The effect of surface roughening on the success of orthodontic mini-implants: A systematic review and meta-analysis.

INTRODUCTION: Orthodontic mini-implants are a widely accepted treatment modality in orthodontics; however, the failure rate is moderately high. Surface roughening is the golden standard in conventional oral implantology, and this may prove beneficial for orthodontic mini-implants as well. The objective of this systematic review is to assess the effect of surface roughening on the success rate of orthodontic mini-implants in both adolescent and adult patients undergoing orthodontic treatment. METHODS: Randomized studies comparing the success of surface-roughened and smooth, machined-surface orthodontic mini-implants were included. A literature search was conducted for 6 electronic databases (Pubmed/Medline, Embase, Cochrane, CINAHL, Web of Science, and Scopus), Clinical trial registry (https://www. CLINICALTRIALS: gov), and grey literature (Google Scholar). A manual search of the reference lists of included studies was performed. Two authors independently performed the screening, data extraction, risk of bias, and quality assessments. The risk of bias was assessed with the Cochrane risk-of-bias 2.0 Tool. Data were synthesized using a random effect model meta-analysis presented as a forest plot. The certainty in the body of evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation tool. RESULTS: A total of 4226 unique records were screened, and 6 of these were included in the quantitative analysis. Four additional articles were selected for a secondary outcome. A total of 364 orthodontic mini-implants were included in the primary outcome analysis. There was no statistically significant effect of surface roughening on the success of orthodontic mini-implants (odds ratio = 0.63 favoring roughened orthodontic mini-implants; 95% confidence interval, 0.35-1.14). The secondary outcome (ie, the overall failure rate of roughened orthodontic mini-implants) was 6% based on studies with high heterogeneity. Limitations of this study were the risk of bias, study imprecision, and possible publication bias, leading to a very low certainty in the body of evidence. CONCLUSIONS: There is very low-quality evidence that there is no statistically significant effect of surface roughening on the success of orthodontic mini-implants in humans. The overall failure rate of surface-roughened orthodontic mini-implants was 6%. FUNDING: No funding was received for this review. REGISTRATION: This study was preregistered in the Prospective Register of Systematic Reviews (CRD42022371830).

Influence of miniscrew-assisted rapid palatal expansion (MARPE) on the interdental papilla height of maxillary central incisors.

OBJECTIVES: To evaluate the influence of miniscrew-assisted rapid palatal expansion (MARPE) on the interdental papilla height of maxillary central incisors. MATERIALS AND METHODS: Patients who completed MARPE treatment at the Radboud University Medical Center between 2018 and 2021 were included in this retrospective study. The papilla height between the maxillary central incisors was evaluated on frontal intraoral photographs taken before expansion (T0) and 1.5 years after MARPE treatment (T1) using the Jemt classification. The difference in Jemt score at T0 and T1 was the primary outcome variable. In addition, gender, age, Angle classification, MARPE duration, midpalatal suture maturation stage, maximal central diastema (MCD) immediately after expansion, crown width to length ratio (W/L), pretreatment overlap of maxillary central incisors, and the distance between the approximal contact point of the central incisors and the bone crest (CP-B) were also record. RESULTS: Twenty-two patients were included (2 men, 20 women, mean age 27.3 ± 8.8 years) and 4 patients (18%) showed a significant reduction in the Jemt score following MARPE (p = 0.04), indicating papilla recession. Interdental papilla recession was significantly associated with the increase of CP-B (p = 0.02), smaller W/L (p < 0.01), overlapping of maxillary central incisors (p < 0.01), and smaller MCD immediately after expansion (p = 0.02). CONCLUSIONS: One and a half years after MARPE, 18% of patients exhibited mild recession of papilla height of the maxillary central incisors. Overlapping and smaller W/L of maxillary central incisors were prognostic factors for interdental papilla recession. CLINICAL RELEVANCE: Clinicians have to be aware of and inform the patients about the occurrence of papilla recession following MARPE.

What is the impact of miniscrew-assisted rapid palatal expansion on the midfacial soft tissues? A prospective three-dimensional stereophotogrammetry study.

