Quintessence International, 02/2021

Objective: To describe how to perform, in a simple manner, a digital wax-up with open source software for a clinical application involving direct composite resin restorations. Report: The clinical technique described presents a simple and highly predictable way of performing direct restorations with the help of a digital wax-up made with open source software. It uses an open source digital tooth library to reestablish a more harmonious smile architecture, specifically of teeth that were worn due to parafunction, and restored with direct composite resin restorations. Conclusions: Thanks to the technology that was used in this case, fast, affordable and accurate results could be obtained. In addition, digital files can be stored, saving material, time, and space, and allowing identical replication of the work either virtually or printed at any time, if needed. (Quintessence Int 2021;52:104–110; doi: 10.3290/j.qi.a45426) Schlagwörter: 3D printing, composite resin, digital dentistry, digital wax-up, direct restoration, wax-up

Objective: Retrograde peri-implantitis (RPI) is defined as bone loss around an osseointegrated implant apex that usually appears within the first few months of its placement. This retrospective study aimed to evaluate the relationships between RPI and demographic factors, local bone and intraoral factors, and implant and surgery-related factors. Method and materials: A retrospective study was conducted in 116 patients with a total of 369 implants placed between January and June 2019. The associations between RPI and the following data were evaluated: location of the recipient site, bone quality, reason for previous tooth loss, condition of adjacent teeth, marginal bone loss, immediate or late placement of implants, implant brand and size, activation of lesions, and treatment modality. Results: Among the 14 (3.8%) implants that showed RPI, 10 (5.8%) were in the maxilla and four (?2.0%) were in the mandible, which were detected before prosthetic loading. There was no significant difference in terms of RPI between the arches. Of the 14 RPI implants, four (28.?6%) were placed into a previously periapical lesion site, three (21.4%) had endodontically treated adjacent teeth, two (14.3%) were immediately placed following extraction, three (?21.4%) revealed marginal bone loss, and one (7.1%) was lost at the abutment connection. Eight RPI implants healed spontaneously, while the remaining six were subjected to treatment (P = .05). Conclusion: Local bone and intraoral factors, particularly the reason for tooth loss at the recipient site and the condition of the adjacent teeth, had stronger effects on RPI than other factors. (Quintessence Int 2021;52:112–121; doi: 10.3290/j.qi.a45264) Schlagwörter: adjacent teeth, apical peri-implantitis, implant, implant failure, periapical lesion, retrograde peri-implantitis

Objective: The aim of this systematic review and meta-analysis was to evaluate the impact of supportive peri-implant therapy (SPIT) on the rates of peri-implant diseases and peri-implant marginal bone loss. ?Data sources: The guidelines of PRISMA statement were followed in searching for randomized controlled trials, controlled clinical trials, and retrospective studies in several electronic databases and reference lists. The Cochrane Collaboration’s Risk of Bias tools for nonrandomized studies were used to assess the risk of bias. Data were analyzed using statistical software. ?A total of 159 studies were identified. Five trials, with 1,570 implants in 617 patients, met the inclusion criteria. Overall meta-analysis showed significantly reduced rates of peri-implantitis with SPIT compared with non-SPIT at implant and patient levels. Peri-implant mucositis was significantly reduced with SPIT at implant level only. Peri-implant marginal bone loss was significantly reduced in patients with SPIT compared to those who did not attend SPIT. Conclusion: SPIT can significantly reduce the rate of peri-implantitis and marginal bone loss. The evidence on the role of SPIT in reducing the rate of peri-implant mucositis, on the other hand, remains limited. Further well-designed studies on the impact of SPIT on implant treatment outcome are still needed. Clinical significance: There is a need to adopt a SPIT regimen for patients receiving implant therapy to reduce the rate of peri-implant diseases and marginal bone loss. This need should be stipulated in the patient information and consent forms prior to implant therapy. (Quintessence Int 2021;52:122–131; doi: 10.3290/j.qi.a45428) Schlagwörter: dental implants, meta-analysis, peri-implant marginal bone loss, review, supportive peri-implant therapy

The extraction of a tooth with root resorption can be a complicated procedure and can result in the removal of a significant amount of alveolar bone. In the anterior maxilla, esthetic rehabilitation of damaged sites with implant-supported crown could require multiple surgeries. Patients often ask for an alternative, and minimally invasive treatments are generally preferred. In this paper, a clinical case of implant-supported crown in a site affected by root resorption is described. Immediate implant was placed leaving some root fragments in the osteotomy site, thus avoiding invasive extractive surgeries. A minimally invasive flapless technique with a computer-guided implant placement procedure was used. After ?8 years, clinical and radiologic data were stable, gingival tissues around the implant appeared healthy, no dark translucency appeared through marginal gingiva around the implant, and there was no pathologic probing pocket depth ?or bleeding on probing. In the presence of root resorption and ankylosis, computer-guided surgery could be helpful to prepare a precise implant site through various tissues, such as partially resorbed root remnants. (Quintessence Int 2021;52:132–137; doi: 10.3290/j.qi.a45432) Schlagwörter: digital dentistry, implants, prosthodontics, tooth erosion, tooth wear

