Evaluation of the adjunctive use of Er:YAG laser or erythritol powder air-polishing in the treatment of peri-implant mucositis: A randomized clinical trial.

AIM: To assess the efficacy of Er:YAG laser (ERL) and erythritol powder air-polishing (AP) in addition to the submarginal instrumentation in the non-surgical treatment of peri-implant mucositis (PM). MATERIALS AND METHODS: Patients with at least one implant diagnosed with PM were included in the present 6-month randomized clinical trial (RCT). Implants were randomly assigned to one of the three treatment groups after submarginal instrumentation: AP (test 1 group), ERL (test 2 group) or no adjunctive methods (control group). The primary and secondary outcomes were, respectively, bleeding on probing (BoP) reduction and, complete disease resolution (total absence of BoP) and probing pocket depth (PPD) changes. The patient and the implant were considered the statistical unit. A multivariate logistic regression analysis was performed. RESULTS: A total of 75 patients were enrolled in the study. At each time point, significant BoP and PPD reductions were observed within each group. Intergroup analysis did not show statistically significant differences. Complete disease resolution ranged between 29% and 31%. The logistic regression showed that supramucosal restoration margin, PPD < 4 mm and vestibular keratinized mucosa (KM) significantly influenced the probability to obtain treatment success. CONCLUSION: The adjunctive use of AP and ERL in PM non-surgical therapy does not seem to provide any significant or clinically relevant benefit in terms of BoP and PPD reductions and complete disease resolution, over the use of submarginal instrumentation alone. Baseline PPD < 4 mm, presence of buccal KM and supramucosal restoration margin may play a role in the complete resolution of PM.

Soft and hard tissue changes after immediate implant placement with or without a sub-epithelial connective tissue graft: Results from a 6-month 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 tissue healing, without a bone replacement graft in the gap between the implant and the socket walls. MATERIALS 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 and optically scans were performed before tooth extraction and at 6-month 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 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 of the 30 enrolled patients attended the 6-month follow-up visit. The four patients of the control group that were lost to follow-up were analysed under the intention-to-treat principle. No statistically significant differences between the groups were observed for the vertical buccal bone resorption (p = .90), as well as for the horizontal buccal bone resorption at all measured levels. Significant differences were found between the test and control groups in the horizontal dimensional changes of osseous ridge at the most coronal aspect (p = .0003 and p = .02). Changes in tissue contour were 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 in 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 a statistically significant difference. CONCLUSIONS: The findings of the present study indicate that the adjunct of a CTG at the time of IIP, without bone grafting, does not influence vertical bone resorption. Within the limits of this study, it can be suggested that the adjunct of a CTG at the time of IIP, 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.

The effect of immediate implant placement on alveolar ridge preservation compared to spontaneous healing after tooth extraction: Soft tissue findings from a randomized controlled clinical trial.

AIM: To compare soft tissue dimensional changes and relative differences in soft and hard tissue volumes 4 months after single-tooth extraction and three different treatment modalities: spontaneous healing (SH) and alveolar ridge preservation by means of a deproteinized bovine bone mineral and a collagen matrix, with (IMPL/DBBM/CM) or without (DBBM/CM) immediate implant placement. MATERIALS AND METHODS: STL files from study casts obtained at baseline and after 4 months were matched to calculate buccal soft tissue linear and volumetric changes. DICOM files from CBCTs were superimposed to STL files allowing the evaluation of soft tissue thickness at baseline and 4 months. RESULTS: Mean horizontal reduction accounted for 1.46 ± 0.20 (SH), 0.85 ± 0.38 (DBBM-CM) and 0.84 ± 0.30 IMPL/DBBM-CM, with no statistical differences. Soft tissue thickness had a significant mean increase of 0.95 for SH group, compared to a non-significant mean decrease for DBBM-CM (0.20) and IMPL/DBBM-CM groups (0.07). CONCLUSION: A preservation technique with DBBM-CM, with or without immediate implant placement, did not reduce the horizontal linear and volumetric changes at the buccal soft tissue profile significantly at 4 months after tooth extraction when compared to spontaneous healing. This is due to a significant increase in soft tissue thickness in spontaneously healing sites.

Prevalence and risk indicators of gingival recessions in an Italian school of dentistry and dental hygiene: a cross-sectional study.