OBJECTIVES: To evaluate the midfacial soft tissue changes of the face in patients treated with miniscrew-assisted rapid palatal expansion (MARPE). MATERIALS AND METHODS: 3D facial images and intra-oral scans (IOS) were obtained before expansion (T0), immediately after completion of expansion (T1), and 1 year after expansion (T2). The 3D images were superimposed and two 3D distance maps were generated to measure the midfacial soft tissue changes: immediate effects between timepoints T0 and T1 and overall effects between T0 and T2. Changes of the alar width were also measured and dental expansion was measured as the interpremolar width (IPW) on IOS. RESULTS: Twenty-nine patients (22 women, 7 men, mean age 25.9 years) were enrolled. The soft tissue in the regions of the nose, left of philtrum, right of philtrum, and upper lip tubercle demonstrated a statistically significant anterior movement of 0.30 mm, 0.93 mm, 0.74 mm, and 0.81 mm, respectively (p < 0.01) immediately after expansion (T0-T1). These changes persisted as an overall effect (T0-T2). The alar width initially increased by 1.59 mm, and then decreased by 0.08 mm after 1 year, but this effect was not significant. The IPW increased by 4.58 mm and remained stable 1 year later. There was no significant correlation between the increase in IPW and alar width (r = 0.35, p = 0.06). CONCLUSIONS: Our findings indicate that MARPE results in significant but small changes of the soft tissue in the peri-oral and nasal regions. However, the clinical importance of these findings is limited. CLINICAL RELEVANCE: MARPE is an effective treatment modality to expand the maxilla, incurring only minimal and clinically insignificant changes to the midfacial soft tissues.

Posterior Dahl: A Minimally Invasive Method for the Treatment of Localized Posterior Tooth Wear.

PURPOSE: This retrospective case series of 9 patients aimed to describe clinical outcomes and patient satisfaction following the implementation of the posterior Dahl concept to manage localized posterior tooth wear. MATERIALS AND METHODS: Localized occlusal space was created in the posterior dentition. Supra-occluding direct restorations were placed bilaterally for the restoration of molars. Intraoral scans were taken at the pre-treatment stage, immediately post-restoration, and during follow-up appointments. Scans were used to undertake analysis of any occlusal changes and re-establishment of the occlusion. A questionnaire was used to assess patient satisfaction, alleviation of any pre-treatment concerns, and evaluation of post-treatment complaints. RESULTS: Immediately post-treatment, all patients showed an increase in the vertical dimension. Opening of the bite in the untreated areas following restoration of worn posterior molars resulted either in a tendency towards or the actual reestablishment of the occlusion. One patient completely lacked compensatory vertical tooth movement in the untreated areas, culminating in the persistence of a vertical open bite. One restoration displayed cohesive fracture after 4 months. Pre-treatment problems (eg, sensitivity) were fully resolved amongst all patients after 6 months. Post-treatment complaints were minor and demonstrated resolution within a relatively short period of time. Eight patients reported being "very satisfied" with their treatment outcomes. CONCLUSION: Application of the posterior Dahl concept appears to offer a promising, relatively simple, minimally invasive and effective approach for the management of localized posterior tooth wear, which is well accepted by patients.

Do platelet concentrates accelerate orthodontic tooth movement?: a systematic review.

PURPOSE: Surgical techniques in orthodontics have received widespread attention in recent years. Meanwhile, biomaterials with high molecular content have been introduced, such as platelet concentrates (PCs), which may accelerate orthodontic tooth movement (OTM) and reduce periodontal damage. The present systematic review aimed to answer the following PICO question: "In patients in whom orthodontic surgical techniques are performed (P), what is the effectiveness of using PCs over the surgical site (I) when compared to not placing PCs (C) to achieve faster tooth movement (O)?" METHODS: A search was performed in 6 databases. The criteria employed were those described in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses declaration. The present review included studies with a control group that provided information about the influence of PCs on the rate of OTM. RESULTS: The electronic search identified 10 studies that met the established criteria. CONCLUSIONS: The included studies were very diverse, making it difficult to draw convincing conclusions. However, a tendency was observed for OTM to be accelerated when PCs were used as an adjuvant for canine distalization after premolar extraction when distalization was started in the same session. Likewise, studies seem to indicate an association between PC injection and the amount of canine retraction. However, it is not possible to affirm that the use of PCs in corticotomy shortens the overall treatment time, as this question has not been studied adequately. TRIAL REGISTRATION: PROSPERO Identifier: CRD42021278542.

