Prognosis of Single Implant-Supported Prosthesis in Patients With Primary Sjögren's Syndrome: A Five-Year Prospective Clinical Study.

BACKGROUND: Primary Sjögren's syndrome (pSS) is a chronic systemic autoimmune disease characterized by hyposalivation. Currently, there is limited evidence for the prognosis of dental implant treatment in Sjögren's syndrome. AIM/HYPOTHESIS: We hypothesized comparable clinical outcomes of implant-supported restorations in pSS-patients and control subjects, and improvement in oral health-related quality of life 5 years after restoration. MATERIAL AND METHODS: Patients with pSS and matched (age, gender, and tooth region) control group were recruited between June 2016 and March 2020. The clinical and radiological examination were performed, and patient-reported oral health impact profile (OHIP-49) questionnaire was used 2 months (baseline), 1, 3, and 5 years after prosthetic treatment. RESULTS: We included 23 patients with pSS and 24 matched control subjects (all women, mean age: 57.1 years). The overall DMFT (decayed-missed-filled-tooth) was significantly higher (p = 0.008), symptoms of dry mouth were more severe (p = 0.001), and unstimulated and chewing-stimulated saliva flow rates were significantly lower (p < 0.001) in pSS than in control group. All implants survived with no implant mobility. At implant sites, the plaque index and probing depths did not differ (p = 0.301 and 0.446, respectively), but the gingival index was significantly higher (p = 0.003) in pSS than control group. The mean marginal bone loss, prosthetic complications, and clinician-reported aesthetic outcomes were similar in both groups after 5 years. The OHIP scores were significantly higher in the pSS than control group (p < 0.001) but reduced significantly in both groups (p = 0.026). CONCLUSION: Replacement of missing single teeth with dental implants was successful in patients with pSS 5 years after restoration.

Characterization of patients with odontogenic necrotizing soft tissue infections in the head and neck area. A retrospective analysis.

OBJECTIVE: Necrotizing soft-tissue infection (NSTI) in the head and neck area may develop from odontogenic infections. The aim of this study was to characterize patients with NSTI in the head and neck with odontogenic origin in a well-defined prospectively collected cohort. MATERIAL AND METHODS: Patients with NSTI in the head and neck, hospitalized between 2013 and 2017 at Copenhagen University Hospital and registered in the Scandinavian INFECT database were included. Medical records of identified patients and from the INFECT database were screened for a defined set of data including the primary focus of infection, comorbidities, predisposing factors, clinical and radiographic diagnostics, course of treatment, and treatment outcome. RESULTS: Thirty-five patients with NSTI in the head and neck area were included in the study. A total of 54% had odontogenic origin, primarily from mandibular molars, and 94% had radiographic signs of infectious oral conditions. Overall, comorbidities were reported in 51% with cardiovascular disease being the most prevalent. In 20%, no comorbidities or predisposing conditions could be identified. The overall 30-day mortality rate was 9%. CONCLUSIONS: More than half of NSTI cases in the head and neck region had an odontogenic origin, and special attention should be paid to infections related to mandibular molars.

Group 1 ITI Consensus Report: The role of bone dimensions and soft tissue augmentation procedures on the stability of clinical, radiographic, and patient-reported outcomes of implant treatment.

