Orthodontic tooth extrusion to regenerate missing papilla adjacent to maxillary anterior single implants: A 2- to 7-year retrospective study.

INTRODUCTION: Regeneration of the missing papilla adjacent to single implants in the esthetic zone has always been challenging, despite advances in vertical hard and soft tissue regeneration. Orthodontic tooth extrusion has been shown to effectively gain alveolar bone and gingival tissue. This retrospective study evaluated the effectiveness of orthodontic tooth extrusion on regenerating missing papilla between existing maxillary anterior single implant and its adjacent tooth. METHODS: Patients who underwent orthodontic tooth extrusion to regenerate missing papilla adjacent to a single implant in the esthetic zone were included in this study. The gingival phenotype, orthodontic extrusion movement, proximal bone level, dento-implant papilla level, facial gingival level, mucogingival junction level, and keratinized tissue width, of the extruded tooth were recorded at pre-orthodontic extrusion (T0 ), post-orthodontic extrusion and retention (T1 ), and latest follow-up (T2 ). RESULTS: A total of 17 maxillary single tooth had orthodontic tooth extrusion to regenerate missing papilla adjacent to 14 maxillary anterior single implants in 14 patients. After a mean follow-up time of 48.4 months, implant success rate was 100% (14/14), with none of the orthodontically extruded teeth being extracted. After a mean extrusion and retention period of 14.3 months, a mean orthodontic extrusion movement of 4.62 ± 0.78 mm was noted with a mean proximal bone level gain of 3.54 ± 0.61 mm (77.0% efficacy), dento-implant papilla level gain of 3.98 ± 0.81 mm (86.8% efficacy), and facial gingival tissue gain of 4.27 mm ± 0.55 mm (93.4% efficacy). A mean keratinized tissue width gain of 4.17 ± 0.49 mm with minimal mean mucogingival junction level change of 0.10 ± 0.30 mm were observed. The efficacy of orthodontic eruption movement on dento-implant papilla gain was less in the thin (80.5%) phenotype group when compared with that in the thick (91.5%) phenotype group. CONCLUSIONS: Within the confines of this study, orthodontic extrusion is an effective, noninvasive method in regenerating mid-term stable proximal bone and papilla adjacent to maxillary anterior single implants. CLINICAL SIGNIFICANCE: This retrospective study presents a mid-term result on orthodontic extrusion as a mean to regenerate dento-implant papilla defect. The extended retention period following orthodontic extrusion showed stable and efficacious proximal bone and papilla gain.

Replacement of an existing maxillary anterior fixed dental prosthesis, redo another fixed dental prosthesis, or convert to implants.

OBJECTIVE: The purpose of this article is to discuss the considerations that need to be evaluated when considering the replacement of an existing maxillary anterior fixed dental prosthesis (FDP) with another FDP, or when to consider converting to implants and individual crowns on the previous abutment teeth. OVERVIEW: The need to replace unesthetic or failing maxillary anterior FDPs is something all restorative dentists will be faced with multiple times in their careers. Given the emphasis over the past few decades on utilizing implants for tooth replacement as opposed to a tooth supported FDP, the question becomes when is converting the existing FDP to implants and single crowns an appropriate choice, as opposed to redoing a new FDP. This article will focus on the risks of choosing to convert to an implant solution, and the risks of redoing the tooth supported FDP. Multiple systematic reviews on each approach will be used to aid in the decision process. The most significant risks for both approaches will be identified, and a chart of the key parameters to assess will be presented, along with their impact. CONCLUSIONS: The statistical outcomes at 5 and 10 years of tooth supported FDPs, and Implant based restorations are very similar if certain clinical parameters are met, namely vital healthy abutment teeth for the FDP, and adequate bone and soft tissue for the implant-based restoration. If one abutment tooth is compromised the long-term prognosis drops significantly and converting to an implant-based restoration may be more predictable. Similarly, if adequate bone and soft tissue cannot be obtained through surgical augmentation procedures, using a connective tissue graft for the ridge, and redoing the FDP may obtain a more acceptable esthetic result. CLINICAL SIGNIFICANCE: A significant number of maxillary anterior FDPs exist that will need replacement in the future. Given the desire of many dentists to utilize implants when possible, there can be a tendency to automatically treatment plan an implant-based approach for replacement of the existing FDP. Certainly, most clinicians would favor an implant-based tooth replacement rather than preparing unrestored teeth to place an FDP, but when an existing FDP exists, the teeth have already been prepared for full coverage in most instances. In addition, for most long term existing FDPs, there is a significant change in the vertical and horizontal dimension of the bone and soft tissue that can make getting an acceptable esthetic result with an implant challenging. This article provides a systematic approach to identifying when redoing the FDP may be preferable, or when converting to an implant-based approach is a better choice.