What is the Oral Health-related Quality of Life following Miniscrew-Assisted Rapid Palatal Expansion (MARPE)? A prospective clinical cohort study.

BACKGROUND: Miniscrew-Assisted Rapid Palatal Expansion (MARPE) is a non-surgical orthodontic treatment for transverse maxillary deficiency. This study aimed to investigate the Oral Health-related Quality of Life (OHRQoL) and pain perception of patients undergoing MARPE treatment. METHODS: 42 consecutive patients (9 men, 33 women) from the age of 16 onwards (mean: 27.4 ± 9.3 years; range 17.1-55.7 years) who received a MARPE treatment were included. OHRQoL was assessed with the short form of the Oral Health Impact Profile (OHIP-14) questionnaire. Patients filled out the questionnaire at baseline (T0) and weekly during the expansion phase (P1) and in the post-expansion phase (P2). Pain intensity was assessed with a Visual Analogue Scale (VAS) questionnaire and filled out daily during expansion, along with a question on the intake of analgesics. The mean weekly and total OHIP-score and OHIP-score per domain were calculated at T0, P1 and P2, as well as mean weekly and total VAS-scores for average pain, maximum pain and analgesics intake during P1. Kruskal-Wallis tests were used to test for differences in OHIP between T0, P1 and P2. The level of significance was set at 0.05. RESULTS: The mean OHIP-score was 10.86 ± 9.71 at T0 and increased to 17.18 ± 10.43 during P1 (p < 0.001), after which it returned to pre-expansion levels, 9.27 ± 7.92 (p = 0.907) during P2. At the domain level, there was a statistically significant increase in OHIP-score at P1 for functional limitation, physical pain, psychological discomfort and social disability. The mean VAS-score for average pain during expansion was 16.00 ± 19.73 mm. Both OHIP-score (25.00 ± 10.25), average pain (33.72 ± 16.88 mm), maximum pain (44.47 ± 17.99 mm) and analgesics intake (59%) were highest at initiation of the expansion and decreased by the end of expansion. CONCLUSIONS: MARPE is a generally well-tolerated expansion treatment. A temporary decline in OHRQoL and moderate pain are present at the start of expansion, followed by a recovery of OHRQoL and very mild pain during the rest of treatment. Clinicians should be aware of the effects of MARPE on patients' quality of life and manage the expected discomfort and impediments with adequate communication and patient education.

Efficacy of Miniscrew-Assisted Rapid Palatal Expansion (MARPE) in late adolescents and adults with the Dutch Maxillary Expansion Device: a prospective clinical cohort study.

OBJECTIVES: To provide a higher degree of evidence on the efficacy of Miniscrew-Assisted Rapid Palatal Expansion (MARPE) in late adolescents and adults, thereby applying the Dutch Maxillary Expansion Device (D-MED). MATERIALS AND METHODS: D-MED was developed as an individualized, 3D-designed, and fabricated MARPE appliance supported by 4 palatal miniscrews. Patients from the age of 16 onwards with transverse maxillary deficiency were enrolled consecutively. Pre-expansion and immediate post-expansion CBCTs and intra-oral scans were acquired and measurements of skeletal, alveolar, and dental expansion as well as dental and periodontal side-effects were performed. RESULTS: Thirty-four patients were enrolled (8 men, 26 women) with mean age 27.0 ± 9.4 years. A success rate of 94.1% was achieved (32/34 patients). The mean expansion duration, or mean observation time, was 31.7 ± 8.0 days. The mean expansion at the maxillary first molars (M1) and first premolars (P1) was 6.56 ± 1.70 mm and 4.19 ± 1.29 mm, respectively. The expansion was 60.4 ± 20.1% skeletal, 8.1 ± 27.6% alveolar, and 31.6 ± 20.1% dental at M1 and 92.2 ± 14.5% skeletal, 0.0 ± 18.6% alveolar, and 7.8 ± 17.7% dental at P1, which was both statistically (p < 0.001) and clinically significant. Buccal dental tipping (3.88 ± 3.92° M1; 2.29 ± 3.89° P1), clinical crown height increase (0.12 ± 0.31 mm M1; 0.04 ± 0.22 mm P1), and buccal bone thinning (- 0.31 ± 0.49 mm M1; - 0.01 ± 0.45 mm P1) were observed, while root resorption could not be evaluated. CONCLUSIONS: MARPE by application of D-MED manifested its efficacy in a prospective clinical setting, delivering a high amount of skeletal expansion with limited side-effects in late adolescents and adults. CLINICAL RELEVANCE: Higher quality evidence is supportive of MARPE as a safe and successful non-surgical treatment option for transverse maxillary deficiency.