OBJECTIVES: The aims of Working Group 1 were to address the role (i) of the buccolingual bone dimensions after implant placement in healed alveolar ridge sites on the occurrence of biologic and aesthetic complications, and (ii) of soft tissue augmentation (STA) on the stability of clinical, radiographic, and patient-related outcomes of implant treatments. MATERIALS AND METHODS: Two systematic reviews were prepared in advance of the Consensus Conference and were discussed among the participants of Group 1. Consensus statements, clinical recommendations, recommendations for future research, and reflections on patient perspectives were based on structured group discussions until consensus was reached among the entire group of experts. The statements were then presented and accepted following further discussion and modifications as required by the plenary. RESULTS: Dimensional changes of the alveolar ridge occurred after implant placement in healed sites, and a reduction in buccal bone wall thickness (BBW) of 0.3 to 1.8 mm was observed. In healed sites with a BBW of <1.5 mm after implant placement, increased vertical bone loss, and less favorable clinical and radiographic outcomes were demonstrated. Implants with buccal dehiscence defects undergoing simultaneous guided bone regeneration, showed less vertical bone loss, and more favorable clinical and radiographic outcomes, compared to non-augmented dehiscence defects during initial healing. At healthy single implant sites, probing depths, bleeding and plaque scores, and interproximal bone levels evaluated at 1 year, remained stable for up to 5 years, with or without STA. When single implant sites were augmented with connective tissue grafts, either for soft tissue phenotype modification or buccal soft tissue dehiscence, stable levels of the soft tissue margin, and stable or even increased soft tissue thickness and/or width of keratinized mucosa could be observed from 1 to 5 years. In contrast, non-augmented sites were more prone to show apical migration of the soft tissue margin in the long-term. Favorable aesthetic and patient-reported outcomes after STA were documented to be stable from 1 to 5 years. CONCLUSIONS: It is concluded that dimensional changes of the alveolar ridge occur after implant placement in healed sites and that sites with a thin BBW after implant placement are prone to exhibit less favorable clinical and radiographic outcomes. In addition, it is concluded that STA can provide stable clinical, radiographic, aesthetic, and patient-reported outcomes in the medium and long-term.

Cerebral abscesses with odontogenic origin: a population-based cohort study.

OBJECTIVES: Recent studies have indicated that cerebral abscess (CA) patients with odontogenic origin are on the rise. However, CA patients are often poorly characterized and with an unknown etiologic background. The purpose of this study is to identify and characterize CA patients that may have an odontogenic origin based on microbiologic, radiographic, and/or clinical findings. MATERIALS AND METHODS: This is a population-based cohort study analyzing retrospective and prospective data from CA patients. Radiographic examinations of panoramic radiographs (PRs) or computed tomography (CT) scans were conducted. CA patients characterized with odontogenic origin required the fulfilment of the following criteria on admission: (1) Oral pathologic conditions were the only bacterial infections present, (2) oral microorganisms were isolated in the purulent exudate from the brain, and (3) radiographically and/or clinical recordings of oral pathologic conditions. RESULTS: A total of 44 patients could be included in this study of which 25 (57%) were characterized as having CA with a likely odontogenic origin. Type two diabetes (T2D) (p = 0.014) and microorganisms of the Streptococcus anginosus group (SAG) (p < 0.01) were overrepresented in patients with CAs of odontogenic origin. CONCLUSIONS: Odontogenic infections may cause CAs to a greater extent than previously assumed. T2D was overrepresented among patients with odontogenic CA. When microorganisms of the SAG were isolated from the brain pus, CA patients had a predisposing odontogenic or sinus infection. CLINICAL RELEVANCE: The identification of patients with a likely odontogenic CA will contribute to understanding the etiology of the infectious disease and highlighting the importance of preserving oral health.

Narrow diameter implants to replace congenital missing maxillary lateral incisors: A 1-year prospective, controlled, clinical study.

OBJECTIVES: To report the clinical, radiographic, esthetic, and patient-reported outcomes after placement of a newly developed narrow-diameter implant (NDI) in patients with congenitally missing lateral incisors (MLIs). MATERIALS AND METHODS: Patients with MLIs with a mesio-distal distance between the canine and the central incisor of 5.9-6.3 mm received a dental implant with a diameter of 2.9 mm (Test), while a diameter of 3.3 mm (Control) was used when the distance was 6.4-7.1 mm. After healing, a cement-retained bi-layered zirconia crown was fabricated. At the 1-year follow-up (T2), implant survival rate, marginal crestal bone level (CBL) changes, biological and technical complications were registered. The esthetic outcome was assessed by using the Copenhagen index score, and the patient-reported outcomes were recorded using the OHIP-49 questionnaire. RESULTS: One hundred patients rehabilitated with 100 dental implants Ø0.9 mm (n = 50) or Ø3.3 mm (n = 50) were included. One Ø3.3 mm implant was lost, and seven patients dropped out of the study, yielding an implant survival rate of 99% (p = 1.000). At T2 a. CBL of -0.19 ± 0.25 mm (Test) and -0.25 ± 0.31 mm (Control) was detected, with no statistically significant difference between the groups (p = .342). Good to excellent esthetic scores (i.e., 1-2) were recorded in most of cases. Technical complications (i.e., loss of retention, abutment fracture, and chipping of veneering ceramic) occurred once in three patients with no statistically significant difference between the groups (p > .05). OHIP scores did not differ significantly at follow-ups between groups (p = .110). CONCLUSION: The use of Ø2.9 mm diameter implants represents as reliable a treatment option as Ø3.3 mm implants, in terms of CBL changes, biological and technical complications. Favorable esthetics and patient-reported outcomes were recorded for both groups.