Shear heating reconciles thermal models with the metamorphic rock record of subduction.

Some commonly referenced thermal-mechanical models of current subduction zones imply temperatures that are 100-500 °C colder at 30-80-km depth than pressure-temperature conditions determined thermobarometrically from exhumed metamorphic rocks. Accurately inferring subduction zone thermal structure, whether from models or rocks, is crucial for predicting metamorphic reactions and associated fluid release, subarc melting conditions, rheologies, and fault-slip phenomena. Here, we compile surface heat flow data from subduction zones worldwide and show that values are higher than can be explained for a frictionless subduction interface often assumed for modeling. An additional heat source--likely shear heating--is required to explain these forearc heat flow values. A friction coefficient of at least 0.03 and possibly as high as 0.1 in some cases explains these data, and we recommend a provisional average value of 0.05 ± 0.015 for modeling. Even small coefficients of friction can contribute several hundred degrees of heating at depths of 30-80 km. Adding such shear stresses to thermal models quantitatively reproduces the pressure-temperature conditions recorded by exhumed metamorphic rocks. Comparatively higher temperatures generally drive rock dehydration and densification, so, at a given depth, hotter rocks are denser than colder rocks, and harder to exhume through buoyancy mechanisms. Consequently--conversely to previous proposals--exhumed metamorphic rocks might overrepresent old-cold subduction where rocks at the slab interface are wetter and more buoyant than in young-hot subduction zones.

Long-term management of avulsed "hopeless" teeth in the adult dentition.

OBJECTIVE: This case will demonstrate a thoughtful approach to the management of avulsed/replanted teeth in the adult dentition and their long-term maintenance. Often times these teeth are either not replanted, or extracted soon after replantation when resorptive lesions appear and the teeth are deemed "hopeless". The term "hopeless tooth" (HT) has become more popular since the advent of implants. Implants allowed for a simple solution to the HT by extraction and immediate replacement with a fixture and a restoration. However, now that we are realizing that implants do not last forever and also have attendant problems, saving the HT takes on a new light. CLINICAL CONSIDERATIONS: Prolonging the life of the HT can preserve bone and give the patient a functional, esthetic tooth for many years. With each additional year, clinicians garner new skills, and technology improves our future treatment outcomes. This will allow clinicians to improve and extend the life of future replacements. CONCLUSIONS: If there is minimal risk to adjacent structures, retaining the HT has many advantages for the patient and clinician. Clinicians should adopt a policy of thinking ahead and asking "What's Next"? when their prospective treatment fails or needs to be replaced. By prolonging the life of the HT, the "best ultimate treatment" has a greater chance to outlive the patient. CLINICAL SIGNIFICANCE: With the advent of single tooth implants, the term "hopeless tooth" has become more popular. It is easier to justify extraction of a tooth when it is deemed "hopeless". Many of these teeth could be saved. The advantages of this philosophy will be elucidated.

Which all-ceramic system is optimal for anterior esthetics?

BACKGROUND: As ceramic materials for dentistry evolve and patients' demand for esthetic restorations increases, practitioners must keep up with the science as well as the demand. The authors offer guidance to the practitioner in selecting the appropriate all-ceramic systems for crowns when faced with different esthetic demands. CONCLUSIONS: Clinicians should reserve dental ceramics with high translucency for clinical applications in which high-level esthetics are required and the restoration can be bonded to tooth structure. Ceramics with high strength tend to be more opaque and pose a challenge when trying to match natural tooth color, but they can mask discoloration when present. PRACTICE IMPLICATIONS: Knowledge of the optical properties of available ceramic systems enable the clinician to make appropriate choices when faced with various esthetic challenges.