Efficacy of Miniscrew-Assisted Rapid Palatal Expansion (MARPE) in late adolescents and adults: a systematic review and meta-analysis.

BACKGROUND: Miniscrew-Assisted Rapid Palatal Expansion (MARPE) is a non-surgical treatment for transverse maxillary deficiency. However, there is limited evidence concerning its efficacy. OBJECTIVES: This systematic review aims to evaluate the efficacy of MARPE in late adolescents and adults by assessing success rate and skeletal and dental transverse maxillary expansion, as well as treatment duration, dental and periodontal side effects and soft tissue effects. SEARCH METHODS: Seven electronic databases were searched (MEDLINE, Embase, Cochrane Library, Web of Science, Scopus, ProQuest and ClinicalTrials.gov) without limitations in November 2020. SELECTION CRITERIA: Randomized and non-randomized clinical trials and observational studies on patients from the age of 16 onwards with transverse maxillary deficiency who were treated with MARPE and which included any of the predefined outcomes. DATA COLLECTION AND ANALYSIS: Inclusion eligibility screening, data extraction and risk of bias assessment were performed independently in duplicate. When possible, exploratory meta-analyses of mean differences (MDs) with their 95% confidence intervals (CIs) were conducted, followed by the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) analysis of the evidence quality. RESULTS: Eight articles were included: two prospective and six retrospective observational studies. One study had a moderate risk of bias, whereas seven studies had a serious risk of bias. GRADE quality of evidence was very low. MARPE showed a high success rate (mean: 92.5%; 95%CI: 88.7%-96.3%), resulting in a significant skeletal width increase (MD: 2.33 mm; 95%CI: 1.63 mm-3.03 mm) and dental intermolar width increase (MD: 6.55 mm; 95%CI: 5.50 mm-7.59 mm). A significant increase in dental tipping, a decrease in mean buccal bone thickness and buccal alveolar height, as well as nasal soft tissue change was present (P < 0.05). The mean duration of expansion ranged from 20 to 126 days. LIMITATIONS: One of the main drawbacks was the lack of high-quality prospective studies in the literature. CONCLUSIONS AND IMPLICATIONS: MARPE is a treatment modality that is associated with a high success rate in skeletal and dental maxillary expansion. MARPE can induce dental and periodontal side effects and affect peri-oral soft tissues. Given the serious risk of bias of the included studies, careful data interpretation is necessary and future research of higher quality is strongly recommended. REGISTRATION: PROSPERO (CRD42020176618). FUNDING: No grants or any other support funding were received.

Orthodontic radiology: development of a clinical practice guideline.

OBJECTIVES: Radiographs are considered essential in orthodontics. However, their diagnostic value and indications for use are still uncertain, while exposure to radiation carries health risks. This study aimed to report on the development of a clinical practice guideline on orthodontic radiology. METHODS: A Guideline Development Taskforce was set up. The GRADE methodology was used for development and the RIGHT Statement for reporting of the guideline. We systematically reviewed articles to address the main clinical question: how different types of radiographs contribute to orthodontic diagnosis, treatment planning and post-treatment outcome evaluation. After a literature search and data extraction, we formulated conclusions and assessed the strength of the evidence according to the GRADE method. Both literature conclusions and the most important considerations, such as patient preferences, organizational matters and expert opinions were taken into account to finally issue recommendations. RESULTS: 7 clinical questions focused on orthopantomograms, lateral cephalograms, hand-wrist radiographs, peri-apical radiographs, bitewings, antero-occlusal radiographs, and cone-beam computer tomographic imaging. The literature search lead to 484 unique studies, of which 17 were included in the analysis. The strength of evidence of the conclusions was graded low or very low. We formulated considerations and took them into account when issuing the 13 clinical recommendations to address the clinical questions. CONCLUSIONS: There was a considerable lack of scientific evidence on this topic. Nonetheless, this guideline provides clinicians with a tool for decision-making regarding radiographic records while enhancing patient radiation protection. More research of higher quality is recommended for a future update.