Implant treatment after traumatic tooth loss: A systematic review.

BACKGROUND/AIMS: Treatment after traumatic tooth loss is challenging and is currently guided by expert opinion and the individual patient situation. The aim of this study was to provide an overview on the outcome of dental implant treatment in the anterior maxilla after traumatic tooth loss, based on a systematic review of the existing evidence. MATERIALS AND METHODS: A systematic search of the literature was performed on PubMed, Cochran Library and Web of Science following the PRISMA guidelines based on a structured research question (PICO). All clinical studies of five patients or more with follow-up of at least 1 year after implant loading were included. Patients were at least 18 years of age. Cohen's Kappa-coefficient was calculated. The Newcastle-Ottawa Scale was applied to assess the quality of the included studies. Descriptive statistical methods were applied. RESULTS: Nine hundred and ninety-nine articles were identified through the systematic search. Finally, six articles were eligible for inclusion. The studies comprised prospective and retrospective cohort studies and case series. From these, 96 patients with 120 implants were included. The age ranged from 18 to 59 years. The survival rates of implants and superstructures were 97% and 95%, respectively, after a mean follow-up of 3.5 years. Mean marginal bone resorption was 0.56 mm (range 0.21-1.30 mm). Complication rates were 7% and 11% on implant and superstructure level, respectively. Patient-reported outcome measures and objective evaluations showed a high level of satisfaction with the aesthetic outcome. Bone augmentation was performed in 60 implant sites. Three patients underwent pre-surgical orthodontic treatment. The maxillary central incisor was the most frequently replaced tooth (70%). CONCLUSIONS: This systematic review revealed a low level of evidence on the outcome of dental implant treatment after traumatic tooth loss. Systematic reporting of treatment outcomes of tooth replacements after dental trauma is highly encouraged to further guide dentists for the benefit of these challenging patients.

Need for lateral bone augmentation at two narrow-diameter implants: A prospective, controlled, clinical study.

OBJECTIVES: To detect the potential influence of implant diameter and anatomic factors on the need for bone augmentation procedures (BAPs) when replacing congenitally missing lateral incisors (MLIs). MATERIALS AND METHODS: Patients with congenitally missing MLIs with a mesio-distal distance between the canine and the central incisor of 5.9-6.3 mm received a Ø2.9 mm implant while Ø3.3 mm implants were placed when the distance was 6.4-7.1 mm. The following linear measurements were recorded using a calliper: width of the alveolar process (WAP), width of the bony alveolar ridge (WAR) and thickness of the facial bone after implant osteotomy (TFB). Guided bone regeneration was performed in case of fenestration- or dehiscence-type defects or a thin TFB (<1.7 mm). RESULTS: Fifty Ø2.9 mm and 50 Ø3.3 mm were included in 100 patients. WAP and WAR did not differ between the groups (p > .05). TFB was statistically significant larger in the Ø2.9 group (1.75 ± 0.59 mm) compared to the Ø3.3 group (1.5 ± 0.63 mm) (p = .041). Fenestration-type defects (p = .005) and a thin facial bone wall (p = .045) was observed more frequently in the Ø3.3 compared to the Ø2.9 group. Correspondingly, BAP was indicated more frequently in the Ø3.3 compared to the Ø2.9 group (p = .017). WAP, MD and WAR were statistically significant correlated to the need for BAP (p < .001). As independent variable, only WAR influenced the probability of BAP (p < .001). CONCLUSION: The use of 2.9 diameter implants was correlated to a reduced frequency of BAP compared to 3.3 mm implants, without reaching a statistically significant difference. Measurement of the WAP provides the clinician useful information to predict BAP.

Fully versus conventionally guided implant placement by dental students: A randomized controlled trial.