OBJECTIVES: The aim of this cross-sectional study is to (i) determine the prevalence, extent, severity, and distribution of gingival recessions and patient perception in a young population and (ii) to identify potential risk indicators. MATERIAL AND METHODS: Two hundred fifty-one students with a mean age of 22.9 ± 4.7, attending the School of Dentistry and Dental Hygiene of Vita-Salute San Raffaele University (Milan, Italy) were included. The subjects had undergone a clinical evaluation, by two calibrated examiner, and a questionnaire. Demographic and clinical data were collected to evaluate association of these factors with gingival recessions. RESULTS: The prevalence of gingival recessions at patient and tooth level was 39% and 5.2%, respectively. The only factor associated with the presence of GR was age. On the other hand, age and smoking were associated with the extent, whereas BOP, NCCLs and KT were associated with the severity. Out of 98 subjects presenting at least one GR, 63 (64%) were conscious of the presence of the GR. NCCLs were also strongly associated with the perception of the recession by the patient. CONCLUSIONS: There is a low prevalence of buccal gingival recessions in this sample of Italian students. More than 50% of the sample was aware of the problem. Almost all patients presenting symptomatology or aesthetic concern requested appropriate therapy. CLINICAL RELEVANCE: The findings highlight the low relevance of gingival recessions in daily practice and the importance of controlling potential risk indicators in young populations.

Clinical performance of minimally invasive periodontal surgery in the treatment of infrabony defects: Systematic review and meta-analysis.

AIM: To assess the effectiveness, in terms of clinical performance and patient perception, of minimally invasive periodontal surgeries (MIPSs), and to compare MIPSs to traditional surgery in the treatment of periodontal infrabony defects. MATERIALS AND METHODS: An electronic search and a manual search were carried out to identify studies investigating clinical (CAL, PPD, REC), radiographic (bone fill) and patient's centred (VAS) outcomes at least 6 months after MIPSs. A linear mixed-effect model was used for meta-analysis. Subgroup analyses were performed according to the study quality (RCT or case series). A meta-analysis assessing differences in clinical parameters between MIPSs and traditional flaps was also performed. RESULTS: Meta-analysis from the 18 included studies revealed a PPD reduction of 4.24 mm (95% CI = 3.79-4.69 mm), a CAL gain of 3.89 mm (95% CI = 3.42-4.35 mm), a REC increase of 0.44 mm (95% CI = 0.11-0.77 mm), a radiographic bone fill gain of 58.25% (95% CI = 42.30%-74.21%) and a VAS value of 1.16 (95% CI = 0.78-1.54). Based on 2 RCTs, MIPSs are more effective than traditional surgery for PPD reduction (0.93 mm, 95% CI = 1.71-0.15) and CAL gain (1 mm, 95% CI = 1.75-.24). CONCLUSION: Minimally invasive periodontal surgeries may be considered for the treatment of periodontal infrabony defects. However, the real effect cannot be systematically evaluated due to the paucity of studies comparing MIPSs to traditional flap for periodontal reconstructive surgery.

Prevalence and risk indicators of peri-implantitis in a sample of university-based dental patients in Italy: A cross-sectional study.

AIM: Reports regarding prevalence of peri-implant diseases show widely varying prevalence rates, which can be explained partially by variable diagnostic criteria adopted. Furthermore, several different factors have been associated with peri-implant diseases. Hence, the aim of this cross-sectional study is to (a) determine the prevalence, extent and severity of peri-implant diseases in patients enrolled in a university dental clinic and (b) to evaluate the association between peri-implantitis and patient/implant-related factors. MATERIAL AND METHODS: A total of 237 subjects from the Dental Department of Vita-Salute San Raffaele University (Milan, Italy) with 831 implants with more than 1 year of follow-up after loading were clinically evaluated. Implants showing bleeding on probing (BOP), with or without suppuration, and/or probing pocket depth (PPD) ≥ 4 mm, were radiographically analysed. Demographic and clinical data were collected to evaluate by multilevel regression analysis association with peri-implantitis. RESULTS: The prevalence of peri-implant mucositis and peri-implantitis was 38.8% and 35%, respectively. Patients with a FMBS > 25%, having ≥4 implants as well as implants with plaque, PPD ≥ 4 mm or less than 1 mm of keratinized mucosa presented higher odds ratios for peri-implantitis. CONCLUSIONS: Peri-implant diseases are frequent conditions affecting >70% of the patients. Several patient/implant-related factors may influence the risk for peri-implantitis.

