Introduction : Novel expandable short dental implants in situations with reduced vertical bone height—technical note and first results [1]
Endosseous implants have been established over several decades. The evaluation of treatment results under biomechanical, physiological, psychological, social and economic aspects has been well documented [1]. Furthermore, patient-based outcomes reveal a predictable gain in oral health-related quality of life [2].
Especially in patients with limited vertical bone height, process of treatment is extensive. Prior to implantation, augmentation procedures are required [3]. Depending on gender, vascularisation and bone mineralisation up to 25% of the primary volume are resorbed due to remodeling of augmented alveolar ridges [4]. Recently, short dental implants have evolved into a promising and reliable treatment option in the orofacial rehabilitation of atrophic mandibles and maxillae, namely as an alternative to vertical ridge augmentation [5,6,7,8]. The prognosis of short implants and patient satisfaction is high [9,10,11,12].
The definition of short implants in the literature is not uniform. In this present study, we considered short implants with 5–8-mm length [5, 7, 13]. Other authors set the cut-off at 6 mm [8, 9, 11, 14, 15]. According to the recent consensus paper of the 11th European Consensus Conference (EuCC), dental implants are referred to as “short” if their intrabony length measures ≤ 8 mm and considered as “ultra-short” with lengths < 6 mm [16].
Biomechanical studies show that the crestal bone is strained under axial and extra-axial loading [17]. While bone quality, implant design and position, prosthetic devices and material characteristics contribute to the character of stress distribution, the role of implant length seems to be of underpart [17, 18]. Nevertheless, implant length is crucial in D4 bone quality [19], and the crown-to-implant length itself influences stress distribution under extra-axial loading in the crestal bone [20] and in the abutment screw [21]. According to Petrie and Williams [22], the influence of increased implant diameter on stress reduction in the crestal bone is more efficient than increased implant length. Möhlhenrich and co-authors [23] confirmed these findings that the diameter of an implant has greater influence on primary stability than implant length. Based on in vitro analysis, they concluded additionally that especially in patients with poor bone quality, a variation of implant dimensions is expected to lead to a significant increase of primary stability. Furthermore, stress distribution on short implants is affected by the bone-to-implant contact ratio [24]. Consequently, several options to increase the implant surface of short implants are elaborated, which consecutively enhance the implant stability: thread number, thread shape, thread depth, implant diameter, implant design and surface topography [25,26,27].
Serial posts:
- Abstract : Novel expandable short dental implants in situations with reduced vertical bone height—technical note and first results
- Introduction : Novel expandable short dental implants in situations with reduced vertical bone height—technical note and first results [1]
- Introduction : Novel expandable short dental implants in situations with reduced vertical bone height—technical note and first results [2]
- Material and methods : Novel expandable short dental implants in situations with reduced vertical bone height—technical note and first results [1]
- Material and methods : Novel expandable short dental implants in situations with reduced vertical bone height—technical note and first results [2]
- Material and methods : Novel expandable short dental implants in situations with reduced vertical bone height—technical note and first results [3]
- Results : Novel expandable short dental implants in situations with reduced vertical bone height—technical note and first results [1]
- Results : Novel expandable short dental implants in situations with reduced vertical bone height—technical note and first results [2]
- Discussion : Novel expandable short dental implants in situations with reduced vertical bone height—technical note and first results [1]
- Discussion : Novel expandable short dental implants in situations with reduced vertical bone height—technical note and first results [2]
- Discussion : Novel expandable short dental implants in situations with reduced vertical bone height—technical note and first results [3]
- Discussion : Novel expandable short dental implants in situations with reduced vertical bone height—technical note and first results [4]
- Discussion : Novel expandable short dental implants in situations with reduced vertical bone height—technical note and first results [5]
- Conclusion : Novel expandable short dental implants in situations with reduced vertical bone height—technical note and first results