Combined orthodontic, surgical, and restorative approach to treat a complicated crown-root fracture in a maxillary central incisor.

This case report shows the treatment of a severe traumatic tooth injury. For the maxillary right central incisor, the trauma was considered a complicated crown-root fracture. The level of the fracture line, the length of the remaining root segment, and the presence and condition of the tooth fragment determined the type of therapy. Traumatized teeth with fractures below the alveolar crest are often considered hopeless. As this report shows, the treatment of a complicated crown-root fracture in the esthetic region can be challenging. Orthodontic extrusion and crown-length surgery were performed to bring the fracture line above the alveolar bone crest. A multidisciplinary approach was required for complete rehabilitation of the traumatized maxillary incisor. Suggestions are made to improve treatment planning of complicated crown-root fractures.

Effectiveness of a clinical guideline to improve dental health among orthodontically treated patients: study protocol for a cluster randomized controlled trial.

BACKGROUND: White spot lesions (WSLs) occur as a side effect in over 25 % of patients who undergo orthodontic treatment, causing aesthetic problems and a risk of deeper enamel and dentine lesions. Dutch orthodontists show substantial variation in their application of WSL preventive measures, which include little incorporation of evidence from the literature. We recently developed an evidence-based clinical practice guideline (CPG) on this topic, which was further converted into a computerized clinical decision support system (CDSS) to facilitate its incorporation into clinical practice. The present study aimed to assess the effectiveness of this CPG-based CDSS, with regard to actually preventing WSL development during orthodontic treatment with fixed appliances compared to usual preventive measures. Our study also aimed to evaluate the effects of implementing the CPG-based CDSS into routine clinical practice using a multifaceted strategy. METHODS/DESIGN: We designed a hybrid effectiveness-implementation study assessing both clinical effectiveness of the CPG and its implementation into routine practice. A total of 840 patients nested in 14 orthodontic practices will be randomly assigned as clusters to the intervention or the control arm. Patients recruited by the orthodontist in the intervention group will be treated following the CPG, while the usual preventative measures will be followed in the control arm. The primary outcome measure is the proportion of patients with newly formed or enlarged WSLs after 6-9 months of treatment with fixed appliances, and at the end of treatment, using the CPG for WSL prevention compared with usual preventive measures. An additional aim is to obtain some preliminary outcomes regarding the implementation process. DISCUSSION: This study investigates the effectiveness of a newly developed guideline to improve oral health during orthodontic treatment, while simultaneously illuminating potential difficulties in adopting a guideline in general orthodontic practice. The innovative features of this study include the risk-based CDSS that discriminates between patients' oral health statuses with regard to preventive measure utilization in general orthodontic practices. Most studies focusing on WSL prevention apply the preventive intervention to each patient in an experimental setting, resulting in overtreatment and a disconnect from the real-world conditions in which the intervention is to be applied. Additionally, one of the overreaching goals of this initiative is to create a gold standard for WSL prevention during orthodontic treatment, against which future studies can compare new promising preventive measures and the readiness of clinicians to change and adopt new treatments. By doing so, we want to help bridge the gap between science and orthodontic clinical practice and improve the quality of oral health care. TRIAL REGISTRATION: This trial is registered with the Dutch Trial Registry of the Dutch Cochrane Center under number NTR5012 , registration date 2 March 2015.

Another way of looking at treatment stability.