The effect of immediate implant placement on alveolar ridge preservation compared to spontaneous healing after tooth extraction: Radiographic results of a randomized controlled clinical trial.

AIM: To radiographically evaluate the effect of immediate implant placement plus alveolar ridge preservation (ARP) with a deproteneized bovine bone mineral and a collagen matrix (IMPL/DBBM/CM) as compared to ARP (DBBM/CM) or spontaneous healing (SH) on vertical and horizontal bone dimensional changes after 4 months of healing. MATERIALS AND METHODS: Thirty patients requiring extraction of one single-rooted tooth or premolar were randomly assigned to IMPL/DBBM/CM, ARP DBBM/CM or SH. Cone-beam computed tomography (CBCT) scans, performed before tooth extraction and after 4 months, were superimposed in order to assess changes in ridge height at the buccal and lingual aspect and in ridge width at 1 mm, 3 mm and 5 mm apical to the bone crest. Kruskal-Wallis test was applied for comparison of differences between groups. RESULTS: No statistically significant differences between the groups were observed for the vertical bone resorption of the buccal and the lingual side, while significant differences were found between SH group (-3.37 ± 1.55 mm; -43.2 ± 25.1%) and both DBBM/CM (-1.56 ± 0.76 mm; -19.2 ± 9.1%) and IMPL/DBBM/CM (-1.29 ± 0.38 mm; -14.9 ± 4.9%) groups in the horizontal dimension at the most coronal aspect. CONCLUSION: Ridge preservation techniques using DBBM and CM reduce the horizontal bone morphological changes that occur, mostly in the coronal portion of the buccal bone plate following tooth extraction, when compared to spontaneous healing. This is true regardless of whether immediate implant placement is performed or not.

Biologically guided flap stability: the role of flap thickness including periosteum retention on the performance of the coronally advanced flap-A double-blind randomized clinical trial.

AIM: To evaluate the possible benefit on wound healing and flap stability of periosteum inclusion, comparing a "split-full-split" thickness flap elevation versus a "split" thickness approach performed during CAF for the treatment of isolated-type gingival recessions in the upper jaw. MATERIAL AND METHODS: Forty patients were randomized, 20 were treated with "split-full-split" (test group) and 20 with a "split" approach (control group). Analysed parameters at 1 year were CRC, percentage of recession coverage (RC), keratinized tissue (KT) gain and patient-related outcome measurements. RESULTS: After 12 months, CRC was 80% in the test group and 35% in the control group. Percentages of RC and KT gain were higher in the test group, and a significant association between CRC and the thickness of the flap after elevation was found. Patient-related outcomes measurements were better for the test group. CONCLUSIONS: Flap thickness preservation and the presence of the periosteum in part of the flap may play a fundamental role in obtaining CRC.

Treatment of class III multiple gingival recessions: Prognostic factors for achieving a complete root coverage.

BACKGROUND: This report is intended to present a supplemental analysis of data from a prior report (Aroca et al., ) to investigate factors associated with a complete root coverage at 1 year. The purpose of the prior report was to investigate at 1 year the adjunction effect of EMD for the treatment of Miller's class III recession defects using a coronally advanced modified tunnel/CTG technique with (test group) or without (control group). The purpose of this report was to investigate additional factors associated with root coverage in the same data set. MATERIALS AND METHODS: On the 138 observations collected from 20 patients, a regression model was used to highlight the relationship between the percentages of root coverage (RC) and three following covariates: the distance from the tip of the papilla and the contact point (DCP) at baseline, the group membership (control vs. test) and tooth position in the mouth (maxillary vs. mandibular). RESULTS: The statistical analysis showed that there was a significant effect of the DCP at baseline (p = 0.01) and of the tooth type (p < .001) on the percentage of RC at 1 year, whereas no significant difference between the two techniques (group membership effect) was shown (p = 0.69). CONCLUSION: The probability to obtain a complete root coverage decreases when the DCP at baseline increases. Moreover, maxillary teeth are more likely to give better RC than mandibular teeth. However, in this analysis similar to the last, there was no group effect.

Periodontal manifestations of systemic diseases and developmental and acquired conditions: Consensus report of workgroup 3 of the 2017 World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions.

