgical precision was comparable between groups (0.2 ± 0.4 mm in the CCL group and -0.2 ± 0.5 mm in the SCL group). Four patients in the SCL group (27.7%) did not require a second-stage surgery. KTW was significantly higher in the SCL group (6.3 ± 1.4 mm versus 5.0 ± 1.4 mm, p = 0.017). SCL resulted in a lower impact on quality of life when compared to the CCL group.

CONCLUSIONS

Both approaches were highly accurate obtaining the desired crown length. SCL was associated with a lower reduction in KTW and more favourable oral health-related quality of life (OHIP-14).

Periodontal phenotype: A review of historical and current classifications evaluating different methods and characteristics

OBJECTIVE

To review the historical and current periodontal phenotype classifications evaluating methods and characteristics. Moreover, to identify and classify the methods based on periodontal phenotype components.

OVERVIEW

Several gingival morphology studies have been frequently associated with different terms used causing confusion among the readers. In 2017, the World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions recommended to adopt the term "periodontal phenotype". This term comprises two terms, gingival phenotype (gingival thickness and keratinized tissue width) and bone morphotype (buccal bone plate thickness). Furthermore, gingival morphology has been categorized on "thin-scalloped", "thick-scalloped" and "thick-flat" considering the periodontal biotype. However, by definition, the term phenotype is preferred over biotype. Periodontal phenotype can be evaluated through clinical or radiographic assessments and may be divided into invasive/non-invasive (for gingival thickness), static/functional (for keratinized tissue width), and bi/tridimensional (for buccal bone plate thickness) methods.

CONCLUSIONS

"Thin-scalloped," "thick-scalloped," and "thick-flat" periodontal biotypes were identified. These three periodontal biotypes have been considered in the World Workshop but the term periodontal phenotype is recommended. Periodontal phenotype is the combination of the gingival phenotype and the bone morphotype. There are specific methods for periodontal phenotype evaluation.

CLINICAL SIGNIFICANCE

The term periodontal phenotype is currently recommended for future investigations about gingival phenotype and bone morphotype. "Thin-scalloped," "thick-scalloped," and "thick-flat" periodontal phenotypes can be evaluated through specific methods for gingival thickness, keratinized tissue width, and buccal bone plate thickness evaluation.

[Relationships among the periodontal biotype characteristics in the maxillary anterior]

OBJECTIVE

To explore the correlation among gingival thickness (GT), underlying alveolar bone thickness (BT), and other periodontal biotype characteristics in the maxillary anterior.

METHODS

A total of 40 young volunteers with healthy periodontal were involved in this research. The periodontal probe was previously used to divide the gingiva from thick to thin. Two records were measured by cone beam CT (CBCT) GT, which was measured at the cement-enamel junction level; and BT, which was measured at 3 locations: 1, 3, 5 mm below the alveolar crest. Oral and gypsum measurements were used to analyze the associations of the crown width/crown length ratio (CW/CL), the keratinized mucosa width (KM), and the free gingival margin curvature.

RESULTS

Significant difference in the GT was observed between the thick and thin biotypes, which were divided by periodontal probe (P<0.01). Difference was observed in each periodontal biotype characteristic between the thick (GT≥1 mm) and thin biotypes (GT<1 mm) (P<0.05). BT was positively associated with GT (r=0.293, P=0.001), CW/CL (r=0.273, P=0.003), KM (r=0.291, P=0.001), and free gingival margin curvature (r=0.290, P=0.001).

CONCLUSIONS

The transparency of the probing in the sulcus could analyze the GT qualitatively. The thick and thin biotypes have different periodontal biotype characteristics. Compared with individuals with thick biotype, those with thin biotype are susceptible to risk dental aesthetic.

Biologically oriented preparation technique for surgically extruded teeth: A clinical report

Surgical extrusion allows a ferrule to be obtained without the use of orthodontic extrusion or the need to remove hard and soft tissues. However, after the healing period, the soft tissue of the extruded tooth might become thinner, creating an unesthetic gingival margin. Unlike other preparation techniques, the biologically oriented preparation technique provides increased long-term gingival thickness. This article describes the treatment of 3 patients with teeth with no ferrule that were surgically extruded and restored with the biologically oriented preparation technique .

Correlation between gingival phenotype in the aesthetic zone and craniofacial profile-a CBCT-based study

OBJECTIVES

To investigate the correlation between gingival phenotype and craniofacial profile and to evaluate the morphology of periodontal supporting tissues in the maxillary and mandibular anterior zones.