OBJECTIVE: To determine the contribution of normal physiological changes to the overall manifestation of a relapse after orthodontic treatment. We analyzed long-term changes in the dentition of patients with Class I malocclusions after orthodontic treatment compared with a representative group with untreated Class I malocclusions. MATERIALS AND METHODS: Study participants (n  =  66; mean age, 12 years at treatment initiation) were treated for Class I malocclusions. Dental changes were evaluated at 2, 5, 10, and 15 years after treatment. Control participants (n  =  79) had untreated Class I malocclusions (n  =  53 evaluated at ages 12 and 22 years; n  =  26 evaluated at ages 19 and 39 years). Dental changes were evaluated with the Peer Assessment Rating (PAR) index. RESULTS: In untreated and treated groups, PAR scores increased over time with gender-specific changes. In the untreated groups, the PAR score significantly increased in male participants between the ages of 12 and 22 years (P  =  .04) and in female participants between the ages of 19 and 39 years (P  =  .001). In the treated group, early posttreatment changes were primarily related to the initial treatment response. Later changes in the PAR score could be attributed to physiological changes, with the same gender-specific changes as those observed in the untreated group. CONCLUSIONS: The pattern of physiological changes in dentition for participants between the ages of 12 and 39 was different between sexes. Females showed more relapse than males between 10 and 15 years posttreatment. This distinction should be considered when evaluating long-term orthodontic treatment responses.

Methods to quantify soft tissue-based cranial growth and treatment outcomes in children: a systematic review.

CONTEXT: Longitudinal assessment of cranial dimensions of growing children provides healthcare professionals with information about normal and deviating growth as well as treatment outcome. OBJECTIVE: To give an overview of soft tissue-based methods for quantitative longitudinal assessment of cranial dimensions in children until age 6 years and to assess the reliability of these methods in studies with good methodological quality. DATA SOURCE: PubMed, EMBASE, Cochrane Library, Web of Science, Scopus, and CINAHL were searched. A manual search was performed to check for additional relevant studies. STUDY SELECTION: Primary publications on facial growth and treatment outcomes in children younger than age 6 years were included. DATA EXTRACTION: Independent data extraction was performed by two observers. A quality assessment instrument was used to determine methodological quality. Methods used in studies with good methodological quality were assessed for reliability expressed as the magnitude of the measurement error and the correlation coefficient between repeated measurements. RESULTS: In total, 165 studies were included, forming three groups of methods: head circumference anthropometry, direct anthropometry, and 2D photography and 3D imaging techniques (surface laser scanning and stereophotogrammetry). In general, the measurement error was below 2 mm, and correlation coefficients were very good. CONCLUSION: Various methods for measuring cranial dimensions have shown to be reliable. Stereophotogrammetry is the most versatile method for quantitative longitudinal assessment of cranial dimensions and shapes in children. However, direct anthropometry continues to be the best method for routine clinical assessments of linear cranial dimensions in growing children until age 6 years.

Volumetric changes of the nose and nasal airway 2 years after tooth-borne and bone-borne surgically assisted rapid maxillary expansion.

This study aimed to assess the effects of bone-borne and tooth-borne surgically assisted rapid maxillary expansion on the volumes of the nose and nasal airway 2 yr after maxillary expansion. This prospective cohort study included 32 patients with transverse maxillary hypoplasia. Expansion was performed with a tooth-borne distractor (Hyrax) in 19 patients and with a bone-borne distractor [transpalatal distractor (TPD)] in the remaining 13. Cone beam computed tomography scans and three-dimensional (3D) photographs of the face were acquired before treatment and 22 ± 7 months later, and were used to evaluate the volumes of the nose and nasal airway. Nasal volume increased by 1.01 ± 1.6% in the Hyrax group and by 2.39 ± 2.4% in the TPD group. Nasal airway volume increased by 9.7 ± 5.6% in the Hyrax group and by 12.9 ± 12.7% in the TPD group. Changes in the nasal volume and in the nasal airway volume between the pre- and post-treatment measurements were statistically significant, whereas differences between the treatment groups were not; 22 months after surgically assisted rapid maxillary expansion, the increases in the nasal volume and in the nasal airway volume were comparable between tooth-borne and bone-borne devices.

Accuracy and reliability of a novel method for fusion of digital dental casts and Cone Beam Computed Tomography scans.