BACKGROUND: A variety of systemic diseases and conditions can affect the course of periodontitis or have a negative impact on the periodontal attachment apparatus. Gingival recessions are highly prevalent and often associated with hypersensitivity, the development of caries and non-carious cervical lesions on the exposed root surface and impaired esthetics. Occlusal forces can result in injury of teeth and periodontal attachment apparatus. Several developmental or acquired conditions associated with teeth or prostheses may predispose to diseases of the periodontium. The aim of this working group was to review and update the 1999 classification with regard to these diseases and conditions, and to develop case definitions and diagnostic considerations. METHODS: Discussions were informed by four reviews on 1) periodontal manifestions of systemic diseases and conditions; 2) mucogingival conditions around natural teeth; 3) traumatic occlusal forces and occlusal trauma; and 4) dental prostheses and tooth related factors. This consensus report is based on the results of these reviews and on expert opinion of the participants. RESULTS: Key findings included the following: 1) there are mainly rare systemic conditions (such as Papillon-Lefevre Syndrome, leucocyte adhesion deficiency, and others) with a major effect on the course of periodontitis and more common conditions (such as diabetes mellitus) with variable effects, as well as conditions affecting the periodontal apparatus independently of dental plaque biofilm-induced inflammation (such as neoplastic diseases); 2) diabetes-associated periodontitis should not be regarded as a distinct diagnosis, but diabetes should be recognized as an important modifying factor and included in a clinical diagnosis of periodontitis as a descriptor; 3) likewise, tobacco smoking - now considered a dependence to nicotine and a chronic relapsing medical disorder with major adverse effects on the periodontal supporting tissues - is an important modifier to be included in a clinical diagnosis of periodontitis as a descriptor; 4) the importance of the gingival phenotype, encompassing gingival thickness and width in the context of mucogingival conditions, is recognized and a novel classification for gingival recessions is introduced; 5) there is no evidence that traumatic occlusal forces lead to periodontal attachment loss, non-carious cervical lesions, or gingival recessions; 6) traumatic occlusal forces lead to adaptive mobility in teeth with normal support, whereas they lead to progressive mobility in teeth with reduced support, usually requiring splinting; 7) the term biologic width is replaced by supracrestal tissue attachment consisting of junctional epithelium and supracrestal connective tissue; 8) infringement of restorative margins within the supracrestal connective tissue attachment is associated with inflammation and/or loss of periodontal supporting tissue. However, it is not evident whether the negative effects on the periodontium are caused by dental plaque biofilm, trauma, toxicity of dental materials or a combination of these factors; 9) tooth anatomical factors are related to dental plaque biofilm-induced gingival inflammation and loss of periodontal supporting tissues. CONCLUSION: An updated classification of the periodontal manifestations and conditions affecting the course of periodontitis and the periodontal attachment apparatus, as well as of developmental and acquired conditions, is introduced. Case definitions and diagnostic considerations are also presented.

Guided bone regeneration of non-contained mandibular buccal bone defects using deproteinized bovine bone mineral and a collagen membrane: an experimental in vivo investigation.

AIM: The aim of this pre-clinical in vivo study was to analyse different stages of wound healing after guided bone regeneration in non-contained mandibular buccal bone defects. MATERIALS AND METHODS: Eighteen female beagle dogs, between 1.5 and 2 years old, were used. Buccal bone defects were created in the mandible following extraction of the mesial roots of M1, P4, the distal root of P3 and booth roots of P2. Augmentation procedures of the healed defects were performed 3 months later using a bone replacement graft (T1), an absorbable collagen membrane (T2) or a combination of both procedures (T3). Using a randomized block study design, four stages of healing in two groups of dogs were examined (4 days, 2, 6 weeks and 3 months). The animals were euthanized, and biopsies obtained at the end of each of the study periods were prepared for histological examination. RESULTS: The different reconstructive procedures resulted in regenerated tissue compartments of varying size that contained newly formed bone, non-mineralized tissue and bone augmentation biomaterial when a bone replacement graft was used. While the proportions of mineralized tissue increased and non-mineralized tissue decreased over time in the three groups, the changes in proportions of the DBBM material were small. Initial defect depth, healing time and treatment group significantly influenced the percentage of mineralized tissue obtained. The multivariate multilevel analysis showed that significantly larger area proportions of mineralized tissue were obtained when the T2 sites were compared with T1 and T3 sites, what highlights the importance of the barrier membrane effect for attaining new bone formation. Only in the larger size defects (M1) total ROI at T3 and T1 sites was significantly larger than at T2, what highlights the importance of using a bone replacement graft as a space maintenance scaffold. CONCLUSION: It is suggested that healing following augmentation of non-contained buccal bone defects was characterized by a gradual shift in the relative proportions of non-mineralized and mineralized tissue components.