The use of implants and ovate pontics in the esthetic zone.

This article will discuss and evaluate the potential conditions that can present in patients who require or already have had multiple anterior tooth extractions; the proper considerations for the use of ovate pontics in the treatment plan also will be discussed. While the ultimate treatment decisions must be determined on a case-by-case basis, it is important to recognize in advance the various potential outcomes to ensure that realistic decisions are made about the best treatment options for each patient. Accordingly, the four most common presentations a clinician is likely to encounter will be examined, as well as how they may be managed and the most likely compromises that might exist in the final result.

The esthetic management of a severe isolated periodontal defect in the maxillary anterior.

A 30-plus year-old woman presented to the periodontist with a chief complaint concerning the esthetics of the black space between her maxillary right lateral and central incisors (Figure 1). The history of the problem dated back several years when her general dentist noted increased pocket depth in this area. The patient was referred to a periodontist who elected to attempt grafting in this site to improve both the bone and soft tissue. The patient reported that after the initial surgery the defect became significantly worse and a large quantity of gingival tissue was lost. The patient was then referred to a second periodontist who, after evaluation, also chose to attempt both a bone and soft tissue grafting procedure and again the defect became worse. At that point the second periOdontist referred the patient to the periodontist in our group for evaluation and treatment. At her initial consultation the patient indicated she had been managing the defect esthetically by placing pink wax into the large open space every day to minimize the appearance.

A multidisciplinary approach to esthetic dentistry.

Today's dentist does not just repair teeth to make them better for chewing. Increasingly, his or her work involves esthetics. With patients demanding more attractive teeth, dentists now must become more familiar with the formerly independent disciplines of orthodontics, periodontics, restorative dentistry, and maxillofacial surgery. This article provides a systematic method of evaluating dentofacial esthetics in a logical, interdisciplinary manner. In today's interdisciplinary dental world, treatment planning must begin with well-defined esthetic objectives. By beginning with esthetics, and taking into consideration the impact on function, structure, and biology, the clinician will be able to use the various disciplines in dentistry to deliver the highest level of dental care to each patient.

Interdisciplinary management of anterior dental esthetics.

BACKGROUND: Dental esthetics has become a popular topic among all disciplines in dentistry. When a makeover is planned for the esthetic appearance of a patient's teeth, the clinician must have a logical diagnostic approach that results in the appropriate treatment plan. With some patients, the restorative dentist cannot accomplish the correction alone but may require the assistance of other dental disciplines. APPROACH: This article describes an interdisciplinary approach to the diagnosis and management of anterior dental esthetics. The authors practice different disciplines in dentistry: restorative care, orthodontics and periodontics. However, for more than 20 years, this team has participated in an interdisciplinary dental study group that focuses on a wide variety of dental problems. One such area has been the analysis of anterior dental esthetic problems requiring interdisciplinary correction. This article will describe a unique approach to interdisciplinary dental diagnosis, beginning with esthetics but encompassing structure, function and biology to achieve an optimal result. CLINICAL IMPLICATIONS: If a clinician uses an esthetically based approach to the diagnosis of anterior dental problems, then the outcome of the esthetic treatment plan will be enhanced without sacrificing the structural, functional and biological aspects of the patient's dentition.

The esthetic correction of anterior dental mal-alignment conventional vs. instant (restorative) orthodontics.

Creating a flow sheet may assist in the decision whether to use conventional orthodontics and what the limitations of treating the patient will be if treatment is performed without any orthodontics. The decision process can be viewed as a series of questions, and depending upon the answer to the questions, the practitioner and patient can decide on whether to involve orthodontics or not. Questions can create a framework to help separate the patients who would benefit from orthodontic intervention from those we all enjoy treating who can be managed with purely restorative care.

My growing involvement in dental study groups.

The lessons from managing a successful study club are learned over a life-time of practice, just a dentistry is. The author, who has taught numerous participation continuing education courses using the study club model and mentored many study clubs identifies these criteria for success: a respected mentor, open feedback, multiple points, of view, a clear mission and structure, and attention to the changing needs of the participants over time. A study club that has renewed itself effectively over a twenty-year period is described as a possible model.