OBJECTIVE: To compare fully guided with conventionally guided implant surgery performed by dental students in terms of deviation of actual implant position from an ideal implant position. MATERIALS AND METHODS: Twenty-five patients in need of 26 straightforward implant-supported single crowns were randomly allocated to a fully guided (FG, n = 14) or a conventionally guided (CG, n = 12) implant surgery. In the preoperative CBCTs, 3 experienced investigators placed a virtual implant in the ideal position, twice, allowing deviational analysis in the facio-lingual (coronal) and mesio-distal (sagittal) planes for 7 parameters. Facio-lingual crestal deviation, facio-lingual apical deviation, facio-lingual angular deviation, mesio-distal crestal deviation, mesio-distal apical deviation, mesio-distal angular deviation, and vertical deviation between the ideal, virtually placed position and actual implant position for the FG and CG groups were compared statistically (p < .05). RESULTS: Statistically significant differences between ideal and actual implant position were only seen for the facio-lingual apical deviation (p = .047) and for the facio-lingual angular deviation (p = .019), where the CG group deviated more from the ideal position than the FG group. The 5 other examined variables did not show any significant differences, and none of the implants in the FG group and CG group were placed in conflict with the clinical guidelines. CONCLUSIONS: The present study reported no difference in 5 out of 7 deviational parameters concerning actual implant position in relation to ideal implant position between a FG and CG implant placement protocol performed by dental students. Facio-lingual angular deviation and apical deviation were lower, when a FG protocol was followed. All implants were positioned according to clinical guidelines.

Soft tissue management at implants: Summary and consensus statements of group 2. The 6th EAO Consensus Conference 2021.

OBJECTIVES: The task of working Group 2 at the 6th Consensus Meeting of the European Association for Osseointegration was to comprehensively assess the effects of soft tissue augmentation procedures at dental implant sites on clinical, radiographic and patient-reported outcome measures (PROMs) including an overview on available outcome measures and methods of assessment. MATERIALS AND METHODS: Three systematic reviews and one critical review were performed in advance on (i) the effects of soft tissue augmentation procedures on clinical, radiographic and aesthetic outcomes, (ii) reliability and validity of outcome measures and methods of assessment and (iii) PROMs applied in clinical studies for soft tissue augmentation procedures at dental implant sites. Major findings, consensus statements, clinical recommendations and implications for future research were discussed in the group and approved during the plenary sessions. RESULTS: The four reviews predominantly revealed: Soft tissue augmentation procedures in conjunction with immediate and delayed implant placement result in superior aesthetic outcomes compared to no soft tissue augmentation in the zone of aesthetic priority. Soft tissue augmentation procedures have a limited effect on marginal bone level changes compared to implant sites without soft tissue augmentation. Clinically relevant parameters (gingival index, mucosal recession) and plaque control improve at implant sites when the width of keratinised mucosa is increased. A variety of aesthetic indices have been described with good reliability. Pink Esthetic Score and Complex Esthetic Index are the most validated aesthetic indices for single implants, though. Superimposed digital surface scans are most accurate to assess profilometric tissue changes. PROMs following soft tissue augmentation procedures have been assessed using various forms of questionnaires. Soft tissue augmentation had a limited effect on PROMs. CONCLUSIONS: Soft tissue augmentation procedures are widely applied in conjunction with implant therapy. Depending on the indication of these interventions, clinical, radiographic and aesthetic outcomes may improve, whereas the effect on PROMs is limited.

The sandwich osteotomy technique to treat vertical alveolar bone defects prior to implant placement: a systematic review.

OBJECTIVES: The aim of this systematic review was to investigate the predictability of the sandwich osteotomy technique to provide sufficient alveolar bone height for dental implant therapy in vertically atrophic jaws. MATERIAL AND METHODS: A MEDLINE (Pubmed), EMBASE and Cochrane Library electronic search and a manual search were performed until July 2018. Any clinical study published in English, reporting data on at least 10 patients rehabilitated with implant-supported dental prostheses after vertical ridge augmentation by means of the sandwich osteotomy technique and followed for at least 12 months after loading, was included. Data on study and patients' characteristics, interventions provided, implant and prostheses survival rates and complications were extracted from the included studies. Each study design was evaluated using the Cochrane Collaboration's tool for assessing risk of bias. RESULTS: Initially, 415 records were identified, from which 10 full-text articles could be included in the final qualitative analysis. Implant survival rate after a mean follow-up of 3.7 years (median: 3 years; range: 1-7 years) was 94% (median: 93%; range: 91-100%). Peri-implant mean marginal bone resorption was 1.6 mm (median: 1.4 mm; range: 0.6-4.7 mm). The calculated mean alveolar bone height available at the time of implant placement was 11.3 mm (median: 11.5 mm; range: 7.8-16 mm). A temporary sensory disturbance of the inferior alveolar nerve was the most commonly reported complication following the sandwich osteotomy. CONCLUSIONS: The present systematic review documents that implant survival rate after mandibular vertical ridge augmentation using the sandwich osteotomy technique is high after up to 5 years of loading. The complication rate can be considered moderate and has predominantly a transient nature. Data on the long-term behavior of the augmented bone and inserted implants are missing. CLINICAL RELEVANCE: The present technique can be considered a reliable treatment option in cases of moderate vertical bone deficiency of the posterior mandible to provide suitable conditions for later implant placement. Intra- and post-operative complications do not seem to jeopardize the final outcome.