Lateral approach for sinus floor elevation: large versus small bone window - a split-mouth randomized clinical trial.

OBJECTIVES: To test whether a reduction of bone window dimension, in a split-mouth randomized study design, focused on lateral sinus floor elevations, can achieve better results than a wider window in terms of augmented bone height and a reduction of patient discomfort and surgical complications. MATERIALS AND METHODS: Of the sixteen subjects enrolled in the study, each underwent a bilateral sinus lift procedure based on two different access flaps to maxillary sinus. Test side: small access window (6 × 6 mm) + bone filling using a special device. Control side: large access window (10 × 8 mm) + manual bone filling. Alveolar bone height and width were measured at pre-op and 6-month post-op CT scans; repeatable measurements were obtained using radiographic stents. Surgical intervention duration was also recorded. Patients' evaluation of surgical discomfort was assessed using a VAS diagram at 7-day, 14-day and 30-day follow-up. RESULTS: A significant bone augmentation in height and width of alveolar crest was obtained in both test (8.71 ± 1.11 mm, 4.70 ± 0.58 mm) and control (8.5 ± 2.02 mm, 4.68 ± 0.70 mm) sides, although no significant differences were found between the two groups. Neither any significant differences emerge in data concerning the duration of the intervention (Test 42.62 ± 6.67 min, Control 41.68 ± 8.34 min). Patients' opinion relating to surgical discomfort showed a preference for test procedure at 7-day, 14-day and 30-day follow-up. CONCLUSIONS: A reduction of window dimensions did not affect the safety of the surgical procedure. The two testing techniques showed no statistically significant differences in surgical intervention duration. Patients' opinion at 7-day and 14-day post-op showed a preference for test procedure.

Patient-reported outcomes and aesthetic evaluation of root coverage procedures: a 12-month follow-up of a randomized controlled clinical trial.

AIM: To assess patient-reported outcome measures (PROMs), aesthetics and stability of root coverage procedures from a previous 6-month RCT after 1 year. MATERIAL & METHODS: Forty-five patients (90 recessions) had received a coronally advanced flap (CAF = control) only or a xenogeneic collagen matrix in addition (CAF + CMX = test). Visual analogue scales (VAS) and questionnaires were used for PROMs and the root coverage aesthetic score (RES) for professional aesthetic evaluations. RESULTS: VAS scores (patient satisfaction) amounted to 8.58 ± 1.86 (test) versus 8.38 ± 2.46 (control). Six patients preferred CAF + CMX concerning surgical procedure and aesthetics, six preferred CAF and 29 were equally satisfied. RES was 7.85 ± 2.42 for the test group versus 7.34 ± 2.90 for the controls. Root coverage (RC) was 76.28% for test and 75.05% for control defects. The mean increase in keratinized tissue width was higher in test (from 1.97 to 3.02 mm) than in controls (from 2.00 to 2.64 mm) (p = 0.0413). Likewise, test sites showed more gain in gingival thickness (0.52 mm) than control sites (0.27 mm) (p = 0.0023). Compared to 6 months, clinical outcomes were stable. CONCLUSIONS: Results for PROMs, RES and RC did not significantly differ between treatment groups. Thickness and width of keratinized tissue were enhanced following CAF + CMX compared to CAF alone.

Dimensional changes after immediate implant placement with or without simultaneous regenerative procedures: a systematic review and meta-analysis.