Objective: The present systematic review aimed to assess the efficacy of photobiomodulation (PBM) therapy on neurosensory recovery of patients with inferior alveolar nerve injury following third molar surgery or dental implant placement. Method and materials: An electronic search was carried out in Scopus, Embase, Medline, PubMed, Web of Science, Cochrane Library, and Google Scholar databases. Among 1,122 identified papers, seven articles (three RCTs, one observational study, and three case series) met the inclusion criteria. Results: Time lapse from nerve injury to the onset of PBM therapy varied widely from 2 days to 4 years. The number of patients in each study ranged between 4 and 74. In the majority of the studies, PBM was done using a diode laser at wavelengths ?in the range of 808 to 830 nm with power of 5 to 500 mW and radiation dose of 3 to 244 J/cm2. Two out of three RCTs found significant neurosensory recovery in the patients who received PBM therapy compared to the controls. The observational study and all case series reported significant improvement in the neurosensory status following PBM therapy. The degree of neurosensory recovery was found to be greater in younger patients and those who received the treatment within 6 months following the injury. Conclusions: Due to the limited number of well-designed RCTs and small number of patients in each study, it is not possible to make a clear conclusion about the efficacy of PBM therapy on neurosensory recovery in patients with inferior alveolar nerve injury following third molar or implant procedures. Considering the possibility of spontaneous inferior alveolar nerve recovery during this period, the conclusion based on the studies with no control group should be interpreted with caution. (Quintessence Int 2021;52:140–153; doi: 10.3290/j.qi.a45430) Schlagwörter: dental implants, inferior alveolar nerve, low-level light therapy, nerve regeneration, oral surgical procedures, photobiomodulation therapy

Objective: Nasal airway obstruction affects up to one-third of Americans and is one of the most common complaints by patients to otolaryngologists. Nasal airway obstruction and obstructive sleep apnea syndrome (OSAS) are closely related. The aim of this study was to use the 3D imaging software, ITK-SNAP as a platform to define a gold standard for anatomically accurate boundaries of the nasal airway in 3D CBCT and to create a more reliable and precise 3D CBCT segmentation of the nasal airway for assisting diagnosis, treatment, and monitoring of nasal airway obstruction and OSAS. Method and materials: After review of the literature to identify established parameters using CBCT and CT technology for the segmentation of the nasal airway, and the existing drawbacks, a gold standard for locating the anatomical boundaries of the nasal airway using CBCT is proposed. This new method aims at standardization of segmentation and quantification, allowing for more reliable comparison between studies. ITK-SNAP software was used to segment three CBCT samples of healthy patients aged 21 to 59 years, who were patients of record, with CBCT obtained for either orthodontic, endodontic, or prosthodontic treatment planning purposes. Results: The literature search identified 11 studies describing nasal airway parameters utilizing CBCT and CT. A great variation was detected on where the anatomical boundaries for the nasal airway were selected. A new standard in the identification of anatomical boundaries of the nasal airway is proposed for consistent segmentation and quantification using 3D CBCT by using the following landmarks: the inferior ANS-PNS border, the anterior nares border, the posterior sella-PNS border, and superiorly the border in alignment with the base of the skull (excluding the ostia, frontal, ethmoidal, and sphenoidal air cells). The three segmented samples were volumetrically measured, and statistically analyzed. The mean average Hounsfield unit intensity using the CBCT samples in this study was 629 with a standard deviation of 190. Conclusion: The literature indicates a lack of a gold standard using CBCT technology for the segmentation of the nasal airway. With the proposed standard in this study, it is possible to quantify the nasal airway volume and thereby its reduction. For the general dental practitioner, this is an important aspect during the evaluation of overall airway assessment. This information can be useful in the diagnosis and treatment of airway compromised dental patients. (Quintessence Int 2021;52:154–164; doi: 10.3290/j.qi.a45429) Schlagwörter: CBCT, COVID-19, nasal airway obstruction, nasal airway volume, obstructive sleep apnea, segmentation

Ehlers-Danlos syndromes (EDS) are a group of diverse hereditary connective tissue disorders. Various EDS subtypes present as different diseases. Periodontitis of early onset is a major criterion of periodontal EDS (pEDS). This article reports the clinical case of two siblings, young adults, who came to the clinic for diagnosis and treatment of periodontal disease. The patients had already been diagnosed with pEDS several months earlier after being referred for genetic testing by a dermatologist. It should be noted that in these siblings pEDS had been misinterpreted for years by health care specialists despite the patients’ periodontal disease, which had appeared at the age of 3 years. The subsequent effects of periodontal disease in these patients jeopardized the survival prognosis of their teeth. It may be stated that, in spite of pEDS’s status as a rare syndrome, the dental practitioner can play a key role in the early diagnosis by responding appropriately to periodontal manifestations at early stages. (Quintessence Int 2021;52:166–174; doi: 10.3290/j.qi.a45263) Schlagwörter: connective tissue, early diagnosis, Ehlers-Danlos syndromes, periodontal disease, siblings

At present, the most important criterion for the size selection of interdental brushes is the PHD-value (passage hole diameter) according to the ISO standard for interdental brushes ISO 16409:2016. The PHD size range of commercially available products currently lies between 0.6 and 5.2 mm. With the exceptions of special situations, a range between 0.7 and 2.9 mm is sufficient for clinical routine. As most products have longer filaments nowadays, one brush can often be applied for two PHD intervals. Consequently, adequate patient counseling and the individual selection of the appropriate interdental brushes can generally be achieved with an assortment of 12 systematically arranged interdental brush sizes. An application example is the “Heidelberg set” described herein. It is crucial that the correct choice of size is based upon continuously rising PHD-values, and not upon parameters such as stem size, outer diameter of filaments, or similar, as these do not allow for a reliable conclusion regarding the interdental passage. The usage of ISO sizes is also not recommendable due to their insufficient size differentiation. (Quintessence Int 2021;52: 176–186; doi: 10.3290/j.qi.b872241; Revised from an article originally published (in German) in Parodontologie 2020;31(1)37–49) Schlagwörter: Heidelberg-Set, interdental brush, interdental hygiene, passage hole diameter, mechanical plaque control