Implant-supported 2-unit cantilevers compared with single crowns on adjacent implants: A comparative retrospective case series.

STATEMENT OF PROBLEM: The replacement of 2 adjacent missing teeth remains a clinical challenge. Among the different treatment options, the use of a single implant to support a 2-unit cantilever fixed dental prosthesis (FDP) has been proposed in situations of limited mesiodistal space, even though the evidence for its use is low. PURPOSE: The purpose of this retrospective comparative case series was to evaluate hard and soft peri-implant tissues in patients with 2 adjacent missing teeth in the anterior area (incisors or canines) rehabilitated with implant-supported 2-unit cantilevers or single crowns on adjacent implants. MATERIAL AND METHODS: Twenty-three from a cohort of 34 patients rehabilitated with 2-implant systems between September 2006 and November 2015 with 2-unit cantilever FDPs (test group) (n=16) or 2 adjacent dental implants supporting single crowns (control group) (n=7) were available for follow-up. At the baseline and follow-up examinations, the implant survival rate, peri-implant probing pocket depth, marginal bone level (MBL), as well as papilla scores and prosthetic outcomes from the Copenhagen Index Score were recorded and evaluated. RESULTS: One implant in the control group was lost during the observation period, leading to an overall implant survival rate of 97%. Mean peri-implant probing depths were low (≤5 mm) in both the groups. Stable marginal bone levels were detected around adjacent implants and around implants supporting cantilevers. Medium to high esthetic scores were obtained in most patients. Papilla index scores were high (score 1 and 2) in both the groups. Finally, no technical complications were recorded. CONCLUSIONS: The use of a single-implant-supported 2-unit cantilever FDP in anterior sites is a valid treatment option compared with 2 adjacent implants, especially when the available mesiodistal space is limited.

Timing of implant placement after traumatic dental injury.

Dental implants are reliable to replace teeth lost because of traumatic dental injury. However, dental implants behave like ankylosed teeth and should not be placed in growing individuals because of the risk of infraposition. This risk may be reduced by ensuring arrested skeletal growth and ideal incisal support. The timing of implant placement may be immediate, early, conventional, or late and is determined by the extent of the trauma, remaining growth, and conditions of the hard and soft tissues. Timing should allow an observation period to properly evaluate the prognosis of concomitantly traumatized neighboring teeth. Orthodontic alignment is often necessary after traumatic dental injury in young individuals to provide symmetric dental conditions around the facial midline, to allow implant placement in the correct 3-dimensional position for the later prosthetic reconstruction, and to ensure sufficient mesiodistal space that leaves a minimum of 1.5 mm of healthy alveolar bone between the future implant and neighboring teeth. Space and stable occlusion should be maintained by bonded retainers and a splint used during the night. A partial prosthesis is usually recommended as a temporary replacement. If a fixed provisional prosthesis is required, it is crucial that it does not interfere with the remaining growth and incisal support and allows proper oral hygiene.

Group 1 ITI Consensus Report: The influence of implant length and design and medications on clinical and patient-reported outcomes.