Several methods have been proposed to integrate digital models into Cone Beam Computed Tomography scans. Since all these methods have some drawbacks such as radiation exposure, soft tissue deformation and time-consuming digital handling processes, we propose a new method to integrate digital dental casts into Cone Beam Computed Tomography scans. Plaster casts of 10 patients were randomly selected and 5 titanium markers were glued to the upper and lower plaster cast. The plaster models were scanned, impressions were taken from the plaster models and the impressions were also scanned. Linear measurements were performed on all three models, to assess accuracy and reproducibility. Besides that, matching of the scanned plaster models and scanned impressions was done, to assess the accuracy of the matching procedure. Results show that all measurement errors are smaller than 0.2 mm, and that 81% is smaller than 0.1 mm. Matching of the scanned plaster casts and scanned impressions show a mean error between the two surfaces of the upper arch of 0.14 mm and for the lower arch of 0.18 mm. The time needed for reconstructing the CBCT scans to a digital patient, where the impressions are integrated into the CBCT scan of the patient takes about 15 minutes, with little variance between patients. In conclusion, we can state that this new method is a reliable method to integrate digital dental casts into CBCT scans. As far as radiation exposure, soft tissue deformation and digital handling processes are concerned, it is a significant improvement compared to the previously published methods.

Three-dimensional evaluation of soft tissue changes in the orofacial region after tooth-borne and bone-borne surgically assisted rapid maxillary expansion.

OBJECTIVES: This study seeks to three-dimensionally assess soft tissue changes in the orofacial region following tooth-borne and bone-borne surgically assisted rapid maxillary expansion (SARME). MATERIALS AND METHODS: This prospective cohort study included 40 skeletally mature patients with transverse maxillary hypoplasia. A tooth-borne distractor (Hyrax) was used for expansion in 25 patients. In the remaining 15, a bone-borne distractor (transpalatal distractor, TPD) was used. Cone beam computed tomography (CBCT) scans were acquired before treatment (T0) and 22 months later (T1). 3D models were constructed from CBCT data and superimposed using voxel-based matching. Distance maps between the superimposed 3D models were computed to evaluate the degree of skeletal and soft tissue changes in the maxillary region. RESULTS: Distance maps showed negative distances (mean -1.25 (±1.5) mm) in the middle of the upper lip, indicating posterior repositioning of this area. The cheek region showed positive changes (mean 1.66 (±1.1) mm), reflecting the underlying increase in maxillary width. There was no significant difference between the two groups in all measured distances (p > 0.05). Retro-positioning of the upper lip accompanied skeletal remodeling in the anterior alveolar region at a mean ratio of 88 %, while the cheek region followed 32 % of the alveolar expansion. CONCLUSION: Soft tissue changes following SARME include posterior repositioning of the upper lip and increased projection of the cheek area. These changes were comparable between bone-borne and tooth-borne appliances. CLINICAL RELEVANCE: This study provides clinicians with more information over the expected orofacial soft tissue changes following SARME.

Dental models made with an intraoral scanner: a validation study.

INTRODUCTION: Our objectives were to determine the validity and reproducibility of measurements on stereolithographic models and 3-dimensional digital dental models made with an intraoral scanner. METHODS: Ten dry human skulls were scanned; from the scans, stereolithographic models and digital models were made. Two observers measured transversal distances, mesiodistal tooth widths, and arch segments on the skulls and the stereolithographic and digital models. All measurements were repeated 4 times. Arch length discrepancy and tooth size discrepancy were calculated. Statistical analysis was performed by using paired t tests. RESULTS: For the measurements on the stereolithographic and digital models, statistically significant differences were found. However, these differences were considered to be clinically insignificant. Digital models had fewer statistically significant differences and generally the smallest duplicate measurement errors compared with the stereolithographic models. CONCLUSIONS: Stereolithographic and digital models made with an intraoral scanner are a valid and reproducible method for measuring distances in a dentition.

Evidence supporting the use of cone-beam computed tomography in orthodontics.