OBJECTIVE: To analyse alveolar ridge volume changes after immediate implant placement, with or without a regenerative technique. METHODS: Studies investigating the effect of immediate implant placement on ridge dimensional changes were identified through an electronic search conducted using MEDLINE (PubMed) and EMBASE. Weighted mean changes (WMC) between baseline and follow-up time were calculated and subgroup analysis was performed according to study design, evaluation method and regenerative strategies. RESULTS: After immediate implant placement alone WMC of RCTs showed a loss in width and height of 1.1 mm. After flapless immediate implant placement with immediate provisionalization and a graft WMC showed a loss in width and height of 1.02 mm and 0.79 mm, while after flapped immediate implant placement and a graft WMC showed a gain of 1.79 mm. After immediate implant placement plus a non-resorbable membrane WMC showed a loss in height of 0.07 mm. After immediate implant placement plus a resorbable membrane and a graft WMC showed a gain in height of 1.09 mm. CONCLUSIONS: Immediate implant placement does not seem to counteract alveolar ridge modelling after tooth extraction. Furthermore, the currently available evidence does not allow for any conclusive statements regarding the efficacy of a concomitant regenerative technique in preventing the amount of alveolar reduction.

Alveolar ridge preservation techniques: a systematic review and meta-analysis of histological and histomorphometrical data.

AIM: The aim of this article was to systematically review histological and histomorphometrical data from literature that provide information regarding the effect of alveolar ridge preservation procedures on healing after tooth extraction in humans. MATERIALS AND METHODS: The MEDLINE-PubMed and the Cochrane CENTRAL databases were searched up to September 2012; 38 papers were selected from 646 founded. A meta-analysis was performed regarding the variations in the mean percentage of Bone, Connective Tissue and Residual Graft Material between three different types of Procedures. RESULTS: The highest value regarding bone percentages is produced at 3 months by Procedures with Allografts (54.4%), while the lowest is obtained, at 5 months, by those using Xenografts (23.6%). Referring to connective tissue, the highest and lowest values are shown at 7 months, with Allografts (67%) and Alloplasts (27.1%), respectively. Regarding residual graft material, the lowest rates are displayed by Procedures with Allografts (12.4-21.11%), while those using Xenografts and Alloplasts showed the best results at 7 months (37.14 and 37.23%). No statistical difference was found. CONCLUSIONS: With the limitations due to the features of the selected papers, no major histological and histomorphometrical differences arose among different procedures or when compared to spontaneous healing. Thus, it might be argued that in preserved sites it is unnecessary to wait over 3 to 4 months prior to implant insertion.

Fresh extraction socket: spontaneous healing vs. immediate implant placement.

AIM: To evaluate the impact that immediate implant placement may have on bone remodelling in comparison with adjacent sockets left to heal spontaneously. MATERIALS AND METHODS: In a beagle dog model (N = 16 dogs), mandibular premolars were extracted, and implants were placed in each distal socket (test) with the corresponding mesial site left to heal undisturbed (control). Healing was assessed measuring both the vertical distance between buccal and lingual crest (B'L') and the width of buccal and lingual walls at different levels. Five healing periods were evaluated. Differences between means for each variable and for each healing period between test and control were compared (Kruskal-Wallis test; Friedman test). RESULTS: At 2 and 8 weeks of healing, the B'L' distance revealed significant higher values at test compared to control sites, being this difference three times higher at the end of the study (P < 0.05). In the test group, the width of the crest was reduced between baseline (0.37 [0.04]) and 8 weeks healing (0.13 [0.64]), demonstrating a 62% reduction of the initial width. These differences were not observed in the control group. CONCLUSIONS: Immediate implant placement into fresh extraction sockets may jeopardize the vertical bone remodelling of the socket. Furthermore, a tendency towards greater buccal horizontal resorption was observed in the most coronal aspect of the buccal bone crest.

Flap approaches in plastic periodontal and implant surgery: critical elements in design and execution.

AIM: To identify critical elements in design and execution of coronally advanced flap, lateral positioned flap and their variations for the treatment of facial gingival recessions or peri-implant soft tissue dehiscences. MATERIALS AND METHODS: Clinical studies were identified with both electronic and hand searches, and examined for the following aspects: flap design and incision techniques, flap elevation, root conditioning, flap mobility, flap stability and suturing. Moreover, prognostic factors for complete recession coverage were identified. RESULTS: Some critical elements are evident in flap design and execution: the dimension and the thickness of tissue positioned over the denuded roots; the use on root surface of enamel matrix derivate; the stability and suturing of the flap in a position coronal to the cemento-enamel junction. The pre-determination of the clinical cemento-enamel junction, smoking status, operator surgical skills and the compliance to a supportive care programme have a role in obtaining and maintaining a complete root coverage. CONCLUSIONS: Different flap approaches are available when performing periodontal plastic surgery, resulting in a great variability in clinical outcomes. The possibility of using pedicle flaps alone to achieve complete soft tissue coverage of facial implant dehiscence has not yet been investigated.