- Abbreviations : Novel expandable short dental implants in situations with reduced vertical bone height—technical note and first results
- References : Novel expandable short dental implants in situations with reduced vertical bone height—technical note and first results [1]
- References : Novel expandable short dental implants in situations with reduced vertical bone height—technical note and first results [2]
- References : Novel expandable short dental implants in situations with reduced vertical bone height—technical note and first results [3]
- References : Novel expandable short dental implants in situations with reduced vertical bone height—technical note and first results [4]
- References : Novel expandable short dental implants in situations with reduced vertical bone height—technical note and first results [5]
- References : Novel expandable short dental implants in situations with reduced vertical bone height—technical note and first results [6]
- References : Novel expandable short dental implants in situations with reduced vertical bone height—technical note and first results [7]
- Acknowledgements : Novel expandable short dental implants in situations with reduced vertical bone height—technical note and first results
- Author information : Novel expandable short dental implants in situations with reduced vertical bone height—technical note and first results [1]
- Author information : Novel expandable short dental implants in situations with reduced vertical bone height—technical note and first results [2]
- Additional files : Novel expandable short dental implants in situations with reduced vertical bone height—technical note and first results
- Rights and permissions : Novel expandable short dental implants in situations with reduced vertical bone height—technical note and first results
- About this article : Novel expandable short dental implants in situations with reduced vertical bone height—technical note and first results
- Table 1 Patient recruitment : Novel expandable short dental implants in situations with reduced vertical bone height—technical note and first results
- Table 2 Surgical treatment protocol : Novel expandable short dental implants in situations with reduced vertical bone height—technical note and first results
- Table 3 Prosthetic treatment protocol : Novel expandable short dental implants in situations with reduced vertical bone height—technical note and first results
- Table 4 Clinical characteristics of the study cohort : Novel expandable short dental implants in situations with reduced vertical bone height—technical note and first results
- Fig. 1. a Closed short expandable dental implant (4.1 × 7 mm). The implant-abutment connection is characterised by an internal hexagon for rotation stability, combining the advantages of conical and parallel surfaces to reduce microgaps and micromovement [68]. The microthread concept and platform switching concept are implemented in the implant shoulder to reduce periimplant bone strain [53]. b Manual fixation of the expansion tool. Take note of the distance between both yellow rings. c Completion of the expansion process using the ratchet. Take note of the contact between both yellow rings. d Opened short expandable dental implant (4.1 × 7 mm). The expanded implant provides an increased bone-to-implant interface (pyramid shape) in the apical portion [54]. e Cross-section view of the implant apex. The apical expansion process is characterised by the unfolding of four wings, which are connected by four foils. D1: diameter of the closed implant. D2: diameter of the opened implant. fTop v
- Fig. 2. Cumulative implant survival over the follow-up period. The Kaplan-Meyer diagram visualises the analysis of implant survival in the maxilla and in the mandible (log rank test, p = 0.173) over the follow-up period up to 37 months (Table 4) : Novel expandable short dental implant
- Fig. 3. a Primary implant stability. The histogram visualises the distribution of the implant stability quotients (ISQ) for both jaws measured by resonance frequency analysis (Osstell AB, Göteborg, Sweden). b Secondary implant stability. The histogram shows the distribution of the implant stability quotients (ISQ) of osseointegrated implants. According to the measurement implant stability was classified as low with ISQ values < 60, medium with ISQ values 60–70, and high with values ISQ > 70 [34] : Novel expandable short dental implant
- Fig. 4. a–h Prosthetic restauration—follow-up examination. Intraoral and perioral views of a rehabilitated female patient. (She asked explicitly only for implantological treatment in the mandible.) : Novel expandable short dental implant
- Fig. 5. a Postoperative orthopantomogram. b Follow-up orthopantomogram. c Follow-up standard periapical radiogram (implants i42 and i44). d Follow-up standard periapical radiogram (implants i32 and i34) : Novel expandable short dental implant