BACKGROUND: The authors conducted a systematic review of cone-beam computed tomography (CBCT) applications in orthodontics and evaluated the level of evidence to determine whether the use of CBCT is justified in orthodontics. TYPES OF STUDIES REVIEWED: The authors identified articles by searching the Cochrane Library, PubMed, MEDLINE, Embase, Scopus and Cumulative Index to Nursing and Allied Health Literature databases. They searched the articles' reference lists manually for additional articles and had no language limitations. They did not search the gray literature. Inclusion criteria were CBCT use in orthodontics and that the participants be human. The lowest level of evidence accepted for inclusion was a case series with five or more participants. The authors evaluated the studies' methodological quality according to 13 criteria related to study design, measurements and statistical analysis. RESULTS: The authors identified 550 articles, and 50 met the inclusion criteria. Study topics included temporary anchorage devices, cephalometry, combined orthodontic and surgical treatment, airway measurements, root resorption and tooth impactions, and cleft lip and palate. The methodological quality averaged 53 percent (range, 15-77 percent) of the maximum score. CLINICAL IMPLICATIONS: The authors found no high-quality evidence regarding the benefits of CBCT use in orthodontics. Limited evidence shows that CBCT offers better diagnostic potential, leads to better treatment planning or results in better treatment outcome than do conventional imaging modalities. Only the results of studies on airway diagnostics provided sound scientific data suggesting that CBCT use has added value. The additional radiation exposure should be weighed against possible benefits of CBCT, which have not been supported in the literature. In future studies, investigators should evaluate the effects of CBCT on treatment procedures, progression and outcome quantitatively.

Width and elevation of the palatal shelves in unoperated unilateral and bilateral cleft lip and palate patients in the permanent dentition.

Patients with cleft left lip and palate (CLP) normally require extensive surgery from an early age up to the end of adolescence. These surgeries affect the growth of the maxillofacial complex. The degree to which the cleft itself affects growth of the maxillofacial complex remains poorly understood. By analysing the width and elevation of the palatal shelves in unoperated adolescents and adults with unilateral and bilateral cleft lip and palate (UCLP and BCLP, respectively) and a non-cleft control group, it is possible to gain more insight into the real intrinsic growth potential of the maxillary structures. In this study, dental casts of the full permanent dentition of individuals with unrepaired UCLP (n = 68) and BCLP (n = 13) and non-cleft controls (n = 24) from the same area of Indonesia were digitized three-dimensionally. Maxillary arch width in the canine, premolar and molar regions, and the width and elevation of the palatal shelves were measured. Results showed that in patients with UCLP, the width of the palatal shelves on the cleft side in all regions, and on the non-cleft side in the canine/first premolar region, was significantly smaller compared with the control group. BCLP subjects showed similar deviations. In the UCLP group, the palatal shelves were rotated cranially and positioned more vertically. In the BCLP group, the palatal shelves were inclined by almost 10 ° more than the control group. The width of the palatal shelf and width of the maxillary arch positively correlated in the canine and first premolar regions for both the cleft and non-cleft side in patients with UCLP, and in the canine region for patients with BCLP. This means that the wider the palatal shelf, the wider the maxillary arch. The elevation of palatal shelves correlated with the maxillary arch width in all regions in patients with UCLP, and only in the premolar region in the control group. Thus, the wider the arch width, the smaller the elevation angle (the maxillary shelves are less vertical). No correlations between palatal shelf elevation and maxillary arch width were found in the BCLP group. This shows that the intrinsic growth potential in patients with UCLP and BCLP is affected by a smaller palatal shelf width and larger elevation of the shelves. These deviations may result in a wider cleft.

Postoperative volume increase of facial soft tissue after percutaneous versus endonasal osteotomy technique in rhinoplasty using 3D stereophotogrammetry.

BACKGROUND: When lateral osteotomies are performed as part of a rhinoplasty, the nose and paranasal region invariably change in three dimensions. The PURPOSE of this study is to compare the effect of the percutaneous perforating and endonasal continuous osteotomy techniques concerning the degree of postoperative swelling using three dimensional (3D) stereophotogrammetry. METHODOLOGY: A prospective follow-up study was conducted. Patients requiring bilateral osteotomies were included and randomly underwent a percutaneous osteotomy on one side and an endonasal osteotomy on the other side. Pre- and postoperative 3D photos were acquired using 3D stereophotogrammetry. Volumetric measurement data were acquired from the paranasal region using 3D software. Measurements were compared using Student`s t-test and Wilcoxon signed rank test statistics. RESULTS: Twenty patients were included. A percutaneous osteotomy was performed on the right side in nine patients and on the left side in 11 patients. The total volume, the volume of the right paranasal and left paranasal region were significantly larger postoperative. No difference was found between the sides. CONCLUSIONS: No difference concerning swelling is found between the percutaneous and endonasal osteotomy technique sides. With 3D stereophotogrammetry volumetric data can be acquired and compared to evaluate soft-tissue changes.