A randomized trial on the aesthetic outcomes of implant-supported restorations with zirconia or titanium abutments.

AIM: To evaluate the aesthetic outcomes of zirconia versus titanium abutments for single tooth implant-supported crowns in the anterior maxilla. MATERIAL & METHODS: A parallel, double blind clinical trial was conducted at the Complutense University (Madrid), where 38 patients were recruited. After random allocation (via computer-generated permuted blocks), either zirconia (test) or titanium (control) abutments were placed. Intra- and inter-group differences in aesthetic (main outcome), clinical, radiographical, and patient-centred outcomes were evaluated at baseline (crown placement) and at 1-year follow-up. RESULTS: At 1 year, 25 of the 30 randomized patients were analysed (11 test and 14 control). Using the Implant Crown Aesthetic Index (ICAI), the scoring at baseline and 1-year were 7.9 and 7.6 for the test group and 10.6 and 11.3 for the control group, respectively. These differences were not statistically significant (sample size non-contrasted). Patient satisfaction was similarly high in both groups (visual analogue scale 8.5). Furthermore, no differences were observed in the clinical or radiographical outcomes. Two abutment fractures were registered in the test group. CONCLUSIONS: The use of zirconia abutments demonstrated a tendency towards better aesthetic outcomes although the differences were not statistically significant. However, more technical complications were noted with the use of zirconia abutments.

Early healing of the alveolar process after tooth extraction: an experimental study in the beagle dog.

AIM: To describe the early healing events in the alveolar socket during the first 8 weeks of spontaneous healing after tooth extraction. MATERIALS AND METHODS: 16 adult beagle dogs were selected and five healing periods were analysed (4 h, 1 week, 2 weeks, 4 weeks, 8 weeks). Mandibular premolars were extracted and each socket corresponding to the mesial root was left to heal undisturbed. In each healing period, three animals were euthanatized, each providing four study sites. Healing was assessed by descriptive histology and by histometric analysis using as landmarks: the vertical distance between buccal and lingual crest (B'L') and the width of buccal and lingual walls at three different levels. Differences between means for each variable for each healing period were compared (ANOVA; p < 0.05). RESULTS: B'L' at baseline was 0.45 (0.18) mm and decreased during the healing period to a final value of 0.18 (0.08) mm. The lingual width (Lw) remains almost unchanged while the buccal width (Bw) at 1 (Bw1) and 2 (Bw2) mm was reduced in about 40% of its initial value. CONCLUSIONS: Minor vertical bone reduction in both the buccal and lingual socket walls were observed. A marked horizontal reduction of the buccal bone wall was observed mostly in its coronal aspect.

Treatment of gingival recession defects with a coronally advanced flap and a xenogeneic collagen matrix: a multicenter randomized clinical trial.

AIM: To evaluate the clinical outcomes of the use of a xenogeneic collagen matrix (CM) in combination with the coronally advanced flap (CAF) in the treatment of localized recession defects. MATERIAL & METHODS: In a multicentre single-blinded, randomized, controlled, split-mouth trial, 90 recessions (Miller I, II) in 45 patients received either CAF + CM or CAF alone. RESULTS: At 6 months, root coverage (primary outcome) was 75.29% for test and 72.66% for control defects (p = 0.169), with 36% of test and 31% of control defects exhibiting complete coverage. The increase in mean width of keratinized tissue (KT) was higher in test (from 1.97 to 2.90 mm) than in control defects (from 2.00 to 2.57 mm) (p = 0.036). Likewise, test sites had more gain in gingival thickness (GT) (0.59 mm) than control sites (0.34 mm) (p = 0.003). Larger (≥3 mm) recessions (n = 35 patients) treated with CM showed higher root coverage (72.03% versus 66.16%, p = 0.043), as well as more gain in KT and GT. CONCLUSIONS: CAF + CM was not superior with regard to root coverage, but enhanced gingival thickness and width of keratinized tissue when compared with CAF alone. For the coverage of larger defects, CAF + CM was more effective.