MATERIALS AND METHODS

A total of 66 patients with 264 central incisors in good periodontal health were included in this cross-sectional study. CBCT images were used to assess gingiva and alveolar bone thickness of the maxillary and mandibular incisors at four vertical levels. Cephalometric analysis was used to assess the sagittal profile of the craniofacial structures. Gingival thickness was compared in patients with different craniofacial profiles based on ANB value. Linear regression coefficients adjusted by age and gender were used to evaluate the correlation between gingival thickness and the cephalometric parameters.

RESULTS

Individuals with a smaller ANB value (ANB< 2) presented with thinner supporting tissue and a keratinized gingiva width in the anterior zone. Labial gingival thickness on the mandibular incisors at the cementoenamel junction (G1) and at the alveolar bone crest (G2) was positively related to cephalometric measures, indicating a maxillae-mandibular sagittal relationship (ANB value, Wits appraisal, A-NPog value).

CONCLUSIONS

A moderate correlation was found between mandibular gingival thickness and the sagittal craniofacial profile. Patients with a concave craniofacial profile had a smaller keratinized gingiva width and gingival thickness in the aesthetic zone.

CLINICAL RELEVANCE

Knowledge of these features on supporting tissue and their correlations with craniofacial morphology will help clinicians to develop a reasonable treatment plan and make decisions to achieve the best aesthetic outcome.

Guided Periodontal Surgery: Association of Digital Workflow and Piezosurgery for the Correction of a Gummy Smile

Digital flow has become a part of currently practiced dentistry. Virtual planning ensures predictable aesthetic and functional rehabilitation, painless postoperative recovery, and better communication with patients, thus meeting their expectations. The purpose of this case report is to demonstrate the digital planning for the correction of a gummy smile with a personalized preparation using a piezoelectric surgical guide (PerioGuide) for gingival contouring and flapless osteotomy. The guide was designed using Nemo Studio software, based on the patient's facial aesthetic analysis, through photos, videos, and facial scanning. These images were aligned with the scan and placed over the cone beam computed gingival tomography for prediction of results, based not only on the distance from the cementoenamel junction to the bone crest but also on the best gingival margin contour according to virtual aesthetic planning. Digital planning, combined with the use of a piezoelectric device, allows for a flapless guided surgical technique for gingival contouring and osteotomy. As a result, the surgical procedure is safer, faster, and more predictable with better postoperative outcomes.

Pocket elimination after osseous resective surgery: A systematic review and meta-analysis

AIM

To systemically review the available evidence on the clinical performance of osseous resective surgery (ORS) in the treatment of residual periodontal defects in terms of pocket elimination and biological costs in patients with chronic periodontitis.

MATERIALS AND METHODS

Three databases (PubMed, EMBASE and Cochrane) were searched up to January 2019. Clinical trials with a follow-up duration of at least 12 months after ORS with or without fibre retention technique were included. Quantitative synthesis was conducted with random-effect meta-analysis.

RESULTS

Overall, 1,765 studies were retrieved, of which 53 full-text articles were screened by two reviewers. Finally, a total of three RCTs were included in the meta-analysis. Random-effect meta-analysis showed a weighted mean percentage of pocket elimination (final PD ≤ 4 mm) at 12 months of 98.3% (95% CI: 96.8; 99.7) with I² of 26%. The weighted mean amount of resected bone was 0.87 mm (95% CI: 0.49; 1.25), and the weighted mean increase in gingival recession was 2.13 mm (95% CI: 1.49; 2.78) at 12 months.

CONCLUSIONS

ORS represents an effective surgical approach for the elimination of residual periodontal pockets in the short to medium term. Additional randomized controlled clinical trials with data on pocket elimination are warranted.

Stability of the gingival margin after an aesthetic crown lengthening procedure in the anterior region by means of a replaced flap and buccal osseous surgery: a prospective study

OBJECTIVES

The main objective of this study was to assess changes in the position of the gingival margin (GM) after performing an aesthetic crown lengthening (ACLP) by means of submarginal incisions, buccal osseous surgery, and a replaced flap after a healing period of 6 months.

METHODS

Twenty-one patients who needed a surgical crown lengthening in the maxillary anterior teeth were included. An individual stent was fabricated to record changes in the position of the GM. Clinical measurements were recorded pre-surgically; immediately post-surgically (baseline); and at 42, 90, and 180 days.

RESULTS

After the ACLP, the GM displacement did not change significantly after 42, 90, and 180 days (4.32 ± 1.17 mm, 4.29 ± 1.14 mm, and 4.26 ± 1.11 mm, respectively). Tissue rebound seems to be related to the distance from the GM to the alveolar bone (AB) at the time of suturing (GM-AB(X)). When GM-AB(X) was ≤ 2 mm, 3 mm, and ≥ 4 mm, the GM rebound at 6 months was 0.94 ± 0.53 mm, 0.10 ± 0.28 mm, and - 0.26 ± 0.40 mm, respectively. These differences were statistically significant (P < 0.001).