OBJECTIVES: The aim of Working Group 1 was to address the influence of different local (implant length, diameter, and design) and systemic (medications) factors on clinical, radiographic, and patient-reported outcomes in implant dentistry. Focused questions on (a) short posterior dental implants (≤6 mm), (b) narrow diameter implants, (c) implant design (tapered compared to a non-tapered implant design), and (d) medication-related dental implant failures were addressed. MATERIALS AND METHODS: Four systematic reviews were prepared in advance of the Consensus Conference and were discussed among the participants of Group 1. Consensus statements, clinical recommendations, and recommendations for future research were based on structured group discussions until consensus was reached among the entire expert Group 1. The statements were then presented and accepted following further discussion and modifications as required by the plenary. RESULTS: Short implants (≤6 mm) revealed a survival rate ranging from 86.7% to 100%, whereas standard implant survival rate ranged from 95% to 100% with a follow-up from 1 to 5 years. Short implants demonstrated a higher variability and a higher Risk Ratio [RR: 1.24 (95% CI: 0.63, 2.44, p = 0.54)] for failure compared to standard implants. Narrow diameter implants (NDI) have been classified into three categories: Category 1: Implants with a diameter of <2.5 mm ("Mini-implants"); Category 2: Implants with a diameter of 2.5 mm to <3.3 mm; Category 3: Implants with a diameter of 3.3 mm to 3.5 mm. Mean survival rates were 94.7 ± 5%, 97.3 ± 5% and 97.7 ± 2.3% for category 1, 2 and 3. Tapered versus non-tapered implants demonstrated only insignificant differences regarding clinical, radiographic, and patient-reported outcomes. The intake of certain selective serotonin reuptake inhibitors and proton pump inhibitors is associated with a statistically significant increased implant failure rate. The intake of bisphosphonates related to the treatment of osteoporosis was not associated with an increased implant failure rate. CONCLUSIONS: It is concluded that short implants (≤6 mm) are a valid option in situations of reduced bone height to avoid possible morbidity associated with augmentation procedures; however, they reveal a higher variability and lower predictability in survival rates. Narrow diameter implants with diameters of 2.5 mm and more demonstrated no difference in implant survival rates compared to standard diameter implants. In contrast, it is concluded that narrow diameter implants with diameters of less than 2.5 mm exhibited lower survival rates compared to standard diameter implants. It is further concluded that there are no differences between tapered versus non-tapered dental implants. Certain medications such as selective serotonin reuptake inhibitors and proton pump inhibitors showed an association with a higher implant failure rate.

Maxillary Sinus Floor Augmentation With Synthetic Bone Substitutes Compared With Other Grafting Materials: A Systematic Review and Meta-analysis.

OBJECTIVE: To test the hypotheses of no differences in implant treatment outcome after maxillary sinus floor augmentation (MSFA) with synthetic bone substitutes (SBS) compared with other grafting materials applying the lateral window technique. MATERIALS AND METHODS: A MEDLINE/PubMed, Embase and Cochrane Library search in combination with hand-search of selected journals was conducted. RESULTS: Five randomized controlled trials with low risk of bias fulfilled the inclusion criteria. SBS disclosed high survival rate of suprastructures and implants with no significant differences compared to autogenous bone graft or xenograft. Meta-analysis revealed a patient-based implant survival rate of 0.98 (confidence interval: 0.89-1.08), indicating no differences between SBS and xenograft. SBS demonstrated significant less newly formed bone compared with autogenous bone graft, whereas no significant difference was revealed as compared to xenograft. High implant stability values, limited periimplant marginal bone loss, and few complications were reported with SBS. CONCLUSIONS: There seem to be no differences in implant treatment outcome after MSFA with SBS compared to other grafting materials.

Autotransplantation of teeth to the anterior maxilla: A systematic review of survival and success, aesthetic presentation and patient-reported outcome.

BACKGROUND/AIM: Autotransplantation of teeth to the anterior maxilla may be indicated after trauma or in patients with congenitally missing teeth. The aim of this systematic review was to report the current evidence concerning survival and success rate, aesthetic outcome, and patient-reported outcome of autotransplanted teeth to the anterior maxilla. MATERIALS AND METHODS: A MEDLINE search followed by an additional hand search was performed to identify relevant literature. All levels of evidence except case reports were considered. Any publication reporting on 10 or more autotransplanted teeth to the anterior maxilla, and written in English were eligible for this systematic review. RESULTS: The systematic search identified 95 abstracts. Thirty-seven full-text articles were evaluated of which 17 could finally be included. Data on survival and success rate of the transplants could be extracted from 11 studies. Survival rates ranged between 93% and 100% (weighted mean: 96.7%, median: 100%) after 9 months to 22 years of observation (median: 8.75 years). No consensus regarding definition of success criteria of the transplants could be found in the literature. Two and four studies contained data on aesthetic and patient-reported outcomes, respectively. In general, they reported favourable aesthetic results and high patient satisfaction. CONCLUSION: The current available evidence suggests a high survival rate after autotransplantation of teeth to the anterior maxilla. However, the level of evidence is low. Limited data on aesthetic and patient-reported outcomes warrant additional research in this field.

Adverse reaction after hyaluronan injection for minimally invasive papilla volume augmentation. A report on two cases.

OBJECTIVES: To report two cases of adverse reaction after mucosal hyaluronan (HY) injection around implant-supported crowns, with the aim to augment the missing interdental papilla. MATERIAL AND METHODS: Two patients with single, non-neighbouring, implants in the anterior maxilla, who were treated within the frames of a randomized controlled clinical trial testing the effectiveness of HY gel injection to reconstruct missing papilla volume at single implants, presented an adverse reaction. Injection of HY was performed bilaterally using a 3-step technique: (i) creation of a reservoir in the mucosa directly above the mucogingival junction, (ii) injection into the attached gingiva/mucosa below the missing papilla, and (iii) injection 2-3 mm apically to the papilla tip. The whole-injection session was repeated once after approximately 4 weeks. RESULTS: Both patients presented with swelling and extreme tenderness with a burning sensation on the lip next to the injection area, after the second injection session. In one of the cases, a net-like skin discoloration (livedo reticularis) was also noted. The symptoms lasted for up to 7 days, and in both cases, symptoms resolved without any signs of skin or mucosal necrosis or any permanent damage. CONCLUSION: Most likely, water attraction over time by the highly hygroscopic HY, exerted progressively an external vascular compression and at least partial occlusion of neighbouring blood vessels. An infection or an allergic reaction seems unlikely, since all symptoms gradually disappeared within a week irrespective use of antimicrobials, while an allergic reaction most likely would not have been restricted to one side.

Can hyaluronan injections augment deficient papillae at implant-supported crowns in the anterior maxilla? A randomized controlled clinical trial with 6 months follow-up.

OBJECTIVES: The present randomized controlled trial aimed to assess the effect of hyaluronan (HY) injections to augment deficient interproximal papillae at implant-supported crowns in the anterior maxilla. METHODS: Twenty-two patients with a deficient papilla in the anterior maxilla next to an implant-supported crown were randomly assigned to receive twice either HY (test) or saline solution (control) injection. The following parameters were recorded prior to injection (baseline) and 3 and 6 months after injection: distance between the papilla tip and contact point (PT-CP), modified papilla index score (MPIS), and standard clinical periodontal parameters. Pain level after injection was recorded on a visual analogue scale (VAS). The deficient area was evaluated on clinical photographs, and the esthetic appearance was recorded on a VAS. Differences in mucosal volume were assessed after 3 months by intraoral scans. The bone level was assessed on periapical radiographs. RESULTS: No differences were observed between groups, neither at baseline nor at 3 and 6 months post-treatment. Mean PT-CP ranged between 1.8 mm and 2.3 mm without significant differences between groups or over time within groups; MPIS was 2 for all patients at all time points. Similarly, insignificant differences between groups or time points were observed for deficient area, gingival volume changes, bone level, and esthetic appearance. There were no differences in pain level between groups during injection, but discomfort after injection lasted longer in the test group. CONCLUSIONS: Injection of HY adjacent to maxillary anterior implant-supported crowns did not result in any clinical conspicuous volume augmentation of deficient papillae.

The resection angle in apical surgery: a CBCT assessment.