CONCLUSIONS

An ACLP releasing the flap up to the mucogingival junction, with a ≥ 3-mm distance from the bone crest to the gingival margin can lead to a stable GM position at 42, 90, and 180 days.

CLINICAL RELEVANCE

This article focuses on variables affecting the stability of the GM, which is a critical factor that may compromise the biological and aesthetic long-term outcomes.

Is measurement of the gingival biotype reliable? Agreement among different assessment methods

BACKGROUND

To determine agreement among the most commonly used methods for assessing the gingival biotype.

MATERIAL AND METHODS

An electronic survey was sent to a sample of dentists practicing in Spain. The questionnaire was based on the evaluation of 5 cases involving different gingival biotype assessment methods. Dentists were required to classify the cases as having a "thin", "thick" or "not able to classify" biotype. Each case was assessed using a frontal intraoral photo of the anterior teeth; an enlarged photo of the buccal aspect of the tooth with a periodontal probe inserted inside the sulcus; and the real thickness measured in mm with a calibrated needle. Agreement among the classifications was assessed using Cohen's kappa coefficient.

RESULTS

A total of 104 surveys were analyzed. The most commonly used assessment method was visual evaluation of the morphology of the gingiva and the teeth (62.5%). Concordance among the three different methods was weak (kappa = 0.278). Agreement among the classification methods was greater in extreme cases (thinner and thicker gingival thickness).

CONCLUSIONS

The most commonly used methods for assessing gingival biotype are not reliable. The three tested methods show poor to weak agreement, which leads to non-reliable estimation of the gingival biotype.

New Tricks in the Preparation Design for Prosthetic Ceramic Laminate Veeners

Background: The prosthetic preparation of the teeth for ceramic laminate veneers has to follow the minimally invasive concept brought by the modern Conservative Dentistry and Prosthodontics. However, during the cementation phase under the rubber dam, the loss of the esthetics landmarks could lead to errors in the future positioning of the laminate veneers. Methods: In this article the authors show an accurate operative prosthetic protocol using different fine intraoperative maneuvers and tricks for the realization of ceramic laminates in order to solve the problems of the cementation phase. Results: The treatment of the anterior sector of the upper maxilla with porcelain laminate veneers was realized in a 30 years old woman with aesthetic issues. Conclusion: Different fine intraoperative maneuvers and tricks during teeth preparation, master impression and rubber dam positioning could reduce errors occurring in the cementation phase and increase the predictability of the results.

Clinical and histological reaction of periodontal tissues to subgingival resin composite restorations

OBJECTIVES

To compare the clinical and histological response of supracrestal periodontal tissues to subgingival composite restorations versus natural root surfaces MATERIAL AND METHODS: In 29 subjects with a single tooth requiring subgingival restorations, a deep margin elevation (DME) procedure with composite resin was applied. Full-mouth plaque score (FMPS), full-mouth bleeding score (FMBS), and focal probing depth (PD) were measured at baseline, before DME, and after 3 months. The distance between the coronal marked (CM) point to the apical margin of the composite reconstruction (AMR), at baseline, and to the tip of the periodontal probe inserted to reach the bottom of the sulcus (APP), 3 months later, was measured. An all-around secondary flap, harvested to ensure the subsequent single-crown prosthetic rehabilitation was histologically processed. The histological inflammation degree was evaluated in areas of gingival tissues adjacent to the composite (group B) and adjacent to the natural surface of each single tooth (group A).

RESULTS

Significant FMPS, FMBS, and PD decreases were observed (p < 0.05). CM-AMR and CM-APP were significantly different (p < 0.05), suggesting an attachment gain after 3-months. The inflammation level of gingival tissue was similar in groups A and B (p > 0.05).

CONCLUSIONS

For the first time, this topic was clinically and histologically studied in humans. Subgingival restorations resulted compatible with gingival health, with levels similar to that of untreated root surfaces.

CLINICAL RELEVANCE

Deep margin elevation procedure produces favorable clinical and histological outcomes allowing a routine utilization in reconstructive dentistry.

Update on Perio-Prosthodontics

Knowledge of the periodontal-restorative interface is critical in the fabrication of restorations that are functional and esthetic. Understanding biological principles allows the clinician to predict how the periodontium will respond to restorative therapy. Factors that influence the response to therapy in the periodontal-restorative interface are periodontal biotype, gingival architecture, alveolar crest position, gingival margin position, and gingival zenith.