OBJECTIVES: The primary objective of the present radiographic study was to analyse the resection angle in apical surgery and its correlation with treatment outcome, type of treated tooth, surgical depth and level of root-end filling. MATERIALS AND METHODS: In the context of a prospective clinical study, cone beam computed tomography (CBCT) scans were taken before and 1 year after apical surgery to measure the angle of the resection plane relative to the longitudinal axis of the root. Further, the surgical depth (distance from the buccal cortex to the most lingual/palatal point of the resection plane) as well as the level of the root-end filling relative to the most coronal point of the cut root face was determined. Treated teeth were categorized into four groups (maxillary and mandibular anterior and posterior teeth). The final material comprised 62 treated roots in 55 teeth. RESULTS: The mean calculated resection angle of all roots was 17.7° ± 11.4° (range -9.6° to 43.4°). Anterior maxillary roots presented the highest mean angle (25.8° ± 10.3°) that was significantly different from the mean angle in posterior maxillary roots (10.7° ± 9.4°; p < 0.001) and from the mean angle in posterior mandibular roots (15.1 ± 9.8°; p < 0.05). In roots with a shallow resection angle (≤20°), the rate of healed cases was higher than in roots with an acute resection angle (>20°), however without reaching statistical significance (p = 0.0905). Angles did not correlate either with the surgical depth or with the retrofilling length. CONCLUSIONS: Statistically significant differences were observed comparing resection angles of different tooth groups. However, the angle had no significant effect on treatment outcome. CLINICAL RELEVANCE: Contrary to common belief, the resection angle in maxillary anterior teeth was greater than in the other teeth. The surgeon is advised to pay attention to the resection angle when bevelling maxillary anterior teeth in apical surgery.

Osteoclast-like cells on deproteinized bovine bone mineral and biphasic calcium phosphate: light and transmission electron microscopical observations.

OBJECTIVES: The occurrence of multinucleated giant cells (MNGCs) on bone substitute materials has been recognized for a long time. However, there have been no studies linking material characteristics with morphology of the MNGCs. The aim was to analyze the qualitative differences of MNGCs on two commercially available calcium phosphate bone substitute materials retrieved from bone defects. MATERIAL AND METHODS: Six defects were prepared bilaterally in the mandibular body of three mini pigs. The defects were randomly grafted with either deproteinized bovine bone mineral (DBBM) or biphasic calcium phosphate (BCP). After a healing period of four weeks, bone blocks were embedded in LR White resin. Three consecutive sections per defect were analyzed as follows: two with light microscopy using toluidine blue and tartrate-resistant acid phosphatase (TRAP) staining and one with transmission electron microscopy. RESULTS: Multinucleated giant cells appeared on both biomaterials. On BCP, MNGCs had a flat morphology and were not observed in resorption lacunae. On DBBM, the MNGCs appeared more round and were often found in shallow concavities. MNGCs on both biomaterials demonstrated a varying degree of TRAP staining, with a tendency toward higher staining intensity of MNGCs on BCP. At the ultrastructural level, signs of superficial dissolution of BCP together with phagocytosis of minor fragments were observed. MNGCs on the surface of DBBM demonstrated sealing zones and ruffled borders, both features of mature osteoclasts. CONCLUSION: MNGCs demonstrated distinctly different histological features depending on the bone substitute material used. Further research is warranted to understand the clinical implications of these morphological observations.

Impact of bone graft harvesting techniques on bone formation and graft resorption: a histomorphometric study in the mandibles of minipigs.

BACKGROUND: Harvesting techniques can affect cellular parameters of autogenous bone grafts in vitro. Whether these differences translate to in vivo bone formation, however, remains unknown. OBJECTIVE: The purpose of this study was to assess the impact of different harvesting techniques on bone formation and graft resorption in vivo. MATERIAL AND METHODS: Four harvesting techniques were used: (i) corticocancellous blocks particulated by a bone mill; (ii) bone scraper; (iii) piezosurgery; and (iv) bone slurry collected from a filter device upon drilling. The grafts were placed into bone defects in the mandibles of 12 minipigs. The animals were sacrificed after 1, 2, 4 and 8 weeks of healing. Histology and histomorphometrical analyses were performed to assess bone formation and graft resorption. An explorative statistical analysis was performed. RESULTS: The amount of new bone increased, while the amount of residual bone decreased over time with all harvesting techniques. At all given time points, no significant advantage of any harvesting technique on bone formation was observed. The harvesting technique, however, affected bone formation and the amount of residual graft within the overall healing period. Friedman test revealed an impact of the harvesting technique on residual bone graft after 2 and 4 weeks. At the later time point, post hoc testing showed more newly formed bone in association with bone graft processed by bone mill than harvested by bone scraper and piezosurgery. CONCLUSIONS: Transplantation of autogenous bone particles harvested with four techniques in the present model resulted in moderate differences in terms of bone formation and graft resorption.